National Library of Energy BETA

Sample records for large area telescope

  1. GLAST Large Area Telescope Multiwavelength Planning

    E-Print Network [OSTI]

    O. Reimer; P. F. Michelson; R. A. Cameron; S. W. Digel; D. J. Thompson; K. S. Wood

    2006-11-21

    Gamma-ray astrophysics depends in many ways on multiwavelength studies. The Gamma-ray Large Area Space Telescope (GLAST) Large Area Telescope (LAT) Collaboration has started multiwavelength planning well before the scheduled 2007 launch of the observatory. Some of the high-priority multiwavelength needs include: (1) availability of contemporaneous radio and X-ray timing of pulsars; (2) expansion of blazar catalogs, including redshift measurements; (3) improved observations of molecular clouds, especially at high galactic latitudes; (4) simultaneous broad-band blazar monitoring; (5) characterization of gamma-ray transients, including gamma ray bursts; (6) radio, optical, X-ray and TeV counterpart searches for reliable and effective sources identification and characterization. Several of these activities are needed to be in place before launch.

  2. Fermi Large Area Telescope Third Source Catalog

    E-Print Network [OSTI]

    ,

    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 emission, a refined procedure for source detection, and improved methods for associating LAT sources with potential counterparts at other wavelengths. The 3FGL catalog includes 3033 sources above 4 sigma significance, with source location regions, spectral properties, and monthly light curves for each. Of these, 78 are flagged as potentially being due to imperfections in the model for Galactic diffuse emission. Twenty-five sources are modeled explicitly as spatially extended, and overall 232 sources are considered as identifie...

  3. Fermi Large Area Telescope Observations of the Supernova Remnant...

    Office of Scientific and Technical Information (OSTI)

    of the Supernova Remnant G8.7-0.1 We present a detailed analysis of the GeV gamma-ray emission toward the supernova remnant (SNR) G8.7-0.1 with the Large Area Telescope (LAT) on...

  4. FERMI LARGE AREA TELESCOPE OBSERVATIONS OF GRB 110625A

    SciTech Connect (OSTI)

    Tam, P. H. T.; Kong, A. K. H. [Institute of Astronomy and Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Fan Yizhong, E-mail: phtam@phys.nthu.edu.tw [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)

    2012-08-01

    Gamma-ray bursts (GRBs) that emit photons at GeV energies form a small but significant population of GRBs. However, the number of GRBs whose GeV-emitting period is simultaneously observed in X-rays remains small. We report {gamma}-ray observations of GRB 110625A using Fermi's Large Area Telescope in the energy range 100 MeV-20 GeV. Gamma-ray emission at these energies was clearly detected using data taken between 180 s and 580 s after the burst, an epoch after the prompt emission phase. The GeV light curve differs from a simple power-law decay, and probably consists of two emission periods. Simultaneous Swift X-Ray Telescope observations did not show flaring behaviors as in the case of GRB 100728A. We discuss the possibility that the GeV emission is the synchrotron self-Compton radiation of underlying ultraviolet flares.

  5. The Kilodegree Extremely Little Telescope (KELT): A Small Robotic Telescope for Large-Area Synoptic Surveys

    E-Print Network [OSTI]

    Joshua Pepper; Richard W. Pogge; D. L. DePoy; J. L. Marshall; K. Z. Stanek; Amelia M. Stutz; Shawn Poindexter; Robert Siverd; Thomas P. O'Brien; Mark Trueblood; Patricia Trueblood

    2007-07-30

    The Kilodegree Extremely Little Telescope (KELT) project is a survey for planetary transits of bright stars. It consists of a small-aperture, wide-field automated telescope located at Winer Observatory near Sonoita, Arizona. The telescope surveys a set of 26 x 26 degree fields, together covering about 25% of the Northern sky, targeting stars in the range of 8

  6. The On-Orbit Calibrations for the Fermi Large Area Telescope

    SciTech Connect (OSTI)

    Abdo, Aous A.; /Naval Research Lab, Wash., D.C.; Ackermann, M.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Ajello, M.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Ampe, J.; /Naval Research Lab, Wash., D.C.; Anderson, B.; /UC, Santa Cruz; Atwood, W.B.; /UC, Santa Cruz; Axelsson, M.; /Stockholm U., OKC /Stockholm U.; Bagagli, R.; /INFN, Pisa; Baldini, L.; /INFN, Pisa; Ballet, J.; /DAPNIA, Saclay; Barbiellini, Guido; /INFN, Trieste /Trieste U.; Bartelt, J.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bastieri, Denis; /INFN, Padua /Padua U.; Baughman, B.M.; /Ohio State U.; Bechtol, K.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bederede, D.; /DAPNIA, Saclay; Bellardi, F.; /INFN, Pisa; Bellazzini, R.; /INFN, Pisa; Belli, F.; /Frascati /Rome U.,Tor Vergata; Berenji, B.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bisello, D.; /INFN, Padua /Padua U. /Garching, Max Planck Inst., MPE /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Ecole Polytechnique /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /INFN, Perugia /Perugia U. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /DAPNIA, Saclay /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /INFN, Pisa /INFN, Pisa /Bari U. /INFN, Bari /Ecole Polytechnique /Washington U., Seattle /INFN, Padua /Padua U. /Bari U. /INFN, Bari /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /IASF, Milan /IASF, Milan /Kalmar U. /Stockholm U., OKC /Royal Inst. Tech., Stockholm /DAPNIA, Saclay /ASDC, Frascati /INFN, Pisa /INFN, Perugia /Perugia U. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /George Mason U. /Naval Research Lab, Wash., D.C. /NASA, Goddard /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /DAPNIA, Saclay /NASA, Goddard /INFN, Perugia /Perugia U.; /more authors..

    2011-11-17

    The Large Area Telescope (LAT) on-board the Fermi Gamma-ray Space Telescope began its on-orbit operations on June 23, 2008. Calibrations, defined in a generic sense, correspond to synchronization of trigger signals, optimization of delays for latching data, determination of detector thresholds, gains and responses, evaluation of the perimeter of the South Atlantic Anomaly (SAA), measurements of live time, of absolute time, and internal and spacecraft boresight alignments. Here we describe on-orbit calibration results obtained using known astrophysical sources, galactic cosmic rays, and charge injection into the front-end electronics of each detector. Instrument response functions will be described in a separate publication. This paper demonstrates the stability of calibrations and describes minor changes observed since launch. These results have been used to calibrate the LAT datasets to be publicly released in August 2009.

  7. Indirect Searches for Dark Matter with the Fermi Large Area Telescope1

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Albert, Andrea

    2015-01-01

    There is overwhelming evidence that non-baryonic dark matter constitutes ~ 27% of the energy density of the Universe. Weakly Interacting Massive Particles (WIMPs) are promising dark matter candidates that may produce ? rays via annihilation or decay detectable by the Fermi Large Area Telescope (LAT). A detection of WIMPs would also indicate the existence of physics beyond the Standard Model. We present recent results from the two cleanest indirect WIMP searches by the Fermi-LAT Collaboration: searches for ?-ray spectral lines and ?-ray emission associated with Milky Way dwarf spheroidal satellite galaxies.

  8. Indirect searches for dark matter with the Fermi large area telescope

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Albert, Andrea

    2015-03-24

    There is overwhelming evidence that non-baryonic dark matter constitutes ~ 27% of the energy density of the Universe. Weakly Interacting Massive Particles (WIMPs) are promising dark matter candidates that may produce ? rays via annihilation or decay detectable by the Fermi Large Area Telescope (LAT). A detection of WIMPs would also indicate the existence of physics beyond the Standard Model. We present recent results from the two cleanest indirect WIMP searches by the Fermi-LAT Collaboration: searches for ?-ray spectral lines and ?-ray emission associated with Milky Way dwarf spheroidal satellite galaxies.

  9. Fermi Large Area Telescope Constraints on the Gamma-ray Opacity of the

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverse (Journal Article) | SciTech Connect Large Area Telescope Constraints on

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

    SciTech Connect (OSTI)

    Ackermann, M.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Ajello, M.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Allafort, A.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Atwood, W.B.; /UC, Santa Cruz; Axelsson, M.; /Stockholm U. /Stockholm U., OKC /Royal Inst. Tech., Stockholm; Baldini, L.; /INFN, Pisa; Barbiellini, G.; /INFN, Trieste /Trieste U.; Bastieri, D.; /INFN, Padua /Padua U.; Bechtol, K.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Bellazzini, R.; /INFN, Pisa; Berenji, B.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Bloom, E.D.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Bonamente, E.; /INFN, Perugia /Perugia U.; Borgland, A.W.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Bouvier, A.; /UC, Santa Cruz; Bregeon, J.; /INFN, Pisa; Brez, A.; /INFN, Pisa; Brigida, M.; /Bari Polytechnic /INFN, Bari; Bruel, P.; /Ecole Polytechnique; Buehler, R.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Buson, S.; /INFN, Padua /Padua U. /CSIC, Catalunya /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /IASF, Milan /DAPNIA, Saclay /INFN, Perugia /Perugia U. /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Unlisted, US /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /ASDC, Frascati /Perugia U. /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Montpellier U. /ASDC, Frascati /Bari Polytechnic /INFN, Bari /Naval Research Lab, Wash., D.C. /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Montpellier U. /Bari Polytechnic /INFN, Bari /Ecole Polytechnique /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Ecole Polytechnique /Hiroshima U. /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Bari Polytechnic /INFN, Bari /INFN, Bari /NASA, Goddard /INFN, Perugia /Perugia U.; /more authors..

    2012-09-20

    The Large Area Telescope (LAT) on-board the Fermi Gamma-ray Space Telescope is a pair-conversion telescope designed to survey the gamma-ray sky from 20 MeV to several hundreds of GeV. In this energy band there are no astronomical sources with sufficiently well known and sharp spectral features to allow an absolute calibration of the LAT energy scale. However, the geomagnetic cutoff in the cosmic ray electron-plus-positron (CRE) spectrum in low Earth orbit does provide such a spectral feature. The energy and spectral shape of this cutoff can be calculated with the aid of a numerical code tracing charged particles in the Earth's magnetic field. By comparing the cutoff value with that measured by the LAT in different geomagnetic positions, we have obtained several calibration points between {approx}6 and {approx}13 GeV with an estimated uncertainty of {approx}2%. An energy calibration with such high accuracy reduces the systematic uncertainty in LAT measurements of, for example, the spectral cutoff in the emission from gamma ray pulsars.

  11. Fermi Large Area Telescope Observations of the Supernova Remnant G8.7-0.1

    E-Print Network [OSTI]

    ,

    2011-01-01

    We present a detailed analysis of the GeV gamma-ray emission toward the supernova remnant (SNR) G8.7-0.1 with the Large Area Telescope (LAT) onboard the \\emph{Fermi} Gamma-ray Space Telescope. An investigation of the relationship among G8.7-0.1 and the TeV unidentified source HESS J1804-216 provides us with an important clue on diffusion process of cosmic rays if particle acceleration operates in the SNR. The GeV gamma-ray emission is extended with most of the emission in positional coincidence with the SNR G8.7-0.1 and a lesser part located outside the western boundary of G8.7-0.1. The region of the gamma-ray emission overlaps spatially-connected molecular clouds, implying a physical connection for the gamma-ray structure. The total gamma-ray spectrum measured with LAT from 200 MeV--100 GeV can be described by a broken power-law function with a break of 2.4 $\\pm$ 0.6 (stat) $\\pm$ 1.2 (sys) GeV, and photon indices of 2.10 $\\pm$ 0.06 (stat) $\\pm$ 0.10 (sys) below the break and 2.70 $\\pm$ 0.12 (stat) $\\pm$ 0.14...

  12. Fermi Large Area Telescope Observations of the Cygnus Loop Supernova Remnant

    SciTech Connect (OSTI)

    Katagiri, H.; /Ibaraki U., Mito; Tibaldo, L.; /INFN, Padua /Padua U. /Paris U., VI-VII; Ballet, J.; /Paris U., VI-VII; Giordano, F.; /Bari U. /Bari Polytechnic /INFN, Bari; Grenier, I.A.; /Paris U., VI-VII; Porter, T.A.; /Stanford U., HEPL /KIPAC, Menlo Park /SLAC; Roth, M.; /Washington U., Seattle; Tibolla, O.; /Wurzburg U.; Uchiyama, Y.; /Stanford U., HEPL /KIPAC, Menlo Park /SLAC; Yamazaki, R.; /Sagamihara, Aoyama Gakuin U.

    2011-11-08

    We present an analysis of the gamma-ray measurements by the Large Area Telescope (LAT) onboard the Fermi Gamma-ray Space Telescope in the region of the supernova remnant (SNR) Cygnus Loop (G74.0-8.5). We detect significant gamma-ray emission associated with the SNR in the energy band 0.2-100 GeV. The gamma-ray spectrum shows a break in the range 2-3 GeV. The gamma-ray luminosity is {approx} 1 x 10{sup 33} erg s{sup -1} between 1-100 GeV, much lower than those of other GeV-emitting SNRs. The morphology is best represented by a ring shape, with inner/outer radii 0{sup o}.7 {+-} 0{sup o}.1 and 1{sup o}.6 {+-} 0{sup o}.1. Given the association among X-ray rims, H{alpha} filaments and gamma-ray emission, we argue that gamma rays originate in interactions between particles accelerated in the SNR and interstellar gas or radiation fields adjacent to the shock regions. The decay of neutral pions produced in nucleon-nucleon interactions between accelerated hadrons and interstellar gas provides a reasonable explanation for the gamma-ray spectrum.

  13. PROBING MILLISECOND PULSAR EMISSION GEOMETRY USING LIGHT CURVES FROM THE FERMI/LARGE AREA TELESCOPE

    SciTech Connect (OSTI)

    Venter, C.; Harding, A. K. [Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Guillemot, L. [Universite de Bordeaux, Centre d'Etudes Nucleaires Bordeaux Gradignan, UMR 5797, Gradignan, 33175 (France)

    2009-12-10

    An interesting new high-energy pulsar sub-population is emerging following early discoveries of gamma-ray millisecond pulsars (MSPs) by the Fermi Large Area Telescope (LAT). We present results from three-dimensional emission modeling, including the special relativistic effects of aberration and time-of-flight delays and also rotational sweepback of B-field lines, in the geometric context of polar cap (PC), outer gap (OG), and two-pole caustic (TPC) pulsar models. In contrast to the general belief that these very old, rapidly rotating neutron stars (NSs) should have largely pair-starved magnetospheres due to the absence of significant pair production, we find that most of the light curves are best fit by TPC and OG models, which indicates the presence of narrow accelerating gaps limited by robust pair production-even in these pulsars with very low spin-down luminosities. The gamma-ray pulse shapes and relative phase lags with respect to the radio pulses point to high-altitude emission being dominant for all geometries. We also find exclusive differentiation of the current gamma-ray MSP population into two MSP sub-classes: light curve shapes and lags across wavebands impose either pair-starved PC (PSPC) or TPC/OG-type geometries. In the first case, the radio pulse has a small lag with respect to the single gamma-ray pulse, while the (first) gamma-ray peak usually trails the radio by a large phase offset in the latter case. Finally, we find that the flux correction factor as a function of magnetic inclination and observer angles is typically of order unity for all models. Our calculation of light curves and flux correction factor for the case of MSPs is therefore complementary to the 'ATLAS paper' of Watters et al. for younger pulsars.

  14. Conceptual Design Gamma-Ray Large Area Space Telescope (GLAST) Tower Structure

    SciTech Connect (OSTI)

    Jennings, Chad

    2002-07-18

    The main objective of this work was to develop a conceptual design and engineering prototype for the Gamma-ray Large Area Space Telescope (GLAST) tower structure. This thesis describes the conceptual design of a GLAST tower and the fabrication and testing of a prototype tower tray. The requirements were that the structure had to support GLAST's delicate silicon strip detector array through ground handling, launch and in orbit operations as well as provide for thermal and electrical pathways. From the desired function and the given launch vehicle for the spacecraft that carries the GLAST detector, an efficient structure was designed which met the requirements. This thesis developed in three stages: design, fabrication, and testing. During the first stage, a general set of specifications was used to develop the initial design, which was then analyzed and shown to meet or exceed the requirements. The second stage called for the fabrication of prototypes to prove manufacturability and gauge cost and time estimates for the total project. The last step called for testing the prototypes to show that they performed as the analysis had shown and prove that the design met the requirements. As a spacecraft engineering exercise, this project required formulating a solution based on engineering judgment, analyzing the solution using advanced engineering techniques, then proving the validity of the design and analysis by the manufacturing and testing of prototypes. The design described here met all the requirements set out by the needs of the experiment and operating concerns. This strawman design is not intended to be the complete or final design for the GLAST instrument structure, but instead examines some of the main challenges involved and demonstrates that there are solutions to them. The purpose of these tests was to prove that there are solutions to the basic mechanical, electrical and thermal problems presented with the GLAST project.

  15. Jet emission in young radio sources: A Fermi large area telescope gamma-ray view

    SciTech Connect (OSTI)

    Migliori, G.; Siemiginowska, A.; Kelly, B. C.; Stawarz, ?.; Celotti, A.; Begelman, M. C.

    2014-01-10

    We investigate the contribution of the beamed jet component to the high-energy emission in young and compact extragalactic radio sources, focusing for the first time on the ?-ray band. We derive predictions on the ?-ray luminosities associated with the relativistic jet assuming a leptonic radiative model. The high-energy emission is produced via Compton scattering by the relativistic electrons in a spherical region at the considered scales (?10 kpc). Simulations show a wide range of ?-ray luminosities, with intensities up to ?10{sup 46}-10{sup 48} erg s{sup –1} depending on the assumed jet parameters. We find a highly linear relation between the simulated X-ray and ?-ray luminosities that can be used to select candidates for ?-ray detection. We compare the simulated luminosity distributions in the radio, X-ray, and ?-ray regimes with observations for the largest sample of X-ray-detected young radio quasars. Our analysis of ?4-yr Fermi Large Area Telescope (LAT) data does not yield any statistically significant detections. However, the majority of the model-predicted ?-ray fluxes for the sample are near or below the current Fermi-LAT flux threshold and compatible with the derived upper limits. Our study gives constraints on the minimum jet power (L {sub jet,} {sub kin}/L {sub disk} > 0.01) of a potential jet contribution to the X-ray emission in the most compact sources (? 1 kpc) and on the particle-to-magnetic field energy density ratio that are in broad agreement with equipartition assumptions.

  16. Fermi large area telescope detection of a break in the gamma-ray spectrum of the supernova remnant Cassiopeia A

    SciTech Connect (OSTI)

    Yuan, Yajie; Funk, Stefan; Lande, Joshua; Tibaldo, Luigi [W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States); Jóhannesson, Gülauger [Science Institute, University of Iceland, IS-107 Reykjavik (Iceland); Uchiyama, Yasunobu, E-mail: yuanyj@stanford.edu, E-mail: funk@slac.stanford.edu, E-mail: joshualande@gmail.com, E-mail: uchiyama@slac.stanford.edu [3-34-1 Nishi-Ikebukuro, Toshima-ku, Tokyo 171-8501 (Japan)

    2013-12-20

    We report on observations of the supernova remnant Cassiopeia A in the energy range from 100 MeV to 100 GeV using 44 months of observations from the Large Area Telescope on board the Fermi Gamma-Ray Space Telescope. We perform a detailed spectral analysis of this source and report on a low-energy break in the spectrum at 1.72{sub ?0.89}{sup +1.35} GeV. By comparing the results with models for the gamma-ray emission, we find that hadronic emission is preferred for the GeV energy range.

  17. Design and Initial Tests of the Tracker-Converter ofthe Gamma-ray Large Area Space Telescope

    SciTech Connect (OSTI)

    Atwood, W.B.; Bagagli, R.; Baldini, L.; Bellazzini, R.; Barbiellini, G.; Belli, F.; Borden, T.; Brez, A.; Brigida, M.; Caliandro, G.A.; Cecchi, C.; Cohen-Tanugi, J.; De Angelis, A.; Drell, P.; Favuzzi, C.; Fukazawa, Y.; Fusco, P.; Gargano, F.; Germani, S.; Giannitrapani, R.; Giglietto, N.; /UC, Santa Cruz /INFN, Pisa /Pisa U. /INFN, Trieste /INFN, Rome /Rome U.,Tor Vergata /SLAC /INFN, Bari /Bari U. /INFN, Perugia /Perugia U. /Udine U. /Hiroshima U. /NASA, Goddard /Maryland U. /Tokyo Inst. Tech. /INFN, Padua /Padua U. /Pisa, Scuola Normale Superiore

    2007-04-16

    The Tracker subsystem of the Large Area Telescope (LAT) science instrument of the Gamma-ray Large Area Space Telescope (GLAST) mission has been completed and tested. It is the central detector subsystem of the LAT and serves both to convert an incident gamma-ray into an electron-positron pair and to track the pair in order to measure the gamma-ray direction. It also provides the principal trigger for the LAT. The Tracker uses silicon strip detectors, read out by custom electronics, to detect charged particles. The detectors and electronics are packaged, along with tungsten converter foils, in 16 modular, high-precision carbon-composite structures. It is the largest silicon-strip detector system ever built for launch into space, and its aggressive design emphasizes very low power consumption, passive cooling, low noise, high efficiency, minimal dead area, and a structure that is highly transparent to charged particles. The test program has demonstrated that the system meets or surpasses all of its performance specifications as well as environmental requirements. It is now installed in the completed LAT, which is being prepared for launch in early 2008.

  18. The Fermi Large Area gamma ray Telescope and the current searches for dark matter in space

    E-Print Network [OSTI]

    Morselli, Aldo

    but there are competing astrophysical sources, such as pulsars, that can give a strong flux of primary positrons Gamma-ray Space Telescope, has detected the largest amount of gamma rays, in the 20MeV 300GeV energy and electrons (see [10], [11], [12], [13] and references therein). At energies between 100 GeV and 1 Te

  19. Fermi large area telescope observations of blazar 3C 279 occultations by the sun

    SciTech Connect (OSTI)

    Barbiellini, G.; Bastieri, D.; Buson, S.; Bechtol, K.; Blandford, R. D.; Borgland, A. W.; Buehler, R.; Cameron, R. A.; Chiang, J.; Bellazzini, R.; Bregeon, J.; Bruel, P.; Caraveo, P. A.; Cavazzuti, E.; Ciprini, S.; Cecchi, C.; Chaves, R. C. G.; Cheung, C. C. E-mail: phdmitry@stanford.edu; and others

    2014-04-01

    Observations of occultations of bright ?-ray sources by the Sun may reveal predicted pair halos around blazars and/or new physics, such as, e.g., hypothetical light dark matter particles—axions. We use Fermi Gamma-Ray Space Telescope (Fermi) data to analyze four occultations of blazar 3C 279 by the Sun on October 8 each year from 2008 to 2011. A combined analysis of the observations of these occultations allows a point-like source at the position of 3C 279 to be detected with significance of ?3?, but does not reveal any significant excess over the flux expected from the quiescent Sun. The likelihood ratio test rules out complete transparency of the Sun to the blazar ?-ray emission at a 3? confidence level.

  20. Simulating the High Energy Gamma-ray sky seen by the GLAST Large Area Telescope

    E-Print Network [OSTI]

    F. Longo; P. Azzi; D. Bastieri; G. Busetto; Y. Lei; R. Rando; O. Tibolla; L. Baldini; M. Kuss; L. Latronico; N. Omodei; M. Razzano; G. Spandre; P. Boinee; A. De Angelis; M. Frailis; M. Brigida; F. Gargano; N. Giglietto; F. Loparco; M. N. Mazziotta; C. Cecchi; P. Lubrano; F. Marcucci; M. Pepe; G. Tosti; A. Lionetto; A. Morselli; C. Pittori

    2005-03-24

    This paper presents the simulation of the GLAST high energy gamma-ray telescope. The simulation package, written in C++, is based on the Geant4 toolkit, and it is integrated into a general framework used to process events. A detailed simulation of the electronic signals inside Silicon detectors has been provided and it is used for the particle tracking, which is handled by a dedicated software. A unique repository for the geometrical description of the detector has been realized using the XML language and a C++ library to access this information has been designed and implemented. A new event display based on the HepRep protocol was implemented. The full simulation was used to simulate a full week of GLAST high energy gamma-ray observations. This paper outlines the contribution developed by the Italian GLAST software group.

  1. Bent-Tailed Radio Sources in the Australia Telescope Large Area Survey of the Chandra Deep Field-South

    E-Print Network [OSTI]

    Dehghan, Siamak; Franzen, Thomas M O; Norris, Ray P; Miller, Neal A

    2015-01-01

    Using the 1.4 GHz Australia Telescope Large Area Survey (ATLAS), supplemented with the 1.4 GHz Very Large Array images, we undertook a search for bent-tailed (BT) radio galaxies in the Chandra Deep Field-South (CDFS). Here we present a catalog of 56 detections, which include 45 bent-tailed sources, four diffuse low-surface-brightness objects (one relic, two halos, and one unclassified object), and a further seven complex, multi-component sources. We report BT sources with rest-frame powers in the range $10^{22} \\leq$ $\\textrm{P}_{1.4 \\textrm{ GHz}} \\leq 10^{26}$ W Hz$^{-1}$, redshifts up to 2 and linear extents from tens of kpc up to about one Mpc. This is the first systematic study of such sources down to such low powers and high redshifts and demonstrates the complementary nature of searches in deep, limited area surveys as compared to shallower, large surveys. Of the sources presented here one is the most distant bent-tailed source yet detected at a redshift of 2.1688. Two of the sources are found to be as...

  2. GRB 090926A AND BRIGHT LATE-TIME FERMI LARGE AREA TELESCOPE GAMMA-RAY BURST AFTERGLOWS

    SciTech Connect (OSTI)

    Swenson, C. A.; Roming, P. W. A.; Vetere, L.; Kennea, J. A. [Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States); Maxham, A.; Zhang, B. B.; Zhang, B. [University of Nevada, Las Vegas, Box 454002, 4505 Maryland Parkway, Las Vegas, NV 89154 (United States); Schady, P. [Max-Planck-Institut fuer extraterrestrische Physik, Garching (Germany); Holland, S. T. [Universities Space Research Association, 10227 Wincopin Circle, Suite 500, Columbia, MD 21044 (United States); Kuin, N. P. M.; Oates, S. R.; De Pasquale, M. [The UCL Mullard Space Science Laboratory, Holmbury St Mary, Surrey, RH5 6NT (United Kingdom); Page, K. L., E-mail: cswenson@astro.psu.ed [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom)

    2010-07-20

    GRB 090926A was detected by both the Gamma-ray Burst Monitor and Large Area Telescope (LAT) instruments on board the Fermi Gamma-ray Space Telescope. Swift follow-up observations began {approx}13 hr after the initial trigger. The optical afterglow was detected for nearly 23 days post trigger, placing it in the long-lived category. The afterglow is of particular interest due to its brightness at late times, as well as the presence of optical flares at T0+10{sup 5} s and later, which may indicate late-time central engine activity. The LAT has detected a total of 16 gamma-ray bursts; nine of these bursts, including GRB 090926A, also have been observed by Swift. Of the nine Swift-observed LAT bursts, six were detected by UVOT, with five of the bursts having bright, long-lived optical afterglows. In comparison, Swift has been operating for five years and has detected nearly 500 bursts, but has only seen {approx}30% of bursts with optical afterglows that live longer than 10{sup 5} s. We have calculated the predicted gamma-ray fluence, as would have been seen by the Burst Alert Telescope (BAT) on board Swift, of the LAT bursts to determine whether this high percentage of long-lived optical afterglows is unique, when compared to BAT-triggered bursts. We find that, with the exception of the short burst GRB 090510A, the predicted BAT fluences indicate that the LAT bursts are more energetic than 88% of all Swift bursts and also have brighter than average X-ray and optical afterglows.

  3. Timing Gamma-ray Pulsars with the Fermi Large Area Telescope: Timing Noise and Astrometry

    E-Print Network [OSTI]

    Kerr, Matthew; Johnston, Simon; Shannon, Ryan; Camilo, Fernando

    2015-01-01

    We have constructed timing solutions for 81 gamma-ray pulsars covering more than five years of Fermi data. The sample includes 37 radio-quiet or radio-faint pulsars which cannot be timed with other telescopes. These timing solutions and the corresponding pulse times of arrival are prerequisites for further study, e.g. phase-resolved spectroscopy or searches for mode switches. Many gamma-ray pulsars are strongly affected by timing noise, and we present a new method for characterizing the noise process and mitigating its effects on other facets of the timing model. We present an analysis of timing noise over the population using a new metric for characterizing its strength and spectral shape, namely its time-domain correlation. The dependence of the strength on spin frequency and spin-down rate is in good agreement with previous studies. We find that noise process power spectra $S(f)$ for unrecycled pulsars are steep, with strong correlations over our entire data set and spectral indices $S(f)\\propto f^{-\\alpha...

  4. The Third Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope

    E-Print Network [OSTI]

    Ackermann, M; Atwood, W; Baldini, L; Ballet, J; Barbiellini, G; Bastieri, D; Gonzalez, J; Bellazzini, R; Bissaldi, E; Blandford, R; Bloom, E; Bonino, R; Bottacini, E; Brandt, T; Bregeon, J; Britto, R; Bruel, P; Buehler, R; Buson, S; Caliandro, G; Cameron, R; Caragiulo, M; Caraveo, P; Casandjian, J; Cavazzuti, E; Cecchi, C; Charles, E; Chekhtman, A; Cheung, C; Chiang, J; Chiaro, G; Ciprini, S; Claus, R; Cohen-Tanugi, J; Cominsky, L; Conrad, J; Cutini, S; D'Abrusco, R; D'Ammando, F; Angelis, A; Desiante, R; Digel, S; Venere, L; Drell, P; Favuzzi, C; Fegan, S; Ferrara, E; Finke, J; Focke, W; Franckowiak, A; Fuhrmann, L; Furniss, A; Fusco, P; Gargano, F; Gasparrini, D; Giglietto, N; Giommi, P; Giordano, F; Giroletti, M; Glanzman, T; Godfrey, G; Grenier, I; Grove, J; Guiriec, S; Hewitt, J W; Hill, A; Horan, D; J'ohannesson, G; Johnson, A; Johnson, W; Kataoka, J; Kuss, M; Mura, G; Larsson, S; Latronico, L; Leto, C; Li, J; Li, L; Longo, F; Loparco, F; Lott, B; Lovellette, M; Lubrano, P; Madejski, G; Mayer, M; Mazziotta, M; McEnery, J; Michelson, P; Mizuno, T; Moiseev, A; Monzani, M; Morselli, A; Moskalenko, I; Murgia, S; Nuss, E; Ohno, M; Ohsugi, T; Ojha, R; Omodei, N; Orienti, M; Orlando, E; Paggi, A; Paneque, D; Perkins, J; Pesce-Rollins, M; Piron, F; Pivato, G; Porter, T; Rain`o, S; Rando, R; Razzano, M; Razzaque, S; Reimer, A; Reimer, O; Romani, R; Salvetti, D; Schaal, M; Schinzel, F; Schulz, A; Sgr`o, C; Siskind, E; Sokolovsky, K; Spada, F; Spandre, G; Spinelli, P; Stawarz, L; Suson, D; Takahashi, H; Takahashi, T; Tanaka, Y; Thayer, J; Tibaldo, L; Torres, D; Torresi, E; Tosti, G; Troja, E; Uchiyama, Y; Vianello, G; Winer, B; Wood, K; Zimmer, S

    2015-01-01

    The third catalog of active galactic nuclei (AGNs) detected by the Fermi-LAT (3LAC) is presented. It is based on the third Fermi-LAT catalog (3FGL) of sources detected with a test statistic (TS) greater than 25, using the first 4 years of data. The 3LAC includes 1591 AGNs located at high Galactic latitudes (|b|>10{\\deg}), which is a 71% increase over the second catalog that was based on 2 years of data. There are 28 duplicate associations (two counterparts to the same gamma-ray source), thus 1563 of the 2192 high-latitude gamma-ray sources of the 3FGL catalog are AGNs. A very large majority of these AGNs (98%) are blazars. About half of the newly detected blazars are of unknown type, i.e., they lack spectroscopic information of sufficient quality to determine the strength of their emission lines. Based on their spectral properties, these sources are evenly split between FSRQs and BL~Lacs. The general properties of the 3LAC sample confirm previous findings from earlier catalogs, but some new subclasses (e.g., ...

  5. Bent-tailed radio sources in the australia telescope large area survey of the Chandra deep field south

    SciTech Connect (OSTI)

    Dehghan, S.; Johnston-Hollitt, M.; Franzen, T. M. O.; Norris, R. P.; Miller, N. A.

    2014-11-01

    Using the 1.4 GHz Australia Telescope Large Area Survey, supplemented by the 1.4 GHz Very Large Array images, we undertook a search for bent-tailed (BT) radio galaxies in the Chandra Deep Field South. Here we present a catalog of 56 detections, which include 45 BT sources, 4 diffuse low-surface-brightness objects (1 relic, 2 halos, and 1 unclassified object), and a further 7 complex, multi-component sources. We report BT sources with rest-frame powers in the range 10{sup 22} ? P {sub 1.4} {sub GHz} ? 10{sup 26} W Hz{sup –1}, with redshifts up to 2 and linear extents from tens of kiloparsecs up to about 1 Mpc. This is the first systematic study of such sources down to such low powers and high redshifts and demonstrates the complementary nature of searches in deep, limited area surveys as compared to shallower, large surveys. Of the sources presented here, one is the most distant BT source yet detected at a redshift of 2.1688. Two of the sources are found to be associated with known clusters: a wide-angle tail source in A3141 and a putative radio relic which appears at the infall region between the galaxy group MZ 00108 and the galaxy cluster AMPCC 40. Further observations are required to confirm the relic detection, which, if successful, would demonstrate this to be the least powerful relic yet seen with P {sub 1.4} {sub GHz} = 9 × 10{sup 22} W Hz{sup –1}. Using these data, we predict future 1.4 GHz all-sky surveys with a resolution of ?10 arcsec and a sensitivity of 10 ?Jy will detect of the order of 560,000 extended low-surface-brightness radio sources of which 440,000 will have a BT morphology.

  6. Updated Search for Spectral Lines from Galactic Dark Matter Interactions with Pass 8 Data from the Fermi Large Area Telescope

    E-Print Network [OSTI]

    ,

    2015-01-01

    Dark matter in the Milky Way may annihilate directly into gamma rays, producing a monoenergetic spectral line. Therefore, detecting such a signature would be strong evidence for dark matter annihilation or decay. We search for spectral lines in the Fermi Large Area Telescope observations of the Milky Way halo in the energy range 200 MeV to 500 GeV using analysis methods from our most recent line searches. The main improvements relative to previous works are our use of 5.8 years of data reprocessed with the Pass 8 event-level analysis and the additional data resulting from the modified observing strategy designed to increase exposure of the Galactic center region. We searched in five sky regions selected to optimize sensitivity to different theoretically-motivated dark matter scenarios and find no significant detections. In addition to presenting the results from our search for lines, we also investigate the previously reported tentative detection of a line at 133 GeV using the new Pass 8 data.

  7. Constraining Dark Matter Models from a Combined Analysis of Milky Way Satellites with the Fermi Large Area Telescope

    SciTech Connect (OSTI)

    Ackermann, M.; Ajello, M.; /Stanford U., HEPL /Taiwan, Natl. Taiwan U. /SLAC; Albert, A.; /Taiwan, Natl. Taiwan U. /Ohio State U.; Atwood, W.B.; /UC, Santa Cruz; Baldini, L.; /INFN, Pisa; Ballet, J.; /DAPNIA, Saclay; Barbiellini, G.; /INFN, Trieste /Trieste U.; Bastieri, D.; /INFN, Padua /Padua U.; Bechtol, K.; /Stanford U., HEPL /Taiwan, Natl. Taiwan U. /SLAC; Bellazzini, R.; /INFN, Pisa; Berenji, B.; Blandford, R.D.; Bloom, E.D.; /Stanford U., HEPL /Taiwan, Natl. Taiwan U. /SLAC; Bonamente, E.; /INFN, Perugia /Perugia U.; Borgland, A.W.; /Stanford U., HEPL /Taiwan, Natl. Taiwan U. /SLAC; Bregeon, J.; /INFN, Pisa; Brigida, M.; /Bari Polytechnic /INFN, Bari; Bruel, P.; /Ecole Polytechnique; Buehler, R.; /Stanford U., HEPL /Taiwan, Natl. Taiwan U. /SLAC; Burnett, T.H.; /Washington U., Seattle; Buson, S.; /INFN, Padua /Padua U. /ICE, Bellaterra /Stanford U., HEPL /Taiwan, Natl. Taiwan U. /SLAC /INFN, Rome /Rome U. /IASF, Milan /IASF, Milan /DAPNIA, Saclay /INFN, Perugia /Perugia U. /Stanford U., HEPL /Taiwan, Natl. Taiwan U. /SLAC /Artep Inc. /Stanford U., HEPL /Taiwan, Natl. Taiwan U. /SLAC /ASDC, Frascati /Perugia U. /Stanford U., HEPL /Taiwan, Natl. Taiwan U. /SLAC /Montpellier U. /Stockholm U. /Stockholm U., OKC /ASDC, Frascati /ASDC, Frascati /Udine U. /INFN, Trieste /Bari Polytechnic /INFN, Bari /Naval Research Lab, Wash., D.C. /Stanford U., HEPL /Taiwan, Natl. Taiwan U. /SLAC /Montpellier U. /Bari Polytechnic /INFN, Bari /Ecole Polytechnique /NASA, Goddard /Hiroshima U. /Stanford U., HEPL /Taiwan, Natl. Taiwan U. /SLAC /Bari Polytechnic /INFN, Bari /INFN, Bari /ASDC, Frascati /NASA, Goddard /INFN, Perugia /Perugia U. /Bari Polytechnic /INFN, Bari /Bologna Observ. /Stanford U., HEPL /Taiwan, Natl. Taiwan U. /SLAC /DAPNIA, Saclay /Alabama U., Huntsville; /more authors..

    2012-09-14

    Satellite galaxies of the Milky Way are among the most promising targets for dark matter searches in gamma rays. We present a search for dark matter consisting of weakly interacting massive particles, applying a joint likelihood analysis to 10 satellite galaxies with 24 months of data of the Fermi Large Area Telescope. No dark matter signal is detected. Including the uncertainty in the dark matter distribution, robust upper limits are placed on dark matter annihilation cross sections. The 95% confidence level upper limits range from about 10{sup -26} cm{sup 3} s{sup -1} at 5 GeV to about 5 x 10{sup -23} cm{sup 3} s{sup -1} at 1 TeV, depending on the dark matter annihilation final state. For the first time, using gamma rays, we are able to rule out models with the most generic cross section ({approx}3 x 10{sup -26} cm{sup 3} s{sup -1} for a purely s-wave cross section), without assuming additional boost factors.

  8. DISCOVERY OF NINE GAMMA-RAY PULSARS IN FERMI LARGE AREA TELESCOPE DATA USING A NEW BLIND SEARCH METHOD

    SciTech Connect (OSTI)

    Pletsch, H. J.; Allen, B.; Aulbert, C.; Fehrmann, H.; Guillemot, L.; Kramer, M.; Barr, E. D.; Champion, D. J.; Eatough, R. P.; Freire, P. C. C.; Ray, P. S.; Belfiore, A.; Dormody, M.; Camilo, F.; Caraveo, P. A.; Celik, Oe.; Ferrara, E. C.; Hessels, J. W. T.; Keith, M.; Kerr, M. E-mail: guillemo@mpifr-bonn.mpg.de; and others

    2012-01-10

    We report the discovery of nine previously unknown gamma-ray pulsars in a blind search of data from the Fermi Large Area Telescope (LAT). The pulsars were found with a novel hierarchical search method originally developed for detecting continuous gravitational waves from rapidly rotating neutron stars. Designed to find isolated pulsars spinning at up to kHz frequencies, the new method is computationally efficient and incorporates several advances, including a metric-based gridding of the search parameter space (frequency, frequency derivative, and sky location) and the use of photon probability weights. The nine pulsars have spin frequencies between 3 and 12 Hz, and characteristic ages ranging from 17 kyr to 3 Myr. Two of them, PSRs J1803-2149 and J2111+ 4606, are young and energetic Galactic-plane pulsars (spin-down power above 6 Multiplication-Sign 10{sup 35} erg s{sup -1} and ages below 100 kyr). The seven remaining pulsars, PSRs J0106+4855, J0622+3749, J1620-4927, J1746-3239, J2028+3332, J2030+4415, and J2139+4716, are older and less energetic; two of them are located at higher Galactic latitudes (|b| > 10 Degree-Sign ). PSR J0106+4855 has the largest characteristic age (3 Myr) and the smallest surface magnetic field (2 Multiplication-Sign 10{sup 11} G) of all LAT blind-search pulsars. PSR J2139+4716 has the lowest spin-down power (3 Multiplication-Sign 10{sup 33} erg s{sup -1}) among all non-recycled gamma-ray pulsars ever found. Despite extensive multi-frequency observations, only PSR J0106+4855 has detectable pulsations in the radio band. The other eight pulsars belong to the increasing population of radio-quiet gamma-ray pulsars.

  9. Measurement of the Cosmic Ray e+ plus e- spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope

    E-Print Network [OSTI]

    Fermi/LAT Collaboration

    2009-04-30

    Designed as a high-sensitivity gamma-ray observatory, the Fermi Large Area Telescope is also an electron detector with a large acceptance exceeding 2m^2 sr at 300 GeV. Building on the gamma-ray analysis, we have developed an efficient electron detection strategy which provides sufficient background rejection for measurement of the steeply-falling electron spectrum up to 1 TeV. Our high precision data show that the electron spectrum falls with energy as E^(-3.0) and does not exhibit prominent spectral features. Interpretations in terms of a conventional diffusive model as well as a potential local extra component are briefly discussed.

  10. Large aperture diffractive space telescope

    DOE Patents [OSTI]

    Hyde, Roderick A. (Livermore, CA)

    2001-01-01

    A large (10's of meters) aperture space telescope including two separate spacecraft--an optical primary objective lens functioning as a magnifying glass and an optical secondary functioning as an eyepiece. The spacecraft are spaced up to several kilometers apart with the eyepiece directly behind the magnifying glass "aiming" at an intended target with their relative orientation determining the optical axis of the telescope and hence the targets being observed. The objective lens includes a very large-aperture, very-thin-membrane, diffractive lens, e.g., a Fresnel lens, which intercepts incoming light over its full aperture and focuses it towards the eyepiece. The eyepiece has a much smaller, meter-scale aperture and is designed to move along the focal surface of the objective lens, gathering up the incoming light and converting it to high quality images. The positions of the two space craft are controlled both to maintain a good optical focus and to point at desired targets which may be either earth bound or celestial.

  11. Adaptive Optics for Large Telescopes

    SciTech Connect (OSTI)

    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.

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

    E-Print Network [OSTI]

    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 Canary island of La Palma (Spain). In this talk we will outline the technical solutions adopted to fulfill the design requirem...

  13. Active Optics in Modern, Large Optical Telescopes

    E-Print Network [OSTI]

    Lothar Noethe

    2001-11-07

    Active optics is defined as the control of the shape and the alignment of the components of an optical system at low temporal frequencies. For modern large telescopes with flexible monolithic or segmented primary mirrors and also flexible structures this technique is indispensable to reach a performance which is either diffraction limited for an operation in space or limited by the atmosphere for an operation on the ground. This article first describes the theory of active optics, both of the wavefront analysis and the correction mechanisms, then the design of three representative active optics systems, two in telescopes of the four and eight meter class with meniscus mirrors and one in a telescope with a segmented primary mirror, and, finally, presents practical experience with these active optics systems.

  14. Large Area Vacuum Deposited Coatings

    SciTech Connect (OSTI)

    Martin, Peter M.

    2003-04-30

    It's easy to make the myriad of types of large area and decorative coatings for granted. We probably don't even think about most of them; the low-e and heat mirror coatings on our windows and car windows, the mirrors in displays, antireflection coatings on windows and displays, protective coatings on aircraft windows, heater coatings on windshields and aircraft windows, solar reflectors, thin film solar cells, telescope mirrors, Hubble mirrors, transparent conductive coatings, and the list goes on. All these products require large deposition systems and chambers. Also, don't forget that large batches of small substrates or parts are coated in large chambers. In order to be cost effective hundreds of ophthalmic lenses, automobile reflectors, display screens, lamp reflectors, cell phone windows, laser reflectors, DWDM filters, are coated in batches.

  15. Large fully retractable telescope enclosures still closable in strong wind

    E-Print Network [OSTI]

    Rutten, Rob

    are too small to deteriorate the image in normal observing situations with wind speeds up to 20 mLarge fully retractable telescope enclosures still closable in strong wind Felix C.M. Bettonvil a the telescopes are in operation. The telescopes and enclosures also operate in hard wind. The prototypes

  16. Early science with the large millimeter telescope: exploring...

    Office of Scientific and Technical Information (OSTI)

    Early science with the large millimeter telescope: exploring the effect of AGN activity on the relationships between molecular gas, dust, and star formation Citation Details...

  17. The Optical System for the Large Size Telescope of the Cherenkov Telescope Array

    E-Print Network [OSTI]

    Hayashida, M; Teshima, M; de Almeida, U Barres; Chikawa, M; Cho, N; Fukami, S; Gadola, A; Hanabata, Y; Horns, D; Jablonski, C; Katagiri, H; Kagaya, M; Ogino, M; Okumura, A; Saito, T; Stadler, R; Steiner, S; Straumann, U; Vollhardt, A; Wetteskind, H; Yamamoto, T; Yoshida, T

    2015-01-01

    The Large Size Telescope (LST) of the Cherenkov Telescope Array (CTA) is designed to achieve a threshold energy of 20 GeV. The LST optics is composed of one parabolic primary mirror 23 m in diameter and 28 m focal length. The reflector dish is segmented in 198 hexagonal, 1.51 m flat to flat mirrors. The total effective reflective area, taking into account the shadow of the mechanical structure, is about 368 m$^2$. The mirrors have a sandwich structure consisting of a glass sheet of 2.7 mm thickness, aluminum honeycomb of 60 mm thickness, and another glass sheet on the rear, and have a total weight about 47 kg. The mirror surface is produced using a sputtering deposition technique to apply a 5-layer coating, and the mirrors reach a reflectivity of $\\sim$94% at peak. The mirror facets are actively aligned during operations by an active mirror control system, using actuators, CMOS cameras and a reference laser. Each mirror facet carries a CMOS camera, which measures the position of the light spot of the optical ...

  18. Silicon Photomultiplier Research and Development Studies for the Large Size Telescope of the Cherenkov Telescope Array

    E-Print Network [OSTI]

    Rando, Riccardo; 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; Manea, Christian; Mariotti, Mosè; Mazin, Daniel; Mehrez, Fatima; Mirzoyan, Razmik; Podkladkin, Sergey; Reichardt, Ignasi; Rhode, Wolfgang; Rosier, Sylvie; Schultz, Cornelia; Stella, Carlo; Teshima, Masahiro; Wetteskind, Holger; Zavrtanik, Marko

    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 265 photodetector clusters; each will include seven photomultiplier tubes (PMTs), with an entrance window of 1.5 inches in diameter. The PMT design is based on mature and reliable technology. Recently, silicon photomultipliers (SiPMs) are emerging as a competitor. Currently, SiPMs have advantages (e.g. lower operating voltage and tolerance to high illumination levels) and disadvantages (e.g. higher capacitance and cross talk rates), but this technology is still young and rapidly evolving. SiPM technology has a strong pot...

  19. Cosmological Questions for the European Southern Observatory Very Large Telescope

    E-Print Network [OSTI]

    David Tytler

    1996-08-12

    The next decade promises an observational revolution which will change cosmology forever. The precise measurement of the angular anisotropy of the cosmic microwave background should specify to a few percent all of the parameters of the cosmological model which effect astrophysics. The growth of structure will then be determined (but not yet observed) until gravitational collapse becomes highly non-linear and stars, galaxies and active galactic nuclei (AGN) form. These processes are hard to model with basic physics because they are complex and allow a rich variety of expression. Instead observations will determine when the first stars and quasars formed, and how and when galaxies assembled. If we can reconcile the numerous contradictions which characterize the subject today, cosmology will become a mature subject, founded on the agreement between detailed, inclusive and realistic models, which make precise predictions, and the wealth of new data which will come from a wide variety of observations, at all wavelengths. This is an ambitious schedule, but nothing less is worthy of the outstanding capabilities of the 8 -- 10 m telescopes, the next generation space telescope, the opportunities at millimeterto sub-millimeter wavelengths and advanced computer modeling. The ESO Very Large Telescope (VLT) should play a major role in this revolution.

  20. VERITAS: Very LArge Energetic Radiation Imaging Telescope Array System

    E-Print Network [OSTI]

    T. C. Weekes; C. Akerlof; S. Biller; A. C. Breslin; J. H. Buckley; D. A. Carter-Lewis; M. Catanese; M. F. Cawley; B. Dingus; G. G. Fazio; D. J. Fegan; J. Finley; G. Fishman; J. Gaidos; G. H. Gillanders; P. Gorham; J. E. Grindlay; A. M. Hillas; J. Huchra; P. Kaaret; M. Kertzman; D. Kieda; F. Krennrich; R. C. Lamb; M. J. Lang; A. P. Marscher; S. Matz; T. McKay; D. Muller; R. Ong; W. Purcell; J. Rose; G. Sembroski; F. D. Seward; P. Slane; S. Swordy; T. Tumer; M. Ulmer; M. Urban; B. J. Wilkes

    1997-06-15

    A next generation atmospheric Cherenkov observatory is described based on the Whipple Observatory $\\gamma$-ray telescope. A total of nine such imaging telescopes will be deployed in an array that will permit the maximum versatility and give high sensitivity in the 50 GeV - 50 TeV band (with maximum sensitivity from 100 GeV to 10 TeV).

  1. Fast minimum variance wavefront reconstruction for extremely large telescopes

    E-Print Network [OSTI]

    Eric Thiebaut; Michel Tallon

    2010-03-01

    We present a new algorithm, FRiM (FRactal Iterative Method), aiming at the reconstruction of the optical wavefront from measurements provided by a wavefront sensor. As our application is adaptive optics on extremely large telescopes, our algorithm was designed with speed and best quality in mind. The latter is achieved thanks to a regularization which enforces prior statistics. To solve the regularized problem, we use the conjugate gradient method which takes advantage of the sparsity of the wavefront sensor model matrix and avoids the storage and inversion of a huge matrix. The prior covariance matrix is however non-sparse and we derive a fractal approximation to the Karhunen-Loeve basis thanks to which the regularization by Kolmogorov statistics can be computed in O(N) operations, N being the number of phase samples to estimate. Finally, we propose an effective preconditioning which also scales as O(N) and yields the solution in 5-10 conjugate gradient iterations for any N. The resulting algorithm is therefore O(N). As an example, for a 128 x 128 Shack-Hartmann wavefront sensor, FRiM appears to be more than 100 times faster than the classical vector-matrix multiplication method.

  2. Large Synoptic Survey Telescope: Dark Energy Science Collaboration

    E-Print Network [OSTI]

    LSST Dark Energy Science Collaboration

    2012-11-01

    This white paper describes the LSST Dark Energy Science Collaboration (DESC), whose goal is the study of dark energy and related topics in fundamental physics with data from the Large Synoptic Survey Telescope (LSST). It provides an overview of dark energy science and describes the current and anticipated state of the field. It makes the case for the DESC by laying out a robust analytical framework for dark energy science that has been defined by its members and the comprehensive three-year work plan they have developed for implementing that framework. The analysis working groups cover five key probes of dark energy: weak lensing, large scale structure, galaxy clusters, Type Ia supernovae, and strong lensing. The computing working groups span cosmological simulations, galaxy catalogs, photon simulations and a systematic software and computational framework for LSST dark energy data analysis. The technical working groups make the connection between dark energy science and the LSST system. The working groups have close linkages, especially through the use of the photon simulations to study the impact of instrument design and survey strategy on analysis methodology and cosmological parameter estimation. The white paper describes several high priority tasks identified by each of the 16 working groups. Over the next three years these tasks will help prepare for LSST analysis, make synergistic connections with ongoing cosmological surveys and provide the dark energy community with state of the art analysis tools. Members of the community are invited to join the LSST DESC, according to the membership policies described in the white paper. Applications to sign up for associate membership may be made by submitting the Web form at http://www.slac.stanford.edu/exp/lsst/desc/signup.html with a short statement of the work they wish to pursue that is relevant to the LSST DESC.

  3. Laser guide star projection for large telescopes Erez N. Ribak

    E-Print Network [OSTI]

    Ribak, Erez

    this projected pattern. Keywords: adaptive optics, laser guide stars 1. INTRODUCTION Telescopes of diameter will be corrected by active and adaptive optics, to remedy slow and fast variations of the optics beam diameter is set by the turbulence distorting the beam going up. Most systems use the light

  4. New strategies for an extremely large telescope dedicated to extremely high contrast: The Colossus Project**

    E-Print Network [OSTI]

    Berdyugina, Svetlana

    New strategies for an extremely large telescope dedicated to extremely high contrast: The Colossus and adaptive optics and cophasing for the designing and for building such dedicated to extremely high contrast

  5. Prospects for GRB Science with the Fermi Large Area Telescope

    E-Print Network [OSTI]

    Band, D L; Baldini, L; Barbiellini, G; Baring, M G; Bastieri, D; Battelino, M; Bellazzini, R; Bissaldi, E; Bogaert, G; Bonnel, J; Chiang, J; Cohen-Tanugi, J; Connaughton, V; Cutini, S; de Palma, F; Dingus, B L; Silva, E do Couto e; Fishman, G; Galli, A; Gehrels, N; Giglietto, N; Granot, J; Guiriec, S; Hughes, R E; Kamae, T; Komin, N; Kühn, F; Kuss, M; Longo, F; Lubrano, P; Kippen, R M; Mazziotta, M N; McEnery, J E; McGlynn, S; Moretti, E; Nakamori, T; Norris, J P; Ohno, M; Olivo, M; Omodei, N; Pelassa, V; Piron, F; Preece, R; Razzano, M; Russell, J J; Ryde, F; Parkinson, P M Saz; Scargle, J D; Sgrò, C; Shimokawabe, T; Smith, P D; Spandre, G; Spinelli, P; Stamatikos, M; Winer, B L; Yamazaki, R

    2009-01-01

    The LAT instrument on the Fermi mission will reveal the rich spectral and temporal gamma-ray burst phenomena in the > 100 MeV band. The synergy with Fermi's GBM detectors will link these observations to those in the well explored 10-1000 keV range; the addition of the > 100 MeV band observations will resolve theoretical uncertainties about burst emission in both the prompt and afterglow phases. Trigger algorithms will be applied to the LAT data both onboard the spacecraft and on the ground. The sensitivity of these triggers will differ because of the available computing resources onboard and on the ground. Here we present the LAT's burst detection methodologies and the instrument's GRB capabilities.

  6. Development of the photomultiplier tube readout system for the first Large-Sized Telescope of the Cherenkov Telescope Array

    E-Print Network [OSTI]

    Masuda, Shu; Barrio, Juan Abel; Bigas, Oscar Blanch; Delgado, Carlos; Coromina, Lluís Freixas; Gunji, Shuichi; Hadasch, Daniela; Hatanaka, Kenichiro; Ikeno, Masahiro; Laguna, Jose Maria Illa; Inome, Yusuke; Ishio, Kazuma; Katagiri, Hideaki; Kubo, Hidetoshi; Martínez, Gustavo; Mazin, Daniel; Nakajima, Daisuke; Nakamori, Takeshi; Ohoka, Hideyuki; Paoletti, Riccardo; Ritt, Stefan; Rugliancich, Andrea; Saito, Takayuki; Sulanke, Karl-Heinz; Takeda, Junki; Tanaka, Manobu; Tanigawa, Shunsuke; Tejedor, Luis Ángel; Teshima, Masahiro; Tsuchiya, Yugo; Uchida, Tomohisa; Yamamoto, Tokonatsu

    2015-01-01

    The Cherenkov Telescope Array (CTA) is the next generation ground-based very high energy gamma-ray observatory. The Large-Sized Telescope (LST) of CTA targets 20 GeV -- 1 TeV gamma rays and has 1855 photomultiplier tubes (PMTs) installed in the focal plane camera. With the 23 m mirror dish, the night sky background (NSB) rate amounts to several hundreds MHz per pixel. In order to record clean images of gamma-ray showers with minimal NSB contamination, a fast sampling of the signal waveform is required so that the signal integration time can be as short as the Cherenkov light flash duration (a few ns). We have developed a readout board which samples waveforms of seven PMTs per board at a GHz rate. Since a GHz FADC has a high power consumption, leading to large heat dissipation, we adopted the analog memory ASIC "DRS4". The sampler has 1024 capacitors per channel and can sample the waveform at a GHz rate. Four channels of a chip are cascaded to obtain deeper sampling depth with 4096 capacitors. After a trigger ...

  7. Design of a prototype device to calibrate the Large Size Telescope camera of the Cherenkov Telescope Array

    E-Print Network [OSTI]

    Iori, M; De Persio, F; Chatterjee, A; Ferrarotto, F; Nagesh, B K; Saha, L; Singh, B B

    2015-01-01

    The Cherenkov Telescope Array is a project that aims to exploring the highest energy region of electromagnetic spectrum. Two arrays, one for each hemisphere, will cover the full sky in a range from few tens of GeV to hundreds of TeV improving the sensitivity and angular resolution of the present operating arrays. A prototype of the Large Size Telescope (LST) for the study of gamma ray astronomy above some tens of GeV will be installed at the Canary Island of La Palma in 2016. The LST camera, made by an array of photomultipliers (PMTs), requires an accurate and systematic calibration over a wide dynamic range. In this contribution, we present an optical calibration system made by a 355 nm wavelength laser with 400 ps pulse width, 1 muJ output energy, up to 4k Hz repetition rate and a set of neutral density filters to obtain a wide range of photon intensities, up to 1000 photoelectrons/PMT, to be sent to the camera plane 28 m away. The number of photons after the diffuser of the calibration box, located in the ...

  8. Synergy between the Large Synoptic Survey Telescope and the Square Kilometre Array

    E-Print Network [OSTI]

    McEwen, Jason

    Synergy between the Large Synoptic Survey Telescope and the Square Kilometre Array David Bacon1 waveband, and the time resolution of the SKA. Advancing Astrophysics with the Square Kilometre Array June 8 provide an overview of the science benefits of combining information from the Square Kilo- metre Array

  9. Airbrushed Nickel Nanoparticles for Large-Area

    SciTech Connect (OSTI)

    Sarac, Mehmet; ANDERSON, BRYAN; Pearce, Ryan; Railsback, Justin; Oni, Adedapo; White, Ryan M.; Hensley, Dale K; Lebeau, James M; Melechko, Anatoli; Tracy, Joseph B

    2013-01-01

    Vertically aligned carbon nanofibers (VACNFs) were grown by plasma-enhanced chemical vapor deposition (PECVD) using Ni nanoparticle (NP) catalysts that were deposited by airbrushing onto Si, Al, Cu, and Ti substrates. Airbrushing is a simple method for depositing catalyst NPs over large areas that is compatible with roll-to-roll processing. The distribution and morphology of VACNFs are affected by the airbrushing parameters and the composition of the metal foil. Highly concentrated Ni NPs in heptane give more uniform distributions than pentane and hexanes, resulting in more uniform coverage of VACNFs. For VACNF growth on metal foils, Si micropowder was added as a precursor for Si-enriched coatings formed in situ on the VACNFs that impart mechanical rigidity. Interactions between the catalyst NPs and the metal substrates impart control over the VACNF morphology. Growth of carbon nanostructures on Cu is particularly noteworthy because the miscibility of Ni with Cu poses challenges for VACNF growth, and carbon nanostructures anchored to Cu substrates are desired as anode materials for Li-ion batteries and for thermal interface materials.

  10. Large area atmospheric-pressure plasma jet

    DOE Patents [OSTI]

    Selwyn, Gary S. (Los Alamos, NM); Henins, Ivars (Los Alamos, NM); Babayan, Steve E. (Huntington Beach, CA); Hicks, Robert F. (Los Angeles, CA)

    2001-01-01

    Large area atmospheric-pressure plasma jet. A plasma discharge that can be operated at atmospheric pressure and near room temperature using 13.56 MHz rf power is described. Unlike plasma torches, the discharge produces a gas-phase effluent no hotter than 250.degree. C. at an applied power of about 300 W, and shows distinct non-thermal characteristics. In the simplest design, two planar, parallel electrodes are employed to generate a plasma in the volume therebetween. A "jet" of long-lived metastable and reactive species that are capable of rapidly cleaning or etching metals and other materials is generated which extends up to 8 in. beyond the open end of the electrodes. Films and coatings may also be removed by these species. Arcing is prevented in the apparatus by using gas mixtures containing He, which limits ionization, by using high flow velocities, and by properly spacing the rf-powered electrode. Because of the atmospheric pressure operation, there is a negligible density of ions surviving for a sufficiently long distance beyond the active plasma discharge to bombard a workpiece, unlike the situation for low-pressure plasma sources and conventional plasma processing methods.

  11. Synergy between the Large Synoptic Survey Telescope and the Square Kilometre Array

    E-Print Network [OSTI]

    Bacon, David; Abdalla, Filipe B; Brown, Michael; Bull, Philip; Camera, Stefano; Fender, Rob; Grainge, Keith; Ivezic, Zeljko; Jarvis, Matt; Jackson, Neal; Kirk, Donnacha; Mann, Bob; McEwen, Jason; McKean, John; Newman, Jeffrey A; Raccanelli, Alvise; Sahlen, Martin; Santos, Mario; Tyson, Anthony; Zhao, Gong-Bo

    2015-01-01

    We provide an overview of the science benefits of combining information from the Square Kilometre Array (SKA) and the Large Synoptic Survey Telescope (LSST). We first summarise the capabilities and timeline of the LSST and overview its science goals. We then discuss the science questions in common between the two projects, and how they can be best addressed by combining the data from both telescopes. We describe how weak gravitational lensing and galaxy clustering studies with LSST and SKA can provide improved constraints on the causes of the cosmological acceleration. We summarise the benefits to galaxy evolution studies of combining deep optical multi-band imaging with radio observations. Finally, we discuss the excellent match between one of the most unique features of the LSST, its temporal cadence in the optical waveband, and the time resolution of the SKA.

  12. Monte-Carlo modelling of multi-conjugate adaptive optics performance on the European Extremely Large Telescope

    E-Print Network [OSTI]

    Basden, Alastair

    2015-01-01

    The performance of a wide-field adaptive optics system depends on input design parameters. Here we investigate the performance of a multi-conjugate adaptive optics system design for the European Extremely Large Telescope, using an end-to-end Monte-Carlo adaptive optics simulation tool, DASP. We consider parameters such as the number of laser guide stars, sodium layer depth, wavefront sensor pixel scale, number of deformable mirrors, mirror conjugation and actuator pitch. We provide potential areas where costs savings can be made, and investigate trade-offs between performance and cost. We conclude that a 6 laser guide star system using 3 DMs seems to be a sweet spot for performance and cost compromise.

  13. Cosmology with the Very Large Telescope Interferometer using a space based astrometric reference frame

    E-Print Network [OSTI]

    David Tytler

    1997-01-26

    Cosmology with large interferometric telescopes is a rich and largely unexplored subject, involving three types of measurement: astrometric measurement of absolute distances and proper motions, dispersions of relative proper motions, and images. The ground based interferometers can have huge apertures, which are necessary for faint cosmological targets. But, alone, they are limited to astrometry within the isoplanatic patch, and hence to relative positions, which are of little use for parallaxes and proper motions because reference stars have unknown parallaxes and huge (500 \\mu arcsec) unknown motions. We propose that space missions should measure global astrometric parallaxes and proper motions for (V > 16) reference stars within the isoplanatic patches of important cosmological and Galactic targets. Ground based interferometers can then measure absolute distances (parallaxes) and proper motions to 10 \\mu arcsec, tied to these reference stars. But cosmological observations stretch the VLTI technically. To observe the few best targets, we need to be able to measure positions to 16) near to important targets. Most of the science is at 1 --2 microns, where excellent adaptive optics will be needed on the 8-m telescopes.

  14. First Results From the Large Binocular Telescope: Deep Photometry of New dSphs

    E-Print Network [OSTI]

    Matthew G. Coleman; Jelte de Jong

    2007-08-20

    This contribution describes photometry for two Galactic dSphs obtained with the Large Binocular Telescope to a magnitude of ~25.5. Using the Large Binocular Camera, a purpose-built wide-field imager for the LBT, we have examined the structure and star formation histories of two newly-discovered Local Group members, the Hercules dSph and the Leo T dSph/dIrr system. We have constructed a structural map for the Hercules system using three-filter photometry to V ~ 25.5. This is the first deep photometry for this system, and it indicates that Hercules is unusually elongated, possibly indicating distortion due to the Galactic tidal field. We have also derived the first star formation history for the Leo T system, and find that its oldest population of stars (age ~ 13 Gyr) were relatively metal-rich, with [Fe/H] ~ -1.5.

  15. Measurement of atmospheric neutrino oscillations with very large volume neutrino telescopes

    E-Print Network [OSTI]

    J. P. Yañez; A. Kouchner

    2015-09-28

    Neutrino oscillations have been probed during the last few decades using multiple neutrino sources and experimental set-ups. In the recent years, very large volume neutrino telescopes have started contributing to the field. First ANTARES and then IceCube have relied on large and sparsely instrumented volumes to observe atmospheric neutrinos for combinations of baselines and energies inaccessible to other experiments. Using this advantage, the latest result from IceCube starts approaching the precision of other established technologies, and is paving the way for future detectors, such as ORCA and PINGU. These new projects seek to provide better measurements of neutrino oscillation parameters, and eventually determine the neutrino mass ordering. The results from running experiments and the potential from proposed projects are discussed in this review, emphasizing the experimental challenges involved in the measurements.

  16. Measurement of atmospheric neutrino oscillations with very large volume neutrino telescopes

    E-Print Network [OSTI]

    Yañez, J P

    2015-01-01

    Neutrino oscillations have been probed during the last few decades using multiple neutrino sources and experimental set-ups. In the recent years, very large volume neutrino telescopes have started contributing to the field. First ANTARES and then IceCube have relied on large and sparsely instrumented volumes to observe atmospheric neutrinos for combinations of baselines and energies inaccessible to other experiments. Using this advantage, the latest result from IceCube starts approaching the precision of other established technologies, and is paving the way for future detectors, such as ORCA and PINGU. These new projects seek to provide better measurements of neutrino oscillation parameters, and eventually determine the neutrino mass ordering. The results from running experiments and the potential from proposed projects are discussed in this review, emphasizing the experimental challenges involved in the measurements.

  17. Development of Large Area Gas Electron Multiplier Detector and...

    Office of Scientific and Technical Information (OSTI)

    Development of Large Area Gas Electron Multiplier Detector and Its Application to a Digital Hadron Calorimeter for Future Collider Experiments Citation Details In-Document Search...

  18. Large area 3D helical photonic crystals A. K. Rauba)

    E-Print Network [OSTI]

    New Mexico, University of

    of helical structures (3D photonic crystals) using a simple, parallel, large-area lithography processLarge area 3D helical photonic crystals A. K. Rauba) and S. R. J. Brueckb) Center for High, enabling a high index contrast chiral meta- material. Optical transmission measurements of these helical

  19. Probabilistic Damage Detection Based on Large Area Electronics Sensing Sheets

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Probabilistic Damage Detection Based on Large Area Electronics Sensing Sheets Yao Yao and Branko-stage damage detection and characterization requires continuous sensing over large areas of structure are not sensitive to damage. In this research, a probabilistic approach based on Monte Carlo (MC) simulations

  20. Asteroid Discovery and Characterization with the Large Synoptic Survey Telescope (LSST)

    E-Print Network [OSTI]

    Jones, R Lynne; Ivezic, Zeljko

    2015-01-01

    The Large Synoptic Survey Telescope (LSST) will be a ground-based, optical, all-sky, rapid cadence survey project with tremendous potential for discovering and characterizing asteroids. With LSST's large 6.5m diameter primary mirror, a wide 9.6 square degree field of view 3.2 Gigapixel camera, and rapid observational cadence, LSST will discover more than 5 million asteroids over its ten year survey lifetime. With a single visit limiting magnitude of 24.5 in r-band, LSST will be able to detect asteroids in the Main Belt down to sub-kilometer sizes. The current strawman for the LSST survey strategy is to obtain two visits (each visit being a pair of back-to-back 15s exposures) per field, separated by about 30 minutes, covering the entire visible sky every 3-4 days throughout the observing season, for ten years. The catalogs generated by LSST will increase the known number of small bodies in the Solar System by a factor of 10-100 times, among all populations. The median number of observations for Main Belt aster...

  1. Indirect searches for dark matter with the Fermi large area telescopestar

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Albert, Andrea

    2015-01-01

    There is overwhelming evidence that non-baryonic dark matter constitutes ~ 27% of the energy density of the Universe. Weakly Interacting Massive Particles (WIMPs) are promising dark matter candidates that may produce ? rays via annihilation or decay detectable by the Fermi Large Area Telescope (LAT). A detection of WIMPs would also indicate the existence of physics beyond the Standard Model. We present recent results from the two cleanest indirect WIMP searches by the Fermi-LAT Collaboration: searches for ?-ray spectral lines and ?-ray emission associated with Milky Way dwarf spheroidal satellite galaxies.

  2. High Energy Large Area Surveys: optically obscured AGN and the history of accretion

    E-Print Network [OSTI]

    F. Fiore; the HELLAS2XMM collaboration

    2004-06-01

    Hard X-ray, large area surveys are a fundamental complement of ultra-deep, pencil beam surveys in obtaining a more complete coverage of the L-z plane, allowing to find luminous QSO in wide z ranges. Furthermore, results from these surveys can be used to make reliable predictions about the luminosity (and hence the redshift) of the sources in the deep surveys which have optical counterparts too faint to be observed with the present generation of optical telescopes. This allows us to obtain accurate luminosity functions on wide luminosity and redshift intervals.

  3. Finding Large Aperture Fractures in Geothermal Resource Areas...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    A Three-Component Long-Offset Surface Seismic Survey, PSInSAR, and Kinematic Analysis Finding Large Aperture Fractures in Geothermal Resource Areas Using A Three-Component...

  4. Large-area visually augmented navigation for autonomous underwater vehicles

    E-Print Network [OSTI]

    Eustice, Ryan M

    2005-01-01

    This thesis describes a vision-based, large-area, simultaneous localization and mapping (SLAM) algorithm that respects the low-overlap imagery constraints typical of autonomous underwater vehicles (AUVs) while exploiting ...

  5. Transferred metal electrode films for large-area electronic devices...

    Office of Scientific and Technical Information (OSTI)

    metal electrode films for large-area electronic devices The evaporation of metal-film gate electrodes for top-gate organic field-effect transistors (OFETs) limits the...

  6. EXPECTED LARGE SYNOPTIC SURVEY TELESCOPE (LSST) YIELD OF ECLIPSING BINARY STARS

    SciTech Connect (OSTI)

    Prsa, Andrej; Pepper, Joshua; Stassun, Keivan G.

    2011-08-15

    In this paper, we estimate the Large Synoptic Survey Telescope (LSST) yield of eclipsing binary stars, which will survey {approx}20,000 deg{sup 2} of the southern sky during a period of 10 years in six photometric passbands to r {approx} 24.5. We generate a set of 10,000 eclipsing binary light curves sampled to the LSST time cadence across the whole sky, with added noise as a function of apparent magnitude. This set is passed to the analysis-of-variance period finder to assess the recoverability rate for the periods, and the successfully phased light curves are passed to the artificial-intelligence-based pipeline ebai to assess the recoverability rate in terms of the eclipsing binaries' physical and geometric parameters. We find that, out of {approx}24 million eclipsing binaries observed by LSST with a signal-to-noise ratio >10 in mission lifetime, {approx}28% or 6.7 million can be fully characterized by the pipeline. Of those, {approx}25% or 1.7 million will be double-lined binaries, a true treasure trove for stellar astrophysics.

  7. NANO EXPRESS Fabrication of Large Area Periodic Nanostructures Using

    E-Print Network [OSTI]

    Mohseni, Hooman

    , such as photonic band-gap materials, high dense data storage, and photonic devices. We have developed a maskless areas, such as photonic band-gap materials [1], high dense data storage [2], and photonic devices [3NANO EXPRESS Fabrication of Large Area Periodic Nanostructures Using Nanosphere Photolithography

  8. A spectroscopic survey of WISE-selected obscured quasars with the southern african large telescope

    SciTech Connect (OSTI)

    Hainline, Kevin N.; Hickox, Ryan C.; Carroll, Christopher M. [Department of Physics and Astronomy, Dartmouth College, Hanover, NH 03755 (United States); Myers, Adam D.; DiPompeo, Michael A. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Trouille, Laura [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208, The Adler Planetarium, Chicago, IL 60605 (United States)

    2014-11-10

    We present the results of an optical spectroscopic survey of a sample of 40 candidate obscured quasars identified on the basis of their mid-infrared emission detected by the Wide-Field Infrared Survey Explorer (WISE). Optical spectra for this survey were obtained using the Robert Stobie Spectrograph on the Southern African Large Telescope. Our sample was selected with WISE colors characteristic of active galactic nuclei (AGNs), as well as red optical to mid-IR colors indicating that the optical/UV AGN continuum is obscured by dust. We obtain secure redshifts for the majority of the objects that comprise our sample (35/40), and find that sources that are bright in the WISE W4 (22 ?m) band are typically at moderate redshift ((z) = 0.35) while sources fainter in W4 are at higher redshifts ((z) = 0.73). The majority of the sources have narrow emission lines with optical colors and emission line ratios of our WISE-selected sources that are consistent with the locus of AGN on the rest-frame g – z color versus [Ne III] ?3869/[O II] ??3726+3729 line ratio diagnostic diagram. We also use empirical AGN and galaxy templates to model the spectral energy distributions (SEDs) for the objects in our sample, and find that while there is significant variation in the observed SEDs for these objects, the majority require a strong AGN component. Finally, we use the results from our analysis of the optical spectra and the SEDs to compare our selection criteria to alternate criteria presented in the literature. These results verify the efficacy of selecting luminous obscured AGNs based on their WISE colors.

  9. Plasma and Ion Sources in Large Area Coatings: A Review

    SciTech Connect (OSTI)

    Anders, Andre

    2005-02-28

    Efficient deposition of high-quality coatings often requires controlled application of excited or ionized particles. These particles are either condensing (film-forming) or assisting by providing energy and momentum to the film growth process, resulting in densification, sputtering/etching, modification of stress, roughness, texture, etc. In this review, the technical means are surveyed enabling large area application of ions and plasmas, with ion energies ranging from a few eV to a few keV. Both semiconductortype large area (single wafer or batch processing with {approx} 1000 cm{sup 2}) and in-line web and glass-coating-type large area (> 10{sup 7} m{sup 2} annually) are considered. Characteristics and differences between plasma and ion sources are explained. The latter include gridded and gridless sources. Many examples are given, including sources based on DC, RF, and microwave discharges, some with special geometries like hollow cathodes and E x B configurations.

  10. Semiconductor-based, large-area, flexible, electronic devices

    DOE Patents [OSTI]

    Goyal, Amit (Knoxville, TN)

    2011-03-15

    Novel articles and methods to fabricate the same resulting in flexible, large-area, triaxially textured, single-crystal or single-crystal-like, semiconductor-based, electronic devices are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  11. Large-area metallic photonic lattices for military applications.

    SciTech Connect (OSTI)

    Luk, Ting Shan

    2007-11-01

    In this project we developed photonic crystal modeling capability and fabrication technology that is scaleable to large area. An intelligent optimization code was developed to find the optimal structure for the desired spectral response. In terms of fabrication, an exhaustive survey of fabrication techniques that would meet the large area requirement was reduced to Deep X-ray Lithography (DXRL) and nano-imprint. Using DXRL, we fabricated a gold logpile photonic crystal in the <100> plane. For the nano-imprint technique, we fabricated a cubic array of gold squares. These two examples also represent two classes of metallic photonic crystal topologies, the connected network and cermet arrangement.

  12. Small Solutions to the Large Telescope Problem: A Massively Replicated MEMS Spectrograph

    E-Print Network [OSTI]

    Nicholas Konidaris; Joel Kubby; Andrew Sheinis

    2008-07-15

    In traditional seeing-limited observations the spectrograph aperture scales with telescope aperture, driving sizes and costs to enormous proportions. We propose a new solution to the seeing-limited spectrograph problem. A massively fiber-sliced configuration feeds a set of small diffraction-limited spectrographs. We present a prototype, tunable, J-band, diffraction grating, designed specifically for Astronomical applications: The grating sits at the heart of a spectrograph, no bigger than a few inches on a side. Throughput requirements dictate using tens-of-thousands of spectrographs on a single 10 to 30 meter telescope. A full system would cost significantly less than typical instruments on 10m or 30m telescopes.

  13. Large area, surface discharge pumped, vacuum ultraviolet light source

    DOE Patents [OSTI]

    Sze, Robert C. (Santa Fe, NM); Quigley, Gerard P. (Los Alamos, NM)

    1996-01-01

    Large area, surface discharge pumped, vacuum ultraviolet (VUV) light source. A contamination-free VUV light source having a 225 cm.sup.2 emission area in the 240-340 nm region of the electromagnetic spectrum with an average output power in this band of about 2 J/cm.sup.2 at a wall-plug efficiency of approximately 5% is described. Only ceramics and metal parts are employed in this surface discharge source. Because of the contamination-free, high photon energy and flux, and short pulse characteristics of the source, it is suitable for semiconductor and flat panel display material processing.

  14. Large area, surface discharge pumped, vacuum ultraviolet light source

    DOE Patents [OSTI]

    Sze, R.C.; Quigley, G.P.

    1996-12-17

    Large area, surface discharge pumped, vacuum ultraviolet (VUV) light source is disclosed. A contamination-free VUV light source having a 225 cm{sup 2} emission area in the 240-340 nm region of the electromagnetic spectrum with an average output power in this band of about 2 J/cm{sup 2} at a wall-plug efficiency of approximately 5% is described. Only ceramics and metal parts are employed in this surface discharge source. Because of the contamination-free, high photon energy and flux, and short pulse characteristics of the source, it is suitable for semiconductor and flat panel display material processing. 3 figs.

  15. A Large Area Detector proposed for the Large Observatory for X-ray Timing (LOFT)

    E-Print Network [OSTI]

    Zane, S; Kennedy, T; Feroci, M; Herder, J -W Den; Ahangarianabhari, M; Argan, A; Azzarello, P; Baldazzi, G; Barret, D; Bertuccio, G; Bodini, P; Bozzo, E; Cadoux, F; Cais, P; Campana, R; Coker, J; Cros, A; Del Monte, E; De Rosa, A; Di Cosimo, S; Donnarumma, I; Evangelista, Y; Favre, Y; Feldman, C; Fraser, G; Fuschino, F; Grassi, M; Hailey, M R; Hudec, R; Labanti, C; Macera, D; Malcovati, P; Marisaldi, M; Martindale, A; Mineo, T; Muleri, F; Nowak, M; Orlandini, M; Pacciani, L; Perinati, E; Petracek, V; Pohl, M; Rachevski, A; Smith, P; Santangelo, A; Seyler, J -Y; Schmid, C; Soffitta, P; Suchy, S; Tenzer, C; Uttley, P; Vacchi, A; Zampa, G; Zampa, N; Wilms, J; Winter, B

    2012-01-01

    The Large Observatory for X-ray Timing (LOFT) is one of the four candidate ESA M3 missions considered for launch in the 2022 time-frame. It is specifically designed to perform fast X-ray timing and probe the status of the matter near black holes and neutron stars. The LOFT scientific payload is composed of a Large Area Detector (LAD) and a Wide Field Monitor (WFM). The LAD is a 10 m2-class pointed instrument with 20 times the collecting area of the best past timing missions (such as RXTE) over the 2-30 keV range, which holds the capability to revolutionize studies of X-ray variability down to the millisecond time scales. Its ground-breaking characteristic is a low mass per unit surface, enabling an effective area of ~10 m^2 (@10 keV) at a reasonable weight. The development of such large but light experiment, with low mass and power per unit area, is now made possible by the recent advancements in the field of large-area silicon detectors - able to time tag an X-ray photon with an accuracy <10 {\\mu}s and an...

  16. Approved for Public Release, Distribution Unlimited Flexible and large area electronics (macroelectronics) using

    E-Print Network [OSTI]

    Alam, Muhammad A.

    Approved for Public Release, Distribution Unlimited 1 Flexible and large area electronics high performance applications to include RF systems. Keywords--Flexible electronics, large area electronics, macroelectronics, thin film transistors I. INTRODUCTION Flexible and large area electronics using

  17. Method of manufacturing a large-area segmented photovoltaic module

    DOE Patents [OSTI]

    Lenox, Carl

    2013-11-05

    One embodiment of the invention relates to a segmented photovoltaic (PV) module which is manufactured from laminate segments. The segmented PV module includes rectangular-shaped laminate segments formed from rectangular-shaped PV laminates and further includes non-rectangular-shaped laminate segments formed from rectangular-shaped and approximately-triangular-shaped PV laminates. The laminate segments are mechanically joined and electrically interconnected to form the segmented module. Another embodiment relates to a method of manufacturing a large-area segmented photovoltaic module from laminate segments of various shapes. Other embodiments relate to processes for providing a photovoltaic array for installation at a site. Other embodiments and features are also disclosed.

  18. Large area photodetector based on microwave cavity perturbation techniques

    SciTech Connect (OSTI)

    Braggio, C., E-mail: caterina.braggio@unipd.it; Carugno, G.; Sirugudu, R. K. [Dip. di Fisica e Astronomia and INFN Sez. di Padova, Via F. Marzolo 8, I-35131 Padova (Italy); Lombardi, A.; Ruoso, G. [INFN, Laboratori Nazionali di Legnaro, Viale dell'Università 2, I-35020 Legnaro (Italy)

    2014-07-28

    We present a preliminary study to develop a large area photodetector, based on a semiconductor crystal placed inside a superconducting resonant cavity. Laser pulses are detected through a variation of the cavity impedance, as a consequence of the conductivity change in the semiconductor. A novel method, whereby the designed photodetector is simulated by finite element analysis, makes it possible to perform pulse-height spectroscopy on the reflected microwave signals. We measure an energy sensitivity of 100 fJ in the average mode without the employment of low noise electronics and suggest possible ways to further reduce the single-shot detection threshold, based on the results of the described method.

  19. Enabling a High Throughput Real Time Data Pipeline for a Large Radio Telescope Array with GPUs

    E-Print Network [OSTI]

    Edgar, R G; Dale, K; Mitchell, D A; Ord, S M; Wayth, R B; Pfister, H; Greenhill, L J

    2010-01-01

    The Murchison Widefield Array (MWA) is a next-generation radio telescope currently under construction in the remote Western Australia Outback. Raw data will be generated continuously at 5GiB/sec. This high throughput motivates the development of on-site, real time processing and reduction in preference to archiving, transport and off-line processing. Maintaining real time operation will require a sustained performance of around 2.5TFLOP/sec (including convolutions, FFTs, interpolations and matrix multiplications). We describe a scalable heterogeneous computing pipeline implementation, exploiting both the high computing density and FLOP-per-Watt ratio of modern GPUs. The architecture is highly parallel within and across nodes, with all major processing elements performed by GPUs. Necessary scatter-gather operations along the pipeline are loosely synchronized and implemented in MPI. The MWA will be a frontier scientific instrument and a pathfinder for planned peta- and exascale facilities.

  20. Fabrication of large area Si cylindric drift detectors

    SciTech Connect (OSTI)

    Chen, W.; Kraner, H.W.; Li, Z.; Rehak, P. [Brookhaven National Lab., Upton, NY (United States); Hess, F. [Heidelberg Univ. (Germany). Dept. of Physics

    1993-04-01

    Advanced Si drift detector, a large area cylindrical drift detector (CDD), processing steps, with the exception of the ion implantation, were carried out in the BNL class 100 cleanroom. The double-side planer process technique was developed for the fabrication of CDD. Important improvements of the double-side planer process in this fabrication are the introduction of Al implantation protection mask and the remaining of a 1000 Angstroms oxide layer in the p-window during the implantation. Another important design of the CDD is the structure called ``river,`` which ,allows the current generated on Si-SiO{sub 2} interface to ``flow`` into the guard anode, and thus can minimize the leakage current at the signed anode. The test result showed that most of the signal anodes have the leakage current about 0.3 nA/cm{sup 2} for the best detector.

  1. Noise-Immune Conjugate Large-Area Atom Interferometers

    SciTech Connect (OSTI)

    Chiow Shengwey; Herrmann, Sven [Physics Department, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305 (United States); Chu, Steven; Mueller, Holger [Physics Department, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305 (United States); Department of Physics, University of California, 366 Le Conte Hall, Berkeley, California 94720-7300 (United States); Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California 94720 (United States)

    2009-07-31

    We present a pair of simultaneous conjugate Ramsey-Borde atom interferometers using large (20(Planck constant/2pi)k)-momentum transfer beam splitters, where (Planck constant/2pi)k is the photon momentum. Simultaneous operation allows for common-mode rejection of vibrational noise. This allows us to surpass the enclosed space-time area of previous interferometers with a splitting of 20(Planck constant/2pi)k by a factor of 2500. Using a splitting of 10(Planck constant/2pi)k, we demonstrate a 3.4 ppb resolution in the measurement of the fine structure constant. Examples for applications in tests of fundamental laws of physics are given.

  2. Plasma generating apparatus for large area plasma processing

    DOE Patents [OSTI]

    Tsai, C.C.; Gorbatkin, S.M.; Berry, L.A.

    1991-07-16

    A plasma generating apparatus for plasma processing applications is based on a permanent magnet line-cusp plasma confinement chamber coupled to a compact single-coil microwave waveguide launcher. The device creates an electron cyclotron resonance (ECR) plasma in the launcher and a second ECR plasma is created in the line cusps due to a 0.0875 tesla magnetic field in that region. Additional special magnetic field configuring reduces the magnetic field at the substrate to below 0.001 tesla. The resulting plasma source is capable of producing large-area (20-cm diam), highly uniform (.+-.5%) ion beams with current densities above 5 mA/cm[sup 2]. The source has been used to etch photoresist on 5-inch diam silicon wafers with good uniformity. 3 figures.

  3. Plasma generating apparatus for large area plasma processing

    DOE Patents [OSTI]

    Tsai, Chin-Chi (Oak Ridge, TN); Gorbatkin, Steven M. (Oak Ridge, TN); Berry, Lee A. (Oak Ridge, TN)

    1991-01-01

    A plasma generating apparatus for plasma processing applications is based on a permanent magnet line-cusp plasma confinement chamber coupled to a compact single-coil microwave waveguide launcher. The device creates an electron cyclotron resonance (ECR) plasma in the launcher and a second ECR plasma is created in the line cusps due to a 0.0875 tesla magnetic field in that region. Additional special magnetic field configuring reduces the magnetic field at the substrate to below 0.001 tesla. The resulting plasma source is capable of producing large-area (20-cm diam), highly uniform (.+-.5%) ion beams with current densities above 5 mA/cm.sup.2. The source has been used to etch photoresist on 5-inch diam silicon wafers with good uniformity.

  4. Fermi Large Area Telescope Constraints on the Gamma-ray Opacity...

    Office of Scientific and Technical Information (OSTI)

    Dept. IASF, Milan Padua U. AIM, Saclay ASDC, Frascati INFN, Perugia Perugia U. NASA, Goddard NASA, Goddard CRESST, Greenbelt CSST, Baltimore SLAC KIPAC, Menlo Park...

  5. Fermi Large Area Telescope Constraints on the Gamma-ray Opacity of the

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing(Journal Article) |production at aSciTech Connect Fe

  6. Fermi Large Area Telescope Observations of the Supernova Remnant G8.7-0.1

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing(Journal Article) |production at aSciTech Connect Fe(Journal Article) | SciTech

  7. Fermi Large Area Telescope Observations of the Supernova Remnant G8.7-0.1

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing(Journal Article) |production at aSciTech Connect Fe(Journal Article) |

  8. Observation of Supernova Remnant IC443 with the Fermi Large Area Telescope

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech ConnectSpeeding access to science information from DOE

  9. Observation of Supernova Remnant IC443 with the Fermi Large Area Telescope

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech ConnectSpeeding access to science information from DOE(Journal Article) | SciTech

  10. Pulsed Gamma-Rays From PSR J2021 3651 with the Fermi Large Area Telescope

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech ConnectSpeedingConnect Pulse energy measurement at the SXR instrument

  11. Pulsed Gamma-Rays From PSR J2021 3651 with the Fermi Large Area Telescope

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech ConnectSpeedingConnect Pulse energy measurement at the SXR instrument(Journal

  12. LUPUS I observations from the 2010 flight of the Balloon-borne large aperture submillimeter telescope for polarimetry

    SciTech Connect (OSTI)

    Matthews, Tristan G.; Chapman, Nicholas L.; Novak, Giles [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States); Ade, Peter A. R.; Hargrave, Peter C.; Nutter, David [Cardiff University, School of Physics and Astronomy, Queens Buildings, The Parade, Cardiff, CF24 3AA (United Kingdom); Angilè, Francesco E.; Devlin, Mark J.; Klein, Jeffrey [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States); Benton, Steven J.; Fissel, Laura M.; Gandilo, Natalie N.; Netterfield, Calvin B. [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street Toronto, ON M5S 3H4 (Canada); Chapin, Edward L. [XMM SOC, ESAC, Apartado 78, E-28691 Villanueva de la Cañada, Madrid (Spain); Fukui, Yasuo [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan); Gundersen, Joshua O. [Department of Physics, University of Miami, 1320 Campo Sano Drive, Coral Gables, FL 33146 (United States); Korotkov, Andrei L. [Department of Physics, Brown University, 182 Hope Street, Providence, RI 02912 (United States); Moncelsi, Lorenzo; Mroczkowski, Tony K. [California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Olmi, Luca [University of Puerto Rico, Rio Piedras Campus, Physics Department, Box 23343, UPR station, San Juan (Puerto Rico); and others

    2014-04-01

    The Balloon-borne Large Aperture Submillimeter Telescope for Polarimetry (BLASTPol) was created by adding polarimetric capability to the BLAST experiment that was flown in 2003, 2005, and 2006. BLASTPol inherited BLAST's 1.8 m primary and its Herschel/SPIRE heritage focal plane that allows simultaneous observation at 250, 350, and 500 ?m. We flew BLASTPol in 2010 and again in 2012. Both were long duration Antarctic flights. Here we present polarimetry of the nearby filamentary dark cloud Lupus I obtained during the 2010 flight. Despite limitations imposed by the effects of a damaged optical component, we were able to clearly detect submillimeter polarization on degree scales. We compare the resulting BLASTPol magnetic field map with a similar map made via optical polarimetry. (The optical data were published in 1998 by J. Rizzo and collaborators.) The two maps partially overlap and are reasonably consistent with one another. We compare these magnetic field maps to the orientations of filaments in Lupus I, and we find that the dominant filament in the cloud is approximately perpendicular to the large-scale field, while secondary filaments appear to run parallel to the magnetic fields in their vicinities. This is similar to what is observed in Serpens South via near-IR polarimetry, and consistent with what is seen in MHD simulations by F. Nakamura and Z. Li.

  13. Final Scientific/Technical Report Development of Large-Area Photo...

    Office of Scientific and Technical Information (OSTI)

    Final ScientificTechnical Report Development of Large-Area Photo-Detectors Citation Details In-Document Search Title: Final ScientificTechnical Report Development of Large-Area...

  14. Finding Large Aperture Fractures in Geothermal Resource Areas...

    Open Energy Info (EERE)

    Fractures in Geothermal Resource Areas Using a Three-Component Long-Offset Surface Seismic Survey Geothermal Project Jump to: navigation, search Last modified on July 22, 2011....

  15. Finding Large Aperture Fractures in Geothermal Resource Areas...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Seismic Survey DOE Geothermal Peer Review 2010 - Presentation. Project summary: Drilling into large aperture open fractures (LAFs) typically yield production wells with...

  16. Final Scientific/Technical Report Development of Large-Area Photo...

    Office of Scientific and Technical Information (OSTI)

    very large-area planar photodetectors. The proposed detectors have integrated transmission-line readout and sampling electronics able to achieve timing and position...

  17. Role of Large Balancing Areas In Integrating Solar Generation: Solar Integration Series. 3 of 3 (Brochure)

    SciTech Connect (OSTI)

    Not Available

    2011-05-01

    The third out of a series of three fact sheets describing the role of large balancing areas in integrating solar generation.

  18. Spherical Torus Plasma Interactions with Large-Area Liquid Lithium Surfaces in CDX-U

    E-Print Network [OSTI]

    California at Los Angeles, University of

    Outside of Plasma" (DOLLOP) lithium wall conditioning experiments,[3] for example, in the Tokamak Fusion, introduction of large area lithium limiter targets and walls into existing tokamak facilities has not yet taken- 1 - Spherical Torus Plasma Interactions with Large-Area Liquid Lithium Surfaces in CDX-U R. KAITA

  19. Large-Area Free-Standing Ultrathin Single-Crystal Silicon as Processable Materials

    E-Print Network [OSTI]

    Cui, Yi

    Large-Area Free-Standing Ultrathin Single-Crystal Silicon as Processable Materials Shuang Wang in electronics, biotechnology, and energy applications. Here we demonstrate large-area free- standing ultrathin of surface together with the interesting property of these free-standing ultrathin Si materials opens up

  20. Large area substrate for surface enhanced Raman spectroscopy (SERS) using glass-drawing technique

    DOE Patents [OSTI]

    Ivanov, Ilia N.; Simpson, John T.

    2012-06-26

    A method of making a large area substrate comprises drawing a plurality of tubes to form a plurality of drawn tubes, and cutting the plurality of drawn tubes into cut drawn tubes. Each cut drawn tube has a first end and a second end along the longitudinal direction of the respective cut drawn tube. The cut drawn tubes collectively have a predetermined periodicity. The method of making a large area substrate also comprises forming a metal layer on the first ends of the cut drawn tubes to provide a large area substrate.

  1. Power Challenges of Large Scale Research Infrastructures: the Square Kilometer Array and Solar Energy Integration; Towards a zero-carbon footprint next generation telescope

    E-Print Network [OSTI]

    Barbosa, Domingos; Ruiz, Valeriano; Silva, Manuel; Verdes-Montenegro, Lourdes; Santander-Vela, Juande; Maia, Dalmiro; Antón, Sonia; van Ardenne, Arnold; Vetter, Matthias; Kramer, Michael; Keller, Reinhard; Pereira, Nuno; Silva, Vitor

    2012-01-01

    The Square Kilometer Array (SKA) will be the largest Global science project of the next two decades. It will encompass a sensor network dedicated to radioastronomy, covering two continents. It will be constructed in remote areas of South Africa and Australia, spreading over 3000Km, in high solar irradiance latitudes. Solar Power supply is therefore an option to power supply the SKA and contribute to a zero carbon footprint next generation telescope. Here we outline the major characteristics of the SKA and some innovation approaches on thermal solar energy Integration with SKA prototypes.

  2. Large area high density quantized magnetic disks fabricated using nanoimprint lithography

    E-Print Network [OSTI]

    for fabricating large area quantized magnetic disks QMDs using nanoimprint lithography NIL , electroplating or a via array. The other is that for high resolution an antireflection coating ARC layer is needed, which

  3. Broadband optical properties of large-area monolayer CVD molybdenum disulfide

    E-Print Network [OSTI]

    Li, Wei

    Recently emerging large-area single-layer MoS[subscript 2] grown by chemical vapor deposition has triggered great interest due to its exciting potential for applications in advanced electronic and optoelectronic devices. ...

  4. Optical nano-woodpiles: large-area metallic photonic crystals and metamaterials

    E-Print Network [OSTI]

    Ibbotson, Lindsey A.; Demetriadou, Angela; Stephen, Croxall; Hess, Ortwin; Baumberg, Jeremy J.

    2015-02-09

    Metallic woodpile photonic crystals and metamaterials operating across the visible spectrum are extremely difficult to construct over large areas, because of the intricate three-dimensional nanostructures and sub-50?nm features demanded. Previous...

  5. Iron (III) Chloride doping of large-area chemical vapor deposition graphene

    E-Print Network [OSTI]

    Song, Yi, S.M. Massachusetts Institute of Technology

    2013-01-01

    Chemical doping is an effective method of reducing the sheet resistance of graphene. This thesis aims to develop an effective method of doping large area Chemical Vapor Deposition (CVD) graphene using Iron (III) Chloride ...

  6. Low temperature lithographically patterned metal oxide transistors for large area electronics

    E-Print Network [OSTI]

    Wang, Annie I. (Annie I-Jen), 1981-

    2011-01-01

    Optically transparent, wide bandgap metal oxide semiconductors are a promising candidate for large-area electronics technologies that require lightweight, temperature-sensitive flexible substrates. Because these thin films ...

  7. innovate educate improve lives Large areas of land along the Gulf

    E-Print Network [OSTI]

    be installed with lighter equipment which has less environmental impact. Wood offers excellent work- abilityinnovate educate improve lives Large areas of land along the Gulf of Mexico have been flooded the impact of a wide array of insects, wood decay and rot. The most serious pest in this area is the Formosan

  8. Synthesis, Characterization, and Properties of Large-Area Graphene Films Xuesong Lia

    E-Print Network [OSTI]

    of exfoliated graphite oxide may be a candidate for large-scale preparation of graphene.(17-22) HoweverSynthesis, Characterization, and Properties of Large-Area Graphene Films Xuesong Lia , Weiwei Caia of Texas at Austin, Austin, TX 78712 b Texas Instruments Incorporated, Dallas, TX 75243 Graphene and few

  9. Large bearings with incorporated gears, high stiffness and precision for the Swedish Solar Telescope (SST) on La Palma

    E-Print Network [OSTI]

    Rutten, Rob

    1 Large bearings with incorporated gears, high stiffness and precision for the Swedish Solar the meshing teeth of the large gear wheel and the pinion. High preload forces to achieve line contact of the combination of bearing and gear teeth. An additional problem was the relatively thin section of the bearings

  10. High resolution telescope

    DOE Patents [OSTI]

    Massie, Norbert A. (San Ramon, CA); Oster, Yale (Danville, CA)

    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.

  11. Beam Test of a Large Area nonn Silicon Strip Detector with Fast Binary Readout Electronics

    E-Print Network [OSTI]

    Beam Test of a Large Area n­on­n Silicon Strip Detector with Fast Binary Readout Electronics Y test was carried out for the non­irradiated and the irradiated detector modules. Efficiency, noise occupancy and performance in the edge regions were analyzed using the beam test data. High efficiency

  12. Transfer-Free Batch Fabrication of Large-Area Suspended Graphene Membranes

    E-Print Network [OSTI]

    Zettl, Alex

    heightened for the preparation of sus- pended graphene structures to ascertain graphene's fundamentalTransfer-Free Batch Fabrication of Large- Area Suspended Graphene Membranes Benjami´n Alema of the predicted properties arising from the two-dimensional nature of graphene1 4 can be obscured or altered

  13. Beam Test of a Large Area nonn Silicon Strip Detector with Fast Binary Readout Electronics

    E-Print Network [OSTI]

    Beam Test of a Large Area n­on­n Silicon Strip Detector with Fast Binary Readout Electronics Y modules was irradiated with protons to a fluence of 1.2 × 10 14 p/cm 2 . A beam test was carried out in the edge regions were analyzed using the beam test data. High efficiency both for the non

  14. Transformational, Large Area Fabrication of Nanostructured Materials Using Plasma Arc Lamps

    SciTech Connect (OSTI)

    2009-03-01

    This factsheet describes a study that will address critical additional steps over large areas of as-synthesized nanostructured materials, such as annealing, phase transformation, or activation of dopants, dramatically reducing the processing costs of the solid-state lighting and photovoltaic materials.

  15. Large Area Imaging Detector for Neutron Scattering Based on Boron-Rich Liquid Scintillator

    E-Print Network [OSTI]

    Large Area Imaging Detector for Neutron Scattering Based on Boron-Rich Liquid Scintillator D detector, neutron scattering, gaseous photomultiplier Pacs: 29.40.Mc, 29.40.Cs, 61.12.-q, 61.12.Ex to Nucl. Instr. & Meth. A WIS/31/02-July-DPP #12;1. Introduction Slow neutron scattering is one of the key

  16. Enabling single-mode behavior over large areas with photonic Dirac cones

    E-Print Network [OSTI]

    processing devices and energy harvesting systems. Since its isolation from bulk graphite in 2004 (1, 2012) Many of graphene's unique electronic properties emerge from its Dirac-like electronic energy enhancement of the spontaneous emission coupling efficiency (the -factor) over large areas, defying the common

  17. Continuous near-field electrospinning for large area deposition of orderly nanofiber patterns

    E-Print Network [OSTI]

    Lin, Liwei

    Continuous near-field electrospinning for large area deposition of orderly nanofiber patterns Chieh; accepted 4 August 2008; published online 24 September 2008 A continuous near-field electrospinning NFES the onset of electrospinning, a bias voltage is applied to a semispherical shaped polymer droplet outside

  18. Simulation of Large-Area Silicon Solar Cells1 Gernot Heiser2

    E-Print Network [OSTI]

    New South Wales, University of

    Simulation of Large-Area Silicon Solar Cells1 Gernot Heiser2 Pietro P. Altermatt3 The University of high-efficiency silicon solar cells. In the past, however, such modelling could only be applied to produce an accurate model of a full-sized high-efficiency solar cell. We demon- strate the power

  19. DOI: 10.1002/anie.201105439 Fabrication of Large-Area Two-Dimensional Colloidal Crystals**

    E-Print Network [OSTI]

    Asher, Sanford A.

    Polymers DOI: 10.1002/anie.201105439 Fabrication of Large-Area Two-Dimensional Colloidal Crystals-dimensional crystalline colloidal arrays (CCAs) have numerous applications, such as photonic crystal materials and sensors to prepare close-packed 2D colloidal crystals by floating and re-deposit- ing colloidal monolayers at the air

  20. A novel lithography technique for formation of large areas of uniform nanostructures

    E-Print Network [OSTI]

    Shahriar, Selim

    such as plasmonics, sensors, storage devices, solar cells, nano-filtration and artificial kidneys require applications such as surface plasmonics[1] , data storage[2] , optoelectronic devices[3] , and nanoA novel lithography technique for formation of large areas of uniform nanostructures Wei Wu

  1. LAYER TRANSFER OF LARGE AREA MACROPOROUS SILICON FOR MONOCRYSTALLINE THIN-FILM SOLAR CELLS

    E-Print Network [OSTI]

    LAYER TRANSFER OF LARGE AREA MACROPOROUS SILICON FOR MONOCRYSTALLINE THIN-FILM SOLAR CELLS Marco-based solar cells is approximately 200 µm with a kerf loss of about 100 µm caused by wire sawing. However, lower wafer thicknesses are sufficient for achieving high solar cell efficiencies exceeding 20 % [1

  2. ATLAS: Australia Telescope Large Area Survey: Deep Radio Observations of the CDFS-SWIRE and ELAIS-S1 fields

    E-Print Network [OSTI]

    Norris, Ray

    . · Radio observations give information which is not available at any other wavelength. For example, we have~10 µJy. · We identify a class of radio sources (IFRS=Infrared-faint radio sources) with no visible Center, California Institute of Technology, USA 3: University of California at San Diego, USA. 4: Anglo

  3. Fermi Large Area Telescope observations of high-energy gamma-ray emission from behind-the-limb solar flares

    E-Print Network [OSTI]

    Pesce-Rollins, Melissa; Petrosian, Vahe'; Liu, Wei; da Costa, Fatima Rubio; Allafort, Alice

    2015-01-01

    Fermi-LAT >30 MeV observations have increased the number of detected solar flares by almost a factor of 10 with respect to previous space observations. These sample both the impulsive and long duration phases of GOES M and X class flares. Of particular interest is the recent detections of three solar flares whose position behind the limb was confirmed by the STEREO-B spacecraft. While gamma-ray emission up to tens of MeV resulting from proton interactions has been detected before from occulted solar flares, the significance of these particular events lies in the fact that these are the first detections of >100 MeV gamma-ray emission from footpoint-occulted flares. We will present the Fermi-LAT, RHESSI and STEREO observations of these flares and discuss the various emission scenarios for these sources and implications for the particle acceleration mechanisms.

  4. Large Area Microcorrals and Cavity Formation on Cantilevers using a Focused Ion Beam

    SciTech Connect (OSTI)

    Saraf, Laxmikant V.; Britt, David W.

    2011-09-14

    We utilize focused ion beam (FIB) to explore various sputtering parameters to form large area microcorrals and cavities on cantilevers. Microcorrals were rapidly created by modifying ion beam blur and overlaps. Modification in FIB sputtering parameters affects the periodicity and shape of corral microstructure. Cantilever deflections show ion beam amorphization effects as a function of sputtered area and cantilever base cavities with or without side walls. The FIB sputtering parameters address a method for rapid creation of a cantilever tensiometer with integrated fluid storage and delivery.

  5. A COMBINED VERY LARGE TELESCOPE AND GEMINI STUDY OF THE ATMOSPHERE OF THE DIRECTLY IMAGED PLANET, ? PICTORIS b

    SciTech Connect (OSTI)

    Currie, Thayne; Jayawardhana, Ray; Burrows, Adam; Madhusudhan, Nikku; Fukagawa, Misato; Girard, Julien H.; Dawson, Rebekah; Murray-Clay, Ruth; Kenyon, Scott; Kuchner, Marc; Matsumura, Soko; Chambers, John; Bromley, Ben

    2013-10-10

    We analyze new/archival VLT/NaCo and Gemini/NICI high-contrast imaging of the young, self-luminous planet ? Pictoris b in seven near-to-mid IR photometric filters, using advanced image processing methods to achieve high signal-to-noise, high precision measurements. While ? Pic b's near-IR colors mimic those of a standard, cloudy early-to-mid L dwarf, it is overluminous in the mid-infrared compared to the field L/T dwarf sequence. Few substellar/planet-mass objects—i.e., ? And b and 1RXJ 1609B—match ? Pic b's JHK{sub s}L' photometry and its 3.1 ?m and 5 ?m photometry are particularly difficult to reproduce. Atmosphere models adopting cloud prescriptions and large (?60 ?m) dust grains fail to reproduce the ? Pic b spectrum. However, models incorporating thick clouds similar to those found for HR 8799 bcde, but also with small (a few microns) modal particle sizes, yield fits consistent with the data within the uncertainties. Assuming solar abundance models, thick clouds, and small dust particles ((a) = 4 ?m), we derive atmosphere parameters of log (g) = 3.8 ± 0.2 and T{sub eff} = 1575-1650 K, an inferred mass of 7{sup +4}{sub -3} M{sub J} , and a luminosity of log(L/L{sub ?}) ?–3.80 ± 0.02. The best-estimated planet radius, ?1.65 ± 0.06 R{sub J} , is near the upper end of allowable planet radii for hot-start models given the host star's age and likely reflects challenges constructing accurate atmospheric models. Alternatively, these radii are comfortably consistent with hot-start model predictions if ? Pic b is younger than ?7 Myr, consistent with a late formation well after its host star's birth ?12{sup +8}{sub -4} Myr ago.

  6. Caustic Recycle from Hanford Tank Waste Using Large Area NaSICON Structures (LANS)

    SciTech Connect (OSTI)

    Fountain, Matthew S.; Sevigny, Gary J.; Balagopal, S.; Bhavaraju, S.

    2009-03-31

    This report presents the results of a 5-day test of an electrochemical bench-scale apparatus using a proprietary (NAS-GY) material formulation of a (Na) Super Ion Conductor (NaSICON) membrane in a Large Area NaSICON Structures (LANS) configuration. The primary objectives of this work were to assess system performance, membrane seal integrity, and material degradation while removing Na from Group 5 and 6 tank waste from the Hanford Site.

  7. Development of process to transfer large areas of LPCVD graphene from copper foil to a porous support substrate

    E-Print Network [OSTI]

    O'Hern, Sean C. (Sean Carson)

    2011-01-01

    In this thesis, I present a procedure by which to transfer greater than 25 mm² areas of high-quality graphene synthesized via low-pressure chemical vapor deposition from copper foil to porous support substrates. Large-area, ...

  8. The Role of Large Balancing Areas In Integrating Solar Generation: Solar Integration Series. 3 of 3 (Brochure)

    SciTech Connect (OSTI)

    Solar Energy Technologies Program

    2011-05-03

    The third out of a series of three fact sheets describing the role of large balancing areas in integrating solar generation.

  9. The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) 2005: A 4 sq. deg Galactic Plane Survey in Vulpecula (l=59)

    E-Print Network [OSTI]

    E. L. Chapin; P. A. R. Ade; J. J. Bock; C. Brunt; M. J. Devlin; S. Dicker; M. Griffin; J. O. Gundersen; M. Halpern; P. C. Hargrave; D. H. Hughes; J. Klein; G. Marsden; P. G. Martin; P. Mauskopf; C. B. Netterfield; L. Olmi; E. Pascale; G. Patanchon; M. Rex; D. Scott; C. Semisch; M. D. P. Truch; C. Tucker; G. S. Tucker; M. P. Viero; D. V. Wiebe

    2007-11-21

    We present the first results from a new 250, 350, and 500 micron Galactic Plane survey taken with the Balloon-borne Large-Aperture Submillimeter Telescope (BLAST) in 2005. This survey's primary goal is to identify and characterize high-mass proto-stellar objects (HMPOs). The region studied here covers 4 sq. deg near the open cluster NGC 6823 in the constellation Vulpecula (l=59). We find 60 compact sources (0) velocities combined with a variety of other velocity and morphological data in the literature. In total, 49 sources are associated with a molecular cloud complex encompassing NGC 6823 (distance ~2.3kpc), 10 objects with the Perseus Arm (~8.5kpc) and one object is probably in the outer Galaxy (~14kpc). Near NGC 6823, the inferred luminosities and masses of BLAST sources span ~40-10^4 L_\\odot, and ~15-700 M_\\odot, respectively. The mass spectrum is compatible with molecular gas masses in other high-mass star forming regions. Several luminous sources appear to be Ultra Compact HII regions powered by early B stars. However, many of the objects are cool, massive gravitationally-bound clumps with no obvious internal radiation from a protostar, and hence excellent HMPO candidates.

  10. Large-Area (over 50 cm 50 cm) Freestanding Films of Colloidal InP/ ZnS Quantum Dots

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    Large-Area (over 50 cm × 50 cm) Freestanding Films of Colloidal InP/ ZnS Quantum Dots Evren of flexible, freestanding films of InP/ZnS quantum dots (QDs) using fatty acid ligands across very large areas avoiding the need for ligand exchange. When pumped by a blue LED, these Cd-free QD films allow for high

  11. Microwave Absorption and Radiation from Large-area Multilayer CVD Graphene

    E-Print Network [OSTI]

    Wu, Bian; Tuncer, Hatice M.; Katsounaros, Anestis; Wu, Weiping; Cole, Matthew T.; Ying, Kai; Zhang, Lianhong; Milne, William I.; Hao, Yang

    the emergence of reproducible large-area synthesis of graphene by chemical coplanar waveguides [21–23], rectangular waveguides [24], ve been carried out in the microwave transisto t and dyn osed [36]. multilayer graphene is also of great interest as a h... metamaterial in the THz regime [37]. Microwave absorption of graphene composites have been experimentally studied to design microwave absorbing mate- * Corresponding author. C A R B O N 7 7 ( 2 0 1 4 ) 8 1 4 –8 2 2 Avai lab le at www.sc iencedi rect .com...

  12. Approaching total absorption at near infrared in a large area monolayer graphene by critical coupling

    SciTech Connect (OSTI)

    Liu, Yonghao; Chadha, Arvinder; Zhao, Deyin; Shuai, Yichen; Menon, Laxmy; Yang, Hongjun; Zhou, Weidong; Piper, Jessica R.; Fan, Shanhui; Jia, Yichen; Xia, Fengnian; Ma, Zhenqiang

    2014-11-03

    We demonstrate experimentally close to total absorption in monolayer graphene based on critical coupling with guided resonances in transfer printed photonic crystal Fano resonance filters at near infrared. Measured peak absorptions of 35% and 85% were obtained from cavity coupled monolayer graphene for the structures without and with back reflectors, respectively. These measured values agree very well with the theoretical values predicted with the coupled mode theory based critical coupling design. Such strong light-matter interactions can lead to extremely compact and high performance photonic devices based on large area monolayer graphene and other two–dimensional materials.

  13. Tuning the thickness of electrochemically grafted layers in large area molecular junctions

    SciTech Connect (OSTI)

    Fluteau, T.; Bessis, C.; Barraud, C. Della Rocca, M. L.; Lafarge, P.; Martin, P.; Lacroix, J.-C.

    2014-09-21

    We have investigated the thickness, the surface roughness, and the transport properties of oligo(1-(2-bisthienyl)benzene) (BTB) thin films grafted on evaporated Au electrodes, thanks to a diazonium-based electro-reduction process. The thickness of the organic film is tuned by varying the number of electrochemical cycles during the growth process. Atomic force microscopy measurements reveal the evolution of the thickness in the range of 2–27 nm. Its variation displays a linear dependence with the number of cycles followed by a saturation attributed to the insulating behavior of the organic films. Both ultrathin (2 nm) and thin (12 and 27 nm) large area BTB-based junctions have then been fabricated using standard CMOS processes and finally electrically characterized. The electronic responses are fully consistent with a tunneling barrier in case of ultrathin BTB film whereas a pronounced rectifying behavior is reported for thicker molecular films.

  14. A large area plastic scintillator detector array for fast neutron measurements

    E-Print Network [OSTI]

    P. C. Rout; D. R. Chakrabarty; V. M. Datar; Suresh Kumar; E. T. Mirgule; A. Mitra; V. Nanal; R. Kujur

    2008-09-04

    A large area plastic scintillator detector array(~ 1 m x1m) has been set up for fast neutron spectroscopy at the BARC-TIFR Pelletron laboratory, Mumbai. The energy, time and position response has been measured for electrons using radioactive sources and for mono-energetic neutrons using the 7Li(p,n1)7Be*(0.429 MeV) reaction at proton energies between 6.3 and 19 MeV. A Monte Carlo simulation of the energy dependent efficiency of the array for neutron detection is in agreement with the 7Li(p,n1) measurements. The array has been used to measure the neutron spectrum, in the energy range of 4-12 MeV, in the reaction 12C+ 93Nb at E(12C)= 40 MeV. This is in reasonable agreement with a statistical model calculation.

  15. Large area directly heated lanthanum hexaboride cathode structure having predetermined emission profile

    DOE Patents [OSTI]

    Leung, Ka-Ngo; Gordon, K.C.; Kippenhan, D.O.; Purgalis, P.; Moussa, D.; Williams, M.D.; Wilde, S.B.; West, M.W.

    1987-10-16

    A large area directly heated lanthanum hexaboride (LaB/sub 6/) cathode system is disclosed. The system comprises a LaB/sub 6/ cathode element generally circular in shape about a central axis. The cathode element has a head with an upper substantially planar emission surface, and a lower downwardly and an intermediate body portion which diminishes in cross-section from the head towards the base of the cathode element. A central rod is connected to the base of the cathode element and extends along the central axis. Plural upstanding spring fingers are urged against an outer peripheral contact surface of the head end to provide a mechanical and electrical connection to the cathode element. 7 figs

  16. Development of large area transparent conducting oxides from a combinatorial lead for organic solid state lighting

    SciTech Connect (OSTI)

    Matson, Dean W.; Bonham, Charles C.; Swensen, James S.; Wang, Liang; Padmaperuma, Asanga B.; Gaspar, Daniel J.; Berry, J. J.; Sigdel, Ajaya K.; Gorrie, Christopher W.; Ginley, D. S.

    2009-09-01

    Organic light emitting device (OLEDs) may provide a low-cost, long-lived, and efficient wide area lighting solution if a number of challenges in reliability, cost and efficiency can be overcome. There is a need to develop new TCOs for use as the anode in a bottom-emitting device that do not contain In, have optimal work function, conductivity and visible light transmission properties, possess acceptable stability and possess a high work function to match the deep HOMO of blue OLED HTLs. We report here results from our efforts to scale up sputter deposition on large area substrates (up to 12”x12”) of TCO candidates (including Ga:ZnO and Zn:SnO) identified using combinatorial methods. We present transmission, electrical properties, work function, compositional and structural data for these films. Finally, we have evaluated the use of these materials in OLEDs, and show device performance comparisons between devices fabricated on combinatorial substrates, single composition substrates, and substrates grown at larger scale (up to 12”x12”). Post-operation analysis of the materials using a combination of surface analysis and electron microscopy techniques was performed. The device results demonstrate that we are able to generate substrates with the appropriate work function to reduce the operating voltage of blue phosphorescent OLEDs compared to commercial ITO, which we ascribe to improved work function-HOMO energy matching leading to more efficient charge injection into the device HTL.

  17. CARMA LARGE AREA STAR FORMATION SURVEY: OBSERVATIONAL ANALYSIS OF FILAMENTS IN THE SERPENS SOUTH MOLECULAR CLOUD

    SciTech Connect (OSTI)

    Fernández-López, M.; Looney, L.; Lee, K.; Segura-Cox, D.; Arce, H. G.; Plunkett, A.; Mundy, L. G.; Storm, S.; Teuben, P. J.; Pound, M.; Isella, A.; Kauffmann, J.; Tobin, J. J.; Rosolowsky, E.; Kwon, W.; Ostriker, E.; Tassis, K.; Shirley, Y. L.

    2014-08-01

    We present the N{sub 2}H{sup +} (J = 1 ? 0) map of the Serpens South molecular cloud obtained as part of the CARMA Large Area Star Formation Survey. The observations cover 250 arcmin{sup 2} and fully sample structures from 3000 AU to 3 pc with a velocity resolution of 0.16 km s{sup –1}, and they can be used to constrain the origin and evolution of molecular cloud filaments. The spatial distribution of the N{sub 2}H{sup +} emission is characterized by long filaments that resemble those observed in the dust continuum emission by Herschel. However, the gas filaments are typically narrower such that, in some cases, two or three quasi-parallel N{sub 2}H{sup +} filaments comprise a single observed dust continuum filament. The difference between the dust and gas filament widths casts doubt on Herschel ability to resolve the Serpens South filaments. Some molecular filaments show velocity gradients along their major axis, and two are characterized by a steep velocity gradient in the direction perpendicular to the filament axis. The observed velocity gradient along one of these filaments was previously postulated as evidence for mass infall toward the central cluster, but these kind of gradients can be interpreted as projection of large-scale turbulence.

  18. IEEE JOURNAL OF OCEANIC ENGINEERING, VOL. 28, NO. 4, OCTOBER 2003 651 Toward Large-Area Mosaicing for

    E-Print Network [OSTI]

    Singh, Hanumant

    IEEE JOURNAL OF OCEANIC ENGINEERING, VOL. 28, NO. 4, OCTOBER 2003 651 Toward Large-Area Mosaicing for Underwater Scientific Applications Oscar Pizarro, Student Member, IEEE, and Hanumant Singh Abstract

  19. A SPITZER SPACE TELESCOPE FAR-INFRARED SPECTRAL ATLAS OF COMPACT SOURCES IN THE MAGELLANIC CLOUDS. I. THE LARGE MAGELLANIC CLOUD

    SciTech Connect (OSTI)

    Van Loon, Jacco Th.; Oliveira, Joana M. [Astrophysics Group, Lennard-Jones Laboratories, Keele University, Staffordshire ST5 5BG (United Kingdom); Gordon, Karl D.; Meixner, Margaret; Shiao, Bernie; Boyer, Martha L. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Kemper, F.; Woods, Paul M. [Jodrell Bank Centre for Astrophysics, Alan Turing Building, School of Physics and Astronomy, The University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); Tielens, A. G. G. M. [Leiden Observatory, P.O. Box 9513, NL-2300 RA Leiden (Netherlands); Marengo, Massimo [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Indebetouw, Remy; Chen, C.-H. Rosie [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904 (United States); Sloan, G. C. [Department of Astronomy, Cornell University, Ithaca, NY 14853 (United States)], E-mail: jacco@astro.keele.ac.uk

    2010-01-15

    We present far-infrared spectra, {lambda} = 52-93 {mu}m, obtained with the Spitzer Space Telescope in the spectral energy distribution mode of its MIPS instrument, of a representative sample of the most luminous compact far-infrared sources in the Large Magellanic Cloud (LMC). These include carbon stars, OH/IR asymptotic giant branch (AGB) stars, post-AGB objects and planetary nebulae, the R CrB-type star HV 2671, the OH/IR red supergiants (RSGs) WOH G064 and IRAS 05280 - 6910, the three B[e] stars IRAS 04530 - 6916, R 66 and R 126, the Wolf-Rayet star Brey 3a, the luminous blue variable (LBV) R 71, the supernova remnant N 49, a large number of young stellar objects (YSOs), compact H II regions and molecular cores, and a background galaxy at a redshift z {approx_equal} 0.175. We use the spectra to constrain the presence and temperature of cold dust and the excitation conditions and shocks within the neutral and ionized gas, in the circumstellar environments and interfaces with the surrounding interstellar medium (ISM). First, we introduce a spectral classification scheme. Then, we measure line strengths, dust temperatures, and IR luminosities. Objects associated with star formation are readily distinguished from evolved stars by their cold dust and/or fine-structure lines. Evolved stars, including the LBV R 71, lack cold dust except in some cases where we argue that this is swept-up ISM. This leads to an estimate of the duration of the prolific dust-producing phase ('superwind') of several thousand years for both RSGs and massive AGB stars, with a similar fractional mass loss experienced despite the different masses. We tentatively detect line emission from neutral oxygen in the extreme RSG WOH G064, which suggests a large dust-free cavity with implications for wind driving. In N 49, the shock between the supernova ejecta and ISM is revealed in spectacular fashion by its strong [O I] {lambda}63 {mu}m emission and possibly water vapor; we estimate that 0.2 M {sub sun} of ISM dust was swept up. On the other hand, some of the compact H II regions display pronounced [O III] {lambda}88 {mu}m emission. The efficiency of photoelectric heating in the interfaces of ionized gas and molecular clouds is estimated at 0.1%-0.3%. We confirm earlier indications of a low nitrogen content in the LMC. Evidence for solid state emission features is found in both young and evolved objects, but the carriers of these features remain elusive; some of the YSOs are found to contain crystalline water ice. The spectra constitute a valuable resource for the planning and interpretation of observations with the Herschel Space Observatory and the Stratospheric Observatory For Infrared Astronomy.

  20. 19.4% -EFFICIENT LARGE AREA REAR-PASSIVATED SCREEN-PRINTED SILICON SOLAR CELLS T. Dullweber*1

    E-Print Network [OSTI]

    -printed cells by 0.2% [6,7]. The electrical and optical losses of the full- area Al-BSF at the rear side can19.4% -EFFICIENT LARGE AREA REAR-PASSIVATED SCREEN-PRINTED SILICON SOLAR CELLS T. Dullweber*1 , S implemented a baseline solar cell process based on today's standard industrially manufactured silicon solar

  1. A direct thin-film path towards low-cost large-area III-V photovoltaics

    E-Print Network [OSTI]

    California at Berkeley, University of

    A direct thin-film path towards low-cost large-area III-V photovoltaics Rehan Kapadia1,2 *, Zhibin-V photovoltaics (PVs) have demonstrated the highest power conversion efficiencies for both single- and multi times, and large equipment investments restrict applications to concentrated and space photovoltaics

  2. SPLASH: The Southern Parkes Large-Area Survey in Hydroxyl - First Science from the Pilot Region

    E-Print Network [OSTI]

    Dawson, J R; Jones, P A; Breen, S L; Cunningham, M R; Lowe, V; Jones, C; Purcell, C; Caswell, J L; Carretti, E; McClure-Griffiths, N M; Ellingsen, S P; Green, J A; Gómez, J F; Krishnan, V; Dickey, J M; Imai, H; Gibson, S J; Hennebelle, P; Lo, N; Hayakawa, T; Fukui, Y; Mizuno, A

    2013-01-01

    SPLASH (the Southern Parkes Large-Area Survey in Hydroxyl) is a sensitive, unbiased and fully-sampled survey of the Southern Galactic Plane and Galactic Centre in all four ground-state transitions of the hydroxyl (OH) radical. The survey provides a deep census of 1612-, 1665-, 1667- and 1720-MHz OH absorption and emission from the Galactic ISM, and is also an unbiased search for maser sources in these transitions. We present here first results from the SPLASH pilot region, which covers Galactic longitudes 334 to 344 degrees and latitudes of -2 to +2 degrees. Diffuse OH is widely detected in all four transitions, with optical depths that are always small (averaged over the Parkes beam), and with departures from LTE common even in the 1665- and 1667-MHz main lines. To a 3$\\sigma$ sensitivity of 30 mK, we find no evidence of OH envelopes extending beyond the CO-bright regions of molecular cloud complexes, and conclude that the similarity of the OH excitation temperature and the level of the continuum background ...

  3. Cooperative Island Growth of Large Area Single-Crystal Graphene by Chemical Vapor Deposition on Cu

    SciTech Connect (OSTI)

    Regmi, Murari [Oak Ridge National Laboratory (ORNL); Rouleau, Christopher [Oak Ridge National Laboratory (ORNL); Puretzky, Alexander A [ORNL; Ivanov, Ilia N [ORNL; Geohegan, David B [ORNL; Chen, Jihua [ORNL; Eastman, Jeffrey [Argonne National Laboratory (ANL); Eres, Gyula [ORNL

    2014-01-01

    We describe a two-step approach for suppressing nucleation of graphene on Cu using chemical vapor deposition. In the first step, as received Cu foils are oxidized in air at temperatures up to 500 C to remove surface impurities and to induce the regrowth of Cu grains during subsequent annealing in H2 flow at 1040 C prior to graphene growth. In the second step, transient reactant cooling is performed by using a brief Ar pulse at the onset of growth to induce collisional deactivation of the carbon growth species. The combination of these two steps results in a three orders of magnitude reduction in the graphene nucleation density, enabling the growth of millimeter-size single crystal graphene grains. A kinetic model shows that suppressing nucleation promotes a cooperative island growth mode that favors the formation of large area single crystal graphene, and it is accompanied by a roughly 3 orders of magnitude increase in the reactive sticking probability of methane compared to that in random nucleation growth.

  4. Novel Large Area High Resolution Neutron Detector for the Spallation Neutron Source

    SciTech Connect (OSTI)

    Lacy, Jeffrey L

    2009-05-22

    Neutron scattering is a powerful technique that is critically important for materials science and structural biology applications. The knowledge gained from past developments has resulted in far-reaching advances in engineering, pharmaceutical and biotechnology industries, to name a few. New facilities for neutron generation at much higher flux, such as the SNS at Oak Ridge, TN, will greatly enhance the capabilities of neutron scattering, with benefits that extend to many fields and include, for example, development of improved drug therapies and materials that are stronger, longer-lasting, and more impact-resistant. In order to fully realize this enhanced potential, however, higher neutron rates must be met with improved detection capabilities, particularly higher count rate capability in large size detectors, while maintaining practicality. We have developed a neutron detector with the technical and economic advantages to accomplish this goal. This new detector has a large sensitive area, offers 3D spatial resolution, high sensitivity and high count rate capability, and it is economical and practical to produce. The proposed detector technology is based on B-10 thin film conversion of neutrons in long straw-like gas detectors. A stack of many such detectors, each 1 meter in length, and 4 mm in diameter, has a stopping power that exceeds that of He-3 gas, contained at practical pressures within an area detector. With simple electronic readout methods, straw detector arrays can provide spatial resolution of 4 mm FWHM or better, and since an array detector of such form consists of several thousand individual elements per square meter, count rates in a 1 m^2 detector can reach 2?10^7 cps. Moreover, each individual event can be timetagged with a time resolution of less than 0.1 ?sec, allowing accurate identification of neutron energy by time of flight. Considering basic elemental cost, this novel neutron imaging detector can be commercially produced economically, probably at a small fraction of the cost of He-3 detectors. In addition to neutron scattering science, the fully developed base technology can be used as a rugged, low-cost neutron detector in area monitoring and surveying. Radiation monitors are used in a number of other settings for occupational and environmental radiation safety. Such a detector can also be used in environmental monitoring and remote nuclear power plant monitoring. For example, the Department of Energy could use it to characterize nuclear waste dumps, coordinate clean-up efforts, and assess the radioactive contaminants in the air and water. Radiation monitors can be used to monitor the age and component breakdown of nuclear warheads and to distinguish between weapons and reactor grade plutonium. The UN's International Atomic Energy Agency (IAEA) uses radiation monitors for treaty verification, remote monitoring, and enforcing the non-proliferation of nuclear weapons. As part of treaty verification, monitors can be used to certify the contents of containers during inspections. They could be used for portal monitoring to secure border checkpoints, sea ports, air cargo centers, public parks, sporting venues, and key government buildings. Currently, only 2% of all sea cargo shipped is inspected for radiation sources. In addition, merely the presence of radiation is detected and nothing is known about the radioactive source until further testing. The utilization of radiation monitors with neutron sensitivity and capability of operation in hostile port environments would increase the capacity and effectiveness of the radioactive scanning processes.

  5. Large-area semi-transparent light-sensitive nanocrystal skins

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    -area UV/visible sensing in windows and facades of smart buildings. ©2012 Optical Society of America OCIS

  6. CARMA LARGE AREA STAR FORMATION SURVEY: STRUCTURE AND KINEMATICS OF DENSE GAS IN SERPENS MAIN

    SciTech Connect (OSTI)

    Lee, Katherine I.; Storm, Shaye; Mundy, Lee G.; Teuben, Peter; Pound, Marc W.; Salter, Demerese M.; Chen, Che-Yu; Fernández-López, Manuel; Looney, Leslie W.; Segura-Cox, Dominique; Rosolowsky, Erik; Arce, Héctor G.; Plunkett, Adele L.; Ostriker, Eve C.; Shirley, Yancy L.; Kwon, Woojin; Kauffmann, Jens; Tobin, John J.; Volgenau, N. H.; Tassis, Konstantinos; and others

    2014-12-20

    We present observations of N{sub 2}H{sup +} (J = 1 ? 0), HCO{sup +} (J = 1 ? 0), and HCN (J = 1 ? 0) toward the Serpens Main molecular cloud from the CARMA Large Area Star Formation Survey (CLASSy). We mapped 150 arcmin{sup 2} of Serpens Main with an angular resolution of ?7''. The gas emission is concentrated in two subclusters (the NW and SE subclusters). The SE subcluster has more prominent filamentary structures and more complicated kinematics compared to the NW subcluster. The majority of gas in the two subclusters has subsonic to sonic velocity dispersions. We applied a dendrogram technique with N{sub 2}H{sup +}(1-0) to study the gas structures; the SE subcluster has a higher degree of hierarchy than the NW subcluster. Combining the dendrogram and line fitting analyses reveals two distinct relations: a flat relation between nonthermal velocity dispersion and size, and a positive correlation between variation in velocity centroids and size. The two relations imply a characteristic depth of 0.15 pc for the cloud. Furthermore, we have identified six filaments in the SE subcluster. These filaments have lengths of ?0.2 pc and widths of ?0.03 pc, which is smaller than a characteristic width of 0.1 pc suggested by Herschel observations. The filaments can be classified into two types based on their properties. The first type, located in the northeast of the SE subcluster, has larger velocity gradients, smaller masses, and nearly critical mass-per-unit-length ratios. The other type, located in the southwest of the SE subcluster, has the opposite properties. Several YSOs are formed along two filaments which have supercritical mass per unit length ratios, while filaments with nearly critical mass-per-unit-length ratios are not associated with YSOs, suggesting that stars are formed on gravitationally unstable filaments.

  7. Large Area Silicon Tracking Detectors with Fast Signal Readout for the Large Hadron Collider (LHC) at CERN

    E-Print Network [OSTI]

    Köstner, S

    2005-01-01

    The Standard Model of elementary particles, which is summarized briefly in the second chapter, incorporates a number of successful theories to explain the nature and consistency of matter. However not all building blocks of this model could yet be tested by experiment. To confirm existing theories and to improve nowadays understanding of matter a new machine is currently being built at CERN, the Large Hadron Collider (LHC), described in the third chapter. LHC is a proton-proton collider which will reach unprecedented luminosities and center of mass energies. Five experiments are attached to it to give answers to questions like the existence of the Higgs meson, which allows to explain the mass content of matter, and the origin of CP-violation, which plays an important role in the baryogenesis of the universe. Supersymmetric theories, proposing a bosonic superpartner for each fermion and vice versa, will be tested. By colliding heavy ions, high energy and particle densities can be achieved and probed. This stat...

  8. Comparing NEO Search Telescopes

    E-Print Network [OSTI]

    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...

  9. Method of making large area conformable shape structures for detector/sensor applications using glass drawing technique and postprocessing

    DOE Patents [OSTI]

    Ivanov, Ilia N. (Knoxville, TN); Simpson, John T. (Clinton, IN)

    2012-01-24

    A method of making a large area conformable shape structure comprises drawing a plurality of tubes to form a plurality of drawn tubes, and cutting the plurality of drawn tubes into cut drawn tubes of a predetermined shape. The cut drawn tubes have a first end and a second end along the longitudinal direction of the cut drawn tubes. The method further comprises conforming the first end of the cut drawn tubes into a predetermined curve to form the large area conformable shape structure, wherein the cut drawn tubes contain a material.

  10. Large-area submicron replica molding of porous low-k dielectric films and application to photonic crystal biosensor fabrication

    E-Print Network [OSTI]

    Cunningham, Brian

    Large-area submicron replica molding of porous low-k dielectric films and application to photonic Abstract We demonstrate a replica-molding method for submicron patterning of a low-index sol­gel nanoporous biosensors. Scanning electron micrographs show the sol­gel exhibited minimal shrinkage and good substrate

  11. Large-sensitive-area superconducting nanowire single-photon detector at 850 nm with high detection efficiency

    E-Print Network [OSTI]

    Li, Hao; You, Lixing; Yang, Xiaoyan; Zhang, Weijun; Liu, Xiaoyu; Chen, Sijing; Wang, Zhen; Xie, Xiaoming

    2015-01-01

    Satellite-ground quantum communication requires single-photon detectors of 850-nm wavelength with both high detection efficiency and large sensitive area. We developed superconducting nanowire single-photon detectors (SNSPDs) on one-dimensional photonic crystals, which acted as optical cavities to enhance the optical absorption, with a sensitive-area diameter of 50 um. The fabricated multimode fiber coupled NbN SNSPDs exhibited a maximum system detection efficiency (DE) of up to 82% and a DE of 78% at a dark count rate of 100 Hz at 850-nm wavelength as well as a system jitter of 105 ps.

  12. Large

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACTThousand CubicResourcelogo and mastheadLakeLanguage of a fly provesLarge

  13. Semiconductor-based, large-area, flexible, electronic devices on {110}<100> oriented substrates

    DOE Patents [OSTI]

    Goyal, Amit

    2014-08-05

    Novel articles and methods to fabricate the same resulting in flexible, oriented, semiconductor-based, electronic devices on {110}<100> textured substrates are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  14. On the possibility of the multiple inductively coupled plasma and helicon plasma sources for large-area processes

    SciTech Connect (OSTI)

    Lee, Jin-Won; Lee, Yun-Seong Chang, Hong-Young; An, Sang-Hyuk

    2014-08-15

    In this study, we attempted to determine the possibility of multiple inductively coupled plasma (ICP) and helicon plasma sources for large-area processes. Experiments were performed with the one and two coils to measure plasma and electrical parameters, and a circuit simulation was performed to measure the current at each coil in the 2-coil experiment. Based on the result, we could determine the possibility of multiple ICP sources due to a direct change of impedance due to current and saturation of impedance due to the skin-depth effect. However, a helicon plasma source is difficult to adapt to the multiple sources due to the consistent change of real impedance due to mode transition and the low uniformity of the B-field confinement. As a result, it is expected that ICP can be adapted to multiple sources for large-area processes.

  15. Research on stable, high-efficiency, large-area, amorphous-silicon-based submodules

    SciTech Connect (OSTI)

    Delahoy, A.E.; Tonon, T.; Macneil, J. (Chronar Corp., Princeton, NJ (USA))

    1991-06-01

    The primary objective of this subcontract is to develop the technology for same bandgap, amorphous silicon tandem junction photovoltaic modules having an area of at least 900 cm{sup 2} with the goal of achieving an aperture area efficiency of 9%. A further objective is to demonstrate modules that retain 95% of their under standard light soaking conditions. Our approach to the attainment of these objective is based on the following distinctive technologies: (a) in-house deposition of SiO{sub 2}/SnO{sub 2}:F onto soda lime glass by APCVD to provide a textured, transparent electrode, (b) single chamber r.f. flow discharge deposition of the a-Si:H layers onto vertical substrates contained with high package density in a box carrier'' to which the discharge is confined (c) sputter deposition of highly reflecting, ZnO-based back contacts, and (d) laser scribing of the a-Si:H and electrodes with real-time scribe tracking to minimize area loss. Continued development of single junction amorphous silicon was aggressively pursued as proving ground for various optical enhancement schemes, new p-layers, and i-layers quality. We have rigorously demonstrated that the introduction of a transitional i-layer does not impair stability and that the initial gain in performance is retained. We have demonstrated a small improvement in cell stability through a post-fabrication treatment consisting of multiple, intense light flashes followed by sufficient annealing. Finally, several experiments have indicated that long term stability can be improved by overcoating the SnO{sub 2} with ZnO. 25 refs., 17 figs.

  16. Development of a large area gas photomultiplier with GEM/$?$PIC

    E-Print Network [OSTI]

    H. Sekiya

    2008-10-06

    We are developing a new photon detector with micro pattern gaseous detectors. A semitransparent CsI photocathode is combined with 10cm$\\times$10cm GEM/$\\mu$PIC for the first prototype which is aimed for the large liquid Xe detectors. Using Ar+C$_2$H$_6$ (10%) gas, we achieved the gas gain of $10^5$ which is enough to detect single photoelectron. We, then, irradiated UV photons from a newly developed solid scintillator, LaF$_3$(Nd), to the detector and successfully detected single photoelectron.

  17. Testing and evaluation of large-area heliostats for solar thermal applications

    SciTech Connect (OSTI)

    Strachan, J.W.; Houser, R.M.

    1993-02-01

    Two heliostats representing the state-of-the-art in glass-metal designs for central receiver (and photovoltaic tracking) applications were tested and evaluated at the National Solar Thermal Test Facility in Albuquerque, New Mexico from 1986 to 1992. These heliostats have collection areas of 148 and 200 m{sup 2} and represent low-cost designs for heliostats that employ glass-metal mirrors. The evaluation encompassed the performance and operational characteristics of the heliostats, and examined heliostat beam quality, the effect of elevated winds on beam quality, heliostat drives and controls, mirror module reflectance and durability, and the overall operational and maintenance characteristics of the two heliostats. A comprehensive presentation of the results of these and other tests is presented. The results are prefaced by a review of the development (in the United States) of heliostat technology.

  18. Management of Large-Scale Wireless Sensor Networks Utilizing Multi-Parent Recursive Area Hierarchies

    SciTech Connect (OSTI)

    Cree, Johnathan V.; Delgado-Frias, Jose

    2013-04-19

    Autonomously configuring and self-healing a largescale wireless sensor network requires a light-weight maintenance protocol that is scalable. Further, in a battery powered wireless sensor network duty-cycling a node’s radio can reduce the power consumption of a device and extend the lifetime of a network. With duty-cycled nodes the power consumption of a node’s radio depends on the amount of communication is must perform and by reducing the communication the power consumption can also be reduced. Multi-parent hierarchies can be used to reduce the communication cost when constructing a recursive area clustering hierarchy when compared to singleparent solutions that utilize inefficient communication methods such as flooding and information propagation via single-hop broadcasts. The multi-parent hierarchies remain scalable and provides a level of redundancy for the hierarchy.

  19. Apparatus and method for rapid cooling of large area substrates in vacuum

    DOE Patents [OSTI]

    Barth, Kurt L.; Enzenroth, Robert A.; Sampath, Walajabad S.

    2012-11-06

    The present invention is directed to an apparatus and method for rapid cooling of a large substrate in a vacuum environment. A first cooled plate is brought into close proximity with one surface of a flat substrate. The spatial volume between the first cooling plate and the substrate is sealed and brought to a higher pressure than the surrounding vacuum level to increase the cooling efficiency. A second cooled plate is brought into close proximity with the opposite surface of the flat substrate. A second spatial volume between the second cooling plate and the substrate is sealed and the gas pressure is equalized to the gas pressure in the first spatial volume. The equalization of the gas pressure on both sides of the flat substrate eliminates deflection of the substrate and bending stress in the substrate.

  20. Apparatus and method for rapid cooling of large area substrates in vacuum

    DOE Patents [OSTI]

    Barth, Kurt L.; Enzenroth, Robert A.; Sampath, Walajabad S.

    2010-09-28

    The present invention is directed to an apparatus and method for rapid cooling of a large substrate in a vacuum environment. A first cooled plate is brought into close proximity with one surface of a flat substrate. The spatial volume between the first cooling plate and the substrate is sealed and brought to a higher pressure than the surrounding vacuum level to increase the cooling efficiency. A second cooled plate is brought into close proximity with the opposite surface of the flat substrate. A second spatial volume between the second cooling plate and the substrate is sealed and the gas pressure is equalized to the gas pressure in the first spatial volume. The equalization of the gas pressure on both sides of the flat substrate eliminates deflection of the substrate and bending stress in the substrate.

  1. Development of Large Area Gas Electron Multiplier Detector and Its Application to a Digital Hadron Calorimeter for Future Collider Experiments

    SciTech Connect (OSTI)

    Yu, Jaehoon; White, Andrew

    2014-09-25

    The UTA High Energy Physics Group conducted generic detector development based on large area, very thin and high sensitivity gas detector using gas electron multiplier (GEM) technology. This is in preparation for a use as a sensitive medium for sampling calorimeters in future collider experiments at the Energy Frontier as well as part of the tracking detector in Intensity Frontier experiments. We also have been monitoring the long term behavior of one of the prototype detectors (30cmx30cm) read out by the SLAC-developed 13-bit KPiX analog chip over three years and have made presentations of results at various APS meetings. While the important next step was the development of large area (1m x 1m) GEM planes, we also have looked into opportunities of applying this technology to precision tracking detectors to significantly improve the performance of the Range Stack detector for CP violation experiments and to provide an amplification layer for the liquid Argon Time Projection Chamber in the LBNE experiment. We have jointly developed 33cmx100cm large GEM foils with the CERN gas detector development group to construct 33cm x100cm unit chambers. Three of these unit chambers will be put together to form a 1m x 1m detector plane. Following characterization of one 33cmx100cm unit chamber prototype, a total of five 1m x 1m planes will be constructed and inserted into an existing 1m3 RPC DHCAL stack to test the performance of the new GEM DHCAL in particle beams. The large area GEM detector we planned to develop in this proposal not only gives an important option to DHCAL for future collider experiments but also the potential to expand its use to Intensity Frontier and Cosmic Frontier experiments as high efficiency, high amplification anode planes for liquid Argon time projection chambers. Finally, thanks to its sensitivity to X-rays and other neutral radiations and its light-weight characteristics, the large area GEM has a great potential for the use in medical imaging and homeland security, as well as satellite based astronomy experiments.

  2. Installation and commissioning of a large area coating system for neutron and X-ray optical devices

    SciTech Connect (OSTI)

    Biswas, A. Haque, Sk. Maidul Misal, J. Sampathkumar, R.; Ajaykumar,; Bhattacharyya, D.; Sahoo, N. K.; Lagoo, K. D.; Veerapur, R. D.; Padmanabhan, M.; Puri, R. K.; Bhattacharya, Debarati

    2014-04-24

    A 9 meter long DC/RF sputtering cylindrical coating system which is designed and built indigenously for coating of neutron supermirrors and grazing incidence hard X-ray mirrors on large area substrates has been installed and commissioned recently. The performance of the system has been tested by depositing Ti films on glass substrate of 1500mm X 150mm size. By depositing Ti films on several small area c-Si substrates placed over the length and breadth of the substrate holder, and by subsequent characterization by GIXR measurement, it has been observed that films with bulk-like density and very low surface roughness can be obtained in the above system. The thickness uniformity achieved in the deposited films is within ±3.5% over the 1500mm length and within ±4.8% over the 150mm width.

  3. Method for preparing ultraflat, atomically perfect areas on large regions of a crystal surface by heteroepitaxy deposition

    DOE Patents [OSTI]

    El Gabaly, Farid; Schmid, Andreas K.

    2013-03-19

    A novel method of forming large atomically flat areas is described in which a crystalline substrate having a stepped surface is exposed to a vapor of another material to deposit a material onto the substrate, which material under appropriate conditions self arranges to form 3D islands across the substrate surface. These islands are atomically flat at their top surface, and conform to the stepped surface of the substrate below at the island-substrate interface. Thereafter, the deposited materials are etched away, in the etch process the atomically flat surface areas of the islands transferred to the underlying substrate. Thereafter the substrate may be cleaned and annealed to remove any remaining unwanted contaminants, and eliminate any residual defects that may have remained in the substrate surface as a result of pre-existing imperfections of the substrate.

  4. Assessment of Systematic Chromatic Errors that Impact Sub-1% Photometric Precision in Large-Area Sky Surveys

    E-Print Network [OSTI]

    Li, T S; Marshall, J L; Tucker, D; Kessler, R; Annis, J; Bernstein, G M; Boada, S; Burke, D L; Finley, D A; James, D J; Kent, S; Lin, H; Marriner, J; Mondrik, N; Nagasawa, D; Rykoff, E S; Scolnic, D; Walker, A R; Wester, W; Abbott, T M C; Allam, S; Benoit-Lévy, A; Bertin, E; Brooks, D; Capozzi, D; Rosell, A Carnero; Kind, M Carrasco; Carretero, J; Crocce, M; Cunha, C E; D'Andrea, C B; da Costa, L N; Desai, S; Diehl, H T; Doel, P; Flaugher, B; Fosalba, P; Frieman, J; Gaztanaga, E; Goldstein, D A; Gruen, D; Gruendl, R A; Gutierrez, G; Honscheid, K; Kuehn, K; Kuropatkin, N; Maia, M A G; Melchior28, P; Miller, C J; Miquel, R; Mohr, J J; Neilsen, E; Nichol, R C; Nord, B; Ogando, R; Plazas, A A; Romer, A K; Roodman, A; Sako, M; Sanchez, E; Scarpine, V; Schubnell, M; Sevilla-Noarbe, I; Smith, R C; Soares-Santos, M; Sobreira, F; Suchyta, E; Tarle, G; Thomas, D; Vikram, V

    2016-01-01

    Meeting the science goals for many current and future ground-based optical large-area sky surveys requires that the calibrated broadband photometry is stable in time and uniform over the sky to 1% precision or better. Past surveys have achieved photometric precision of 1-2% by calibrating the survey's stellar photometry with repeated measurements of a large number of stars observed in multiple epochs. The calibration techniques employed by these surveys only consider the relative frame-by-frame photometric zeropoint offset and the focal plane position-dependent illumination corrections, which are independent of the source color. However, variations in the wavelength dependence of the atmospheric transmission and the instrumental throughput induce source color-dependent systematic errors. These systematic errors must also be considered to achieve the most precise photometric measurements. In this paper, we examine such systematic chromatic errors using photometry from the Dark Energy Survey (DES) as an example...

  5. Rapid production of large-area deep sub-wavelength hybrid structures by femtosecond laser light-field tailoring

    SciTech Connect (OSTI)

    Wang, Lei; Chen, Qi-Dai E-mail: hbsun@jlu.edu.cn; Yang, Rui; Xu, Bin-Bin; Wang, Hai-Yu; Yang, Hai; Huo, Cheng-Song; Tu, Hai-Ling; Sun, Hong-Bo E-mail: hbsun@jlu.edu.cn

    2014-01-20

    The goal of creation of large-area deep sub-wavelength nanostructures by femtosecond laser irradiation onto various materials is being hindered by the limited coherence length. Here, we report solution of the problem by light field tailoring of the incident beam with a phase mask, which serves generation of wavelets. Direct interference between the wavelets, here the first-order diffracted beams, and interference between a wavelet and its induced waves such as surface plasmon polariton are responsible for creation of microgratings and superimposed nanogratings, respectively. The principle of wavelets interference enables extension of uniformly induced hybrid structures containing deep sub-wavelength nanofeatures to macro-dimension.

  6. Recent progress in the development of large area silica aerogel for use as RICH radiator in the Belle II experiment

    E-Print Network [OSTI]

    Tabata, Makoto; Kawai, Hideyuki; Nishida, Shohei; Sumiyoshi, Takayuki

    2014-01-01

    We report recent progress in the development of large-area hydrophobic silica aerogels for use as radiators in the aerogel-based ring-imaging Cherenkov (A-RICH) counter to be installed in the forward end cap of the Belle II detector, which is currently being upgraded at the High Energy Accelerator Research Organization (KEK), Japan. The production of approximately 450 aerogel tiles with refractive indices of either 1.045 or 1.055 was completed in May, 2014, and the tiles are now undergoing optical characterization. Installation of the aerogels was tested by installing them into a partial mock-up of the support structure.

  7. Recent progress in the development of large area silica aerogel for use as RICH radiator in the Belle II experiment

    E-Print Network [OSTI]

    Makoto Tabata; Ichiro Adachi; Hideyuki Kawai; Shohei Nishida; Takayuki Sumiyoshi

    2014-11-16

    We report recent progress in the development of large-area hydrophobic silica aerogels for use as radiators in the aerogel-based ring-imaging Cherenkov (A-RICH) counter to be installed in the forward end cap of the Belle II detector, which is currently being upgraded at the High Energy Accelerator Research Organization (KEK), Japan. The production of approximately 450 aerogel tiles with refractive indices of either 1.045 or 1.055 was completed in May, 2014, and the tiles are now undergoing optical characterization. Installation of the aerogels was tested by installing them into a partial mock-up of the support structure.

  8. Neutrino Telescope Array Letter of Intent: A Large Array of High Resolution Imaging Atmospheric Cherenkov and Fluorescence Detectors for Survey of Air-showers from Cosmic Tau Neutrinos in the PeV-EeV Energy Range

    E-Print Network [OSTI]

    Makoto Sasaki; George Wei-Shu Hou

    2015-07-22

    This Letter of Intent (LoI) describes the outline and plan for the Neutrino Telescope Array (NTA) project. High-energy neutrinos provide unique and indisputable evidence for hadronic acceleration. Recently, IceCube has reported astronomical neutrino candidates in excess of expectation from atmospheric secondaries, but is limited by the water Cherenkov detection method. A next generation high-energy neutrino telescope should be capable of establishing indisputable evidence for cosmic high-energy neutrinos. It should not only have orders-of-magnitude larger sensitivity, but also enough pointing accuracy to probe known or unknown astronomical objects, without suffering from atmospheric secondaries. The proposed installation is a large array of compound eye stations of imaging atmospheric Cherenkov and fluorescence detectors, with wide field of view and refined observational ability of air showers from cosmic tau neutrinos in the PeV-EeV energy range. This advanced optical complex system is based substantially on the development of All-sky Survey High Resolution Air-shower detector (Ashra) and applies the tau shower Earth-skimming method to survey PeV-EeV tau neutrinos. It allows wide (30 deg x 360 deg) and deep (~400 Mpc) survey observation for PeV-EeV tau neutrinos assuming the standard GRB neutrino fluence.In addition, it enjoys the pointing accuracy of better than 0.2 deg in essentially background-free conditions. With the advanced imaging of Earth-skimming tau showers in the wide field of view, we aim for clear discovery and identification of astronomical tau neutrino sources, providing inescapable evidence of the astrophysical hadronic model for acceleration and/or propagation of extremely high energy protons in the precisely determined direction.

  9. Ion implantation for figure correction of high-resolution x-ray telescope mirrors

    E-Print Network [OSTI]

    Chalifoux, Brandon D

    2014-01-01

    Fabricating mirrors for future high-resolution, large-aperture x-ray telescopes continues to challenge the x-ray astronomy instrumentation community. Building a large-aperture telescope requires thin, lightweight mirrors; ...

  10. Phosphate single mode large mode area all-solid photonic crystal fiber with multi-watt output power

    SciTech Connect (OSTI)

    Wang, Longfei; He, Dongbing; Yu, Chunlei; Hu, Lili; Chen, Danping, E-mail: dpchen2008@aliyun.com [Key Laboratory of High Power Laser Materials, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Liu, Hui [Navigation Staff Room, Anhui Bengbu Petty Officer Academy of Navy, Bengbu 233000 (China); Qiu, Jianrong [Institute of Optical Communication Materials, South China University of Technology, Guangzhou 510641 (China)

    2014-03-31

    An index-depressed active core, single-mode phosphate all-solid large-mode-area photonic crystal fiber (PCF) is theoretically investigated using full-vectorial finite difference approach and experimentally realized. The PCF has a maximum output power of 5.4?W and 31% slope efficiency. Single-mode operation is realized through PCFs with core diameters of 30, 35, and 40??m, respectively. The beam quality is not degraded even at maximum output power. Our simulations and experiments reveal that the laser performance is significantly affected by the center-to-center distance between the two nearest rods ?, the rod diameter d, and their ratio d/?, implying that much attention should be given in employing optimal parameters to achieve excellent laser performance.

  11. Cyclododecane as support material for clean and facile transfer of large-area few-layer graphene

    SciTech Connect (OSTI)

    Capasso, A.; Leoni, E.; Dikonimos, T.; Buonocore, F.; Lisi, N. [ENEA, Materials Technology Unit, Surface Technology Laboratory, Casaccia Research Centre, Via Anguillarese 301, 00060 Rome (Italy); De Francesco, M. [ENEA, Technical Unit for Renewable Energies Sources, Casaccia Research Center, Via Anguillarese 301, 00060 Rome (Italy); Lancellotti, L.; Bobeico, E. [ENEA, Portici Research Centre, P.le E. Fermi 1, 80055 Portici (Italy); Sarto, M. S.; Tamburrano, A.; De Bellis, G. [Research Center on Nanotechnology Applied to Engineering of Sapienza (CNIS), SSNLab, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome (Italy)

    2014-09-15

    The transfer of chemical vapor deposited graphene is a crucial process, which can affect the quality of the transferred films and compromise their application in devices. Finding a robust and intrinsically clean material capable of easing the transfer of graphene without interfering with its properties remains a challenge. We here propose the use of an organic compound, cyclododecane, as a transfer material. This material can be easily spin coated on graphene and assist the transfer, leaving no residues and requiring no further removal processes. The effectiveness of this transfer method for few-layer graphene on a large area was evaluated and confirmed by microscopy, Raman spectroscopy, x-ray photoemission spectroscopy, and four-point probe measurements. Schottky-barrier solar cells with few-layer graphene were fabricated on silicon wafers by using the cyclododecane transfer method and outperformed reference cells made by standard methods.

  12. Early Science with the Large Millimeter Telescope: CO and [C II] Emission in the z=4.3 AzTEC J095942.9+022938 (COSMOS AzTEC-1)

    E-Print Network [OSTI]

    Yun, Min S; Gurwell, M A; Hughes, D H; Montaña, A; Narayanan, G; González, D Rosa; Sánchez-Argüelles, D; Schloerb, F P; Snell, R L; Vega, O; Wilson, G W; Zeballos, M; Chavez, M; Cybulski, J R; Díaz-Santos, T; De la Luz, V; Erickson, N; Ferrusca, D; Gim, H B; Heyer, M H; Iono, D; Pope, A; Rogstad, S M; Scott, K S; Souccar, K; Terlevich, E; Terlevich, R; Wilner, D; Zavala, J A

    2015-01-01

    Measuring redshifted CO line emission is an unambiguous method for obtaining an accurate redshift and total cold gas content of optically faint, dusty starburst systems. Here, we report the first successful spectroscopic redshift determination of AzTEC J095942.9+022938 ("COSMOS AzTEC-1"), the brightest 1.1mm continuum source found in the AzTEC/JCMT survey (Scott et al. 2008), through a clear detection of the redshifted CO (4-3) and CO (5-4) lines using the Redshift Search Receiver on the Large Millimeter Telescope. The CO redshift of $z=4.3420\\pm0.0004$ is confirmed by the detection of the redshifted 158 micron [C II] line using the Submillimeter Array. The new redshift and Herschel photometry yield $L_{FIR}=(1.1\\pm0.1)\\times 10^{13} L_\\odot$ and $SFR = 1300\\, M_\\odot$ yr$^{-1}$. Its molecular gas mass derived using the ULIRG conversion factor is $1.4\\pm0.2 \\times 10^{11} M_\\odot$ while the total ISM mass derived from the 1.1mm dust continuum is $3.7\\pm0.7 \\times 10^{11} M_\\odot$ assuming dust temperature of ...

  13. Cherenkov Telescope Array Data Management

    E-Print Network [OSTI]

    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.

  14. METAMATERIALS: Large-area printed 3D negative-index metamaterial is flexible -Laser Focus World http://www.laserfocusworld.com/articles/print/volume-47/issue-8/world-news/metamaterials-large-area-printed-3d-negative-index-metamaterial-is-flexible.html[8/1

    E-Print Network [OSTI]

    Rogers, John A.

    METAMATERIALS: Large-area printed 3D negative-index metamaterial is flexible - Laser Focus World http://www.laserfocusworld.com/articles/print/volume-47/issue-8/world-news/metamaterials-large-area-printed-3d-negative-index-metamaterial-is-flexible.html[8/12/2011 3:45:06 PM] About · Advertise · Advertise

  15. Studies of an array of PbF2 Cherenkov crystals with large-area SiPM readout

    E-Print Network [OSTI]

    A. T. Fienberg; L. P. Alonzi; A. Anastasi; R. Bjorkquist; D. Cauz; R. Fatemi; C. Ferrari; A. Fioretti; A. Frankenthal; C. Gabbanini; L. K. Gibbons; K. Giovanetti; S. D. Goadhouse; W. P. Gohn; T. P. Gorringe; D. W. Hertzog; M. Iacovacci; P. Kammel; J. Kaspar; B. Kiburg; L. Li; S. Mastroianni; G. Pauletta; D. A. Peterson; D. Pocanic; M. W. Smith; D. A. Sweigart; V. Tishchenko; G. Venanzoni; T. D. Van Wechel; K. B. Wall; P. Winter; K. Yai

    2015-02-19

    The electromagnetic calorimeter for the new muon (g-2) experiment at Fermilab will consist of arrays of PbF2 Cherenkov crystals read out by large-area silicon photo-multiplier (SiPM) sensors. We report here on measurements and simulations using 2.0 -- 4.5 GeV electrons with a 28-element prototype array. All data were obtained using fast waveform digitizers to accurately capture signal pulse shapes versus energy, impact position, angle, and crystal wrapping. The SiPMs were gain matched using a laser-based calibration system, which also provided a stabilization procedure that allowed gain correction to a level of 1e-4 per hour. After accounting for longitudinal fluctuation losses, those crystals wrapped in a white, diffusive wrapping exhibited an energy resolution sigma/E of (3.4 +- 0.1) % per sqrt(E/GeV), while those wrapped in a black, absorptive wrapping had (4.6 +- 0.3) % per sqrt(E/GeV). The white-wrapped crystals---having nearly twice the total light collection---display a generally wider and impact-position-dependent pulse shape owing to the dynamics of the light propagation, in comparison to the black-wrapped crystals, which have a narrower pulse shape that is insensitive to impact position.

  16. LARGE-AREA [Fe II] LINE MAPPING OF THE SUPERNOVA REMNANT IC 443 WITH THE IRSF/SIRIUS

    SciTech Connect (OSTI)

    Kokusho, Takuma; Nagayama, Takahiro; Kaneda, Hidehiro; Ishihara, Daisuke [Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602 (Japan); Lee, Ho-Gyu; Onaka, Takashi, E-mail: kokusho@u.phys.nagoya-u.ac.jp [Department of Astronomy, Graduate School of Science, University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2013-05-01

    We present the results of near-infrared (near-IR) [Fe II] line mapping of the supernova remnant IC 443 with IRSF/SIRIUS, using the two narrow-band filters tuned for the [Fe II] 1.257 {mu}m and [Fe II] 1.644 {mu}m lines. Covering a large area of 30' Multiplication-Sign 35', our observations reveal that [Fe II] filamentary structures exist all over the remnant, not only in an ionic shock shell, but also in a molecular shock shell and a central region inside the shells. With the two [Fe II] lines, we performed corrections for dust extinction to derive the intrinsic line intensities. We also obtained the intensities of thermal emission from the warm dust associated with IC 443, using the far- and mid-IR images taken with AKARI and Spitzer, respectively. As a result, we find that the [Fe II] line emission relative to the dust emission notably enhances in the inner central region. We discuss causes of the enhanced [Fe II] line emission, estimating the Fe{sup +} and dust masses.

  17. Firenze 2001: Silicon Detectors Hartmut F.-W. Sadrozinski , SCIPP, UC Santa Cruz Large-Scale

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Firenze 2001: Silicon Detectors Hartmut F.-W. Sadrozinski , SCIPP, UC Santa Cruz SCIPPSCIPP Large (SCIPP) Development of Silicon Detectors GLAST : ·Gamma-Ray ·Large Area ·Space Telescope #12;Firenze 2001 by wafer size: 4" & 6" => Ladders #12;Firenze 2001: Silicon Detectors Hartmut F.-W. Sadrozinski , SCIPP, UC

  18. CARMA Large Area Star Formation Survey: project overview with analysis of dense gas structure and kinematics in Barnard 1

    SciTech Connect (OSTI)

    Storm, Shaye; Mundy, Lee G.; Lee, Katherine I.; Teuben, Peter; Pound, Marc W.; Salter, Demerese M.; Chen, Che-Yu; Gong, Hao; Fernández-López, Manuel; Looney, Leslie W.; Segura-Cox, Dominique M.; Rosolowsky, Erik; Arce, Héctor G.; Plunkett, Adele L.; Ostriker, Eve C.; Volgenau, Nikolaus H.; Shirley, Yancy L.; Tobin, John J.; Kwon, Woojin; Isella, Andrea; and others

    2014-10-20

    We present details of the CARMA Large Area Star Formation Survey (CLASSy), while focusing on observations of Barnard 1. CLASSy is a CARMA Key Project that spectrally imaged N{sub 2}H{sup +}, HCO{sup +}, and HCN (J = 1 ? 0 transitions) across over 800 square arcminutes of the Perseus and Serpens Molecular Clouds. The observations have angular resolution near 7'' and spectral resolution near 0.16 km s{sup –1}. We imaged ?150 square arcminutes of Barnard 1, focusing on the main core, and the B1 Ridge and clumps to its southwest. N{sub 2}H{sup +} shows the strongest emission, with morphology similar to cool dust in the region, while HCO{sup +} and HCN trace several molecular outflows from a collection of protostars in the main core. We identify a range of kinematic complexity, with N{sub 2}H{sup +} velocity dispersions ranging from ?0.05 to 0.50 km s{sup –1} across the field. Simultaneous continuum mapping at 3 mm reveals six compact object detections, three of which are new detections. A new, non-binary dendrogram algorithm is used to analyze dense gas structures in the N{sub 2}H{sup +} position-position-velocity (PPV) cube. The projected sizes of dendrogram-identified structures range from about 0.01 to 0.34 pc. Size-linewidth relations using those structures show that non-thermal line-of-sight velocity dispersion varies weakly with projected size, while rms variation in the centroid velocity rises steeply with projected size. Comparing these relations, we propose that all dense gas structures in Barnard 1 have comparable depths into the sky, around 0.1-0.2 pc; this suggests that overdense, parsec-scale regions within molecular clouds are better described as flattened structures rather than spherical collections of gas. Science-ready PPV cubes for Barnard 1 molecular emission are available for download.

  19. Large-scale spatial variability of riverbed temperature gradients in Snake River fall Chinook salmon spawning areas

    SciTech Connect (OSTI)

    Hanrahan, Timothy P.

    2007-02-01

    In the Snake River basin of the Pacific northwestern United States, hydroelectric dam operations are often based on the predicted emergence timing of salmon fry from the riverbed. The spatial variability and complexity of surface water and riverbed temperature gradients results in emergence timing predictions that are likely to have large errors. The objectives of this study were to quantify the thermal heterogeneity between the river and riverbed in fall Chinook salmon spawning areas and to determine the effects of thermal heterogeneity on fall Chinook salmon emergence timing. This study quantified river and riverbed temperatures at 15 fall Chinook salmon spawning sites distributed in two reaches throughout 160 km of the Snake River in Hells Canyon, Idaho, USA, during three different water years. Temperatures were measured during the fall Chinook salmon incubation period with self-contained data loggers placed in the river and at three different depths below the riverbed surface. At all sites temperature increased with depth into the riverbed, including significant differences (p<0.05) in mean water temperature of up to 3.8°C between the river and the riverbed among all the sites. During each of the three water years studied, river and riverbed temperatures varied significantly among all the study sites, among the study sites within each reach, and between sites located in the two reaches. Considerable variability in riverbed temperatures among the sites resulted in fall Chinook salmon emergence timing estimates that varied by as much as 55 days, depending on the source of temperature data used for the estimate. Monitoring of riverbed temperature gradients at a range of spatial scales throughout the Snake River would provide better information for managing hydroelectric dam operations, and would aid in the design and interpretation of future empirical research into the ecological significance of physical riverine processes.

  20. IEEE TRANSACTIONS ON VERY LARGE SCALE INTEGRATION (VLSI) SYSTEMS, VOL. 19, NO. 2, FEBRUARY 2011 305 Area-Efficient Scalable MAP Processor Design

    E-Print Network [OSTI]

    Wu, An-Yeu "Andy"

    with an energy efficiency of 0.19 nJ/bit and an area efficiency of 3.13 bits/mm2. For the multistandard systemsIEEE TRANSACTIONS ON VERY LARGE SCALE INTEGRATION (VLSI) SYSTEMS, VOL. 19, NO. 2, FEBRUARY 2011 305, such as worldwide interoperability for microwave access (WiMAX) [4]. Table I lists the detailed specifications

  1. High-Rate Fabrication of a-Si-Based Thin-Film Solar Cells Using Large-Area VHF PECVD Processes

    SciTech Connect (OSTI)

    Deng, Xunming; Fan, Qi Hua

    2011-12-31

    The University of Toledo (UT), working in concert with it’s a-Si-based PV industry partner Xunlight Corporation (Xunlight), has conducted a comprehensive study to develop a large-area (3ft x 3ft) VHF PECVD system for high rate uniform fabrication of silicon absorber layers, and the large-area VHF PECVD processes to achieve high performance a-Si/a-SiGe or a-Si/nc-Si tandem junction solar cells during the period of July 1, 2008 to Dec. 31, 2011, under DOE Award No. DE-FG36-08GO18073. The project had two primary goals: (i) to develop and improve a large area (3 ft × 3 ft) VHF PECVD system for high rate fabrication of > = 8 Å/s a-Si and >= 20 Å/s nc-Si or 4 Å/s a-SiGe absorber layers with high uniformity in film thicknesses and in material structures. (ii) to develop and optimize the large-area VHF PECVD processes to achieve high-performance a-Si/nc-Si or a-Si/a-SiGe tandem-junction solar cells with >= 10% stable efficiency. Our work has met the goals and is summarized in “Accomplishments versus goals and objectives”.

  2. Remote sensing of exposure to NO2: Satellite versus ground-based measurement in a large urban area

    E-Print Network [OSTI]

    Mlllet, Dylan B.

    area. Published by Elsevier Ltd. 1. Introduction Urban air pollution is one of the top 15 causes cardiopulmonary mortality (Beelen et al., 2008), lung cancer (Filleul et al., 2005), and asthma exacerbations

  3. A Medium Sized Schwarzschild-Couder Cherenkov Telescope Mechanical Design Proposed for the Cherenkov Telescope Array

    E-Print Network [OSTI]

    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.

  4. Impact of Potential Large-Scale Irrigation on the West African Monsoon and Its Dependence on Location of Irrigated Area

    E-Print Network [OSTI]

    Im, Eun-Soon

    This study investigates the impact of potential large-scale irrigation on the West African monsoon using the Massachusetts Institute of Technology regional climate model (MRCM). A new irrigation module is implemented to ...

  5. Chapter Fourteen Telescope Consortium

    E-Print Network [OSTI]

    Gustafsson, Torgny

    206 Chapter Fourteen Telescope Consortium Paul Leath (1995-2000) When Allen Robbins stepped down, and all other universities. Also in 1998, U.S. News & World Report ranked the Rutgers program 16th.S. in High Energy Elementary Particle Physics, 6th among public universities.4 This assessment was followed

  6. The "dead zone" is a large area of decreased dissolved oxygen concentration in bottom waters that forms

    E-Print Network [OSTI]

    Dodds, Walter

    that forms each summer in the northern Gulf of Mexico. This hypoxic zone (HZ) is formally defined as an area human activi- ties are loaded into the Gulf of Mexico via the Mississippi and Atchafalaya Rivers agricultural activities in the Mississippi River drainage basin and entering the Gulf of Mexico, was thought

  7. Digital Frequency Domain Multiplexer for mm-Wavelength Telescopes

    E-Print Network [OSTI]

    Dobbs, Matt

    2008-01-01

    for Large Scale Bolometer Arrays”, Monterey Far-IR, Sub-mmand mm Detector Technology Workshop proceedings, 2002, pp.Domain Multiplexer for mm-Wavelength Telescopes Matt Dobbs,

  8. Large-area, triple-junction a-Si alloy production scale-up. Semiannual subcontract report, 17 March 1994--18 September 1994

    SciTech Connect (OSTI)

    Oswald, R.; Morris, J. [Solarex Corp., Newtown, PA (United States). Thin Film Div.

    1995-09-01

    This report describes work performed under a 3-y subcontract to advance Solarex`s photovoltaic manufacturing technologies, reduce its a-Si:H module production costs, increase module performance, and expand the Solarex commercial production capacity. During this period, Solarex focused on improving deposition of the front contact, investigating alternate feedstocks for the front contact, maximizing throughput and area utilization for all laser scribes, optimizing a-Si:H deposition equipment to achieve uniform deposition over large areas, optimizing the triple-junction module fabrication process, evaluating the materials to deposit the rear contact, and optimizing the combination of isolation scribe and encapsulant to pass the wet high potential test.

  9. Prospects for Gamma-Ray Bursts detection by the Cherenkov Telescope Array

    E-Print Network [OSTI]

    ,

    2015-01-01

    The first Gamma-Ray Burst (GRB) catalog presented by the Fermi-Large Area Telescope (LAT) collaboration includes 28 GRBs, detected above 100 MeV over the first three years since the launch of the Fermi mission. However, more than 100 GRBs are expected to be found over a period of six years of data collection thanks to a new detection algorithm and to the development of a new LAT event reconstruction, the so-called "Pass 8." Our aim is to provide revised prospects for GRB alerts in the CTA era in light of these new LAT discoveries. We focus initially on the possibility of GRB detection with the Large Size Telescopes (LSTs). Moreover, we investigate the contribution of the Middle Size Telescopes (MSTs), which are crucial for the search of larger areas on short post trigger timescales. The study of different spectral components in the prompt and afterglow phase, and the limits on the Extragalactic background light are highlighted. Different strategies to repoint part of - or the entire array - are studied in det...

  10. Perspectives on neutrino telescopes 2009

    SciTech Connect (OSTI)

    Quigg, Chris; /Fermilab /Karlsruhe U., TTP

    2009-04-01

    Remarks at the roundtable on plans for the future at the XIII International Workshop on Neutrino Telescopes.

  11. {100}<100> or 45.degree.-rotated {100}<100>, semiconductor-based, large-area, flexible, electronic devices

    DOE Patents [OSTI]

    Goyal, Amit (Knoxville, TN)

    2012-05-15

    Novel articles and methods to fabricate the same resulting in flexible, {100}<100> or 45.degree.-rotated {100}<100> oriented, semiconductor-based, electronic devices are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  12. Progress on the 1.6-meter New Solar Telescope at Big Bear Solar Observatory

    E-Print Network [OSTI]

    of the drivers for building solar telescopes with large apertures. Recent advances in adaptive optics (AO) make it possible to build solar telescopes in an open configuration and thus go beyond the conventional meterProgress on the 1.6-meter New Solar Telescope at Big Bear Solar Observatory C. Denkera, P. R

  13. EST: the European Solar Telescope D. Kiselman, M. Lofdahl & G. Scharmer

    E-Print Network [OSTI]

    Löfdahl, Mats

    is to construct a new large-aperture solar telescope: the European Solar Telescope (EST). 3. EST design studyEST: the European Solar Telescope D. Kiselman, M. L¨ofdahl & G. Scharmer The Institute for Solar of solar magnetism is to measure the structure and dynamics of the magnetic field at the solar surface down

  14. OPENENDED CONFIGURATIONS OF RADIO TELESCOPES

    E-Print Network [OSTI]

    Kreinovich, Vladik

    telescopes, devices that use the second observability window of radio waves. Why configurations of radioOPEN­ENDED CONFIGURATIONS OF RADIO TELESCOPES: A GEOMETRICAL ANALYSIS Vladik Kreinovich, Scott A. The quality of radio astronomical images drastically depends on where we place the radio telescopes. During

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

    E-Print Network [OSTI]

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

    2008-02-29

    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.

  16. The ANTARES Neutrino Telescope

    E-Print Network [OSTI]

    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.

  17. Observations of the Isotropic Diffuse Gamma-ray Background with the EGRET Telescope

    E-Print Network [OSTI]

    T. D. Willis

    2002-01-30

    An Isotropic Diffuse Gamma-Ray Background (IDGRB) in the spectral range 30-10,000 MeV was first reported in the early 1970's using measurements made by the SAS-2 instrument. Data recorded by the Energetic Gamma Ray Experiment Telescope (EGRET) on board the Compton Gamma Ray Observatory (CGRO) over the last 4 years are analysed in order to extract the best measurement yet made of the IDGRB. Extensive analysis of the EGRET instrumental background is presented in order to demonstrate that an uncontaminated data set can be extracted from the EGRET data. A model of the high latitude galactic diffuse foreground emission is presented and the existence of an IDGRB is confirmed. Spatial and spectral analysis of this background is presented. In addition, point source analysis at high galactic latitudes is performed to reveal the existence of a population of extragalactic sources. The characteristics of this population are examined and models of its flux distribution are reported. The question of whether the IDGRB is composed of unresolved point sources is addressed using fluctuation analysis. Finally, possible future directions for gamma ray astronomy are examined through simulations of a future gamma ray telescope: the Gamma-ray Large Area Space Telescope (GLAST). The GLAST baseline design is described and its scientific performance is evaluated. The ability of this telescope to detect 1,000-10,000 new extragalactic sources is demonstrated and the likely impact on the study of the IDGRB is considered.

  18. The Animated Gamma-ray Sky Revealed by the Fermi Gamma-ray Space Telescope

    ScienceCinema (OSTI)

    Isabelle Grenier

    2010-01-08

    The Fermi Gamma-ray Space Telescope has been observing the sky in gamma-rays since August 2008.  In addition to breakthrough capabilities in energy coverage (20 MeV-300 GeV) and angular resolution, the wide field of view of the Large Area Telescope enables observations of 20% of the sky at any instant, and of the whole sky every three hours. It has revealed a very animated sky with bright gamma-ray bursts flashing and vanishing in minutes, powerful active galactic nuclei flaring over hours and days, many pulsars twinkling in the Milky Way, and X-ray binaries shimmering along their orbit. Most of these variable sources had not been seen by the Fermi predecessor, EGRET, and the wealth of new data already brings important clues to the origin of the high-energy emission and particles powered by the compact objects. The telescope also brings crisp images of the bright gamma-ray emission produced by cosmic-ray interactions in the interstellar medium, thus allowing to measure the cosmic nuclei and electron spectra across the Galaxy, to weigh interstellar clouds, in particular in the dark-gas phase. The telescope sensitivity at high energy will soon provide useful constraints on dark-matter annihilations in a variety of environments. I will review the current results and future prospects of the Fermi mission.

  19. An Innovative Approach for the Calculation of Exposure Point Concentrations for Large Areas of Surface Radionuclide Contamination

    SciTech Connect (OSTI)

    Winchester Chromec, F.; Myers, Jeffrey C.

    2008-01-15

    The Department of Energy Rocky Flats site was designated as a wildlife refuge by the Rocky Flats National Wildlife Refuge Act of 2001. Rocky Flats was considered to be one of the most highly contaminated radiological sites in the country. Some portions of the site have low-level radionuclide contamination in surface soils. A site-wide risk and dose assessment to evaluate threats to human health and the environment were performed, so that the site could be released for this land use. The aggressive accelerated action program combined with defensible and innovative risk assessment methods resulted in there being no radionuclides of concern in the final comprehensive risk assessment (DOE 2006). An innovative approach for delineating functional exposure areas and area-weighted exposure point concentration-activities (EPCs) was negotiated with the regulatory agencies in Colorado. This procedure leads to realistic estimates of risk and dose to workers and visitors. This innovative approach to the calculation of EPCs was negotiated with both State and Federal regulators. The value of developing and maintaining good working relationships with regulators responsible for a site can not be overestimated. The building of trust and confidence among responsible parties and regulators is essential for the development and implementation of innovative methods and technologies.

  20. Successfully Managing the Experimental Area of a Large Physics Experiment from Civil Engineering to the First Beams

    E-Print Network [OSTI]

    Butin, F

    2010-01-01

    The role of "Experimental Area Manager" supported by a well organized, charismatic and motivated team is absolutely essential for managing the huge effort needed for a multi-cultural, multi-disciplinary installation of cathedral-size underground caverns housing a billion dollar physics experiment. Between the years 2002 and 2008, we supervised and coordinated the ATLAS work site at LHC, from the end of the civil engineering to the first circulating beams, culminating with 240 workers on the site, 24 hours a day, 7 days a week, with activities taking place simultaneously on the surface, in the 60 m shafts and in the 100 m underground experimental cavern. We depict the activities preparation scheme (including tasks ranging from the installation of 280 ton cranes to super-delicate silicon detectors), the work-site organization method, the safety management that was a top priority throughout the whole project, and the opencommunication strategy that required maintaining permanent public visits. The accumulation o...

  1. Large-area Silicon-Film{trademark} panels and solar cells. Final technical report, July 1995--March 1998

    SciTech Connect (OSTI)

    Rand, J.A.; Bai, Y.; Barnett, A.M.; Culik, J.S.; Ford, D.H.; Hall, R.B.; Kendall, C.L.

    1998-09-01

    This report will detail substantial improvements in each of the task areas. A number of new products were developed, including a 130 kW array built using a new panel design. Improvements in laboratory-scale solar cell processing resulted in a confirmed efficiency of 16.6%. A new Silicon-Film{trademark} production sheet machine was built which increased throughput by 70%. Three solar cell fabrication processes were converted from low throughout batch processes to high throughput, continuous, belt processes. These new processes are capable of processing sheet over 31 cm in width. Finally, a new Silicon-Film{trademark} sheet machine was built that demonstrated a sheet width of 38 cm. This tool enabled AstroPower to demonstrate a wide range of solar cell sizes, many of which have generated considerable market interest.

  2. Parallel Configuration For Fast Superconducting Strip Line Detectors With Very Large Area In Time Of Flight Mass Spectrometry

    SciTech Connect (OSTI)

    Casaburi, A.; Zen, N.; Suzuki, K.; Ohkubo, M.; Ejrnaes, M.; Cristiano, R.; Pagano, S.

    2009-12-16

    We realized a very fast and large Superconducting Strip Line Detector based on a parallel configuration of nanowires. The detector with size 200x200 {mu}m{sup 2} recorded a sub-nanosecond pulse width of 700 ps in FWHM (400 ps rise time and 530 ps relaxation time) for lysozyme monomers/multimers molecules accelerated at 175 keV in a Time of Flight Mass Spectrometer. This record is the best in the class of superconducting detectors and comparable with the fastest NbN superconducting single photon detector of 10x10 {mu}m{sup 2}. We succeeded in acquiring mass spectra as the first step for a scale-up to {approx}mm pixel size for high throughput MS analysis, while keeping a fast response.

  3. First results of a large-area cryogenic gaseous photomultiplier coupled to a dual-phase liquid xenon TPC

    E-Print Network [OSTI]

    Arazi, L; Erdal, E; Israelashvili, I; Rappaport, M L; Shchemelinin, S; Vartsky, D; Santos, J M F dos; Breskin, A

    2015-01-01

    We discuss recent advances in the development of cryogenic gaseous photomultipliers (GPM), for possible use in dark matter and other rare-event searches using noble-liquid targets. We present results from a 10 cm diameter GPM coupled to a dual-phase liquid xenon (LXe) TPC, demonstrating - for the first time - the feasibility of recording both primary ("S1") and secondary ("S2") scintillation signals. The detector comprised a triple Thick Gas Electron Multiplier (THGEM) structure with cesium iodide photocathode on the first element; it was shown to operate stably at 180 K with gains above 10^5, providing high single-photon detection efficiency even in the presence of large alpha particle-induced S2 signals comprising thousands of photoelectrons. S1 scintillation signals were recorded with a time resolution of 1.2 ns (RMS). The energy resolution ({\\sigma}/E) for S2 electroluminescence of 5.5 MeV alpha particles was ~9%, which is comparable to that obtained in the XENON100 TPC with PMTs. The results are discusse...

  4. Large-area, triple-junction a-Si alloy production scale-up. Semiannual subcontract report, 17 March 1994--18 September 1994

    SciTech Connect (OSTI)

    Oswald, R.; Morris, J. [Solarex Corp., Newtown, PA (United States). Thin Film Div.

    1995-03-01

    This report describes work performed under a 3-year subcontract to advance Solarex`s photovoltaic (PV) manufacturing technologies, reduce its hydrogenated amorphous silicon (a-Si:H) module production costs, increase module performance, and expand the Solarex commercial production capacity. During the period covered by this report, Solarex focused on (1) improving deposition of the front contact, (2) investigating alternate feed stocks for the front contact, (3) maximizing throughput and area utilization for all laser scribes, (4) optimizing a-Si:H deposition equipment to achieve uniform deposition over large areas, (5) optimizing the triple-junction module fabrication process, (6) evaluating the materials to deposit the rear contact, and (7) optimizing the combination of isolation scribe and encapsulant to pass the wet high-potential test.

  5. Development of a mid-sized Schwarzschild-Couder Telescope for the Cherenkov Telescope Array

    SciTech Connect (OSTI)

    Cameron, Robert A.

    2012-06-28

    The Cherenkov Telescope Array (CTA) is a ground-based observatory for very high-energy (10 GeV to 100 TeV) gamma rays, planned for operation starting in 2018. It will be an array of dozens of optical telescopes, known as Atmospheric Cherenkov Telescopes (ACTs), of 8 m to 24 m diameter, deployed over an area of more than 1 square km, to detect flashes of Cherenkov light from showers initiated in the Earth's atmosphere by gamma rays. CTA will have improved angular resolution, a wider energy range, larger fields of view and an order of magnitude improvement in sensitivity over current ACT arrays such as H.E.S.S., MAGIC and VERITAS. Several institutions have proposed a research and development program to eventually contribute 36 medium-sized telescopes (9 m to 12 m diameter) to CTA to enhance and optimize its science performance. The program aims to construct a prototype of an innovative, Schwarzschild-Couder telescope (SCT) design that will allow much smaller and less expensive cameras and much larger fields of view than conventional Davies-Cotton designs, and will also include design and testing of camera electronics for the necessary advances in performance, reliability and cost. We report on the progress of the mid-sized SCT development program.

  6. Grid Integration of Robotic Telescopes

    E-Print Network [OSTI]

    F. Breitling; T. Granzer; H. Enke

    2009-03-23

    Robotic telescopes and grid technology have made significant progress in recent years. Both innovations offer important advantages over conventional technologies, particularly in combination with one another. Here, we introduce robotic telescopes used by the Astrophysical Institute Potsdam as ideal instruments for building a robotic telescope network. We also discuss the grid architecture and protocols facilitating the network integration that is being developed by the German AstroGrid-D project. Finally, we present three user interfaces employed for this purpose.

  7. The KELT-South Telescope

    E-Print Network [OSTI]

    Pepper, Joshua; Siverd, Robert; James, David; Stassun, Keivan

    2012-01-01

    The Kilodegree Extremely Little Telescope (KELT) project is a survey for new transiting planets around bright stars. KELT-South is a small-aperture, wide-field automated telescope located at Sutherland, South Africa. The telescope surveys a set of 26 degree by 26 degree fields around the southern sky, and targets stars in the range of 8 solar-type main-sequence stars.

  8. Wide Field Hard X-ray Survey Telescope: ProtoEXIST1

    E-Print Network [OSTI]

    J. Hong; J. E. Grindlay; N. Chammas; B. Allen; A. Copete; B. Said; M. Burke; J. Howell; T. Gauron; R. G. Baker; S. D. Barthelmy; S. Sheikh; N. Gehrels; W. R. Cook; J. A. Burnham; F. A. Harrison; J. Collins; S. Labov; A. Garson III; H. Krawczynski

    2007-09-17

    We report our progress on the development of pixellated imaging CZT detector arrays for our first-generation balloon-borne wide-field hard X-ray (20 - 600 keV) telescope, ProtoEXIST1. Our ProtoEXIST program is a pathfinder for the High Energy Telescope (HET) on the Energetic X-ray Imaging Survey telescope (EXIST), a proposed implementation of the Black Hole Finder Probe. ProtoEXIST1 consists of four independent coded-aperture telescopes with close-tiled (~0.4 mm gaps) CZT detectors that preserve their 2.5mm pixel pitch. Multiple shielding/field-of-view configurations are planned to identify optimal geometry for the HET in EXIST. The primary technical challenge in ProtoEXIST is the development of large area, close-tiled modules of imaging CZT detectors (1000 cm2 for ProtoEXIST1), with all readout and control systems for the ASIC readout vertically stacked. We describe the overall telescope configuration of ProtoEXIST1 and review the current development status of the CZT detectors, from individual detector crystal units (DCUs) to a full detector module (DM). We have built the first units of each component for the detector plane and have completed a few Rev2 DCUs (2x2 cm2), which are under a series of tests. Bare DCUs (pre-crystal bonding) show high, uniform ASIC yield (~70%) and ~30% reduction in electronics noise compared to the Rev1 equivalent. A Rev1 DCU already achieved ~1.2% FWHM at 662 keV, and preliminary analysis of the initial radiation tests on a Rev2 DCU shows ~ 4 keV FWHM at 60 keV (vs. 4.7 keV for Rev1). We therefore expect about <~1% FWHM at 662 keV with the Rev2 detectors.

  9. Large area graphene ion sensitive field effect transistors with tantalum pentoxide sensing layers for pH measurement at the Nernstian limit

    SciTech Connect (OSTI)

    Fakih, Ibrahim, E-mail: ibrahim.fakih@mail.mcgill.ca; Sabri, Shadi; Szkopek, Thomas, E-mail: thomas.szkopek@mcgill.ca [Department of Electrical and Computer Engineering, McGill University, Montreal, Quebec H3A 2A7 (Canada); Mahvash, Farzaneh [Department of Electrical and Computer Engineering, McGill University, Montreal, Quebec H3A 2A7 (Canada); Département de Chimie et Biochimie, Universite du Québec à Montréal, Montreal, Quebec H3C 3P8 (Canada); Nannini, Matthieu [McGill Nanotools Microfab, McGill University, Montreal, Quebec H3A 2A7 (Canada); Siaj, Mohamed [Département de Chimie et Biochimie, Universite du Québec à Montréal, Montreal, Quebec H3C 3P8 (Canada)

    2014-08-25

    We have fabricated and characterized large area graphene ion sensitive field effect transistors (ISFETs) with tantalum pentoxide sensing layers and demonstrated pH sensitivities approaching the Nernstian limit. Low temperature atomic layer deposition was used to deposit tantalum pentoxide atop large area graphene ISFETs. The charge neutrality point of graphene, inferred from quantum capacitance or channel conductance, was used to monitor surface potential in the presence of an electrolyte with varying pH. Bare graphene ISFETs exhibit negligible response, while graphene ISFETs with tantalum pentoxide sensing layers show increased sensitivity reaching up to 55?mV/pH over pH 3 through pH 8. Applying the Bergveld model, which accounts for site binding and a Guoy-Chapman-Stern picture of the surface-electrolyte interface, the increased pH sensitivity can be attributed to an increased buffer capacity reaching up to 10{sup 14} sites/cm{sup 2}. ISFET response was found to be stable to better than 0.05 pH units over the course of two weeks.

  10. Searches for large-scale anisotropy in the arrival directions of cosmic rays detected above energy of 10{sup 19} eV at the Pierre Auger observatory and the telescope array

    SciTech Connect (OSTI)

    Aab, A.; Abreu, P.; Andringa, S.; Aglietta, M.; Ahn, E. J.; Al Samarai, I.; Albuquerque, I. F. M.; Allekotte, I.; Asorey, H.; Allen, J.; Allison, P.; Almela, A.; Castillo, J. Alvarez; Alvarez-Muñiz, J.; Batista, R. Alves; Ambrosio, M.; Aramo, C.; Aminaei, A.; Anchordoqui, L.; Arqueros, F.; Collaboration: Pierre Auger Collaboration; Telescope Array Collaboration; and others

    2014-10-20

    Spherical harmonic moments are well-suited for capturing anisotropy at any scale in the flux of cosmic rays. An unambiguous measurement of the full set of spherical harmonic coefficients requires full-sky coverage. This can be achieved by combining data from observatories located in both the northern and southern hemispheres. To this end, a joint analysis using data recorded at the Telescope Array and the Pierre Auger Observatory above 10{sup 19} eV is presented in this work. The resulting multipolar expansion of the flux of cosmic rays allows us to perform a series of anisotropy searches, and in particular to report on the angular power spectrum of cosmic rays above 10{sup 19} eV. No significant deviation from isotropic expectations is found throughout the analyses performed. Upper limits on the amplitudes of the dipole and quadrupole moments are derived as a function of the direction in the sky, varying between 7% and 13% for the dipole and between 7% and 10% for a symmetric quadrupole.

  11. Searches for Large-Scale Anisotropy in the Arrival Directions of Cosmic Rays Detected above Energy of $10^{19}$ eV at the Pierre Auger Observatory and the Telescope Array

    SciTech Connect (OSTI)

    Aab, Alexander; et al,

    2014-10-07

    Spherical harmonic moments are well-suited for capturing anisotropy at any scale in the flux of cosmic rays. An unambiguous measurement of the full set of spherical harmonic coefficients requires full-sky coverage. This can be achieved by combining data from observatories located in both the northern and southern hemispheres. To this end, a joint analysis using data recorded at the Telescope Array and the Pierre Auger Observatory above 1019 eV is presented in this work. The resulting multipolar expansion of the flux of cosmic rays allows us to perform a series of anisotropy searches, and in particular to report on the angular power spectrum of cosmic rays above 1019 eV. No significant deviation from isotropic expectations is found throughout the analyses performed. Upper limits on the amplitudes of the dipole and quadrupole moments are derived as a function of the direction in the sky, varying between 7% and 13% for the dipole and between 7% and 10% for a symmetric quadrupole.

  12. OPENENDED CONFIGURATIONS OF RADIO TELESCOPES

    E-Print Network [OSTI]

    Kreinovich, Vladik

    telescopes, devices that use the second observability window of radio waves. #12; Why configurations of radioOPEN­ENDED CONFIGURATIONS OF RADIO TELESCOPES: TOWARDS OPTIMAL DESIGN VLADIK KREINOVICH, SCOTT A, Russia ABSTRACT The quality of radio astronomical images drastically depends on where we place the radio

  13. Space Telescope Programs Hubble Observatory

    E-Print Network [OSTI]

    Colorado at Boulder, University of

    Certifications required for all raw materials ­ Shelf Life (Polymerics) materials date controlled by QA · DesignsSpace Telescope Programs Hubble Observatory HST-COS FUV PER 11/8/00 FUV Detector System Materials;Space Telescope Programs Hubble Observatory HST-COS FUV PER 11/8/00 Materials and Processes · Materials

  14. Large-area triple-junction a-Si alloy production scaleup. Annual subcontract report, 17 March 1993--18 March 1994

    SciTech Connect (OSTI)

    Oswald, R.; Morris, J. [Solarex Corp., Newtown, PA (United States). Thin Film Div.

    1994-11-01

    The objective of this subcontract over its three-year duration is to advance Solarex`s photovoltaic manufacturing technologies, reduce its a-Si:H module production costs, increase module performance and expand the Solarex commercial production capacity. Solarex shall meet these objectives by improving the deposition and quality of the transparent front contact, by optimizing the laser patterning process, scaling-up the semiconductor deposition process, improving the back contact deposition, scaling-up and improving the encapsulation and testing of its a-Si:H modules. In the Phase 2 portion of this subcontract, Solarex focused on improving deposition of the front contact, investigating alternate feed stocks for the front contact, maximizing throughput and area utilization for all laser scribes, optimizing a-Si:H deposition equipment to achieve uniform deposition over large-areas, optimizing the triple-junction module fabrication process, evaluating the materials to deposit the rear contact, and optimizing the combination of isolation scribe and encapsulant to pass the wet high potential test. Progress is reported on the following: Front contact development; Laser scribe process development; Amorphous silicon based semiconductor deposition; Rear contact deposition process; Frit/bus/wire/frame; Materials handling; and Environmental test, yield and performance analysis.

  15. Cluster Observations with the South Pole Telescope

    E-Print Network [OSTI]

    Plagge, Thomas Jeffrey

    2009-01-01

    The South Pole Telescope during the last stages ofwater vapor at the South Pole relative to two otherSZ Survey Instrument . 3 The South Pole Telescope Observing

  16. Review of the Solar Array Telescopes

    E-Print Network [OSTI]

    David A. Smith

    2006-08-11

    For several years the only experiments sensitive to astrophysical gamma rays with energies beyond the reach of EGRET but below that of the Cherenkov imaging telescopes have been the "solar tower" detectors. They use >2000 m2 mirror areas to sample the Cherenkov wavefront generated by <100 GeV gamma rays, obtaining Crab sensitivities of more than 6$\\sigma$ in one ON-source hour. I will review the history of the solar tower Cherenkov experiments from 1992 to the present and their key design features. I will describe some successful analysis strategies, then summarize the principal results obtained.

  17. 3D acoustic imaging applied to the Baikal Neutrino Telescope

    E-Print Network [OSTI]

    K. G. Kebkal; R. Bannasch; O. G. Kebkal; A. I. Panfilov; R. Wischnewski

    2008-11-07

    A hydro-acoustic imaging system was tested in a pilot study on distant localization of elements of the Baikal underwater neutrino telescope. For this innovative approach, based on broad band acoustic echo signals and strictly avoiding any active acoustic elements on the telescope, the imaging system was temporarily installed just below the ice surface, while the telescope stayed in its standard position at 1100 m depth. The system comprised an antenna with four acoustic projectors positioned at the corners of a 50 meter square; acoustic pulses were "linear sweep-spread signals" - multiple-modulated wide-band signals (10-22 kHz) of 51.2 s duration. Three large objects (two string buoys and the central electronics module) were localized by the 3D acoustic imaging, with a accuracy of ~0.2 m (along the beam) and ~1.0 m (transverse). We discuss signal forms and parameters necessary for improved 3D acoustic imaging of the telescope, and suggest a layout of a possible stationary bottom based 3D imaging setup. The presented technique may be of interest for neutrino telescopes of km3-scale and beyond, as a flexible temporary or as a stationary tool to localize basic telescope elements, while these are completely passive.

  18. In-orbit performance of the XMM-Newton X-ray telescopes: images and spectra

    E-Print Network [OSTI]

    B. Aschenbach

    2001-09-21

    The performance of the three X-ray telescopes on-board of XMM-Newton is evaluated addressing imaging characteristics and effective collecting area. The agreement with ground calibration data is excellent. The analysis of images and spectra of cosmic X-ray sources, emphazising supernova and supernova remnants, prooves that the telescopes are even better than originally required.

  19. The Atacama Cosmology Telescope Project: A Progress Report

    E-Print Network [OSTI]

    Arthur Kosowsky; for the ACT Collaboration

    2006-08-25

    The Atacama Cosmology Telescope is a project to map the microwave background radiation at arcminute angular resolution and high sensitivity in three frequency bands over substantial sky areas. Cosmological signals driving such an experiment are reviewed, and current progress in hardware construction is summarized. Complementary astronomical observations in other wavebands are also discussed.

  20. Detection of ultra-high energy cosmic ray showers with a single-pixel fluorescence telescope

    E-Print Network [OSTI]

    Fujii, T; Bertaina, M; Casolino, M; Dawson, B; Horvath, P; Hrabovsky, M; Jiang, J; Mandat, D; Matalon, A; Matthews, J N; Motloch, P; Palatka, M; Pech, M; Privitera, P; Schovanek, P; Takizawa, Y; Thomas, S B; Travnicek, P; Yamazaki, K

    2015-01-01

    We present a concept for large-area, low-cost detection of ultra-high energy cosmic rays (UHECRs) with a Fluorescence detector Array of Single-pixel Tele- scopes (FAST), addressing the requirements for the next generation of UHECR experiments. In the FAST design, a large field of view is covered by a few pixels at the focal plane of a mirror or Fresnel lens. We report first results of a FAST prototype installed at the Telescope Array site, consisting of a single 200 mm photomultiplier tube at the focal plane of a 1 m2 Fresnel lens system taken from the prototype of the JEM-EUSO experiment. The FAST prototype took data for 19 nights, demonstrating remarkable operational stability. We detected laser shots at distances of several kilometres as well as 16 highly significant UHECR shower candidates.

  1. Flasher and muon-based calibration of the GCT telescopes proposed for the Cherenkov Telescope Array

    E-Print Network [OSTI]

    Brown, Anthony M; Chadwick, Paula M; Daniel, Michael; White, Richard

    2015-01-01

    The GCT is a dual-mirror Small-Sized-Telescope prototype proposed for the Cherenkov Telescope Array. Calibration of the GCT's camera is primarily achieved with LED-based flasher units capable of producing $\\sim4$ ns FWHM pulses of 400 nm light across a large dynamic range, from 0.1 up to 1000 photoelectrons. The flasher units are housed in the four corners of the camera's focal plane and illuminate it via reflection from the secondary mirror. These flasher units are adaptable to allow several calibration scenarios to be accomplished: camera flat-fielding, linearity measurements (up to and past saturation), and gain estimates from both single pe measurements and from the photon statistics at various high illumination levels. In these proceedings, the performance of the GCT flashers is described, together with ongoing simulation work to quantify the efficiency of using muon rings as an end-to-end calibration for the optical throughput of the GCT.

  2. The Thermal Control of the New Solar Telescope at Big Bear Observatory

    E-Print Network [OSTI]

    For large-diameter solar telescopes operating at the theoretical diffraction limit, one of the main designThe Thermal Control of the New Solar Telescope at Big Bear Observatory Angelo P. Verdonia and Carsten Denkera aNew Jersey Institute of Technology, Center for Solar-Terrestrial Research, 323 Martin

  3. Wind tunnel testing of a generic telescope enclosure Tait S. Pottebaum*a

    E-Print Network [OSTI]

    MacMynowski, Douglas G. - MacMynowski, Douglas G.

    -buffeting, wind tunnel, DPIV 1. INTRODUCTION Various design studies are currently underway for the next generation that CFD can be used with confidence in future design work. Keywords: Extremely-Large-Telescopes, Wind with confidence in future design work. For an 80m diameter telescope dome in a 12m/s external wind (roughly the 85

  4. Parametric modeling and control of telescope wind-induced vibration

    E-Print Network [OSTI]

    MacMynowski, Douglas G. - MacMynowski, Douglas G.

    -buffeting is presented. The model is being developed to support the design of next generation segmented-mirror optical: Parametric modeling, extremely large telescope, control, wind-buffeting 1. INTRODUCTION Various design the predictions of the former at one or more points in the design space. An initial parametric model of wind

  5. An Optical Reflector System for the CANGAROO-II Telescope

    E-Print Network [OSTI]

    Akiko Kawachi

    1999-11-30

    We have developed light and durable mirrors made of CFRP (Carbon Fiber Reinforced Plastics) laminates for the reflector of the new CANGAROO-II 7 m telescope. The reflector has a parabolic shape (F/1.1) with a 30 m^2 effective area which consists of 60 small spherical mirrors. The attitude of each mirror can be remotely adjusted by stepping motors. After the first adjustment work, the re ector offers a point image of about 0.14 degree (FWHM) on the optic axis. The telescope has been in operation since May 1999 with an energy threshold of ~ 300 GeV.

  6. An Optical Reflector System for the CANGAROO-II Telescope

    E-Print Network [OSTI]

    Kawachi, A

    1999-01-01

    We have developed light and durable mirrors made of CFRP (Carbon Fiber Reinforced Plastics) laminates for the reflector of the new CANGAROO-II 7 m telescope. The reflector has a parabolic shape (F/1.1) with a 30 m^2 effective area which consists of 60 small spherical mirrors. The attitude of each mirror can be remotely adjusted by stepping motors. After the first adjustment work, the re ector offers a point image of about 0.14 degree (FWHM) on the optic axis. The telescope has been in operation since May 1999 with an energy threshold of ~ 300 GeV.

  7. Wide field of view telescope

    DOE Patents [OSTI]

    Ackermann, Mark R. (Albuquerque, NM); McGraw, John T. (Placitas, NM); Zimmer, Peter C. (Albuquerque, NM)

    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.

  8. Relay telescope for high power laser alignment system

    DOE Patents [OSTI]

    Dane, C. Brent; Hackel, Lloyd; Harris, Fritz B.

    2006-09-19

    A laser system includes an optical path having an intracavity relay telescope with a telescope focal point for imaging an output of the gain medium between an image location at or near the gain medium and an image location at or near an output coupler for the laser system. A kinematic mount is provided within a vacuum chamber, and adapted to secure beam baffles near the telescope focal point. An access port on the vacuum chamber is adapted for allowing insertion and removal of the beam baffles. A first baffle formed using an alignment pinhole aperture is used during alignment of the laser system. A second tapered baffle replaces the alignment aperture during operation and acts as a far-field baffle in which off angle beams strike the baffle a grazing angle of incidence, reducing fluence levels at the impact areas.

  9. Neutrino telescopes in the World

    SciTech Connect (OSTI)

    Ernenwein, J.-P.

    2007-01-12

    Neutrino astronomy has rapidly developed these last years, being the only way to get specific and reliable information about astrophysical objects still poorly understood.Currently two neutrino telescopes are operational in the World: BAIKAL, in the lake of the same name in Siberia, and AMANDA, in the ices of the South Pole. Two telescopes of the same type are under construction in the Mediterranean Sea: ANTARES and NESTOR. All these telescopes belong to a first generation, with an instrumented volume smaller or equal to 0.02 km3. Also in the Mediterranean Sea, the NEMO project is just in its stag phase, within the framework of a cubic kilometer size neutrino telescope study. Lastly, the ICECUBE detector, with a volume reaching about 1 km3, is under construction on the site of AMANDA experiment, while an extension of the BAIKAL detector toward km3 is under study. We will present here the characteristics of these experiments, as well as the results of their observations.

  10. The Large Observatory For X-ray Timing: LOFT

    E-Print Network [OSTI]

    Bozzo, E

    2013-01-01

    LOFT, the Large Observatory for X-ray Timing, is a new space mission concept devoted to observations of Galactic and extra-Galactic sources in the X-ray domain with the main goals of probing gravity theory in the very strong field environment of black holes and other compact objects, and investigating the state of matter at supra-nuclear densities in neutron stars. The instruments on-board LOFT, the Large area detector and the Wide Field Monitor combine for the first time an unprecedented large effective area (~10 m2 at 8 keV) sensitive to X-ray photons mainly in the 2-30 keV energy range and a spectral resolution approaching that of CCD-based telescopes (down to 200 eV at 6 keV). LOFT is currently competing for a launch of opportunity in 2022 together with the other M3 mission candidates of the ESA Cosmic Vision Program.

  11. Minimizing actuator-induced residual error in active space telescope primary mirrors

    E-Print Network [OSTI]

    Smith, Matthew William, Ph. D. Massachusetts Institute of Technology

    2010-01-01

    Heritage space telescope mirror technology-i.e. large, monolithic glass primary mirrors-has reached an upper limit on allowable aperture diameter given launch vehicle volume and mass constraints. The next generation of ...

  12. Exo-zodi modelling for the Large Binocular Telescope Interferometer

    E-Print Network [OSTI]

    Kennedy, Grant M.; Wyatt, Mark C.; Bailey, Vanessa; Bryden, Geoffrey; Danchi, William C.; Defrère, Denis; Haniff, Philip M.; Lebreton, Jérémy; Mennesson, Bertrand; Millan-Gabet, Rafael; Morales, Farisa; Pani?, Olja; Rieke, George H.; Roberge, Aki; Serabyn, Eugene; Shannon, Andrew; Skemer, Andrew J.; Stapelfeldt, Karl R.; Su, Katherine Y. L.; Weinberger, Alycia J.

    2015-01-27

    on the Mid-Infrared Instrument (MIRI) on the 4 Unless the dust has a very high albedo (?0.9), non-detection with high quality mid-IR photometry is already sufficient to restrict this dust to lie well inside the habitable zone (Kennedy et al., in prep). 8 G. M... as the LBTI. Such photometry will provide the most useful constraints on the disk location, so we now briefly outline how the total and LBTI-transmitted disk fluxes vary with model parameters, in particular the disk inner and outer radii. To illustrate...

  13. Business opportunities Developing the European Extremely Large Telescope

    E-Print Network [OSTI]

    partnerships with other companies, and create strong opportunities for product innovation given the high are a challenging mix of innovative developments which push the boundaries of engineering, including the creation ­ the primary mirror alone will be made of 798 segment pieces. The innovation arising from this work to develop

  14. Optical Design for Extremely Large Telescope Adaptive Optics...

    Office of Scientific and Technical Information (OSTI)

    these analyses, important conclusions about configurations are derived. PWFS's, which offer an alternative to Shack-Hartmann (SH) wavefront sensors (WFS's), are envisioned as the...

  15. Transit timing with fast cameras on large telescopes

    E-Print Network [OSTI]

    Adams, Elisabeth Rose

    2010-01-01

    Timing and system parameters were measured for seven transiting exoplanets: OGLETR- 56b (11 transits), OGLE-TR-132b (7), OGLE-TR-111b (6), OGLE-TR-113b (6), CoRoT-2b (3), OGLE-TR-10b (3), and XO-2b (2). Ground-based ...

  16. Optical Design for Extremely Large Telescope Adaptive Optics Systems

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech ConnectSpeeding access to science

  17. Optical Design for Extremely Large Telescope Adaptive Optics Systems

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech ConnectSpeeding access to science(Thesis/Dissertation) | SciTech Connect

  18. High resolution telescope including an array of elemental telescopes aligned along a common axis and supported on a space frame with a pivot at its geometric center

    DOE Patents [OSTI]

    Norbert, M.A.; Yale, O.

    1992-04-28

    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 employes 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 a 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 activities. The cost of the telescope scales with the first power of the aperture rather than its third power as in conventional telescopes. 15 figs.

  19. High resolution telescope including an array of elemental telescopes aligned along a common axis and supported on a space frame with a pivot at its geometric center

    DOE Patents [OSTI]

    Norbert, Massie A. (San Ramon, CA); Yale, Oster (Danville, CA)

    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 employes 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 a 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 activities. The cost of the telescope scales with the first power of the aperture rather than its third power as in conventional telescopes.

  20. The high resolution silicon telescope of the INSULAB group

    E-Print Network [OSTI]

    Bonfanti, Silvia; Lietti, Daniela; Vallazza, Erik

    This thesis has focused on the study of the performance of the high resolution tracking system (telescope) of the INSULAB group and on the implementation of a new data acquisition (DAQ) to comply with the high rate of the CERN North Area extracted beams. This system has allowed to increase the DAQ rate by a factor two with respect to the “standard” electronics. The INSULAB telescope is designed to test detectors ranging from calorimeters to more complex systems like in the case of the bent crystals studied by the COHERENT experiment. The telescope consists of four 300 $mu$m thick double side silicon strip detector modules with an area of 1.92$\times$1.92 cm$^{2}$ and 384 strips. The readout pitch is 50 $mu$m on both sides of the module but the junction side has an implant pitch of 25 $mu$m (and thus a floating strip) to improve the resolution. The telescope has been installed on the H4 beamline at the CERN SPS for the commissioning of the new readout system in June 2012. The results are analyzed in terms...

  1. OPEN-ENDED CONFIGURATIONS OF RADIO TELESCOPES

    E-Print Network [OSTI]

    Kreinovich, Vladik

    radio telescopes, devices that use the second observability window of radio waves. Why configurationsOPEN-ENDED CONFIGURATIONS OF RADIO TELESCOPES: A GEOMETRICAL ANALYSIS Vladik Kreinovich, Scott A. The quality of radio astronomical images drastically depends on where we place the radio telescopes. During

  2. Liquid Mirror Telescopes: A progress report

    E-Print Network [OSTI]

    Ermanno F. Borra; Marc Ferrari; Luc Girard; Gilberto Moretto; Gregoire Tremblay; Gerard Lemaitre

    1996-08-23

    We review the present status of liquid mirror telescopes. Interferometric tests of liquid mirrors (the largest one having a diameter of 2.5 meters ) show excellent optical qualities. The basic technology is now sufficiently reliable that it can be put to work. Indeed, a handful of liquid mirrors have now been built that are used for scientific work. A 3.7-m diameter LMT is presently being built in the new Laval upgraded testing facilities. Construction of the mirror can be followed on the Web site: http://astrosun.phy.ulaval.ca/lmt/lmt- home.html. Finally we address the issue of the field accessible to LMTs equipped with novel optical correctors. Optical design work, and some exploratory laboratory work, indicate that a single LMT should be able to access, with excellent images, small regions anywhere inside fields as large as 45 degrees.

  3. Area Telescope Weltevrede, P.; /Australia, CSIRO, Epping /Manchester...

    Office of Scientific and Technical Information (OSTI)

    U. IASF, Milan Milan Polytechnic DAPNIA, Saclay INFN, Perugia Perugia U. NASA, Goddard NASA, Goddard CSST, Baltimore Stanford U., HEPL KIPAC, Menlo Park...

  4. Square Kilometer Array Telescope - Precision Reference Frequency Synchronisation via 1f-2f Dissemination

    E-Print Network [OSTI]

    Wang, B; Gao, C; Bai, Y; Dong, J W; Wang, L J

    2015-01-01

    The Square Kilometer Array (SKA) is an international effort to build the world's largest radio telescope, with one square kilometer collecting area. Besides its ambitious scientific objectives, such as probing the cosmic dawn and cradle of life, SKA also demands several revolutionary technological breakthroughs, with ultra-high precision synchronisation of the frequency references for thousands of antennas being one of them. In this report, aimed at applications to SKA, we demonstrate a frequency reference synchronization and dissemination scheme with the phase noise compensation function placed at the client site. Hence, one central hub can be linked to a large number of client sites, forming a star-shaped topology. As a performance test, the 100 MHz reference signal from a Hydrogen maser clock is disseminated and recovered at two remote sites. Phase noise characteristics of the recovered reference frequency signal coincides with that of the hydrogen-maser source and satisfies SKA requirement.

  5. E x c e l l e n c e w i t h I m p a c t -P a r t o f R e s e a r c h C o u n c i l s U K The European Extremely Large Telescope

    E-Print Network [OSTI]

    telescope systems and developing manufacturing processes for the optical elements. In addition £150 million order for manufacturing the production segments in UK industry. Companies already addressing grand challenges Additional economic benefits will accrue from capability-building in industry

  6. The Standing Wave Phenomenon in Radio Telescopes; Frequency Modulation of the WSRT Primary Beam

    E-Print Network [OSTI]

    Attila Popping; Robert Braun

    2007-12-14

    Inadequacies in the knowledge of the primary beam response of current interferometric arrays often form a limitation to the image fidelity. We hope to overcome these limitations by constructing a frequency-resolved, full-polarization empirical model for the primary beam of the Westerbork Synthesis Radio Telescope (WSRT). Holographic observations, sampling angular scales between about 5 arcmin and 11 degrees, were obtained of a bright compact source (3C147). These permitted measurement of voltage response patterns for seven of the fourteen telescopes in the array and allowed calculation of the mean cross-correlated power beam. Good sampling of the main-lobe, near-in, and far-side-lobes out to a radius of more than 5 degrees was obtained. A robust empirical beam model was detemined in all polarization products and at frequencies between 1322 and 1457 MHz with 1 MHz resolution. Substantial departures from axi-symmetry are apparent in the main-lobe as well as systematic differences between the polarization properties. Surprisingly, many beam properties are modulated at the 5 to 10% level with changing frequency. These include: (1) the main beam area, (2) the side-lobe to main-lobe power ratio, and (3) the effective telescope aperture. These semi-sinusoidsal modulations have a basic period of about 17 MHz, consistent with the natural 'standing wave' period of a 8.75 m focal distance. The deduced frequency modulations of the beam pattern were verified in an independent long duration observation using compact continuum sources at very large off-axis distances. Application of our frequency-resolved beam model should enable higher dynamic range and improved image fidelity for interferometric observations in complex fields. (abridged)

  7. Parallel waveform extraction algorithms for the Cherenkov Telescope Array Real-Time Analysis

    E-Print Network [OSTI]

    Zoli, Andrea; De Rosa, Adriano; Aboudan, Alessio; Fioretti, Valentina; De Cesare, Giovanni; Marx, Ramin

    2015-01-01

    The Cherenkov Telescope Array (CTA) is the next generation observatory for the study of very high-energy gamma rays from about 20 GeV up to 300 TeV. Thanks to the large effective area and field of view, the CTA observatory will be characterized by an unprecedented sensitivity to transient flaring gamma-ray phenomena compared to both current ground (e.g. MAGIC, VERITAS, H.E.S.S.) and space (e.g. Fermi) gamma-ray telescopes. In order to trigger the astrophysics community for follow-up observations, or being able to quickly respond to external science alerts, a fast analysis pipeline is crucial. This will be accomplished by means of a Real-Time Analysis (RTA) pipeline, a fast and automated science alert trigger system, becoming a key system of the CTA observatory. Among the CTA design key requirements to the RTA system, the most challenging is the generation of alerts within 30 seconds from the last acquired event, while obtaining a flux sensitivity not worse than the one of the final analysis by more than a fac...

  8. The Advanced Compton Telescope Mission

    E-Print Network [OSTI]

    Steven E. Boggs; James Kurfess; James Ryan; Elena Aprile; Neil Gehrels; Marc Kippen; Mark Leising; Uwe Oberlack; Cornelia Wunderer; Allen Zych; Peter Bloser; Michael Harris; Andrew Hoover; Alexei Klimenk; Dan Kocevski; Mark McConnell; Peter Milne; Elena I. Novikova; Bernard Phlips; Mark Polsen; Steven Sturner; Derek Tournear; Georg Weidenspointner; Eric Wulf; Andreas Zoglauer; Matthew Baring; John Beacom; Lars Bildsten; Charles Dermer; Dieter Hartmann; Margarita Hernanz; David Smith; Sumner Starrfield; for the larger ACT collaboration

    2006-08-24

    The Advanced Compton Telescope (ACT), the next major step in gamma-ray astronomy, will probe the fires where chemical elements are formed by enabling high-resolution spectroscopy of nuclear emission from supernova explosions. During the past two years, our collaboration has been undertaking a NASA mission concept study for ACT. This study was designed to (1) transform the key scientific objectives into specific instrument requirements, (2) to identify the most promising technologies to meet those requirements, and (3) to design a viable mission concept for this instrument. We present the results of this study, including scientific goals and expected performance, mission design, and technology recommendations.

  9. Abstract--We have recently completed a large-area, coded-aperture, gamma-ray imager for use in searching for radiation

    E-Print Network [OSTI]

    Horn, Berthold K.P.

    - strument [2] that makes a map of the radiation field as it trav- erses a region. The pixel size of the map in searching for radiation sources. The instrument was constructed to verify that weak point sources can sufficient radiation can reach a large gamma-ray detec- tor from a small source to make detection possible

  10. Electronic Transmission and Computation of Very Long Baseline Interferometry and Its Application to Next Generation Radio Telescopes

    E-Print Network [OSTI]

    Melbourne, University of

    @atnf.csiro.au Abstract Australia is contributing to the next generation radio telescope, the Square Kilometre Array (SKA processors. 1. Introduction The Square Kilometre Array (SKA) is a next- generation radio telescope planned for operation around 2015. As the name implies, it will encompass a square kilometre of collecting area

  11. A Hubble Space Telescope Survey of X-ray Luminous Galaxy Clusters: Gravitationally Lensed Arcs and EROs

    E-Print Network [OSTI]

    Graham P. Smith

    2002-01-15

    We are conducting a systematic lensing survey of X-ray luminous galaxy clusters at z~0.2 using the Hubble Space Telescope and large ground-based telescopes. We summarize initial results from our survey, including a measurement of the inner slope of the mass profile of A383, and a search for gravitationally lensed Extremely Red Objects.

  12. Wide-Field InfrarRed Survey Telescope-Astrophysics Focused Telescope Assets WFIRST-AFTA 2015 Report

    E-Print Network [OSTI]

    Spergel, D; Baltay, C; Bennett, D; Breckinridge, J; Donahue, M; Dressler, A; Gaudi, B S; Greene, T; Guyon, O; Hirata, C; Kalirai, J; Kasdin, N J; Macintosh, B; Moos, W; Perlmutter, S; Postman, M; Rauscher, B; Rhodes, J; Wang, Y; Weinberg, D; Benford, D; Hudson, M; Jeong, W -S; Mellier, Y; Traub, W; Yamada, T; Capak, P; Colbert, J; Masters, D; Penny, M; Savransky, D; Sterns, D; Zimmerman, N; Barry, R; Bartusek, L; Carpenter, K; Cheng, E; Content, D; Dekens, F; Demers, R; Grady, K; Jackson, C; Kuan, G; Kruk, J; Melton, M; Nemati, B; Parvin, B; Poberezhskiy, I; Peddie, C; Ruffa, J; Wallace, J K; Whipple, A; Wollack, E; Zhao, F

    2015-01-01

    This report describes the 2014 study by the Science Definition Team (SDT) of the Wide-Field Infrared Survey Telescope (WFIRST) mission. It is a space observatory that will addresses the most compelling scientific problems in dark energy, exoplanets and general astrophysics using a 2.4m telescope with a wide-field infrared instrument and an optical coronagraph. The Astro2010 Decadal Survey recommended a Wide Field Infrared Survey Telescope as its top priority for a new large space mission. As conceived by the decadal survey, WFIRST would carry out a dark energy science program, a microlensing program to determine the demographics of exoplanets, and a general observing program utilizing its ultra wide field. In October 2012, NASA chartered a Science Definition Team (SDT) to produce, in collaboration with the WFIRST Study Office at GSFC and the Program Office at JPL, a Design Reference Mission (DRM) for an implementation of WFIRST using one of the 2.4-m, Hubble-quality telescope assemblies recently made availabl...

  13. SETI reloaded, Next Generation Radio Telescopes, Transients and Cognitive Computing

    E-Print Network [OSTI]

    Garrett, Michael A

    2015-01-01

    The Search for Extra-terrestrial Intelligence (SETI) using radio telescopes is an area of research that is now more than 50 years old. Thus far, both targeted and wide-area surveys have yet to detect artificial signals from intelligent civilisations. In this paper, I argue that the incidence of co-existing intelligent and communicating civilisations is probably small in the Milky Way. While this makes successful SETI searches a very difficult pursuit indeed, the huge impact of even a single detection requires us to continue the search. A substantial increase in the overall performance of radio telescopes (and in particular future wide-field instruments such as the Square Kilometre Array, SKA), provide renewed optimism in the field. Evidence for this is already to be seen in the success of SETI researchers in acquiring observations on some of the world's most sensitive radio telescope facilities via open, peer-reviewed processes. The increasing interest in the dynamic radio sky, and our ability to detect new a...

  14. Recent Results from Telescope Array

    E-Print Network [OSTI]

    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.

  15. The reflecting surface of the MAGIC-II Telescope

    E-Print Network [OSTI]

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

    2007-09-10

    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.

  16. First images on the sky from a hyper telescope

    E-Print Network [OSTI]

    E. Pedretti; A. Labeyrie; L. Arnold; N. Thureau; O. Lardiere; A. Boccaletti; P. Riaud

    2000-09-28

    We show star images obtained with a miniature ``densified pupil imaging interferometer'' also called a hyper-telescope. The formation of such images violates a ``golden rule of imaging interferometers'' which appeared to forbid the use of interferometric arrangements differing from a Fizeau interferometer. These produce useless images when the sub-apertures spacing is much wider than their size, owing to diffraction through the sub-apertures. The hyper-telescope arrangement solves these problems opening the way towards multi-kilometer imaging arrays in space. We experimentally obtain an intensity gain of 24 +- 3X when a densified-pupil interferometer is compared to an equivalent Fizeau-type interferometer and show images of the double star alpha Gem. The initial results presented confirm the possibility of directly obtaining high resolution and high dynamic range images in the recombined focal plane of a large interferometer if enough elements are used.

  17. Cross Calibration of Telescope Optical Throughput Efficiencies using Reconstructed Shower Energies for the Cherenkov Telescope Array

    E-Print Network [OSTI]

    Mitchell, A M W; Hofmann, W; Bernloehr, K

    2015-01-01

    For reliable event reconstruction of Imaging Atmospheric Cherenkov Telescopes (IACTs), calibration of the optical throughput efficiency is required. Within current facilities, this is achieved through the use of ring shaped images generated by muons. Here, a complementary approach is explored, achieving cross calibration of elements of IACT arrays through pairwise comparisons between telescopes, focussing on its applicability to the upcoming Cherenkov Telescope Array (CTA). Intercalibration of telescopes of a particular type using eventwise comparisons of shower image amplitudes has previously been demonstrated to recover the relative telescope optical responses. A method utilising the reconstructed energy as an alternative to image amplitude is presented, enabling cross calibration between telescopes of varying types within an IACT array. Monte Carlo studies for two plausible CTA layouts have shown that this calibration procedure recovers the relative telescope response efficiencies at the few percent level.

  18. Astron. Nachr. / AN 331, No. 6, 636 639 (2010) / DOI 10.1002/asna.201011390 Scientific instrumentation for the 1.6 m New Solar Telescope in Big Bear

    E-Print Network [OSTI]

    2010-01-01

    structures drive us to build large-aperture solar telescopes and state-of-the-art facility- class instruments come for building meters-class solar telescopes. New Jersey Institute of Technology (NJIT), in collab instrumentation for the 1.6 m New Solar Telescope in Big Bear W. Cao1,2, , N. Gorceix2 , R. Coulter2 , K. Ahn3 , T

  19. James Webb Space Telescope: PM Lessons Applied - Eric Smith,...

    Energy Savers [EERE]

    James Webb Space Telescope: PM Lessons Applied - Eric Smith, Deputy Program Director, NASA James Webb Space Telescope: PM Lessons Applied - Eric Smith, Deputy Program Director,...

  20. "Thinking" Telescopes: An Autonomous Robotic Ecosystem for Persistent...

    Office of Scientific and Technical Information (OSTI)

    "Thinking" Telescopes: An Autonomous Robotic Ecosystem for Persistent Monitoring and Real-Time Response Citation Details In-Document Search Title: "Thinking" Telescopes: An...

  1. The Nuclear Spectroscopic Telescope Array (NuSTAR) Mission (Journal...

    Office of Scientific and Technical Information (OSTI)

    The Nuclear Spectroscopic Telescope Array (NuSTAR) Mission Citation Details In-Document Search Title: The Nuclear Spectroscopic Telescope Array (NuSTAR) Mission You are...

  2. The Nuclear Spectroscopic Telescope Array (NuSTAR) Mission (Journal...

    Office of Scientific and Technical Information (OSTI)

    The Nuclear Spectroscopic Telescope Array (NuSTAR) Mission Citation Details In-Document Search Title: The Nuclear Spectroscopic Telescope Array (NuSTAR) Mission Authors: Harrison,...

  3. The Nuclear Spectroscopic Telescope Array (NuSTAR) Mission (Journal...

    Office of Scientific and Technical Information (OSTI)

    Nuclear Spectroscopic Telescope Array (NuSTAR) Mission Citation Details In-Document Search Title: The Nuclear Spectroscopic Telescope Array (NuSTAR) Mission Authors: Harrison,...

  4. An Optical Reflector for the CANGAROO-II Telescope

    E-Print Network [OSTI]

    Kawachi, A; Dazeley, S A; Edwards, P G; Gunji, S; Hara, S; Hara, T; Jinbo, J; Kifune, T; Kubo, H; Matsubara, Y; Mizumoto, Y; Mori, M; Moriya, M; Muraishi, H; Muraki, Y; Naito, T; Nishijima, K; Patterson, J R; Roberts, M D; Rowell, G P; Sako, T; Sakurazawa, K; Sato, Y; Susukita, R; Tamura, T; Tanimori, T; Yanagita, S; Yoshida, T; Yoshikoshi, T; Yuki, A; Kawachi, Akiko

    1999-01-01

    We have been successful in developing light and durable mirrors made of CFRP (Carbon Fiber Reinforced Plastic) laminates for the reflector of the new CANGAROO-II 7 m telescope. The reflector has a parabolic shape (F/1.1) with a 30 m^2 effective area which consists of 60 small spherical mirrors of CFRP laminates. The orientation of each mirror can be remotely adjusted by stepping motors. After the first adjustment work, the reflector offers a point image of about $0.^\\circ 14$ (FWHM) on the optic axis.

  5. An Optical Reflector for the CANGAROO-II Telescope

    E-Print Network [OSTI]

    Akiko Kawachi; J. Kushida; S. A. Dazeley; S. A. Dazeley; P. G. Edwards; S. Gunji; S. Hara; T. Hara; J. Jinbo; T. Kifune; H. Kubo; Y. Matsubara; Y. Mizumoto; M. Mori; M. Moriya; H. Muraishi; Y. Muraki; T. Naito; K. Nishijima; J. R. Patterson; M. D. Roberts; G. P. Rowell; T. Sako; K. Sakurazawa; Y. Sato; R. Susukita; T. Tamura; T. Tanimori; S. Yanagita; T. Yoshida; T. Yoshikoshi; A. Yuki

    1999-06-04

    We have been successful in developing light and durable mirrors made of CFRP (Carbon Fiber Reinforced Plastic) laminates for the reflector of the new CANGAROO-II 7 m telescope. The reflector has a parabolic shape (F/1.1) with a 30 m^2 effective area which consists of 60 small spherical mirrors of CFRP laminates. The orientation of each mirror can be remotely adjusted by stepping motors. After the first adjustment work, the reflector offers a point image of about $0.^\\circ 14$ (FWHM) on the optic axis.

  6. CCD drift-scan imaging lunar occultations: a feasible approach for sub-meter class telescopes

    E-Print Network [OSTI]

    O. Fors; J. Nunez; A. Richichi

    2001-08-27

    A CCD drift-scanning technique for lunar occultation (LO) observations is presented. While this approach has been addressed before by Sturmann (1994) for the case of large telescopes, the technical validity has never been discussed for sub-meter class telescopes. In contrast to Sturmann's scheme, the proposed technique places the CCD in the image plane of the telescope. This does not represent a problem in the case of small telescopes, where the practical angular resolution attainable by LO is not limited by aperture smoothing. Photon-generated charge is read out at millisecond rate on a column-per-column basis, as the diffraction pattern of the occulted star is being tracked. Two LO events (SAO 79031 and SAO 77911) were observed to demonstrate the feasibility of the method. Data analysis was carried out and no angular diameter the observed stars were resolved. We show, however, that the technique could be useful for close binary detections with small telescopes. A discussion of the limiting resolution and magnitude imposed by our instrumentation is carried out, showing that drift-scanning technique could be extended to 1-2m telescopes for stellar diameter determination purposes. Finally, we point out that the technical demands required by this technique can be easily met by most small professional observatories and advanced amateurs.

  7. Construction of a medium-sized Schwarzschild-Couder telescope as a candidate for the Cherenkov Telescope Array: development of the optical alignment system

    E-Print Network [OSTI]

    Nieto, D; Humensky, B; Kaaret, P; Limon, M; Mognet, I; Peck, A; Petrashyk, A; Ribeiro, D; Rousselle, J; Stevenson, B; Vassiliev, V; Yu, P

    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. The Schwarzschild-Couder (SC) medium-size candidate telescope model features a novel aplanatic two-mirror optical design capable of a wide field-of-view with significantly improved imaging resolution as compared to the traditional Davis-Cotton optics design. Achieving this imaging resolution imposes strict alignment requirements to be accomplished by a dedicated alignment system. In this contribution we present the status of the development of the SC optical alignment system, soon to be materialized in a full-scale prototype SC medium-size telescope at the Fred Lawrence Whipple Observatory in southern ...

  8. Facility class Rayleigh beacon AO system for the 4.2m William Herschel Telescope

    E-Print Network [OSTI]

    R. G. M. Rutten; P. Clark; R. M. Myers; R. W. Wilson; R. G. Bingham; E. Emsellem; T. Gregory; R. A. Humphreys; J. H. Knapen; G. Moretto; S. L. Morris; G. Talbot

    2002-08-07

    A rationale is presented for the use of a relatively low-altitude Rayleigh Laser Guide Star to provide partial adaptive optics correction across a large fraction of the sky on the 4.2m William Herschel Telescope. The scientific motivation is highlighted and supported by model calculations. An overview the technical implementation of the system is presented.

  9. Wind Loads on Ground-Based Telescopes Douglas G. MacMynowskia*

    E-Print Network [OSTI]

    MacMynowski, Douglas G. - MacMynowski, Douglas G.

    distribution of wind disturbances are defined as a function of relevant design parameters, providing Introduction Design studies are underway for the next generation of large ground-based optical telescopes still lead to significant vibration1,2 . Estimates of the wind loads are required early in the design

  10. THE ARMAGH-DUNSINK-HARVARD TELESCOPE: FROM DREAM TO OBLIVION C. J. BUTLER

    E-Print Network [OSTI]

    and they made important contributions to the emerging disciplines of cosmology, solar physics and stellar recognised achievements was his part in the setting up of a large Schmidt telescope, the ADH, in South Africa, nebulosity's - gosh!" At last, the project could move forward, now with the newly reopened Dunsink

  11. Telescopic nanotube device for hot nanolithography

    DOE Patents [OSTI]

    Popescu, Adrian; Woods, Lilia M

    2014-12-30

    A device for maintaining a constant tip-surface distance for producing nanolithography patterns on a surface using a telescopic nanotube for hot nanolithography. An outer nanotube is attached to an AFM cantilever opposite a support end. An inner nanotube is telescopically disposed within the outer nanotube. The tip of the inner nanotube is heated to a sufficiently high temperature and brought in the vicinity of the surface. Heat is transmitted to the surface for thermal imprinting. Because the inner tube moves telescopically along the outer nanotube axis, a tip-surface distance is maintained constant due to the vdW force interaction, which in turn eliminates the need of an active feedback loop.

  12. Accurate Telescope Mount Positioning with MEMS Accelerometers

    E-Print Network [OSTI]

    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.

  13. Extreme multiplex spectroscopy at wide-field 4-m telescopes

    E-Print Network [OSTI]

    Robert Content; Tom Shanks

    2008-08-18

    We describe the design and science case for a spectrograph for the prime focus of classical 4-m wide-field telescopes that can deliver at least 4000 MOS slits over a 1 degree field. This extreme multiplex capability means that 25000 galaxy redshifts can be measured in a single night, opening up the possibilities for large galaxy redshift surveys out to z~0.7 and beyond for the purpose of measuring the Baryon Acoustic Oscillation (BAO) scale and for many other science goals. The design features four cloned spectrographs and exploits the exclusive possibility of tiling the focal plane of wide-field 4-m telescopes with CCDs for multi-object spectroscopic purposes. In ~200 night projects, such spectrographs have the potential to make galaxy redshift surveys of ~6 million galaxies over a wide redshift range and thus may provide a low-cost alternative to other survey routes such as WFMOS and SKA. Two of these extreme multiplex spectrographs are currently being designed for the AAT (NG1dF) and Calar Alto (XMS) 4-m class telescopes. NG2dF, a larger version for the AAT 2 degree field, would have 12 clones and at least 12000 slits. The clones use a transparent design including a grism in which all optics are smaller than the clone square subfield so that the clones can be tightly packed with little gaps between the contiguous fields. Only low cost glasses are used; the variations in chromatic aberrations between bands are compensated by changing one or two of the lenses adjacent to the grism. The total weight and length is smaller with a few clones than a unique spectrograph which makes it feasible to place the spectrograph at the prime focus.

  14. Prototype of the SST-1M Telescope Structure for the Cherenkov Telescope Array

    E-Print Network [OSTI]

    Niemiec, J; B?ocki, J; Bogacz, L; Borkowski, J; Bulik, T; Cadoux, F; Christov, A; Cury?o, M; della Volpe, D; Dyrda, M; Favre, Y; Frankowski, A; Grudnik, ?; Grudzi?ska, M; Heller, M; Id?kowski, B; Jamrozy, M; Janiak, M; Kasperek, J; Lalik, K; Lyard, E; Mach, E; Mandat, D; Marsza?ek, A; Micha?owski, J; Moderski, R; Montaruli, T; Neronov, A; Ostrowski, M; Pa?ko, P; Pech, M; Porcelli, A; Prandini, E; Rajda, P; Rameez, M; Schioppa, E jr; Schovanek, P; Seweryn, K; Skowron, K; Sliusar, V; Sowi?ski, M; Stawarz, ?; Stodulska, M; Stodulski, M; Pujadas, I Troyano; Toscano, S; Walter, R; Wi?cek, M; Zagda?ski, A; Zi?tara, 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.

  15. Relay telescope including baffle, and high power laser amplifier utilizing the same

    DOE Patents [OSTI]

    Dane, C. Brent; Hackel, Lloyd; Harris, Fritz B.

    2006-09-19

    A laser system includes an optical path having an intracavity relay telescope with a telescope focal point for imaging an output of the gain medium between an image location at or near the gain medium and an image location at or near an output coupler for the laser system. A kinematic mount is provided within a vacuum chamber, and adapted to secure beam baffles near the telescope focal point. An access port on the vacuum chamber is adapted for allowing insertion and removal of the beam baffles. A first baffle formed using an alignment pinhole aperture is used during alignment of the laser system. A second tapered baffle replaces the alignment aperture during operation and acts as a far-field baffle in which off angle beams strike the baffle a grazing angle of incidence, reducing fluence levels at the impact areas.

  16. Creating a high-resolution picture of Cygnus with the Cherenkov Telescope Array

    E-Print Network [OSTI]

    Weinstein, Amanda; Casanova, Sabrina; Di Girolamo, Tristano; Dyrda, Michael; Hahn, Joachim; Majumdar, Pratik; Rodriguez, Jerome; Tibaldo, Luigi

    2015-01-01

    The Cygnus region hosts one of the most remarkable star-forming regions in the Milky Way. Indeed, the total mass in molecular gas of the Cygnus X complex exceeds 10 times the total mass of all other nearby star-forming regions. Surveys at all wavelengths, from radio to gamma-rays, reveal that Cygnus contains such a wealth and variety of sources---supernova remnants (SNRs), pulsars, pulsar wind nebulae (PWNe), H II regions, Wolf-Rayet binaries, OB associations, microquasars, dense molecular clouds and superbubbles---as to practically be a galaxy in microcosm. The gamma-ray observations along reveal a wealth of intriguing sources at energies between 1 GeV and tens of TeV. However, a complete understanding of the physical phenomena producing this gamma-ray emission first requires us to disentangle overlapping sources and reconcile discordant pictures at different energies. This task is made more challenging by the limited angular resolution of instruments such as the Fermi Large Area Telescope, ARGO-YBJ, and HAW...

  17. Optical Technology Needs for Future Space Telescopes

    E-Print Network [OSTI]

    Van Stryland, Eric

    , Visible, Near-IR, Far-IR, Sub-MM, Microwave, Radio Wave, Gravity Waves, etc. See Advanced Telescope / Spectroscopy (Vis-IR-FIR) Multi-Spectral Sensing (UV-Gamma) Laser / LIDAR Remote Sensing Microwave Instruments Structure #12;NASA's Science Missions Directorate Themes: Earth Science Sun-Solar System Connection Solar

  18. Dutch Open Telescope Virtual Solar Observatory

    E-Print Network [OSTI]

    Rutten, Rob

    telescope building. The DOT is open and is mounted on a 15 m high open tower to exploit the superior atmospheric seeing at La Palma brought by the oceanic trade wind. The clamshell bad-weather canopy is folded to feed the solar physics research by the small DOT group at Utrecht, but very much underexploits

  19. A High Speed Networked Signal Processing Platform for Multi-element Radio Telescopes

    E-Print Network [OSTI]

    Prasad, Peeyush; 10.1007/s10686-011-9216-7

    2011-01-01

    A new architecture is presented for a Networked Signal Processing System (NSPS) suitable for handling the real-time signal processing of multi-element radio telescopes. In this system, a multi-element radio telescope is viewed as an application of a multi-sensor, data fusion problem which can be decomposed into a general set of computing and network components for which a practical and scalable architecture is enabled by current technology. The need for such a system arose in the context of an ongoing program for reconfiguring the Ooty Radio Telescope (ORT) as a programmable 264-element array, which will enable several new observing capabilities for large scale surveys on this mature telescope. For this application, it is necessary to manage, route and combine large volumes of data whose real-time collation requires large I/O bandwidths to be sustained. Since these are general requirements of many multi-sensor fusion applications, we first describe the basic architecture of the NSPS in terms of a Fusion Tree ...

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

    E-Print Network [OSTI]

    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.

  1. The Jay Baum Rich telescope: a Centurion 28 at the Wise Observatory

    E-Print Network [OSTI]

    Brosch, Noah; Niv, Saar; Manulis, Ilan

    2015-01-01

    We describe the third telescope of the Wise Observatory, a 0.70-m Centurion 28 (C28IL) installed in 2013 and named the Jay Baum Rich telescope to enhance significantly the wide-field imaging possibilities of the observatory. The telescope operates from a 5.5-m diameter dome and is equipped with a large-format red-sensitive CCD camera, offering a ~one square degree imaged field sampled at 0".83/pixel. The telescope was acquired to provide an alternative to the existing 1-m telescope for studies such as microlensing, photometry of transiting exo-planets, the follow-up of supernovae and other optical transients, and the detection of very low surface brightness extended features around galaxies. The operation of the C28IL is robotic, requiring only the creation of a night observing plan that is loaded in the afternoon prior to the observations. The entire facility was erected for a component and infrastructure cost of well under 300k$ and a labor investment of about two person-year. The successful implementation ...

  2. Photometric Calibration of the Swift Ultraviolet/Optical Telescope

    E-Print Network [OSTI]

    Poole, T S; Page, M J; Landsman, W; Holland, S T; Roming, P; Kuin, N P M; Brown, P J; Gronwall, C; Hunsberger, S; Koch, S; Mason, K O; Schady, P; Berk, D Vanden; Blustin, A J; Boyd, P; Broos, P; Carter, M; Chester, M M; Cucchiara, A; Hancock, B; Huckle, H; Immler, S; Ivanushkina, M; Kennedy, T; Marshall, F; Morgan, A; Pandey, S; de Pasquale, M; Smith, P J; Still, M

    2007-01-01

    We present the photometric calibration of the Swift UltraViolet/Optical Telescope (UVOT) which includes: optimum photometric and background apertures, effective area curves, colour transformations, conversion factors for count rates to flux, and the photometric zero points (which are accurate to better than 4 per cent) for each of the seven UVOT broadband filters. The calibration was performed with observations of standard stars and standard star fields that represent a wide range of spectral star types. The calibration results include the position dependent uniformity, and instrument response over the 1600-8000A operational range. Because the UVOT is a photon counting instrument, we also discuss the effect of coincidence loss on the calibration results. We provide practical guidelines for using the calibration in UVOT data analysis. The results presented here supersede previous calibration results.

  3. Photometric Calibration of the Swift Ultraviolet/Optical Telescope

    E-Print Network [OSTI]

    T. S. Poole; A. A. Breeveld; M. J. Page; W. Landsman; S. T. Holland; P. Roming; N. P. M. Kuin; P. J. Brown; C. Gronwall; S. Hunsberger; S. Koch; K. O. Mason; P. Schady; D. Vanden Berk; A. J. Blustin; P. Boyd; P. Broos; M. Carter; M. M. Chester; A. Cucchiara; B. Hancock; H. Huckle; S. Immler; M. Ivanushkina; T. Kennedy; F. Marshall; A. Morgan; S. Pandey; M. de Pasquale; P. J. Smith; M. Still

    2007-11-09

    We present the photometric calibration of the Swift UltraViolet/Optical Telescope (UVOT) which includes: optimum photometric and background apertures, effective area curves, colour transformations, conversion factors for count rates to flux, and the photometric zero points (which are accurate to better than 4 per cent) for each of the seven UVOT broadband filters. The calibration was performed with observations of standard stars and standard star fields that represent a wide range of spectral star types. The calibration results include the position dependent uniformity, and instrument response over the 1600-8000A operational range. Because the UVOT is a photon counting instrument, we also discuss the effect of coincidence loss on the calibration results. We provide practical guidelines for using the calibration in UVOT data analysis. The results presented here supersede previous calibration results.

  4. The New Hampshire Astronomical Society Library Telescope Program

    E-Print Network [OSTI]

    The New Hampshire Astronomical Society Library Telescope Program The NHAS's Library Telescope are borrowed. Over the past three years NHAS has placed telescopes in nearly 30 New Hampshire libraries is a clinical social worker in private practice. Some may even recognize him as New Hampshire's most favorite

  5. Hubble Space Telescope characterized by using phase-retrieval algorithms

    E-Print Network [OSTI]

    Fienup, James R.

    of the optical axis of a camera relay telescope relative to the main telescope. After we accounted for measured spherical aberration in the relay telescope,our estimate of the conicconstant of the primary mirror ofthe with the results of a blind test that was distributed to several groups. Section 4 describes some of the parameters

  6. AUTOMATIC GUIDING OF THE PRIMARY IMAGE OF SOLAR GREGORY TELESCOPES

    E-Print Network [OSTI]

    AUTOMATIC GUIDING OF THE PRIMARY IMAGE OF SOLAR GREGORY TELESCOPES G. KÜVELER1, E. WIEHR2, D of solar Gregory telescopes is used for automatic guiding. This new system avoids temporal varying at the Gregory telescopes at Tenerife and at Locarno, is described. 1. Introduction Automatic guiding

  7. Paper II: Calibration of the Swift ultraviolet/optical telescope

    E-Print Network [OSTI]

    Breeveld, A A; Hoversten, E A; Koch, S; Landsman, W; Marshall, F E; Page, M J; Poole, T S; Roming, P; Smith, P J; Still, M; Yershov, V; Blustin, A J; Brown, P J; Gronwall, C; Holland, S T; Kuin, N P M; McGowan, K; Rosen, S; Boyd, P; Broos, P; Carter, M; Chester, M M; Hancock, B; Huckle, H; Immler, S; Ivanushkina, M; Kennedy, T; Mason, K O; Morgan, A N; Oates, S; de Pasquale, M; Schady, P; Siegel, M; Berk, D Vanden

    2010-01-01

    The Ultraviolet/Optical Telescope (UVOT) is one of three instruments onboard the Swift observatory. The photometric calibration has been published, and this paper follows up with details on other aspects of the calibration including a measurement of the point spread function with an assessment of the orbital variation and the effect on photometry. A correction for large scale variations in sensitivity over the field of view is described, as well as a model of the coincidence loss which is used to assess the coincidence correction in extended regions. We have provided a correction for the detector distortion and measured the resulting internal astrometric accuracy of the UVOT, also giving the absolute accuracy with respect to the International Celestial Reference System. We have compiled statistics on the background count rates, and discuss the sources of the background, including instrumental scattered light. In each case we describe any impact on UVOT measurements, whether any correction is applied in the st...

  8. The Automated Palomar 60-Inch Telescope

    E-Print Network [OSTI]

    S. Bradley Cenko; Derek B. Fox; Dae-Sik Moon; Fiona A. Harrison; S. R. Kulkarni; John R. Henning; C. Dani Guzman; Marco Bonati; Roger M. Smith; Robert P. Thicksten; Michael W. Doyle; Hal L. Petrie; Avishay Gal-Yam; Alicia M. Soderberg; Nathaniel L. Anagnostou; Anastasia C. Laity

    2006-08-15

    We have converted the Palomar 60-inch telescope (P60) from a classical night assistant-operated telescope to a fully robotic facility. The automated system, which has been operational since September 2004, is designed for moderately fast (t <~ 3 minutes) and sustained (R <~ 23 mag) observations of gamma-ray burst afterglows and other transient events. Routine queue-scheduled observations can be interrupted in response to electronic notification of transient events. An automated pipeline reduces data in real-time, which is then stored on a searchable web-based archive for ease of distribution. We describe here the design requirements, hardware and software upgrades, and lessons learned from roboticization. We present an overview of the current system performance as well as plans for future upgrades.

  9. Status and Plans for the Array Control and Data Acquisition System of the Cherenkov Telescope Array

    E-Print Network [OSTI]

    Oya, I; Schwanke, U; Wegner, P; Balzer, A; Berge, D; Borkowski, J; Camprecios, J; Colonges, S; Colome, J; Champion, C; Conforti, V; Gianotti, F; Flour, T Le; Lindemann, R; Lyard, E; Mayer, M; Melkumyan, D; Punch, M; Tanci, C; Schmidt, T; Schwarz, J; Tosti, G; Verma, K; Weinstein, A; Wiesand, S; Wischnewski, R

    2015-01-01

    The Cherenkov Telescope Array (CTA) is the next-generation atmospheric Cherenkov gamma-ray observatory. CTA will consist of two installations, one in the northern, and the other in the southern hemisphere, containing tens of telescopes of different sizes. The CTA performance requirements and the inherent complexity associated with the operation, control and monitoring of such a large distributed multi-telescope array leads to new challenges in the field of the gamma-ray astronomy. The ACTL (array control and data acquisition) system will consist of the hardware and software that is necessary to control and monitor the CTA arrays, as well as to time-stamp, read-out, filter and store -at aggregated rates of few GB/s- the scientific data. The ACTL system must be flexible enough to permit the simultaneous automatic operation of multiple sub-arrays of telescopes with a minimum personnel effort on site. One of the challenges of the system is to provide a reliable integration of the control of a large and heterogene...

  10. Telescoping magnetic ball bar test gage

    DOE Patents [OSTI]

    Bryan, J.B.

    1982-03-15

    A telescoping magnetic ball bar test gage for determining the accuracy of machine tools, including robots, and those measuring machines having non-disengagable servo drives which cannot be clutched out. Two gage balls are held and separated from one another by a telescoping fixture which allows them relative radial motional freedom but not relative lateral motional freedom. The telescoping fixture comprises a parallel reed flexure unit and a rigid member. One gage ball is secured by a magnetic socket knuckle assembly which fixes its center with respect to the machine being tested. The other gage ball is secured by another magnetic socket knuckle assembly which is engaged or held by the machine in such manner that the center of that ball is directed to execute a prescribed trajectory, all points of which are equidistant from the center of the fixed gage ball. As the moving ball executes its trajectory, changes in the radial distance between the centers of the two balls caused by inaccuracies in the machine are determined or measured by a linear variable differential transformer (LVDT) assembly actuated by the parallel reed flexure unit. Measurements can be quickly and easily taken for multiple trajectories about several different fixed ball locations, thereby determining the accuracy of the machine.

  11. The Small and Moderate Aperture Research Telescope System A Proposal to Operate the Small Telescopes at CTIO

    E-Print Network [OSTI]

    Walter, Frederick M.

    The Small and Moderate Aperture Research Telescope System (SMARTS) A Proposal to Operate the Small Observatory #12; The Small and Moderate Aperture Research Telescope System (SMARTS) ABSTRACT We propose to operate four telescopes located at the Cerro Tololo Interamerican Observatory (CTIO) for the period from

  12. ANTARES deep sea neutrino telescope results

    SciTech Connect (OSTI)

    Mangano, Salvatore [IFIC - Instituto de Física Corpuscular, Edificio Institutos de Investigatión, 46071 Valencia (Spain); Collaboration: ANTARES Collaboration

    2014-01-01

    The ANTARES experiment is currently the largest underwater neutrino telescope in the Northern Hemisphere. It is taking high quality data since 2007. Its main scientific goal is to search for high energy neutrinos that are expected from the acceleration of cosmic rays from astrophysical sources. This contribution reviews the status of the detector and presents several analyses carried out on atmospheric muons and neutrinos. For example it shows the results from the measurement of atmospheric muon neutrino spectrum and of atmospheric neutrino oscillation parameters as well as searches for neutrinos from steady cosmic point-like sources, for neutrinos from gamma ray bursts and for relativistic magnetic monopoles.

  13. The Microchannel X-ray Telescope on Board the SVOM Satellite

    E-Print Network [OSTI]

    Gotz, D; Basa, S; Beckmann, V; Burwitz, V; Chipaux, R; Cordier, B; Evans, P; Godet, O; Goosmann, R; Meidinger, N; Meuris, A; Motch, C; Nandra, K; O'Brien, P; Osborne, J; Perinati, E; Rau, A; Willingale, R; Mercier, K; Gonzalez, F

    2015-01-01

    We present the Micro-channel X-ray Telescope (MXT), a new narrow-field (about 1{\\deg}) telescope that will be flying on the Sino-French SVOM mission dedicated to Gamma-Ray Burst science, scheduled for launch in 2021. MXT is based on square micro pore optics (MPOs), coupled with a low noise CCD. The optics are based on a "Lobster Eye" design, while the CCD is a focal plane detector similar to the type developed for the seven eROSITA telescopes. MXT is a compact and light (<35 kg) telescope with a 1 m focal length, and it will provide an effective area of about 45 cmsq on axis at 1 keV. The MXT PSF is expected to be better than 4.2 arc min (FWHM) ensuring a localization accuracy of the afterglows of the SVOM GRBs to better than 1 arc min (90\\% c.l. with no systematics) provided MXT data are collected within 5 minutes after the trigger. The MXT sensitivity will be adequate to detect the afterglows for almost all the SVOM GRBs as well as to perform observations of non-GRB astrophysical objects. These performan...

  14. Crystal diffraction lens telescope for focusing nuclear gamma rays

    SciTech Connect (OSTI)

    Smither, R.K.; Fernandez, P.B.; Graber, T. [Argonne National Lab., IL (United States). Advanced Photon Source; Ballmoos, P. von; Naya, J.; Albernhe, F.; Vedrenne, G. [Centre d`Etude Spatiale des Rayonnements, Toulouse (France); Faiz, M. [KFUPM, Dhahran (Saudi Arabia). Physics Dept.

    1996-08-01

    A crystal diffraction lens was constructed at Argonne National Laboratory for use as a telescope to focus nuclear gamma rays. It consisted of 600 single crystals of germanium arranged in 8 concentric rings. The mounted angle of each crystal was adjusted to intercept and diffract the incoming gamma rays with an accuracy of a few arc sec. The performance of the lens was tested in two ways. In one case, the gamma rays were focused on a single medium size germanium detector. In the second case, the gamma rays were focused on the central germanium detector of a 3 x 3 matrix of small germanium detectors. The efficiency, image concentration and image quality, and shape were measured. The tests performed with the 3 x 3 matrix detector system were particularly interesting. The wanted radiation was concentrated in the central detector. The 8 other detectors were used to detect the Compton scattered radiation, and their energy was summed with coincident events in the central detector. This resulted in a detector with the efficiency of a large detector (all 9 elements) and the background of a small detector (only the central element). The use of the 3 x 3 detector matrix makes it possible to tell if the source is off axis and, if so, to tell in which direction. The crystal lens acts very much like a simple convex lens for visible light. Thus if the source is off to the left then the image will focus off to the right illuminating the detector on the right side: telling one in which direction to point the telescope. Possible applications of this type of crystal lens to balloon and satellite experiments will be discussed.

  15. A facility to evaluate the focusing performance of mirrors for Cherenkov Telescopes

    E-Print Network [OSTI]

    Canestrari, Rodolfo; Bonnoli, Giacomo; Farisato, Giancarlo; Lessio, Luigi; Rodeghiero, Gabriele; Spiga, Rossella; Toso, Giorgio; Pareschi, Giovanni

    2015-01-01

    With the advent of the imaging atmospheric Cherenkov technique in late 1980's, ground-based observations of Very High-Energy gamma rays came into reality. Since the first source detected at TeV energies in 1989 by Whipple, the number of high energy gamma-ray sources has rapidly grown up to more than 150 thanks to the second generation experiments like MAGIC, H.E.S.S. and VERITAS. The Cherenkov Telescope Array observatory is the next generation of Imaging Atmospheric Cherenkov Telescopes, with at least 10 times higher sensitivity than current instruments. Cherenkov Telescopes have to be equipped with optical dishes of large diameter -- in general based on segmented mirrors -- with typical angular resolution of a few arc-minutes. To evaluate the mirror's quality specific metrological systems are required that possibly take into account the environmental conditions in which typically Cherenkov telescopes operate (in open air without dome protection). For this purpose a new facility for the characterization of mi...

  16. The X-ray Telescope of CAST

    E-Print Network [OSTI]

    M. Kuster; H. Bräuninger; S. Cébrian; M. Davenport; C. Elefteriadis; J. Englhauser; H. Fischer; J. Franz; P. Friedrich; R. Hartmann; F. H. Heinsius; D. H. H. Hoffmann; G. Hoffmeister; J. N. Joux; D. Kang; K. Königsmann; R. Kotthaus; T. Papaevangelou; C. Lasseur; A. Lippitsch; G. Lutz; J. Morales; A. Rodríguez; L. Strüder; J. Vogel; K. Zioutas

    2007-05-10

    The Cern Axion Solar Telescope (CAST) is in operation and taking data since 2003. The main objective of the CAST experiment is to search for a hypothetical pseudoscalar boson, the axion, which might be produced in the core of the sun. The basic physics process CAST is based on is the time inverted Primakoff effect, by which an axion can be converted into a detectable photon in an external electromagnetic field. The resulting X-ray photons are expected to be thermally distributed between 1 and 7 keV. The most sensitive detector system of CAST is a pn-CCD detector combined with a Wolter I type X-ray mirror system. With the X-ray telescope of CAST a background reduction of more than 2 orders off magnitude is achieved, such that for the first time the axion photon coupling constant g_agg can be probed beyond the best astrophysical constraints g_agg < 1 x 10^-10 GeV^-1.

  17. Beam calibration of radio telescopes with drones

    E-Print Network [OSTI]

    Chang, Chihway; Refregier, Alexandre; Amara, Adam; Glauser, Adrian; Casura, Sarah

    2015-01-01

    We present a multi-frequency far-field beam map for the 5m dish telescope at the Bleien Observatory measured using a commercially available drone. We describe the hexacopter drone used in this experiment, the design of the flight pattern, and the data analysis scheme. This is the first application of this calibration method to a single dish radio telescope in the far-field. The high signal-to-noise data allows us to characterise the beam pattern with high accuracy out to at least the 4th side-lobe. The resulting 2D beam pattern is compared with that derived from a more traditional calibration approach using an astronomical calibration source. We discuss the advantages of this method compared to other beam calibration methods. Our results show that this drone-based technique is very promising for ongoing and future radio experiments, where the knowledge of the beam pattern is key to obtaining high-accuracy cosmological and astronomical measurements.

  18. The University of Durham Mark 6 VHE gamma ray telescope

    SciTech Connect (OSTI)

    Chadwick, P. M.; Dickinson, M. R.; Dipper, N. A.; Holder, J.; Kendall, T. R.; McComb, T. J. L.; Orford, K. J.; Rayner, S. M.; Roberts, I. D.; Shaw, S. E.; Turver, K. E.

    1997-05-10

    The operation of the University of Durham Mark 6 atmospheric Cerenkov telescope is discussed. The telescope has been used to detect gamma rays at energies {>=}150 GeV and to achieve good discrimination between gamma ray and hadron initiated showers, using both conventional imaging and novel fluctuation measures. The telescope was commissioned in 1995 and a description of its operation is presented. Verification of the performance during observations of PSR B1706-44 is described.

  19. A generation of astronomical telescopes, their users, and publications

    E-Print Network [OSTI]

    Trimble, V

    2010-01-01

    optical telescopes. Publications of the Astronomical Society737. Abt, H. A. (2009). Publications of the Astronomicaltelescopes, their users, and publications Table 3 Papers and

  20. SIMULATION STUDY OF BACKGROUND PARTICLES IN THE MUON TELESCOPE...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    SIMULATION STUDY OF BACKGROUND PARTICLES IN THE MUON TELESCOPE DETECTOR AT THE STAR EXPERIMENT Matthew Breen Thanks to Dr. Mioduszewski and Yanfang Liu Overview Background ...

  1. The Atacama Cosmology Telescope: Cosmology from Galaxy Clusters...

    Office of Scientific and Technical Information (OSTI)

    The Atacama Cosmology Telescope: Cosmology from Galaxy Clusters Detected via the Sunyaev-Zel'dovich Effect Citation Details In-Document Search Title: The Atacama Cosmology...

  2. The AMiBA Hexapod Telescope Mount

    E-Print Network [OSTI]

    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.

  3. Using SPICA Space Telescope to characterize Exoplanets

    E-Print Network [OSTI]

    J. R. Goicoechea; B. Swinyard; G. Tinetti; T. Nakagawa; K. Enya; M. Tamura; M. Ferlet; K. G. Isaak; M. Wyatt; A. D. Aylward; M. Barlow; J. P. Beaulieu; A. Boccaletti; J. Cernicharo; J. Cho; R. Claudi; H. Jones; H. Lammer; A. Leger; J. Martín-Pintado; S. Miller; F. Najarro; D. Pinfield; J. Schneider; F. Selsis; D. M. Stam; J. Tennyson; S. Viti; G. White

    2008-09-15

    We present the 3.5m SPICA space telescope, a proposed Japanese-led JAXA-ESA mission scheduled for launch around 2017. The actively cooled ( 18 um). SPICA is one of the few space missions selected to go to the next stage of ESA's Cosmic Vision 2015-2025 selection process. In this White Paper we present the main specifications of the three instruments currently baselined for SPICA: a mid-infrared (MIR) coronagraph (~3.5 to ~27 um) with photometric and spectral capabilities (R~200), a MIR wide-field camera and high resolution spectrometer (R~30,000), and a far-infrared (FIR ~30 to ~210 um) imaging spectrometer - SAFARI - led by a European consortium. We discuss their capabilities in the context of MIR direct observations of exo-planets (EPs) and multiband photometry/high resolution spectroscopy observations of transiting exo-planets. We conclude that SPICA will be able to characterize the atmospheres of transiting exo-planets down to the super-Earth size previously detected by ground- or space-based observatories. It will also directly detect and characterize Jupiter/Neptune-size planets orbiting at larger separation from their parent star (>5-10 AU), by performing quantitative atmospheric spectroscopy and studying proto-planetary and debris disks. In addition, SPICA will be a scientific and technological precursor for future, more ambitious, IR space missions for exo-planet direct detection as it will, for example, quantify the prevalence exo-zodiacal clouds in planetary systems and test coronographic techniques, cryogenic systems and lightweight, high quality telescopes. (abridged)

  4. Imaging Fourier transform spectroscopy with multi-aperture telescopes

    E-Print Network [OSTI]

    Fienup, James R.

    Imaging Fourier transform spectroscopy with multi-aperture telescopes Samuel T. Thurman and James R Hanover St., Palo Alto, CA 94304 Abstract: Fourier spectroscopy can be performed with multi Society of America OCIS codes: (300.6300) Spectroscopy, Fourier transforms; (110.6770) Telescopes; (120

  5. Representations and image classification methods for Cherenkov telescopes

    SciTech Connect (OSTI)

    Malagon, C.; Parcerisa, D. S.; Barrio, J. A.; Nieto, D.

    2008-05-29

    The problem of identifying gamma ray events out of charged cosmic ray background (so called hadrons) in Cherenkov telescopes is one of the key problems in VHE gamma ray astronomy. In this contribution, we present a novel approach to this problem by implementing different classifiers relying on the information of each pixel of the camera of a Cherenkov telescope.

  6. VERITAS The Very Energetic Radiation Imaging Telescope Array System

    E-Print Network [OSTI]

    Weekes, T C; Biller, S D; Breslin, A C; Buckley, J H; Carter-Lewis, D A; Catanese, M; Cawley, M F; Dingus, B L; Fazio, G G; Fegan, D J; Finley, J; Fishman, G; Gaidos, J A; Gillanders, G H; Gorham, P W; Grindlay, J E; Hillas, A M; Huchra, J P; Kaaret, P E; Kertzman, M P; Kieda, D B; Krennrich, F; Lamb, R C; Lang, M J; Marscher, A P; Matz, S; McKay, T; Müller, D; Ong, R; Purcell, W; Rose, J; Sembroski, G H; Seward, F D; Slane, P O; Swordy, S P; Tümer, T O; Ulmer, M P; Urban, M; Wilkes, B J

    1997-01-01

    A next generation atmospheric Cherenkov observatory is described based on the Whipple Observatory $\\gamma$-ray telescope. A total of nine such imaging telescopes will be deployed in an array that will permit the maximum versatility and give high sensitivity in the 50 GeV - 50 TeV band (with maximum sensitivity from 100 GeV to 10 TeV).

  7. Rapid GRB Followup with the 2m Robotic Liverpool Telescope

    E-Print Network [OSTI]

    Gomboc, Andreja

    Rapid GRB Follow­up with the 2­m Robotic Liverpool Telescope Andreja Gomboc #,+ , Michael F. Bode. We present the capabilities of the 2­m robotic Liverpool Telescope (LT), owned and operated by Liverpool John Moores University and situated at ORM, La Palma. Robotic control and scheduling of the LT

  8. Collecting Light with Telescopes Two Fundamentally Different Spectral Mechanisms

    E-Print Network [OSTI]

    Shirley, Yancy

    ;Observing problems due to Earth's atmosphere 1. Light Pollution #12;Star viewed with ground-based telescope. · Location/technology can help overcome light pollution and turbulence. · Nothing short of going to space canCollecting Light with Telescopes #12;Two Fundamentally Different Spectral Mechanisms Spectral lines

  9. Adaptive Optics at the Subaru Telescope: current capabilities and development

    E-Print Network [OSTI]

    Guyon, Olivier

    Adaptive Optics at the Subaru Telescope: current capabilities and development Olivier Guyona Barbara, CA 93106, USA ABSTRACT Adaptive optics is a key component of Subaru Telescope's current-limited images in near-IR. In its LGS mode, laser light is transported from the solid state laser to the launch

  10. A Prototype for the Cherenkov Telescope Array Pipelines Framework: Modular Efficiency Simple System (MESS)

    E-Print Network [OSTI]

    ,

    2015-01-01

    The Cherenkov Telescope Array (CTA) is a ground-based $\\gamma$-ray observatory that will observe the full sky in the energy range from 20 GeV to 100 TeV from facilities in both hemispheres. It is proposed to consist of more than 100 telescopes, producing large amounts of data. Apart from the storage system, there are also requirements on the software framework to allow efficient data processing, i.e. robustness, execution speed and coding efficiency. This contribution will present a plain and simple pipeline framework design prototype for CTA that builds upon well-known tools, allowing the users to focus on physics problems without learning complicated software paradigms.

  11. Liverpool Telescope 2: a new robotic facility for time domain astronomy in 2020+

    E-Print Network [OSTI]

    Copperwheat, C M; Bates, S D; Smith, R J; Bode, M F; Baker, I; Peacocke, T; Thomson, K

    2014-01-01

    The robotic 2m Liverpool Telescope, based on the Canary island of La Palma, has a diverse instrument suite and a strong track record in time domain science, with highlights including early time photometry and spectra of supernovae, measurements of the polarization of gamma-ray burst afterglows, and high cadence light curves of transiting extrasolar planets. In the next decade the time domain will become an increasingly prominent part of the astronomical agenda with new facilities such as LSST, SKA, CTA and Gaia, and promised detections of astrophysical gravitational wave and neutrino sources opening new windows on the transient universe. To capitalise on this exciting new era we intend to build Liverpool Telescope 2: a new robotic facility on La Palma dedicated to time domain science. The next generation of survey facilities will discover large numbers of new transient sources, but there will be a pressing need for follow-up observations for scientific exploitation, in particular spectroscopic follow-up. Live...

  12. PONDER - A Real time software backend for pulsar and IPS observations at the Ooty Radio Telescope

    E-Print Network [OSTI]

    Naidu, Arun; Manoharan, P K; Krishnakumar, M A

    2015-01-01

    This paper describes a new real-time versatile backend, the Pulsar Ooty Radio Telescope New Digital Efficient Receiver (PONDER), which has been designed to operate along with the legacy analog system of the Ooty Radio Telescope (ORT). PONDER makes use of the current state of the art computing hardware, a Graphical Processing Unit (GPU) and sufficiently large disk storage to support high time resolution real-time data of pulsar observations, obtained by coherent dedispersion over a bandpass of 16 MHz. Four different modes for pulsar observations are implemented in PONDER to provide standard reduced data products, such as time-stamped integrated profiles and dedispersed time series, allowing faster avenues to scientific results for a variety of pulsar studies. Additionally, PONDER also supports general modes of interplanetary scintillation (IPS) measurements and very long baseline interferometry data recording. The IPS mode yields a single polarisation correlated time series of solar wind scintillation over a b...

  13. Design of a telescope pointing and tracking subsystem for the Big Bear Solar Observatory New Solar Telescope

    E-Print Network [OSTI]

    Design of a telescope pointing and tracking subsystem for the Big Bear Solar Observatory New Solar Telescope J. R. Varsika and G.Yangb aBig Bear Solar Observatory, 40386 North Shore Lane, Big Bear City, California, U.S.A.; bNew Jersey Institute of Technology, Newark, New Jersey, U.S.A. ABSTRACT The New Solar

  14. Performance of the Mechanical Structure of the SST-2M GCT Proposed for the Cherenkov Telescope Array

    E-Print Network [OSTI]

    Dournaux, Jean-Laurent; Dumas, Delphine; Amans, Jean-Philippe; Fasola, Gilles; Laporte, Philippe; Bousquet, Jean-Jacques; Sol, Hélène

    2015-01-01

    The Cherenkov Telescope Array (CTA) consortium aims to create the next generation Very High Energy gamma-ray observatory. It will be devoted to the observation of gamma rays over a wide band of energy, from 20 GeV to 300 TeV. Three different classes, Large, Medium and Small Size Telescopes, are foreseen to cover the low, intermediate and high energy regions, respectively. The energy range of the Small Size Telescopes (SSTs) extends from 1 TeV to 300 TeV. Among them, the Gamma-ray Cherenkov Telescope (GCT), a telescope based on a Schwarzschild-Couder dual-mirror optical design, is one of the prototypes under construction proposed for the SST sub-array of CTA. This contribution focuses on the mechanical structure of GCT. It reports on last progress on the mechanical design and discusses this in the context of CTA specifications. Recent advances in the assembly and installation of the opto-mechanical prototype of GCT on the French site of the Paris Observatory are also described.

  15. Research Areas

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDid youOxygen Generation |Publications TheGashome /Areas Research Areas

  16. The Gemini 8M Telescopes Project M. Mountain, F. Gillett, R. Kurz

    E-Print Network [OSTI]

    The Gemini 8­M Telescopes Project M. Mountain, F. Gillett, R. Kurz Gemini Telescopes Project, 950 N. Cherry Ave., Tucson AZ 85719 Gemini Preprint # 5 #12; The Gemini 8­M Telescopes Project Matt Mountain

  17. Real-time condition assessment of RAPTOR telescope systems

    SciTech Connect (OSTI)

    Stull, Chris; Taylor, Stuart; Wren, James; Farrar, Charles; Park, Gyuhae

    2010-11-30

    The RAPid Telescopes for Optical Response (RAPTOR) observatory network consists of several robotic astronomical telescopes primarily designed to search for astrophysical transients called a gamma-ray bursts (GRBs). Although intrinsically bright, GRBs are difficult to detect because of their short duration. Typically, they are first observed by satellites that then relay the coordinates of the GRB to a ground station which, in turn, distributes the coordinates over the internet so that ground based observers can perform follow-up observations. Typically the ground based observations begin after the GRB has ended and only residual emiSSion (the 'afterglow') is left. However, if the satellite relays the GRB coordinates quickly enough, a 'fast' robotic telescope on the ground may be able to catch the GRB in progress. The RAPTOR telescope system is one of only a few in the world to have accomplished this feat. In order to achieve these results, the RAPTOR telescopes must operate autonomously at a high duty-cycle and in peak operating condition. Currently the telescopes are maintained in an ad hoc manner, often in a run-to-failure mode. The RAPTOR project could benefit greatly from a structural health monitoring (SHM) system, especially as more complex units are added to the suite of telescopes. This paper will summarize preliminary results from an SHM study performed on one of the RAPTOR telescopes. Damage scenarios that are of concern and that have been previously observed are first summarized. Then a specific study of damage to the telescope drive mechanism is presented where the data acquisition system is first described. Next, damage detection algorithms are developed with LANL's new publically available software SHMTools and the results of this process are discussed in detail. The paper will conclude with a summary of future planned refinemenls of the RAPTOR SHM system.

  18. Developments of a new mirror technology for the Cherenkov Telescope Array

    E-Print Network [OSTI]

    ,

    2015-01-01

    The Cherenkov Telescope Array (CTA) observatory for very high-energy gamma rays will consist of about a hundred of imaging atmospheric Cherenkov telescopes (IACTs) of different size with a total reflective area of about 10,000 m$^2$. Here we present a novel technology for the production of IACT mirrors that has been developed in the Institute of Nuclear Physics PAS in Krakow, Poland. The mirrors are made by cold-slumping of the front reflecting aluminium-coated panel and the rear panel interspaced with aluminium spacers. Each panel is built of two glass panels laminated with a layer of a fibreglass tissue in between for reinforcement of the structure against mechanical damage. The mirror structure is open and does not require a perfect sealing needed in closed-type designs. It prohibits water to be trapped inside and enables a proper ventilation of the mirror. Full-size hexagonal prototype mirrors produced for the medium-sized CTA telescopes will be presented together with the results of recent comprehensive ...

  19. Measurements of Secodary Cosmic Microwave Background Anisotropies with the South Pole Telescope

    E-Print Network [OSTI]

    Lueker, Martin Van

    2010-01-01

    6 The South Pole Telescope Atmospheric Conditionsat the South Pole Telescope and Optical Design . . . . . . .interplay of cable delays, poles, resonances and zeroes in

  20. Software design for the control system for Small-Size Telescopes with single-mirror of the Cherenkov Telescope Array

    E-Print Network [OSTI]

    :,; B?ocki, J; Bogacz, L; Borkowski, J; Bulik, T; Cadoux, F; Christov, A; Cury?o, M; della Volpe, D; Dyrda, M; Favre, Y; Frankowski, A; Grudnik, ?; Grudzi?ska, M; Heller, M; Id?kowski, B; Jamrozy, M; Janiak, M; Kasperek, J; Lalik, K; Lyard, E; Mach, E; Mandat, D; Marsza?ek, A; Micha?owski, J; Moderski, R; Rameez, M; Montaruli, T; Neronov, A; Niemiec, J; Ostrowski, M; Pa?ko, P; Pech, M; Porcelli, A; Prandini, E; Rajda, P; Schioppa, E jr; Schovanek, P; Seweryn, K; Skowron, K; Sliusar, V; Sowi?ski, M; Stawarz, ?; Stodulska, M; Stodulski, M; Pujadas, I Troyano; Toscano, S; Walter, R; Wi?cek, M; Zagda?ski, A; Zi?tara, K; Zychowski, P

    2015-01-01

    The Small-Size Telescope with single-mirror (SST-1M) is a 4 m Davies-Cotton telescope and is among the proposed telescope designs for the Cherenkov Telescope Array (CTA). It is conceived to provide the high-energy ($>$ few TeV) coverage. The SST-1M contains proven technology for the telescope structure and innovative electronics and photosensors for the camera. Its design is meant to be simple, low-budget and easy-to-build industrially. Each device subsystem of an SST-1M telescope is made visible to CTA through a dedicated industrial standard server. The software is being developed in collaboration with the CTA Medium-Size Telescopes to ensure compatibility and uniformity of the array control. Early operations of the SST-1M prototype will be performed with a subset of the CTA central array control system based on the Alma Common Software (ACS). The triggered event data are time stamped, formatted and finally transmitted to the CTA data acquisition. The software system developed to control the devices of an SS...

  1. Large optics inspection, tilting, and washing stand

    DOE Patents [OSTI]

    Ayers, Marion Jay (Brentwood, CA); Ayers, Shannon Lee (Brentwood, CA)

    2010-08-24

    A large optics stand provides a risk free means of safely tilting large optics with ease and a method of safely tilting large optics with ease. The optics are supported in the horizontal position by pads. In the vertical plane the optics are supported by saddles that evenly distribute the optics weight over a large area.

  2. Large optics inspection, tilting, and washing stand

    DOE Patents [OSTI]

    Ayers, Marion Jay; Ayers, Shannon Lee

    2012-10-09

    A large optics stand provides a risk free means of safely tilting large optics with ease and a method of safely tilting large optics with ease. The optics are supported in the horizontal position by pads. In the vertical plane the optics are supported by saddles that evenly distribute the optics weight over a large area.

  3. DEEP MULTI-TELESCOPE PHOTOMETRY OF NGC 5466. I. BLUE STRAGGLERS AND BINARY SYSTEMS

    SciTech Connect (OSTI)

    Beccari, G.; Dalessandro, E.; Lanzoni, B.; Ferraro, F. R.; Miocchi, P.; Sollima, A.; Bellazzini, M.

    2013-10-10

    We present a detailed investigation of the radial distribution of blue straggler star (BSS) and binary populations in the Galactic globular cluster NGC 5466, over the entire extension of the system. We used a combination of data acquired with the Advanced Camera for Survey on board the Hubble Space Telescope, the LBC-blue mounted on the Large Binocular Telescope, and MEGACAM on the Canada-France-Hawaii Telescope. BSSs show a bimodal distribution with a mild central peak and a quite internal minimum. This feature is interpreted in terms of a relatively young dynamical age in the framework of the 'dynamical clock' concept proposed by Ferraro et al. The estimated fraction of binaries is ?6%-7% in the central region (r < 90'') and slightly lower (?5.5%) in the outskirts, at r > 200''. Quite interestingly, the comparison with the results of Milone et al. suggests that binary systems may also display a bimodal radial distribution, with the position of the minimum consistent with that of BSSs. If confirmed, this feature would give additional support to the scenario where the radial distribution of objects more massive than the average cluster stars is primarily shaped by the effect of dynamical friction. Moreover, this would also be consistent with the idea that the unperturbed evolution of primordial binaries could be the dominant BSS formation process in low-density environments.

  4. The ASTRI mini-array within the future Cherenkov Telescope Array

    E-Print Network [OSTI]

    Vercellone, Stefano

    2015-01-01

    The Cherenkov Telescope Array (CTA) is a large collaborative effort aimed at the design and operation of an observatory dedicated to very high-energy gamma-ray astrophysics in the energy range from a few tens of GeV to above 100 TeV, which will yield about an order of magnitude improvement in sensitivity with respect to the current major arrays (H.E.S.S., MAGIC, and VERITAS). Within this framework, the Italian National Institute for Astrophysics is leading the ASTRI project, whose main goals are the design and installation on Mt. Etna (Sicily) of an end-to-end dual-mirror prototype of the CTA small size telescope (SST) and the installation at the CTA Southern site of a dual-mirror SST mini-array composed of nine units with a relative distance of about 300 m. The innovative dual-mirror Schwarzschild-Couder optical solution adopted for the ASTRI Project allows us to substantially reduce the telescope plate-scale and, therefore, to adopt silicon photo-multipliers as light detectors. The ASTRI mini-array is a wid...

  5. Indirect Detection of Dark Matter in km-size Neutrino Telescopes

    E-Print Network [OSTI]

    Lars Bergstrom; Joakim Edsjo; Paolo Gondolo

    1999-06-02

    Neutrino telescopes of kilometer size are currently being planned. They will be two or three orders of magnitude larger than presently operating detectors, but they will have a much higher muon energy threshold. We discuss the trade-off between area and energy threshold for indirect detection of neutralino dark matter captured in the Sun and in the Earth and annihilating into high energy neutrinos. We also study the effect of a higher threshold on the complementarity of different searches for supersymmetric dark matter.

  6. The South Pole Telescope bolometer array and the measurement of secondary Cosmic Microwave Background anisotropy at small angular scales

    E-Print Network [OSTI]

    Shirokoff, Erik D.

    2011-01-01

    iii 2 The South Pole Telescope 2.1 The Telescope . . . . .modifications . . . . II The South Pole Telescope SZ Cameraand exciting as the South Pole Telescope. Fewer still do so

  7. Multiobjective optimization of a radio telescope array with site constraints

    E-Print Network [OSTI]

    Cohanim, Babak, 1980-

    2004-01-01

    The next generation of radio telescope interferometric arrays requires careful design of the array configuration to optimize the performance and minimize the cost of the overall system while adhering to site constraints. ...

  8. Design and optimization of lightweight space telescope structures

    E-Print Network [OSTI]

    Stewart, Andrzej Matthew

    2007-01-01

    As mankind attempts to look deeper into the universe, increasingly larger space telescopes will be needed to achieve the levels of resolution required to perform these missions. Due to this increase in size, increasing ...

  9. CTA telescopes as deep-space lasercom ground receivers

    E-Print Network [OSTI]

    Carrasco-Casado, Alberto; Vergaz, Ricardo

    2015-01-01

    The amount of scientific data to be transmitted from deep-space probes is very limited due to RF-communications constraints. Free-space optical communication can alleviate this bottleneck, increasing data rate while reducing weight, mass and power of communication onboard equipment. Nevertheless, optimizing the power delivery from spacecraft to Earth is needed. In RF communications, the strategy has been to increase the aperture of ground terminals. Free-space optical communications can also follow it, as they share the limitation of low power received on Earth. As the cost of big telescopes increases exponentially with aperture, new ideas are required to maximize the aperture-to-cost ratio. This work explores the feasibility of using telescopes of the future Cherenkov Telescope Array as optical-communication ground stations. Ground-based gamma-ray astronomy has the same power limitation, hence Cherenkov telescopes are designed to maximize receiver's aperture with minimum cost and some relaxed requirements. B...

  10. Robotic Telescopes and Networks: New Tools for Education and Science

    E-Print Network [OSTI]

    F. R. Querci; M. Querci

    1999-11-02

    Nowadays many telescopes around the world are automated and some networks of robotic telescopes are active or planned as shown by the lists we draw up. Such equipment could be used for the training of students and for science in the Universities of Developing Countries and of New Astronomical Countries, by sending them observational data via Internet or through remotely controlled telescopes. It seems that it is time to open up for discussion with UN and ESA organizations and also with IAU, how to implement links between robotic telescopes and such Universities applying for collaborations. Many scientific fields could thus be accessible to them, for example on stellar variability, near-earth object follow-up, gamma-ray burst counterpart tracking, and so on.

  11. South Pole Telescope Software Systems: Control, Monitoring, and Data Acquisition

    E-Print Network [OSTI]

    Story, K; Ade, P; Aird, K A; Austermann, J E; Beall, J A; Becker, D; Bender, A N; Benson, B A; Bleem, L E; Britton, J; Carlstrom, J E; Chang, C L; Chiang, H C; Cho, H-M; Crawford, T M; Crites, A T; Datesman, A; de Haan, T; Dobbs, M A; Everett, W; Ewall-Wice, A; George, E M; Halverson, N W; Harrington, N; Henning, J W; Hilton, G C; Holzapfel, W L; Hoover, S; Huang, N; Hubmayr, J; Irwin, K D; Karfunkle, M; Keisler, R; Kennedy, J; Lee, A T; Li, D; Lueker, M; Marrone, D P; McMahon, J J; Mehl, J; Meyer, S S; Montgomery, J; Montroy, T E; Nagy, J; Natoli, T; Nibarger, J P; Niemack, M D; Novosad, V; Padin, S; Pryke, C; Reichardt, C L; Ruhl, J E; Saliwanchik, B R; Sayre, J T; Schaffer, K K; Shirokoff, E; Smecher, G; Stalder, B; Tucker, C; Vanderlinde, K; Vieira, J D; Wang, G; Williamson, R; Yefremenko, V; Yoon, K W; Young, E; 10.1117/12.925808

    2012-01-01

    We present the software system used to control and operate the South Pole Telescope. The South Pole Telescope is a 10-meter millimeter-wavelength telescope designed to measure anisotropies in the cosmic microwave background (CMB) at arcminute angular resolution. In the austral summer of 2011/12, the SPT was equipped with a new polarization-sensitive camera, which consists of 1536 transition-edge sensor bolometers. The bolometers are read out using 36 independent digital frequency multiplexing (\\dfmux) readout boards, each with its own embedded processors. These autonomous boards control and read out data from the focal plane with on-board software and firmware. An overall control software system running on a separate control computer controls the \\dfmux boards, the cryostat and all other aspects of telescope operation. This control software collects and monitors data in real-time, and stores the data to disk for transfer to the United States for analysis.

  12. A generation of astronomical telescopes, their users, and publications

    E-Print Network [OSTI]

    Trimble, V

    2010-01-01

    Tele- scope in the Canary Islands, followed by 7 mirrors ofTelescopia Canarias in the Canary Islands. Table 3 attemptsKea, Hawaii, and the Canary Islands) have many telescopes

  13. The first GCT camera for the Cherenkov Telescope Array

    E-Print Network [OSTI]

    ,

    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.

  14. NectarCAM : a camera for the medium size telescopes of the Cherenkov Telescope Array

    E-Print Network [OSTI]

    Glicenstein, J-F; Barrio, J-A; Blanch~Bigas, O; Bolmont, J; Bouyjou, F; Brun, P; Chabanne, E; Champion, C; Colonges, S; Corona, P; Delagnes, E; Delgado, C; Ginzov, C Diaz; Durand, D; Ernenwein, J-P; Fegan, S; Ferreira, O; Fesquet, M; Fiasson, A; Fontaine, G; Fouque, N; Gascon, D; Giebels, B; Henault, F; Hermel, R; Hoffmann, D; Horan, D; Houles, J; Jean, P; Jocou, L; Karkar, S; Knoedlseder, J; Kossakowski, R; Lamanna, G; LeFlour, T; Lenain, J-P; Leveque, A; Louis, F; Martinez, G; Moudden, Y; Moulin, E; Nayman, P; Nunio, F; Olive, J-F; Panazol, J-L; Pavy, S; Petrucci, P-O; Pierre, E; Prast, J; Punch, M; Ramon, P; Rateau, S; Ravel, T; Rosier-Lees, S; Sanuy, A; Shayduk, M; Sizun, P-Y; Sulanke, K-H; Tavernet, J-P; Tejedor~Alvarez, L-A; Toussenel, F; Vasileiadis, G; Voisin, V; Waegebert, V; Wischnewski, R

    2015-01-01

    NectarCAM is a camera proposed for the medium-sized telescopes of the Cherenkov Telescope Array (CTA) covering the central energy range of ~100 GeV to ~30 TeV. It has a modular design and is based on the NECTAr chip, at the heart of which is a GHz sampling Switched Capacitor Array and a 12-bit Analog to Digital converter. The camera will be equipped with 265 7-photomultiplier modules, covering a field of view of 8 degrees. Each module includes the photomultiplier bases, high voltage supply, pre-amplifier, trigger, readout and Ethernet transceiver. The recorded events last between a few nanoseconds and tens of nanoseconds. The camera trigger will be flexible so as to minimize the read-out dead-time of the NECTAr chips. NectarCAM is designed to sustain a data rate of more than 4 kHz with less than 5\\% dead time. The camera concept, the design and tests of the various subcomponents and results of thermal and electrical prototypes are presented. The design includes the mechanical structure, cooling of the electro...

  15. A versatile digital camera trigger for telescopes in the Cherenkov Telescope Array

    E-Print Network [OSTI]

    Schwanke, U; Sulanke, K -H; Vorobiov, S; Wischnewski, R

    2015-01-01

    This paper describes the concept of an FPGA-based digital camera trigger for imaging atmospheric Cherenkov telescopes, developed for the future Cherenkov Telescope Array (CTA). The proposed camera trigger is designed to select images initiated by the Cherenkov emission of extended air showers from very-high energy (VHE, E>20 GeV) photons and charged particles while suppressing signatures from background light. The trigger comprises three stages. A first stage employs programmable discriminators to digitize the signals arriving from the camera channels (pixels). At the second stage, a grid of low-cost FPGAs is used to process the digitized signals for camera regions with 37 pixels. At the third stage, trigger conditions found independently in any of the overlapping 37-pixel regions are combined into a global camera trigger by few central FPGAs. Trigger prototype boards based on Xilinx FPGAs have been designed, built and tested and were shown to function properly. Using these components a full camera trigger wi...

  16. Satellite Characterization of four candidate sites for the Cherenkov Telescope Array telescope

    E-Print Network [OSTI]

    Cavazzani, S; Bulik, T; Ortolani, S

    2012-01-01

    In this paper we have evaluated the amount of available telescope time at four sites which are candidate to host the future Cherenkov Telescope Array (CTA). We use the GOES 12 data for the years 2008 and 2009. We use a homogeneous methodology presented in several previous papers to classify the nights as clear (completely cloud-free), mixed (partially cloud-covered), and covered. Additionally, for the clear nights, we have evaluated the amount of satellite stable nights which correspond to the amount of ground based photometric nights, and the clear nights corresponding to the spectroscopic nights. We have applied this model to two sites in the Northern Hemisphere (San Pedro Martir (SPM), Mexico; Izana, Canary Islands) and to two sites in the Southern Hemisphere (El Leoncito, Argentine; San Antonio de Los Cobres (SAC), Argentine). We have obtained, from the two years considered, a mean amount of cloud free nights of 68.6% at Izana, 76.0% at SPM, 70.6% at Leoncito and 70.0% at SAC. We have evaluated, among the...

  17. No. 16 ISSN 10278389 March 2012 The Southern African Large Telescope (Courtesy: S.B. Potter)

    E-Print Network [OSTI]

    Jarrett, Thomas H.

    P. Martinez South Africa Editor: wgssa@saao.ac.za P. Spargo South Africa P. Okeke Nigeria misunn-East and Africa. In partic- ular, the completion of HESS (the High Energy Stereoscopic System, in Namibia-class observational capability from ultra-high energy gamma-rays, through optical/near-IR to radio wave- lengths

  18. Early science with the large millimeter telescope: exploring the effect of

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing(Journal Article) | SciTech ConnectExperimentsGAMMA-RAY ATTENUATION UP TO THEAGN

  19. The Sloan Digital Sky Survey Monitor Telescope Pipeline

    E-Print Network [OSTI]

    D. L. Tucker; S. Kent; M. W. Richmond; J. Annis; J. A. Smith; S. S. Allam; C. T. Rodgers; J. L. Stute; J. K. Adelman-McCarthy; J. Brinkmann; M. Doi; D. Finkbeiner; M. Fukugita; J. Goldston; B. Greenway; J. E. Gunn; J. S. Hendry; D. W. Hogg; S. -I. Ichikawa; Z. Ivezic; G. R. Knapp; H. Lampeitl; B. C. Lee; H. Lin; T. A. McKay; A. Merrelli; J. A. Munn; E. H. Neilsen, Jr.; H. J. Newberg; G. T. Richards; D. J. Schlegel; C. Stoughton; A. Uomoto; B. Yanny

    2006-08-26

    The photometric calibration of the Sloan Digital Sky Survey (SDSS) is a multi-step process which involves data from three different telescopes: the 1.0-m telescope at the US Naval Observatory (USNO), Flagstaff Station, Arizona (which was used to establish the SDSS standard star network); the SDSS 0.5-m Photometric Telescope (PT) at the Apache Point Observatory (APO), New Mexico (which calculates nightly extinctions and calibrates secondary patch transfer fields); and the SDSS 2.5-m telescope at APO (which obtains the imaging data for the SDSS proper). In this paper, we describe the Monitor Telescope Pipeline, MTPIPE, the software pipeline used in processing the data from the single-CCD telescopes used in the photometric calibration of the SDSS (i.e., the USNO 1.0-m and the PT). We also describe transformation equations that convert photometry on the USNO-1.0m u'g'r'i'z' system to photometry the SDSS 2.5m ugriz system and the results of various validation tests of the MTPIPE software. Further, we discuss the semi-automated PT factory, which runs MTPIPE in the day-to-day standard SDSS operations at Fermilab. Finally, we discuss the use of MTPIPE in current SDSS-related projects, including the Southern u'g'r'i'z' Standard Star project, the u'g'r'i'z' Open Star Clusters project, and the SDSS extension (SDSS-II).

  20. The Sloan Digital Sky Survey Monitor Telescope Pipeline

    E-Print Network [OSTI]

    Tucker, D L; Richmond, M W; Annis, J; Smith, J A; Allam, S S; Rodgers, C T; Stute, J L; Adelman-McCarthy, J K; Brinkmann, J; Doi, M; Finkbeiner, D; Fukugita, M; Goldston, J; Greenway, B; Gunn, J E; Hendry, J S; Hogg, D W; Ichikawa, S I; Ivezic, Z; Knapp, G R; Lampeitl, H; Lee, B C; Lin, H; McKay, T A; Merrelli, A; Munn, J A; Neilsen, E H; Newberg, H J; Richards, G T; Schlegel, D J; Stoughton, C; Uomoto, A; Yanny, B

    2006-01-01

    The photometric calibration of the Sloan Digital Sky Survey (SDSS) is a multi-step process which involves data from three different telescopes: the 1.0-m telescope at the US Naval Observatory (USNO), Flagstaff Station, Arizona (which was used to establish the SDSS standard star network); the SDSS 0.5-m Photometric Telescope (PT) at the Apache Point Observatory (APO), New Mexico (which calculates nightly extinctions and calibrates secondary patch transfer fields); and the SDSS 2.5-m telescope at APO (which obtains the imaging data for the SDSS proper). In this paper, we describe the Monitor Telescope Pipeline, MTPIPE, the software pipeline used in processing the data from the single-CCD telescopes used in the photometric calibration of the SDSS (i.e., the USNO 1.0-m and the PT). We also describe transformation equations that convert photometry on the USNO-1.0m u'g'r'i'z' system to photometry the SDSS 2.5m ugriz system and the results of various validation tests of the MTPIPE software. Further, we discuss the s...

  1. Distance determinations to shield galaxies from Hubble space telescope imaging

    SciTech Connect (OSTI)

    McQuinn, Kristen B. W.; Skillman, Evan D. [Minnesota Institute for Astrophysics, School of Physics and Astronomy, University of Minnesota, 116 Church Street, S.E., Minneapolis, MN 55455 (United States); Cannon, John M.; Cave, Ian [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States); Dolphin, Andrew E. [Raytheon Company, 1151 E. Hermans Road, Tucson, AZ 85756 (United States); Salzer, John J. [Department of Astronomy, Indiana University, 727 East 3rd Street, Bloomington, IN 47405 (United States); Haynes, Martha P.; Adams, Elizabeth; Giovanelli, Riccardo [Center for Radiophysics and Space Research, Space Sciences Building, Cornell University, Ithaca, NY 14853 (United States); Elson, Ed C. [Astrophysics, Cosmology and Gravity Centre (ACGC), Department of Astronomy, University of Cape Town, Private Bag X3, Rondebosch 7701 (South Africa); Ott, Juërgen [National Radio Astronomy Observatory, P.O. Box O, 1003 Lopezville Road, Socorro, NM 87801 (United States); Saintonge, Amélie, E-mail: kmcquinn@astro.umn.edu [Max-Planck-Institute for Astrophysics, D-85741 Garching (Germany)

    2014-04-10

    The Survey of H I in Extremely Low-mass Dwarf (SHIELD) galaxies is an ongoing multi-wavelength program to characterize the gas, star formation, and evolution in gas-rich, very low-mass galaxies. The galaxies were selected from the first ?10% of the H I Arecibo Legacy Fast ALFA (ALFALFA) survey based on their inferred low H I mass and low baryonic mass, and all systems have recent star formation. Thus, the SHIELD sample probes the faint end of the galaxy luminosity function for star-forming galaxies. Here, we measure the distances to the 12 SHIELD galaxies to be between 5 and 12 Mpc by applying the tip of the red giant method to the resolved stellar populations imaged by the Hubble Space Telescope. Based on these distances, the H I masses in the sample range from 4 × 10{sup 6} to 6 × 10{sup 7} M {sub ?}, with a median H I mass of 1 × 10{sup 7} M {sub ?}. The tip of the red giant branch distances are up to 73% farther than flow-model estimates in the ALFALFA catalog. Because of the relatively large uncertainties of flow-model distances, we are biased toward selecting galaxies from the ALFALFA catalog where the flow model underestimates the true distances. The measured distances allow for an assessment of the native environments around the sample members. Five of the galaxies are part of the NGC 672 and NGC 784 groups, which together constitute a single structure. One galaxy is part of a larger linear ensemble of nine systems that stretches 1.6 Mpc from end to end. Three galaxies reside in regions with 1-9 neighbors, and four galaxies are truly isolated with no known system identified within a radius of 1 Mpc.

  2. Deep multi-telescope photometry of NGC 5466. II. The radial behaviour of the mass function slope

    E-Print Network [OSTI]

    Beccari, Giacomo; Lanzoni, Barbara; Ferraro, Francesco R; Bellazzini, Michele; Sollima, Antonio

    2015-01-01

    We use a combination of data acquired with the Advanced Camera for Survey (ACS) on board the Hubble Space Telescope and the Large Binocular Camera (LBC-blue) mounted on the Large Binocular Telescope, to sample the main sequence stars of the globular cluster NGC~5466 in the mass range $0.3tidal radius. After corrections for incompleteness and field-contamination, this has been compared to theoretical Luminosity Functions, obtained by multiplying a simple power law Mass Function in the form dN/dm$ \\propto m^{\\alpha}$ by the derivative of the mass-luminosity relationship of the best-fit isochrone. We find that $\\alpha$ varies from -0.6 in the core region to -1.9 in the outer region. This fact allows us to observationally prove that the stars in NGC 5466 have experienced the effects of mass segregation. We compare the radial variation of $\\alpha$ from the center out to 5 core rad...

  3. The software design of the Gemini 8m telescopes Stephen Wampler

    E-Print Network [OSTI]

    The software design of the Gemini 8m telescopes Stephen Wampler Gemini 8m Telescopes Project, 950 N. Cherry Ave, Tucson, AZ 85726 ABSTRACT The design of the software for the Gemini 8m Telescopes is nearly. Keywords: telescope software design, design processes, Gemini software 1. INTRODUCTION The Gemini 8m

  4. QUIESCENT PROMINENCE DYNAMICS OBSERVED WITH THE HINODE SOLAR OPTICAL TELESCOPE. I. TURBULENT UPFLOW PLUMES

    SciTech Connect (OSTI)

    Berger, Thomas E.; Slater, Gregory; Hurlburt, Neal; Shine, Richard; Tarbell, Theodore; Title, Alan; Okamoto, Takenori J.; Ichimoto, Kiyoshi; Katsukawa, Yukio; Magara, Tetsuya; Suematsu, Yoshinori; Shimizu, Toshifumi

    2010-06-20

    Hinode/Solar Optical Telescope (SOT) observations reveal two new dynamic modes in quiescent solar prominences: large-scale (20-50 Mm) 'arches' or 'bubbles' that 'inflate' from below into prominences, and smaller-scale (2-6 Mm) dark turbulent upflows. These novel dynamics are related in that they are always dark in visible-light spectral bands, they rise through the bright prominence emission with approximately constant speeds, and the small-scale upflows are sometimes observed to emanate from the top of the larger bubbles. Here we present detailed kinematic measurements of the small-scale turbulent upflows seen in several prominences in the SOT database. The dark upflows typically initiate vertically from 5 to 10 Mm wide dark cavities between the bottom of the prominence and the top of the chromospheric spicule layer. Small perturbations on the order of 1 Mm or less in size grow on the upper boundaries of cavities to generate plumes up to 4-6 Mm across at their largest widths. All plumes develop highly turbulent profiles, including occasional Kelvin-Helmholtz vortex 'roll-up' of the leading edge. The flows typically rise 10-15 Mm before decelerating to equilibrium. We measure the flowfield characteristics with a manual tracing method and with the Nonlinear Affine Velocity Estimator (NAVE) 'optical flow' code to derive velocity, acceleration, lifetime, and height data for several representative plumes. Maximum initial speeds are in the range of 20-30 km s{sup -1}, which is supersonic for a {approx}10,000 K plasma. The plumes decelerate in the final few Mm of their trajectories resulting in mean ascent speeds of 13-17 km s{sup -1}. Typical lifetimes range from 300 to 1000 s ({approx}5-15 minutes). The area growth rate of the plumes (observed as two-dimensional objects in the plane of the sky) is initially linear and ranges from 20,000 to 30,000 km{sup 2} s{sup -1} reaching maximum projected areas from 2 to 15 Mm{sup 2}. Maximum contrast of the dark flows relative to the bright prominence plasma in SOT images is negative and ranges from -10% for smaller flows to -50% for larger flows. Passive scalar 'cork movies' derived from NAVE measurements show that prominence plasma is entrained by the upflows, helping to counter the ubiquitous downflow streams in the prominence. Plume formation shows no clear temporal periodicity. However, it is common to find 'active cavities' beneath prominences that can spawn many upflows in succession before going dormant. The mean flow recurrence time in these active locations is roughly 300-500 s (5-8 minutes). Locations remain active on timescales of tens of minutes up to several hours. Using a column density ratio measurement and reasonable assumptions on plume and prominence geometries, we estimate that the mass density in the dark cavities is at most 20% of the visible prominence density, implying that a single large plume could supply up to 1% of the mass of a typical quiescent prominence. We hypothesize that the plumes are generated from a Rayleigh-Taylor instability taking place on the boundary between the buoyant cavities and the overlying prominence. Characteristics, such as plume size and frequency, may be modulated by the strength and direction of the cavity magnetic field relative to the prominence magnetic field. We conclude that buoyant plumes are a source of quiescent prominence mass as well as a mechanism by which prominence plasma is advected upward, countering constant gravitational drainage.

  5. TARGET: toward a solution for the readout electronics of the Cherenkov Telescope Array

    E-Print Network [OSTI]

    Tibaldo, L; Albert, A M; Funk, S; Kawashima, T; Kraus, M; Okumura, A; Sapozhnikov, L; Tajima, H; Varner, G S; Wu, T; Zink, A

    2015-01-01

    TARGET is an application specific integrated circuit (ASIC) designed to read out signals recorded by the photosensors in cameras of very-high-energy gamma-ray telescopes exploiting the imaging of Cherenkov radiation from atmospheric showers. TARGET capabilities include sampling at a high rate (typically 1 GSample/s), digitization, and triggering on the sum of four adjacent pixels. The small size, large number of channels read out per ASIC (16), low cost per channel, and deep buffer for trigger latency (~16 $\\mu$s at 1 GSample/s) make TARGET ideally suited for the readout in systems with a large number of telescopes instrumented with compact photosensors like multi-anode or silicon photomultipliers combined with dual-mirror optics. The possible advantages of such systems are better sensitivity, a larger field of view, and improved angular resolution. The two latest generations of TARGET ASICs, TARGET 5 and TARGET 7, are soon to be used for the first time in two prototypes of small-sized and medium-sized dual-m...

  6. Large forging manufacturing process

    DOE Patents [OSTI]

    Thamboo, Samuel V. (Latham, NY); Yang, Ling (Niskayuna, NY)

    2002-01-01

    A process for forging large components of Alloy 718 material so that the components do not exhibit abnormal grain growth includes the steps of: a) providing a billet with an average grain size between ASTM 0 and ASTM 3; b) heating the billet to a temperature of between 1750.degree. F. and 1800.degree. F.; c) upsetting the billet to obtain a component part with a minimum strain of 0.125 in at least selected areas of the part; d) reheating the component part to a temperature between 1750.degree. F. and 1800.degree. F.; e) upsetting the component part to a final configuration such that said selected areas receive no strains between 0.01 and 0.125; f) solution treating the component part at a temperature of between 1725.degree. F. and 1750.degree. F.; and g) aging the component part over predetermined times at different temperatures. A modified process achieves abnormal grain growth in selected areas of a component where desirable.

  7. Water Vapour Radiometers for the Australia Telescope Compact Array

    E-Print Network [OSTI]

    Indermuehle, Balthasar T; Crofts, Jonathan

    2012-01-01

    We have developed Water Vapour Radiometers (WVRs) for the Australia Telescope Compact Array (ATCA) that are capable of determining path fluctuations by virtue of measuring small temperature fluctuations in the atmosphere using the 22.2 GHz water vapour line for each of the six antennae. By measuring the line of sight variations of the water vapour, the induced path excess and thus the phase delay can be estimated and corrections can then be applied during data reduction. This reduces decorrelation of the source signal. We demonstrate how this recovers the telescope's efficiency and image quality as well as how this improves the telescope's ability to use longer baselines at higher frequencies, thereby resulting in higher spatial resolution. A description of the WVR hardware design, their calibration and water vapour retrieval mechanism is given.

  8. The Very Energetic Radiation Imaging Telescope Array System (VERITAS)

    E-Print Network [OSTI]

    Bradbury, S M; Breslin, A C; Buckley, J H; Carter-Lewis, D A; Catanese, M; Criswell, S; Dingus, B L; Fegan, D J; Finley, J P; Gaidos, J A; Grindlay, J; Hillas, A M; Harris, K; Hermann, G; Kaaret, P E; Kieda, D B; Knapp, J; Krennrich, F; Le Bohec, S; Lessard, R W; Lloyd-Evans, J; McKernan, B; Müller, D; Ong, R; Quenby, J J; Quinn, J; Rochester, G D; Rose, H J; Salamon, M B; Sembroski, G H; Sumner, T J; Swordy, S P; Vasilev, V; Weekes, T C

    1999-01-01

    We give an overview of the current status and scientific goals of VERITAS, a proposed hexagonal array of seven 10 m aperture imaging Cherenkov telescopes. The selected site is Montosa Canyon (1390 m a.s.l.) at the Whipple Observatory, Arizona. Each telescope, of 12 m focal length, will initially be equipped with a 499 element photomultiplier camera covering a 3.5 degree field of view. A central station will initiate the readout of 500 MHz FADCs upon receipt of multiple telescope triggers. The minimum detectable flux sensitivity will be 0.5% of the Crab Nebula flux at 200 GeV. Detailed simulations of the array's performance are presented elsewhere at this meeting. VERITAS will operate primarily as a gamma-ray observatory in the 50 GeV to 50 TeV range for the study of active galaxies, supernova remnants, pulsars and gamma-ray bursts.

  9. The Very Energetic Radiation Imaging Telescope Array System (VERITAS)

    E-Print Network [OSTI]

    S. M. Bradbury; I. H. Bond; A. C. Breslin; J. H. Buckley; D. A. Carter-Lewis; M. Catanese; S. Criswell; B. L. Dingus; D. J. Fegan; J. P. Finley; J. Gaidos; J. Grindlay; A. M. Hillas; K. Harris; G. Hermann; P. Kaaret; D. Kieda; J. Knapp; F. Krennrich; S. LeBohec; R. W. Lessard; J. Lloyd-Evans; B. McKernan; D. Mueller; R. Ong; J. J. Quenby; J. Quinn; G. Rochester; H. J. Rose; M. Salamon; G. H. Sembroski; T. Sumner; S. Swordy; V. V. Vassiliev; T. C. Weekes

    1999-07-19

    We give an overview of the current status and scientific goals of VERITAS, a proposed hexagonal array of seven 10 m aperture imaging Cherenkov telescopes. The selected site is Montosa Canyon (1390 m a.s.l.) at the Whipple Observatory, Arizona. Each telescope, of 12 m focal length, will initially be equipped with a 499 element photomultiplier camera covering a 3.5 degree field of view. A central station will initiate the readout of 500 MHz FADCs upon receipt of multiple telescope triggers. The minimum detectable flux sensitivity will be 0.5% of the Crab Nebula flux at 200 GeV. Detailed simulations of the array's performance are presented elsewhere at this meeting. VERITAS will operate primarily as a gamma-ray observatory in the 50 GeV to 50 TeV range for the study of active galaxies, supernova remnants, pulsars and gamma-ray bursts.

  10. The Antarctic Submillimeter Telescope and Remote Observatory (AST/RO)

    E-Print Network [OSTI]

    Antony A. Stark; John Bally; Simon P. Balm; T. M. Bania; Alberto D. Bolatto; Richard A. Chamberlin; Gregory Engargiola; Maohai Huang; James G. Ingalls; Karl Jacobs; James M. Jackson; Jacob W. Kooi; Adair P. Lane; K. -Y. Lo; Rodney D. Marks; Christopher L. Martin; Dennis Mumma; Roopesh Ojha; Rudolf Schieder; Johannes Staguhn; Juergen Stutzki; Christopher K. Walker; Robert W. Wilson; Gregory A. Wright; Xiaolei Zhang; Peter Zimmermann; Ruediger Zimmermann

    2000-12-15

    AST/RO, a 1.7 m diameter telescope for astronomy and aeronomy studies at wavelengths between 200 and 2000 microns, was installed at the South Pole during the 1994-1995 Austral summer. The telescope operates continuously through the Austral winter, and is being used primarily for spectroscopic studies of neutral atomic carbon and carbon monoxide in the interstellar medium of the Milky Way and the Magellanic Clouds. The South Pole environment is unique among observatory sites for unusually low wind speeds, low absolute humidity, and the consistent clarity of the submillimeter sky. Four heterodyne receivers, an array receiver, three acousto-optical spectrometers, and an array spectrometer are installed. A Fabry-Perot spectrometer using a bolometric array and a Terahertz receiver are in development. Telescope pointing, focus, and calibration methods as well as the unique working environment and logistical requirements of the South Pole are described.

  11. The X-ray Telescope of the CAST Experiment

    E-Print Network [OSTI]

    R. Kotthaus; H. Braeuninger; P. Friedrich; R. Hartmann; D. Kang; M. Kuster; G. Lutz; L. Strueder

    2005-11-14

    The CERN Axion Solar Telescope (CAST) searches for solar axions employing a 9 Tesla superconducting dipole magnet equipped with 3 independent detection systems for X-rays from axion-photon conversions inside the 10 m long magnetic field. Results of the first 6 months of data taking in 2003 imply a 95 % CL upper limit on the axion-photon coupling constant of 1.16x10(-10) GeV(-1) for axion masses CAST is a X-ray telescope consisting of a Wolter I type mirror system and a fully depleted pn-CCD as focal plane detector. Exploiting the full potential of background suppression by focussing X-rays emerging from the magnet bore, the axion sensitivity obtained with telescope data taken in 2004, for the first time in a controlled laboratory experiment, will supersede axion constraints derived from stellar energy loss arguments.

  12. An EUDET/AIDA Pixel Beam Telescope for Detector Development

    E-Print Network [OSTI]

    Rubinskiy, I

    2015-01-01

    Ahigh resolution(?International Linear Collider providing test beam infrastructure to detector R&D groups. The telescope consists of six sensor planes with a pixel pitch of either 18.4 ?m or 10 ?mand canbe operated insidea solenoidal magnetic fieldofupto1.2T.Ageneral purpose cooling, positioning, data acquisition (DAQ) and offine data analysis tools are available for the users. The excellent resolution, readout rate andDAQintegration capabilities made the telescopea primary beam tests tool also for several CERN based experiments. In this report the performance of the final telescope is presented. The plans for an even more flexible telescope with three differentpixel technologies(ATLASPixel, Mimosa,Timepix) withinthenew European detector infrastructure project AIDA are presented.

  13. MACHO Mass Determination Based on Space Telescope Observation

    E-Print Network [OSTI]

    Mareki Honma

    1999-03-24

    We investigate the possibility of lens mass determination for a caustic crossing microlensing event based on a space telescope observation. We demonstrate that the parallax due to the orbital motion of a space telescope causes a periodic fluctuation of the light curve, from which the lens distance can be derived. Since the proper motion of the lens relative to the source is also measurable for a caustic crossing event, one can find a full solution for microlensing properties of the event, including the lens mass. To determine the lens mass with sufficient accuracy, the light curve near the caustic crossing should be observed within uncertainty of $\\sim$ 1%. We argue that the Hubble Space Telescope observation of the caustic crossing supplied with ground-based observations of the full light curve will enable us to determine the mass of MACHOs, which is crucial for understanding the nature of MACHOs.

  14. Lee Sang Gak Telescope (LSGT): A Remotely Operated Robotic Telescope for Education and Research at Seoul National University

    E-Print Network [OSTI]

    Im, Myungshin; Kim, Kihyun

    2015-01-01

    We introduce the Lee Sang Gak Telescope (LSGT), a remotely operated, robotic 0.43-meter telescope. The telescope was installed at the Siding Spring Observatory, Australia, in 2014 October, to secure regular and exclusive access to the dark sky and excellent atmospheric conditions in the southern hemisphere from the Seoul National University (SNU) campus. Here, we describe the LSGT system and its performance, present example images from early observations, and discuss a future plan to upgrade the system. The use of the telescope includes (i) long-term monitoring observations of nearby galaxies, active galactic nuclei, and supernovae; (ii) rapid follow-up observations of transients such as gamma-ray bursts and gravitational wave sources; and (iii) observations for educational activities at SNU. Based on observations performed so far, we find that the telescope is capable of providing images to a depth of R=21.5 mag (point source detection) at 5-sigma with 15 min total integration time under good observing condi...

  15. Proposal of a new generation of Laser Beacon for time calibration in the KM3NeT neutrino telescope

    SciTech Connect (OSTI)

    Real, Diego [IFIC, Instituto de Física Corpuscular, CSIC-Universidad de Valencia, C Collaboration: KM3NeT Collaboration

    2014-11-18

    The KM3NeT collaboration aims at the construction of a multi-km3 high-energy neutrino telescope in the Mediterranean Sea consisting of a matrix of pressure resistant glass spheres holding each a set (31) of small area photomultipliers. The main motivation of the telescope is to observe cosmic neutrinos through the Cherenkov light induced in sea water by charged particles produced in neutrino interactions with the surrounding medium. A relative time calibration between photomultipliers of the order of 1 ns is required to achieve an optimal performance. To this end, several time calibration subsystems have been developed. In this article, the proposal of a last generation Laser Beacon, to be used in KM3NeT and developed to measure and monitor the relative time offsets between photomultipliers, is presented.

  16. Calibration of the Milagro Cosmic Ray Telescope

    E-Print Network [OSTI]

    Atkins, R; Berley, D; Chen, M L; Coyne, D G; Delay, R S; Dingus, B L; Dorfan, D E; Ellsworth, R W; Evans, D; Falcone, A D; Fleysher, L; Fleysher, R; Gisler, G; Goodman, J A; Haines, T J; Hoffman, C M; Hugenberger, S; Kelley, L A; Leonor, I; Macri, J R; McConnell, M; McCullough, J F; McEnery, J E; Miller, R S; Mincer, A I; Morales, M F; Némethy, P; Ryan, J M; Schneider, M; Shen, B; Shoup, A L; Sinnis, G; Smith, A J; Sullivan, G W; Thompson, T N; Tümer, T O; Wang, K; Wascko, M O; Westerhoff, S; Williams, D A; Yang, T; Yodh, G B

    1999-01-01

    The Milagro detector is an air shower array which uses the water Cherenkov technique and is capable of continuously monitoring the sky at energies near 1 TeV. The detector consists of 20000 metric tons of pure water instrumented with 723 photo-multiplier tubes (PMTs). The PMTs are arranged in a two-layer structure on a lattice of 3 m spacing covering 5000 $m^2$ area. The direction of the shower is determined from the relative timing of the PMT signals, necessitating a common time reference and amplitude slewing corrections to improve the time resolution. The calibration system to provide these consists of a pulsed laser driving 30 diffusing light sources deployed in the pond to allow cross-calibration of the PMTs. The system is capable of calibrating times and the pulse-heights from the PMTs using the time-over-threshold technique. The absolute energy scale is provided using single muons passing through the detector. The description of the calibration system of the Milagro detector and its prototype Milagrito...

  17. Calibration of the Milagro Cosmic Ray Telescope

    E-Print Network [OSTI]

    R. Atkins; W. Benbow; D. Berley; M. -L. Chen; D. G. Coyne; R. S. Delay; B. L. Dingus; D. E. Dorfan; R. W. Ellsworth; D. Evans; A. Falcone; L. Fleysher; R. Fleysher; G. Gisler; J. A. Goodman; T. J. Haines; C. M. Hoffman; S. Hugenberger; L. A. Kelley; I. Leonor; J. Macri; M. McConnell; J. F. McCullough; J. E. McEnery; R. S. Miller; A. I. Mincer; M. F. Morales; P. Nemethy; J. M. Ryan; M. Schneider; B. Shen; A. Shoup; G. Sinnis; A. J. Smith; G. W. Sullivan; T. N. Thompson; O. T. Tumer; K. Wang; M. O. Wascko; S. Westerhoff; D. A. Williams; T. Yang; G. B. Yodh

    1999-06-25

    The Milagro detector is an air shower array which uses the water Cherenkov technique and is capable of continuously monitoring the sky at energies near 1 TeV. The detector consists of 20000 metric tons of pure water instrumented with 723 photo-multiplier tubes (PMTs). The PMTs are arranged in a two-layer structure on a lattice of 3 m spacing covering 5000 $m^2$ area. The direction of the shower is determined from the relative timing of the PMT signals, necessitating a common time reference and amplitude slewing corrections to improve the time resolution. The calibration system to provide these consists of a pulsed laser driving 30 diffusing light sources deployed in the pond to allow cross-calibration of the PMTs. The system is capable of calibrating times and the pulse-heights from the PMTs using the time-over-threshold technique. The absolute energy scale is provided using single muons passing through the detector. The description of the calibration system of the Milagro detector and its prototype Milagrito will be presented.

  18. Integrating Seeing Measurements into the Operations of Solar Telescopes

    E-Print Network [OSTI]

    years, experimental solar physics has seen renewed efforts to design, build and operate the nextIntegrating Seeing Measurements into the Operations of Solar Telescopes C. Denker and A. P. Verdoni New Jersey Institute of Technology, Center for Solar-Terrestrial Research 323 Martin Luther King Blvd

  19. Status and First Results of the MAGIC Telescope

    E-Print Network [OSTI]

    J. Cortina; for the MAGIC collaboration

    2004-07-22

    The 17 m MAGIC Cherenkov telescope for gamma ray astronomy between 30 and 300 GeV started operations in its final configuration in October 2003 and is currently well into its calibration phase. Here I report on its present status and its first gamma ray source detections.

  20. Detecting Earth-impacting asteroids Pan-STARRS prototype telescope

    E-Print Network [OSTI]

    Veres, Peter

    Detecting Earth-impacting asteroids with the Pan-STARRS prototype telescope (Based on MS. Grav #12;10/14/2008 DPS, Ithaca, NY Granvik: Earth-impacting asteroids with PS1 Pan-STARRS 1 (PS1) Moving Object Processing System (MOPS) #12;10/14/2008 DPS, Ithaca, NY Granvik: Earth-impacting asteroids

  1. The Hobby-Eberly Telescope Low Resolution Spectrograph: mechanical design

    E-Print Network [OSTI]

    Hill, Gary J.

    The Hobby-Eberly Telescope Low Resolution Spectrograph: mechanical design G. J. Hilla* , H. Nicklas constraints make the LRS a challenging instrument, built on a limited budget. The mechanical design of the mechanical design of the LRS. Fabrication, assembly and testing of the LRS will be completed by mid 1998

  2. The HobbyEberly Telescope Low Resolution Spectrograph: mechanical design

    E-Print Network [OSTI]

    Hill, Gary J.

    The Hobby­Eberly Telescope Low Resolution Spectrograph: mechanical design G. J. Hill a* , H constraints make the LRS a challenging instrument, built on a limited budget. The mechanical design of the mechanical design of the LRS. Fabrication, assembly and testing of the LRS will be completed by mid 1998

  3. Performance of the MAGIC telescopes after the major upgrade

    E-Print Network [OSTI]

    Sitarek, Julian; Colin, Pierre; Mazin, Daniel

    2015-01-01

    MAGIC is a system of two Imaging Atmospheric Cherenkov Telescopes located on the Canary island of La Palma, Spain. During summer 2011 and 2012 it underwent a major upgrade. The main subsystems upgraded were the MAGIC-I camera and its trigger system and the readout system of both telescopes. We use observations of the Crab Nebula taken at low and medium zenith angles to assess the key performance parameters of the MAGIC stereo system. For low zenith angle observations, the standard trigger threshold of the MAGIC telescopes is about 50 GeV. The integral sensitivity for point-like sources with Crab Nebula-like spectra above 220 GeV is (0.66 +/- 0.03)% of Crab Nebula flux in 50 h of observations. The angular resolution, defined as the sigma of a 2-dimensional Gaussian distribution, at energies of a few hundred GeV is below 0.07degree, while the energy resolution is around 16%. We investigate the effect of the systematic uncertainty on the data taken with the MAGIC telescopes after the upgrade. We estimate that th...

  4. The pier and building of the European Solar Telescope (EST) F.C.M. Bettonvil*a

    E-Print Network [OSTI]

    Rutten, Rob

    The pier and building of the European Solar Telescope (EST) F.C.M. Bettonvil*a , R. Codinab , A surrounded by an open framework. Keywords: Telescope pier, building, solar telescope, CFD analysis, tower. ABSTRACT EST (European Solar Telescope) is a 4-m class solar telescope, which is currently

  5. Engineering light using large area photonic crystal devices

    E-Print Network [OSTI]

    Tandon, Sheila (Sheila N.), 1978-

    2005-01-01

    Photonic crystals are fabricated structures composed of a periodic arrangement of materials with differing indices of refraction. This research has focused on the realization of two distinct photonic crystal structures in ...

  6. Apparatuses for large area radiation detection and related method

    DOE Patents [OSTI]

    Akers, Douglas W; Drigert, Mark W

    2015-04-28

    Apparatuses and a related method relating to radiation detection are disclosed. In one embodiment, an apparatus includes a first scintillator and a second scintillator adjacent to the first scintillator, with each of the first scintillator and second scintillator being structured to generate a light pulse responsive to interacting with incident radiation. The first scintillator is further structured to experience full energy deposition of a first low-energy radiation, and permit a second higher-energy radiation to pass therethrough and interact with the second scintillator. The apparatus further includes a plurality of light-to-electrical converters operably coupled to the second scintillator and configured to convert light pulses generated by the first scintillator and the second scintillator into electrical signals. The first scintillator and the second scintillator exhibit at least one mutually different characteristic for an electronic system to determine whether a given light pulse is generated by the first scintillator or the second scintillator.

  7. Thin Film Encapsulation Methods for Large Area MEMS Packaging

    E-Print Network [OSTI]

    Mahajerin, Armon

    2012-01-01

    include the use of very low outgassing die attach materialsand the removal of outgassing vapors during the curingminimize CTE mismatch Outgassing Stiction, corrosion Low

  8. Thin Film Encapsulation Methods for Large Area MEMS Packaging

    E-Print Network [OSTI]

    Mahajerin, Armon

    2012-01-01

    for polysilicon to electroplating for metals. Figure 2.12via sputtering, evaporation, or electroplating. Gold isbiocompatibility and ease of electroplating. One interesting

  9. Thin Film Encapsulation Methods for Large Area MEMS Packaging

    E-Print Network [OSTI]

    Mahajerin, Armon

    2012-01-01

    Brown, “Challenges in the Packaging of MEMS,” InternationalSymposium on Advanced Packaging Materials, pp. 41-47,Wafer-Level Chip Scale Packaging?: Benefits for Integrated

  10. Technical Design Update to Proposal for a Large Area

    E-Print Network [OSTI]

    Llope, William J.

    , A. Tai University of California - Los Angeles, Los Angeles, CA 90095 Hongfang Chen, Xin Dong, Cheng.1.1 Overview . . . . . . . . . . 56 6.1.2 New PMT bases for the start detector . . . . . . . . . . . 57 6 of the Run-5 Data 68 7.1 Analysis Details . . . . . . . . . . . 68 7.2 Basic Results

  11. Large area 3-D reconstructions from underwater optical surveys

    E-Print Network [OSTI]

    Singh, Hanumant

    Robotic underwater vehicles are regularly performing vast optical surveys of the ocean floor. Scientists value these surveys since optical images offer high levels of detail and are easily interpreted by humans. Unfortunately, ...

  12. Plasma and Ion Sources in Large Area Coatings: A Review

    E-Print Network [OSTI]

    Anders, Andre

    2005-01-01

    Rectangular filtered arc plasma source, Patent US5997705,multi-filament thermionic arc plasma generator and four-gridsources, and cathodic arc plasmas. In all of these sources,

  13. Thin Film Encapsulation Methods for Large Area MEMS Packaging

    E-Print Network [OSTI]

    Mahajerin, Armon

    2012-01-01

    Judy, “Microelectromechanical systems (MEMS): fabrication,Packaging of Microelectromechanical Systems (MEMS),” IEEEbased on microelectromechanical systems (MEMS). However, one

  14. Large area liquid argon detectors for interrogation systems

    SciTech Connect (OSTI)

    Gary, Charles; Kane, Steve; Firestone, Murray I.; Smith, Gregory [Adelphi Technology LLC, Purdue Technology Center, 5225 Exploration Drive, Indianapolis, IN 46241 (United States); Gozani, Tsahi; Brown, Craig; Kwong, John; King, Michael J. [Rapiscan Laboratories, 520 Almanor Avenue, Sunnyvale, CA 94085 (United States); Nikkel, James A.; McKinsey, Dan [Physics Department, Yale University, New Haven, CT 06520 (United States)

    2013-04-19

    Measurements of the efficiency, pulse shape, and energy and time resolution of liquid argon (LAr) detectors are presented. Liquefied noble gas-based (LNbG) detectors have been developed for the detection of dark matter and neutrinoless double-beta decay. However, the same qualities that make LNbG detectors ideal for these applications, namely their size, cost, efficiency, pulse shape discrimination and resolution, make them promising for portal screening and the detection of Special Nuclear Materials (SNM). Two 18-liter prototype detectors were designed, fabricated, and tested, one with pure LAr and the other doped with liquid Xe (LArXe). The LArXe detector presented the better time and energy resolution of 3.3 ns and 20% at 662 KeV, respectively. The total efficiency of the detector was measured to be 35% with 4.5% of the total photons detected in the photopeak.

  15. Thin Film Encapsulation Methods for Large Area MEMS Packaging

    E-Print Network [OSTI]

    Mahajerin, Armon

    2012-01-01

    P. J. French, “Robust Wafer-Level Thin-Film Encapsulation ofThe Elastic Properties of Thin- Film Silicon Nitride,” IEEELPCVD Silicon Nitride Thin Films at Cryogenic Temperatures,”

  16. Thin Film Encapsulation Methods for Large Area MEMS Packaging

    E-Print Network [OSTI]

    Mahajerin, Armon

    2012-01-01

    thick TEOS PECVD silicon oxide layers for integrated opticalselectively etch the bottom oxide layer, after which anotherprofile of 7.8 ?m thick oxide layer after 8 min HF vapor for

  17. Large area quantitative analysis of nanostructured thin-films

    E-Print Network [OSTI]

    Sliz, Rafal; Eneh, Chibuzor; Suzuki, Yuji; Czajkowski, Jakub; Fabritius, Tapio; Kathirgamanathan, Poopathy; Nathan, Arokia; Myllyla, Risto; Jabbour, Ghassan

    2015-01-09

    of SEM images of quantum dots and InP nanostructured thin-films are provided in the supple- mentary information. 3 Results 3.1 Physical Characterization The AFM and XRD techniques were used to verify the sur- face morphology and provide the reference... research subject for their high applicability in optoelectronics22–24. In addi- tion, self-assembled gold quantum dots and InP-based nanos- tructures were examined. Prior to the analysis, ZnO fabricated thin-films were additionally characterized with AFM...

  18. Thin Film Encapsulation Methods for Large Area MEMS Packaging

    E-Print Network [OSTI]

    Mahajerin, Armon

    2012-01-01

    such as aluminum or polyimide, which is becoming more commonsuch as Parylene-C or polyimide. These films are appealingOne reliable choice is polyimide, which has a low dielectric

  19. Thin Film Encapsulation Methods for Large Area MEMS Packaging

    E-Print Network [OSTI]

    Mahajerin, Armon

    2012-01-01

    Journal of Microelectromechanical Systems, vol. 2, no. 1,Journal of Microelectromechanical Systems, vol. 13, no. 5,Judy, “Microelectromechanical systems (MEMS): fabrication,

  20. Thin Film Encapsulation Methods for Large Area MEMS Packaging

    E-Print Network [OSTI]

    Mahajerin, Armon

    2012-01-01

    Machinery,” Journal of Microelectromechanical Systems, vol.Journal of Microelectromechanical Systems, vol. 13, no. 5,1995. J. W. Judy, “Microelectromechanical systems (MEMS):

  1. Thin Film Encapsulation Methods for Large Area MEMS Packaging

    E-Print Network [OSTI]

    Mahajerin, Armon

    2012-01-01

    stiction coatings for MEMS,” Sensors and Actuators A, vol.E. Jackson, “A Novel MEMS Pressure Sensor Fabricated on anIC package and (b) a MEMS pressure sensor package. [21] .

  2. Thin Film Encapsulation Methods for Large Area MEMS Packaging

    E-Print Network [OSTI]

    Mahajerin, Armon

    2012-01-01

    2, pp. 124-126, 1987. H. Fujita, “A Decade of MEMS and ItsFuture,” IEEE MEMS Conference Proceedings, pp. 1-8, 1997. K.in the Packaging of MEMS,” International Symposium on

  3. Large seasonal swings in leaf area of Amazon rainforests

    E-Print Network [OSTI]

    Myneni, Ranga B.

    tropical forests stud- ied to date display seasonal variations in the presence of new leaves, flowers of 25% in a majority of the Amazon rainforests. This seasonal cycle is timed to the seasonality of solar radiation in a manner that is suggestive of anticipatory and opportunistic pat- terns of net leaf flushing

  4. Finding Large Aperture Fractures in Geothermal Resource Areas Using a

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View New PagesSustainable Urban Transport Jump to: navigation, search Tool SummaryThree-Component

  5. Development of Large Area Gas Electron Multiplier Detector and Its

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnectlaser-solidSwitchgrass and Miscanthus x| SciTech

  6. Development of Large Area Gas Electron Multiplier Detector and Its

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnectlaser-solidSwitchgrass and Miscanthus x| SciTechApplication to a

  7. Transferred metal electrode films for large-area electronic devices

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory of rare Kaon and PionExperiments (Journallithium(Journal Article) | SciTech

  8. Finding Large Aperture Fractures in Geothermal Resource Areas Using A

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12, 2015Executive Order14,EnergyFinancing and Investing

  9. Finding Large Aperture Fractures in Geothermal Resource Areas Using a

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12, 2015Executive Order14,EnergyFinancing and InvestingThree-Component

  10. Status of the Silicon Photomultiplier Telescope FAMOUS for the Fluorescence Detection of UHECRs

    E-Print Network [OSTI]

    Niggemann, Tim; Brogueira, Pedro; Bueno, Antonio; Eichler, Hans Michael; Ferreira, Miguel; Hebbeker, Thomas; Lauscher, Markus; Mendes, Luís; Middendorf, Lukas; Navas, Sergio; Peters, Christine; Pimenta, Mário; Ruiz, Angel; Schumacher, Johannes; Stephan, Maurice

    2015-01-01

    An established technique for the measurement of ultra-high-energy-cosmic-rays is the detection of the fluorescence light induced in the atmosphere of the Earth, by means of telescopes equipped with photomultiplier tubes. Silicon photomultipliers (SiPMs) promise an increase in the photon detection efficiency which outperforms conventional photomultiplier tubes. In combination with their compact package, a moderate bias voltage of several ten volt and single photon resolution, the use of SiPMs can improve the energy and spatial resolution of air fluorescence measurements, and lead to a gain in information on the primary particle. Though, drawbacks like a high dark-noise-rate and a strong temperature dependency have to be managed. FAMOUS is a refracting telescope prototype instrumented with 64 SiPMs of which the main optical element is a Fresnel lens of 549.7 mm diameter and 502.1 mm focal length. The sensitive area of the SiPMs is increased by a special light collection system consisting of Winston cones. The t...

  11. Warm molecular Hydrogen at high redshift with the James Webb Space Telescope

    E-Print Network [OSTI]

    Guillard, P; Lehnert, M D; Appleton, P N; Forêts, G Pineau des

    2015-01-01

    The build-up of galaxies is regulated by a complex interplay between gravitational collapse, galaxy merging and feedback related to AGN and star formation. The energy released by these processes has to dissipate for gas to cool, condense, and form stars. How gas cools is thus a key to understand galaxy formation. \\textit{Spitzer Space Telescope} infrared spectroscopy revealed a population of galaxies with weak star formation and unusually powerful H$_2$ line emission. This is a signature of turbulent dissipation, sustained by large-scale mechanical energy injection. The cooling of the multiphase interstellar medium is associated with emission in the H$_2$ lines. These results have profound consequences on our understanding of regulation of star formation, feedback and energetics of galaxy formation in general. The fact that H$_2$ lines can be strongly enhanced in high-redshift turbulent galaxies will be of great importance for the \\textit{James Webb Space Telescope} observations which will unveil the role tha...

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

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    imaging between the east coast of Australia and South Africa at similar latitude. The Zadko Telescope in frontier optical transient science projects. The so called `transient Universe'' consists of astronomical image processing pipeline produces calibrated FITS images to external users via a web-based interface

  13. Contributions to free-space optical communications: feasibility of utilizing Cherenkov telescopes as receivers and beam-wander correction in quantum communications

    E-Print Network [OSTI]

    Carrasco-Casado, Alberto

    2015-01-01

    This thesis focuses on the two main applications where free-space optical communication (FSOC) can bring the most significant impact: interplanetary communications and quantum communications. Consequently, the dissertation is structured in two sections. In the first one, a novel proposal is suggested regarding to using Cherenkov telescopes as ground-station receivers. A feasibility study addresses the posibility of using the technology developed for the gamma-ray telescopes that will make up the Cherenkov Telescope Array (CTA) in the implementation of a new kind of ground station. Among the main advantages that these telescopes provide are the much larger apertures needed to overcome the power limitation that ground-based gamma-ray astronomy and deep-space optical communication both have. Also, the large number of big telescopes that will be built for CTA will make it possible to reduce unitary costs by economy-scale production. The second section of the thesis is framed in the field of free-space Quantum Key...

  14. Integrated modeling to facilitate control architecture design for lightweight space telescopes

    E-Print Network [OSTI]

    Cohan, Lucy Elizabeth

    2007-01-01

    The purpose of this thesis it to examine the effects of utilizing control to better meet performance and systematic requirements of future space telescopes. New telescope systems are moving toward tighter optical performance ...

  15. Tradespace Investigation of a Telescope Architecture for Next-generation Space Astronomy and Exploration

    E-Print Network [OSTI]

    Cataldo, Giuseppe

    2014-12-19

    Humanity’s endeavor to further its scientific understanding of the celestial heavens has led to the creation and evolution of increasingly powerful and complex space telescopes. Space telescopes provide a view of the solar ...

  16. THE NUCLEAR SPECTROSCOPIC TELESCOPE ARRAY (NuSTAR) HIGH-ENERGY...

    Office of Scientific and Technical Information (OSTI)

    NUCLEAR SPECTROSCOPIC TELESCOPE ARRAY (NuSTAR) HIGH-ENERGY X-RAY MISSION Citation Details In-Document Search Title: THE NUCLEAR SPECTROSCOPIC TELESCOPE ARRAY (NuSTAR) HIGH-ENERGY...

  17. The White Mountain Polarimeter Telescope and an Upper Limit on CMB Polarization

    E-Print Network [OSTI]

    Alan R. Levy; Rodrigo Leonardi; Markus Ansmann; Marco Bersanelli; Jeffery Childers; Terrence D. Cole; Ocleto D'Arcangelo; G. Vietor Davis; Philip M. Lubin; Joshua Marvil; Peter R. Meinhold; Gerald Miller; Hugh O`Neill; Fabrizio Stavola; Nathan C. Stebor; Peter T. Timbie; Maarten van der Heide; Fabrizio Villa; Thyrso Villela; Brian D. Williams; Carlos A. Wuensche

    2008-04-23

    The White Mountain Polarimeter (WMPol) is a dedicated ground-based microwave telescope and receiver system for observing polarization of the Cosmic Microwave Background. WMPol is located at an altitude of 3880 meters on a plateau in the White Mountains of Eastern California, USA, at the Barcroft Facility of the University of California White Mountain Research Station. Presented here is a description of the instrument and the data collected during April through October 2004. We set an upper limit on $E$-mode polarization of 14 $\\mu\\mathrm{K}$ (95% confidence limit) in the multipole range $170<\\ell<240$. This result was obtained with 422 hours of observations of a 3 $\\mathrm{deg}^2$ sky area about the North Celestial Pole, using a 42 GHz polarimeter. This upper limit is consistent with $EE$ polarization predicted from a standard $\\Lambda$-CDM concordance model.

  18. Detecting extended gamma-ray emission with the next generation Cherenkov telescopes

    E-Print Network [OSTI]

    Alonso, M Fernandez; Rovero, A C

    2015-01-01

    Very high energy (VHE $>$100 GeV) gamma rays coming from blazars can produce pairs when interacting with the Extragalactic Background Light (EBL) and the Cosmic Microwave Background, generating an electromagnetic cascade. Depending on the Intergalactic Magnetic Field (IGMF) intensity, this cascade may result in an extended isotropic emission of photons around the source (halo), or in a broadening of the emission beam. The detection of these effects might lead to important constrains both on the IGMF intensity and the EBL density, quantities of great relevance in cosmological models. Using a Monte Carlo program, we simulate electromagnetic cascades for different values of the IGMF intensities and coming from a source similar to 1ES0229+200, a blazar with hard intrinsic spectrum at redshift $z=0.14$, which is an ideal distance for potentially observing the effect. We study the possible response of a generic future Cherenkov telescope using a simplified model for the sensitivity, effective area and angular resol...

  19. An Efficient Work-Distribution Strategy for Gridding Radio-Telescope Data on GPUs

    E-Print Network [OSTI]

    Romein, John W.

    other telescopes in the world together -- the Square Kilometre Array (SKA) [4]. The imager is a critical

  20. Wildlife Management Areas (Florida)

    Broader source: Energy.gov [DOE]

    Certain sites in Florida are designated as wildlife management areas, and construction and development is heavily restricted in these areas.

  1. Early Optical Follow-up Observations of Gamma Ray Bursts with the Robotic Liverpool Telescope

    E-Print Network [OSTI]

    Gomboc, Andreja

    Early Optical Follow-up Observations of Gamma Ray Bursts with the Robotic Liverpool Telescope A, Slovenia 3 ITC-IRST and INFN, Trento, via Sommarive, 18 38050 Povo (TN), Italy Abstract Robotic telescopes of robotic telescopes is the rapid reaction to Targets of Opportunity, including short and unpredictable

  2. EarlyTime Observations of GRBs afterglow with 2m Robotic Telescopes

    E-Print Network [OSTI]

    Gomboc, Andreja

    Early­Time Observations of GRBs afterglow with 2­m Robotic Telescopes A. Melandri # , A. Gomboc time multi­wavelength light curves, obtained by space and ground­based robotic telescopes, have shown followup programme being conducted on a network of the world's three largest robotic telescopes that aims

  3. Cornelis Zwaan, open principle, and the future of high-resolution solar telescopes

    E-Print Network [OSTI]

    Rutten, Rob

    ; (iii) the design consequences for the new generation of high-resolution solar telescopes. Keywords to the open tower design. In section 3 we consider the interaction between the wind and the telescope 15 m and upward when there is some wind. The conclusion from this experience was the open telescope

  4. Management of the Gemini 8M Telescopes Project R. Kurz, M. Mountain

    E-Print Network [OSTI]

    Management of the Gemini 8­M Telescopes Project R. Kurz, M. Mountain Gemini Telescopes Project, 950 N. Cherry Ave., Tucson AZ 85719 Gemini Preprint #7 #12; Management of the Gemini 8­M Telescopes, organizations in the partner countries, and industrial contractors. The project organization and management

  5. A Wide-Field Infrared Camera for the Palomar 200-inch Telescope

    E-Print Network [OSTI]

    Galis, Frietson

    A Wide-Field Infrared Camera for the Palomar 200-inch Telescope J. C. Wilsona, S. S. Eikenberrya, C that provides the Palomar 200-inch telescope with such an imaging capability. WIRC features a field-of-view (FOV Camera (WIRC) at the Palomar 200-inch telescope. Mounted at prime focus to take advantage

  6. Transmission of light in deep sea water at the site of the Antares neutrino telescope

    E-Print Network [OSTI]

    ANTARES collaboration

    2004-12-06

    The ANTARES neutrino telescope is a large photomultiplier array designed to detect neutrino-induced upward-going muons by their Cherenkov radiation. Understanding the absorption and scattering of light in the deep Mediterranean is fundamental to optimising the design and performance of the detector. This paper presents measurements of blue and UV light transmission at the ANTARES site taken between 1997 and 2000. The derived values for the scattering length and the angular distribution of particulate scattering were found to be highly correlated, and results are therefore presented in terms of an absorption length lambda_abs and an effective scattering length lambda_sct^eff. The values for blue (UV) light are found to be lambda_abs ~ 60(26) m, lambda_sct^eff ~ 265(122) m, with significant (15%) time variability. Finally, the results of ANTARES simulations showing the effect of these water properties on the anticipated performance of the detector are presented.

  7. A Generic and Efficient E-field Parallel Imaging Correlator for Next-Generation Radio Telescopes

    E-Print Network [OSTI]

    Thyagarajan, Nithyanandan; Bowman, Judd D; Morales, Miguel F

    2015-01-01

    Modern radio telescopes are favoring densely packed array layouts consisting of large numbers of antennas ($N_\\textrm{a}\\gtrsim 1000$). Since the complexity of traditional correlators scales as $\\mathcal{O}(N_\\textrm{a}^2)$, there will be a steep cost for realizing the full imaging potential of these powerful instruments. Through our generic and efficient E-field Parallel Imaging Correlator (EPIC), we present the first software demonstration of a generalized direct imaging algorithm known as the Modular Optimal Frequency Fourier (MOFF) imager. It takes advantage of the multiplication-convolution theorem of Fourier transforms. Not only does it bring down the cost for dense layouts to $\\mathcal{O}(N_\\textrm{a}\\log_2 N_\\textrm{a})$ but can also image from irregularly arranged heterogeneous antenna arrays. EPIC is highly modular and parallelizable, implemented in object oriented Python, and publicly available. We have verified the images produced to be equivalent to those produced using traditional techniques. We...

  8. Direct measurement of the size of 2003 UB313 from the Hubble Space Telescope

    E-Print Network [OSTI]

    M. E. Brown; E. L. Schaller; H. G. Roe; D. L. Rabinowitz; C. A. Trujillo

    2006-04-11

    We have used the Hubble Space Telescope to directly measure the angular size of the large Kuiper belt object 2003 UB313. By carefully calibrating the point spread function of a nearby field star, we measure the size of 2003 UB313 to be 34.3$\\pm$1.4 milliarcseconds, corresponding to a diameter of 2400$\\pm$100 km or a size $\\sim5$% larger than Pluto. The V band geometric albedo of 2003 UB313 is $86\\pm7$%. The extremely high albedo is consistent with the frosty methane spectrum, the lack of red coloring, and the lack of observed photometric variation on the surface of 2003 UB313. Methane photolysis should quickly darken the surface of 2003 UB313, but continuous evaporation and redeposition of surface ices appears capable of maintaining the extreme alebdo of this body.

  9. Observation of GRBs by the MAGIC Telescope, Status and Outlook

    E-Print Network [OSTI]

    D. Bastieri; N. Galante; M. Garczarczyk; M. Gaug; F. Longo; S. Mizobuchi; V. Scapin

    2007-09-10

    Observation of Gamma Ray Bursts (GRBs) in the Very High Energy (VHE) domain will provide important information on the physical conditions in GRB outflows. The MAGIC telescope is the best suited Imaging Atmospheric Cherenkov Telescope (IACT) for these observations. Thanks to its fast repositioning time and low energy threshold, MAGIC is able to start quickly the follow-up observation, triggered by an alert from the GRB Coordinates Network (GCN), and observe the prompt emission and early afterglow phase from GRBs. In the last two years of operation several GRB follow-up observations were performed by MAGIC, however, until now without successful detection of VHE gamma rays above threshold energies >100 GeV. In this paper we revise the expectations for the GRB observations with MAGIC, based on the experience from the last years of operation.

  10. Registration of atmospheric neutrinos with the Baikal neutrino telescope

    E-Print Network [OSTI]

    Baikal Collaboration; V. A. Balkanov et al

    1999-03-23

    We present first neutrino induced events observed with a deep underwater neutrino telescope. Data from 70 days effective life time of the BAIKAL prototype telescope NT-96 have been analyzed with two different methods. With the standard track reconstruction method, 9 clear upward muon candidates have been identified, in good agreement with 8.7 events expected from Monte Carlo calculations for atmospheric neutrinos. The second analysis is tailored to muons coming from close to the opposite zenith. It yields 4 events, compared to 3.5 from Monte Carlo expectations. From this we derive a 90 % upper flux limit of 1.1 * 10^-13 cm^-2 sec^-1 for muons in excess of those expected from atmospheric neutrinos with zenith angle > 150 degrees and energy > 10GeV.

  11. SLAC All Access: Fermi Gamma-ray Space Telescope

    ScienceCinema (OSTI)

    Romani, Roger

    2014-06-24

    Three hundred and fifty miles overhead, the Fermi Gamma-ray Space Telescope silently glides through space. From this serene vantage point, the satellite's instruments watch the fiercest processes in the universe unfold. Pulsars spin up to 700 times a second, sweeping powerful beams of gamma-ray light through the cosmos. The hyperactive cores of distant galaxies spew bright jets of plasma. Far beyond, something mysterious explodes with unfathomable power, sending energy waves crashing through the universe. Stanford professor and KIPAC member Roger W. Romani talks about this orbiting telescope, the most advanced ever to view the sky in gamma rays, a form of light at the highest end of the energy spectrum that's created in the hottest regions of the universe.

  12. Laser metrology for coherent multi-telescope arrays

    DOE Patents [OSTI]

    Shao, M.; Massie, N.A.

    1993-05-04

    In multi-telescope arrays that comprise multiple telescopes, a beam-combining module, and flat mirrors for directing light beams from the multiple telescopes to the beam combining module, a laser metrology system is used for monitoring various pathlengths along a beam path where deviations are likely. Some pathlengths are defined simply by a pair of retroreflectors or reflectors at both ends. Lengths between pairs of retroreflectors are measured and monitored by laser interferometers. One critical pathlength deviation is related to the displacement of the flat mirror. A reference frame is set up relative to the beam-combining module to form and define the coordinate system within which the positions of the flat mirrors are measured and monitored. In the preferred embodiment, a pair of retroreflectors along the optical axis of the beam-combining module defines a reference frame. A triangle is formed by the reference frame as the base and another retroreflector at the flat mirror as the vertex. The triangle is used to monitor the position of the flat mirror. A beam's pathlength is dynamically corrected in response to the monitored deviations.

  13. Laser metrology for coherent multi-telescope arrays

    DOE Patents [OSTI]

    Shao, Michael (Pasadena, CA); Massie, Norbert A. (San Ramon, CA)

    1993-01-01

    In multi-telescope arrays that comprise multiple telescopes, a beam-combining module, and flat mirrors for directing light beams from the multiple telescopes to the beam combining module, a laser metrology system is used for monitoring various pathlengths along a beam path where deviations are likely. Some pathlengths are defined simply by a pair of retroreflectors or reflectors at both ends. Lengths between pairs of retroreflectors are measured and monitored by laser interferometers. One critical pathlength deviation is related to the displacement of the flat mirror. A reference frame is set up relative to the beam-combining module to form and define the coordinate system within which the positions of the flat mirrors are measured and monitored. In the preferred embodiment, a pair of retroreflectors along the optical axis of the beam-combining module defines a reference frame. A triangle is formed by the reference frame as the base and another retroreflector at the flat mirror as the vertex. The triangle is used to monitor the position of the flat mirror. A beam's pathlength is dynamically corrected in response to the monitored deviations.

  14. The Instrument Response Function Format for the Cherenkov Telescope Array

    E-Print Network [OSTI]

    Ward, John E

    2015-01-01

    The Cherenkov Telescope Array (CTA) is a future ground-based observatory (with two locations, in the Northern and Southern Hemispheres) that will be used in the study of the very-high-energy gamma-ray sky. CTA observations will be proposed by external users or initiated by the observatory, with the resulting measurements being processed by the CTA observatory and the reduced data made accessible to the corresponding proposer. Instrument Response Functions (IRFs) will also be provided to convert the quantities measured by the array(s) into relevant science products (i.e. spectra, sky maps, light curves). As the response of the telescopes depend on many correlated observational and physical quantities (e.g. gamma-ray arrival direction, energy, telescope orientation, background light, weather conditions etc.) the CTA IRFs could grow into increasingly larger and larger file sizes, which can become unwieldy or impractical for use in specific observation cases. To this end, a customized IRF format (complying with t...

  15. Sloan Digital Sky Survey photometric telescope automation and observing software

    SciTech Connect (OSTI)

    Eric H. Neilsen, Jr. et al.

    2002-10-16

    The photometric telescope (PT) provides observations necessary for the photometric calibration of the Sloan Digital Sky Survey (SDSS). Because the attention of the observing staff is occupied by the operation of the 2.5 meter telescope which takes the survey data proper, the PT must reliably take data with little supervision. In this paper we describe the PT's observing program, MOP, which automates most tasks necessary for observing. MOP's automated target selection is closely modeled on the actions a human observer might take, and is built upon a user interface that can be (and has been) used for manual operation. This results in an interface that makes it easy for an observer to track the activities of the automating procedures and intervene with minimum disturbance when necessary. MOP selects targets from the same list of standard star and calibration fields presented to the user, and chooses standard star fields covering ranges of airmass, color, and time necessary to monitor atmospheric extinction and produce a photometric solution. The software determines when additional standard star fields are unnecessary, and selects survey calibration fields according to availability and priority. Other automated features of MOP, such as maintaining the focus and keeping a night log, are also built around still functional manual interfaces, allowing the observer to be as active in observing as desired; MOP's automated features may be used as tools for manual observing, ignored entirely, or allowed to run the telescope with minimal supervision when taking routine data.

  16. INFN Camera demonstrator for the Cherenkov Telescope Array

    E-Print Network [OSTI]

    ,

    2015-01-01

    The Cherenkov Telescope Array is a world-wide project for a new generation of ground-based Cherenkov telescopes of the Imaging class with the aim of exploring the highest energy region of the electromagnetic spectrum. With two planned arrays, one for each hemisphere, it will guarantee a good sky coverage in the energy range from a few tens of GeV to hundreds of TeV, with improved angular resolution and a sensitivity in the TeV energy region better by one order of magnitude than the currently operating arrays. In order to cover this wide energy range, three different telescope types are envisaged, with different mirror sizes and focal plane features. In particular, for the highest energies a possible design is a dual-mirror Schwarzschild-Couder optical scheme, with a compact focal plane. A silicon photomultiplier (SiPM) based camera is being proposed as a solution to match the dimensions of the pixel (angular size of ~ 0.17 degrees). INFN is developing a camera demonstrator made by 9 Photo Sensor Modules (PSMs...

  17. Area Activation 1 Running Head: AREA ACTIVATION

    E-Print Network [OSTI]

    Pomplun, Marc

    Area Activation 1 Running Head: AREA ACTIVATION Advancing Area Activation towards a General Model at Boston 100 Morrissey Boulevard Boston, MA 02125-3393 USA Phone: 617-287-6485 Fax: 617-287-6433 e. Without great effort, human observers clearly outperform every current artificial vision system in tasks

  18. REVEALING THE PHYSICAL PROPERTIES OF MOLECULAR GAS IN ORION WITH A LARGE-SCALE SURVEY IN J = 2-1 LINES OF {sup 12}CO, {sup 13}CO, AND C{sup 18}O

    SciTech Connect (OSTI)

    Nishimura, Atsushi; Tokuda, Kazuki; Kimura, Kimihiro; Muraoka, Kazuyuki; Maezawa, Hiroyuki; Ogawa, Hideo; Onishi, Toshikazu [Department of Physical Science, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531 (Japan); Dobashi, Kazuhito; Shimoikura, Tomomi [Department of Astronomy and Earth Sciences, Tokyo Gakugei University, 4-1-1 Nukuikita-machi, Koganei, Tokyo 184-8501 (Japan); Mizuno, Akira [Solar-terrestrial Environment Laboratory, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601 (Japan); Fukui, Yasuo, E-mail: atsushi.nishimura@nao.ac.jp [Department of Physics and Astrophysics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602 (Japan)

    2015-01-01

    We present fully sampled ?3' resolution images of {sup 12}CO(J = 2-1), {sup 13}CO(J = 2-1), and C{sup 18}O(J = 2-1) emission taken with the newly developed 1.85 m millimeter-submillimeter telescope over the entire area of the Orion A and B giant molecular clouds. The data were compared with J = 1-0 of the {sup 12}CO, {sup 13}CO, and C{sup 18}O data taken with the Nagoya 4 m telescope and the NANTEN telescope at the same angular resolution to derive the spatial distributions of the physical properties of the molecular gas. We explore the large velocity gradient formalism to determine the gas density and temperature using line combinations of {sup 12}CO(J = 2-1), {sup 13}CO(J = 2-1), and {sup 13}CO(J = 1-0) assuming a uniform velocity gradient and abundance ratio of CO. The derived gas density is in the range of 500 to 5000 cm{sup –3}, and the derived gas temperature is mostly in the range of 20 to 50 K along the cloud ridge with a temperature gradient depending on the distance from the star forming region. We found that the high-temperature region at the cloud edge faces the H II region, indicating that the molecular gas is interacting with the stellar wind and radiation from the massive stars. In addition, we compared the derived gas properties with the young stellar objects distribution obtained with the Spitzer telescope to investigate the relationship between the gas properties and the star formation activity therein. We found that the gas density and star formation efficiency are positively well correlated, indicating that stars form effectively in the dense gas region.

  19. Edge Detection, Cosmic Strings and the South Pole Telescope

    E-Print Network [OSTI]

    Andrew Stewart; Robert Brandenberger

    2009-01-07

    We develop a method of constraining the cosmic string tension $G\\mu$ which uses the Canny edge detection algorithm as a means of searching CMB temperature maps for the signature of the Kaiser-Stebbins effect. We test the potential of this method using high resolution, simulated CMB temperature maps. By modeling the future output from the South Pole Telescope project (including anticipated instrumental noise), we find that cosmic strings with $G\\mu > 5.5\\times10^{-8}$ could be detected.

  20. Design study of an air-Cherenkov telescope for harsh environments with efficient air-shower detection at 100 TeV

    E-Print Network [OSTI]

    Auffenberg, Jan; Middendorf, Lukas; Niggemann, Tim; Rädel, Leif; Schaufel, Merlin; Schoenen, Sebastian; Schumacher, Johannes; Wiebusch, Christopher

    2015-01-01

    Telescopes, designed with semi-conductor based photo sensors, have the potential to detect Cherenkov or fluorescence light emitted by cosmic-rays in the atmosphere. Such telescopes promise a high duty cycle and efficiency in remote harsh environments. Given the relatively low costs and robustness of these instruments, this technology could prove interesting especially if deployed in large numbers with existing and future extended cosmic-ray and gamma ray detectors, including the Pierre Auger observatory, HAWC, IceCube and CTA. They may have the potential to enhance the sensitivity of these instruments for the detection of high-energy gamma rays and cosmic-ray air showers. In addition, for neutrino telescopes such a technology could prove to be an efficient cosmic-ray veto on the surface. In this contribution the current motivation, design, and development of a prototype SiPM based air Cherenkov telescope is described. The results of initial sensitivity studies, and the readiness of the system for first tests,...

  1. Sites in Argentina for the Cherenkov Telescope Array Project

    E-Print Network [OSTI]

    Allekotte, Ingo; Etchegoyen, Alberto; García, Beatriz; Mancilla, Alexis; Maya, Javier; Ravignani, Diego; Rovero, Adrián

    2013-01-01

    The Cherenkov Telescope Array (CTA) Project will consist of two arrays of atmospheric Cherenkov telescopes to study high-energy gamma radiation in the range of a few tens of GeV to beyond 100 TeV. To achieve full-sky coverage, the construction of one array in each terrestrial hemisphere is considered. Suitable candidate sites are being explored and characterized. The candidate sites in the Southern Hemisphere include two locations in Argentina, one in San Antonio de los Cobres (Salta Province, Lat. 24:02:42 S, Long. 66:14:06 W, at 3600 m.a.s.l) and another one in El Leoncito (San Juan Province, Lat. 31:41:49 S, Long. 69:16:21 W, at 2600 m.a.s.l). Here we describe the two sites and the instrumentation that has been deployed to characterize them. We summarize the geographic, atmospheric and climatic data that have been collected for both of them.

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

    E-Print Network [OSTI]

    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...

  3. Strong gravitational lensing of gravitational waves in Einstein Telescope

    SciTech Connect (OSTI)

    Piórkowska, Aleksandra; Biesiada, Marek [Department of Astrophysics and Cosmology, Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland); Zhu, Zong-Hong, E-mail: aleksandra.piorkowska@us.edu.pl, E-mail: marek.biesiada@us.edu.pl, E-mail: zhuzh@bnu.edu.cn [Department of Astronomy, Beijing Normal University, Beijing 100875 (China)

    2013-10-01

    Gravitational wave experiments have entered a new stage which gets us closer to the opening a new observational window on the Universe. In particular, the Einstein Telescope (ET) is designed to have a fantastic sensitivity that will provide with tens or hundreds of thousand NS-NS inspiral events per year up to the redshift z = 2. Some of such events should be gravitationally lensed by intervening galaxies. We explore the prospects of observing gravitationally lensed inspiral NS-NS events in the Einstein telescope. Being conservative we consider the lens population of elliptical galaxies. It turns out that depending on the local insipral rate ET should detect from one per decade detection in the pessimistic case to a tens of detections per year for the most optimistic case. The detection of gravitationally lensed source in gravitational wave detectors would be an invaluable source of information concerning cosmography, complementary to standard ones (like supernovae or BAO) independent of the local cosmic distance ladder calibrations.

  4. The On-Site Analysis of the Cherenkov Telescope Array

    E-Print Network [OSTI]

    Bulgarelli, Andrea; Zoli, Andrea; Aboudan, Alessio; Rodríguez-Vázquez, Juan José; De Cesare, Giovanni; De Rosa, Adriano; Maier, Gernot; Lyard, Etienne; Bastieri, Denis; Lombardi, Saverio; Tosti, Gino; Bergamaschi, Sonia; Beneventano, Domenico; Lamanna, Giovanni; Jacquemier, Jean; Kosack, Karl; Antonelli, Lucio Angelo; Boisson, Catherine; Borkowski, Jerzy; Buson, Sara; Carosi, Alessandro; Conforti, Vito; Colomé, Pep; Reyes, Raquel de los; Dumm, Jon; Evans, Phil; Fortson, Lucy; Fuessling, Matthias; Gotz, Diego; Graciani, Ricardo; Gianotti, Fulvio; Grandi, Paola; Hinton, Jim; Humensky, Brian; Inoue, Susumu; Knödlseder, Jürgen; Flour, Thierry Le; Lindemann, Rico; Malaguti, Giuseppe; Markoff, Sera; Marisaldi, Martino; Neyroud, Nadine; Nicastro, Luciano; Ohm, Stefan; Osborne, Julian; Oya, Igor; Rodriguez, Jerome; Rosen, Simon; Ribo, Marc; Tacchini, Alessandro; Schüssler, Fabian; Stolarczyk, Thierry; Torresi, Eleonora; Testa, Vincenzo; Wegner, Peter

    2015-01-01

    The Cherenkov Telescope Array (CTA) observatory will be one of the largest ground-based very high-energy gamma-ray observatories. The On-Site Analysis will be the first CTA scientific analysis of data acquired from the array of telescopes, in both northern and southern sites. The On-Site Analysis will have two pipelines: the Level-A pipeline (also known as Real-Time Analysis, RTA) and the level-B one. The RTA performs data quality monitoring and must be able to issue automated alerts on variable and transient astrophysical sources within 30 seconds from the last acquired Cherenkov event that contributes to the alert, with a sensitivity not worse than the one achieved by the final pipeline by more than a factor of 3. The Level-B Analysis has a better sensitivity (not be worse than the final one by a factor of 2) and the results should be available within 10 hours from the acquisition of the data: for this reason this analysis could be performed at the end of an observation or next morning. The latency (in part...

  5. A Cryogenic Space Telescope for Far-Infrared Astrophysics: A Vision for NASA in the 2020 Decade

    E-Print Network [OSTI]

    Bradford, C M; Bolatto, A; Armus, L; Bauer, J; Appleton, P; Cooray, A; Casey, C; Dale, D; Uzgil, B; Aguirre, J; Smith, J D; Sheth, K; Murphy, E J; McKenney, C; Holmes, W; Rizzo, M; Bergin, E; Stacey, G

    2015-01-01

    Many of the transformative processes in the Universe have taken place in regions obscured by dust, and are best studied with far-IR spectroscopy. We present the Cryogenic-Aperture Large Infrared-Submillimeter Telescope Observatory (CALISTO), a 5-meter class, space-borne telescope actively cooled to 4 K, emphasizing moderate-resolution spectroscopy in the crucial 35 to 600 micron band. CALISTO will enable NASA and the world to study the rise of heavy elements in the Universe's first billion years, chart star formation and black hole growth in dust-obscured galaxies through cosmic time, and conduct a census of forming planetary systems in our region of the Galaxy. CALISTO will capitalize on rapid progress in both format and sensitivity of far-IR detectors. Arrays with a total count of a few 100,000 detector pixels will form the heart of a suite of imaging spectrometers in which each detector reaches the photon background limit. This document contains a large overview paper on CALISTO, as well as six 2-3 page sc...

  6. Deployable telescope having a thin-film mirror and metering structure

    DOE Patents [OSTI]

    Krumel, Leslie J. (Cedar Crest, NM); Martin, Jeffrey W. (Albuquerque, NM)

    2010-08-24

    A deployable thin-film mirror telescope comprises a base structure and a metering structure. The base structure houses a thin-film mirror, which can be rolled for stowage and unrolled for deployment. The metering structure is coupled to the base structure and can be folded for stowage and unfolded for deployment. In the deployed state, the unrolled thin-film mirror forms a primary minor for the telescope and the unfolded metering structure positions a secondary minor for the telescope.

  7. Large displacement spherical joint

    DOE Patents [OSTI]

    Bieg, Lothar F. (Albuquerque, NM); Benavides, Gilbert L. (Albuquerque, NM)

    2002-01-01

    A new class of spherical joints has a very large accessible full cone angle, a property which is beneficial for a wide range of applications. Despite the large cone angles, these joints move freely without singularities.

  8. Observation of solar flares through the ART-P telescope side shield

    E-Print Network [OSTI]

    A. Lutovinov; M. Pavlinsky; S. Grebenev

    2001-06-13

    Some preliminary results of observations of six solar flares though the ART-P telescop side shield in 1990-1992 are presented.

  9. Measurement of the Cosmic Microwave Background Polarization with the BICEP Telescope at the South Pole

    E-Print Network [OSTI]

    Takahashi, Yuki David

    2010-01-01

    South Pole Dark Sector and LC-130 . . . . . . .2.2 South Pole site . . . . . . . . . . . . . .Bicep Telescope at the South Pole by Yuki David Takahashi A

  10. Dense molecular clumps associated with the Large Magellanic Cloud supergiant shells LMC 4 and LMC 5

    SciTech Connect (OSTI)

    Fujii, Kosuke; Mizuno, Norikazu [Department of Astronomy, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 133-0033 (Japan); Minamidani, Tetsuhiro [Nobeyama Radio Observatory, 462-2 Nobeyama Minamimaki-mura, Minamisaku-gun, Nagano 384-1305 (Japan); Onishi, Toshikazu; Muraoka, Kazuyuki [Department of Physical Science, Osaka Prefecture University, Gakuen 1-1, Sakai, Osaka 599-8531 (Japan); Kawamura, Akiko; Muller, Erik; Tatematsu, Ken'ichi; Hasegawa, Tetsuo; Miura, Rie E.; Ezawa, Hajime [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Dawson, Joanne [Australia Telescope National Facility, CSIRO Astronomy and Space Science, P.O. Box 76, Epping, NSW 1710 (Australia); Tosaki, Tomoka [Joetsu University of Education, Yamayashiki-machi, Joetsu, Niigata 943-8512 (Japan); Sakai, Takeshi [Graduate School of Informatics and Engineering, The University of Electro-Communications, Chofu, Tokyo 182-8585 (Japan); Tsukagoshi, Takashi [College of Science, Ibaraki University, Bunkyo 2-1-1, Mito 310-8512 (Japan); Tanaka, Kunihiko [Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Yokohama, Kanagawa 223-8522 (Japan); Fukui, Yasuo, E-mail: kosuke.fujii@nao.ac.jp [Department of Astrophysics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan)

    2014-12-01

    We investigate the effects of supergiant shells (SGSs) and their interaction on dense molecular clumps by observing the Large Magellanic Cloud (LMC) star-forming regions N48 and N49, which are located between two SGSs, LMC 4 and LMC 5. {sup 12}CO (J = 3-2, 1-0) and {sup 13}CO(J = 1-0) observations with the ASTE and Mopra telescopes have been carried out toward these regions. A clumpy distribution of dense molecular clumps is revealed with 7 pc spatial resolution. Large velocity gradient analysis shows that the molecular hydrogen densities (n(H{sub 2})) of the clumps are distributed from low to high density (10{sup 3}-10{sup 5} cm{sup –3}) and their kinetic temperatures (T {sub kin}) are typically high (greater than 50 K). These clumps seem to be in the early stages of star formation, as also indicated from the distribution of H?, young stellar object candidates, and IR emission. We found that the N48 region is located in the high column density H I envelope at the interface of the two SGSs and the star formation is relatively evolved, whereas the N49 region is associated with LMC 5 alone and the star formation is quiet. The clumps in the N48 region typically show high n(H{sub 2}) and T {sub kin}, which are as dense and warm as the clumps in LMC massive cluster-forming areas (30 Dor, N159). These results suggest that the large-scale structure of the SGSs, especially the interaction of two SGSs, works efficiently on the formation of dense molecular clumps and stars.

  11. Data model issues in the Cherenkov Telescope Array project

    E-Print Network [OSTI]

    Contreras, J L; Bernlöhr, K; Boisson, C; Bregeon, J; Bulgarelli, A; de Cesare, G; Reyes, R de los; Fioretti, V; Kosack, K; Lavalley, C; Lyard, E; Marx, R; Rico, J; Sanguillot, M; Servillat, M; Walter, R; Ward, J E

    2015-01-01

    The planned Cherenkov Telescope Array (CTA), a future ground-based Very-High-Energy (VHE) gamma-ray observatory, will be the largest project of its kind. It aims to provide an order of magnitude increase in sensitivity compared to currently operating VHE experiments and open access to guest observers. These features, together with the thirty years lifetime planned for the installation, impose severe constraints on the data model currently being developed for the project. In this contribution we analyze the challenges faced by the CTA data model development and present the requirements imposed to face them. While the full data model is still not completed we show the organization of the work, status of the design, and an overview of the prototyping efforts carried out so far. We also show examples of specific aspects of the data model currently under development.

  12. Data compression for the First G-APD Cherenkov Telescope

    E-Print Network [OSTI]

    Ahnen, M L; Bergmann, M; Biland, A; Bretz, T; Buß, J; Dorner, D; Einecke, S; Freiwald, J; Hempfling, C; Hildebrand, D; Hughes, G; Lustermann, W; Lyard, E; Mannheim, K; Meier, K; Mueller, S; Neise, D; Neronov, A; Overkemping, A -K; Paravac, A; Pauss, F; Rhode, W; Steinbring, T; Temme, F; Thaele, J; Toscano, S; Vogler, P; Walter, R; Wilbert, A

    2015-01-01

    The First Geiger-mode Avalanche photodiode (G-APD) Cherenkov Telescope (FACT) has been operating on the Canary island of La Palma since October 2011. Operations were automated so that the system can be operated remotely. Manual interaction is required only when the observation schedule is modified due to weather conditions or in case of unexpected events such as a mechanical failure. Automatic operations enabled high data taking efficiency, which resulted in up to two terabytes of FITS files being recorded nightly and transferred from La Palma to the FACT archive at ISDC in Switzerland. Since long term storage of hundreds of terabytes of observations data is costly, data compression is mandatory. This paper discusses the design choices that were made to increase the compression ratio and speed of writing of the data with respect to existing compression algorithms. Following a more detailed motivation, the FACT compression algorithm along with the associated I/O layer is discussed. Eventually, the performances...

  13. Methods for point source analysis in high energy neutrino telescopes

    E-Print Network [OSTI]

    Jim Braun; Jon Dumm; Francesco De Palma; Chad Finley; Albrecht Karle; Teresa Montaruli

    2008-01-10

    Neutrino telescopes are moving steadily toward the goal of detecting astrophysical neutrinos from the most powerful galactic and extragalactic sources. Here we describe analysis methods to search for high energy point-like neutrino sources using detectors deep in the ice or sea. We simulate an ideal cubic kilometer detector based on real world performance of existing detectors such as AMANDA, IceCube, and ANTARES. An unbinned likelihood ratio method is applied, making use of the point spread function and energy distribution of simulated neutrino signal events to separate them from the background of atmospheric neutrinos produced by cosmic ray showers. The unbinned point source analyses are shown to perform better than binned searches and, depending on the source spectral index, the use of energy information is shown to improve discovery potential by almost a factor of two.

  14. Infrared and visual lunar occultations measurements of stellar diameters and new binary stars detections at the Calar Alto 1.5m telescope

    E-Print Network [OSTI]

    O. Fors; A. Richichi; J. Nunez; A. Prades

    2004-02-03

    We present a program of routine lunar occultations, at optical and near-IR wavelengths, recently started at the 1.5m Spanish telescope at the Calar Alto Observatory. Both a CCD and an infrared array detector are used. The program is aimed mainly at the detection and investigation of binary systems, although results in other areas of stellar research are also anticipated. Occultations are reported for a total of 40 stars. Among these, SAO 164567, SAO 78258 and AG+24 788 have been discovered to be binaries, with projected separations as small as 0.006". Furthermore, binarity is suspected in the case of SAO 78119 and SAO 79251. Additionally, the angular diameter of the late-type giant 30 Psc and of the infrared star V349 Gem have been accurately measured, this latter for the first time. We finally evaluate the instrumentation performance in terms of limiting magnitude and angular resolution, and discuss applications to larger telescopes.

  15. Unit 51 - GIS Application Areas

    E-Print Network [OSTI]

    Unit 51, CC in GIS; Cowen, David; Ferguson, Warren

    1990-01-01

    51 - GIS APPLICATION AREAS UNIT 51 - GIS APPLICATION AREAS1990 Page 1 Unit 51 - GIS Application Areas Computers inyour students. UNIT 51 - GIS APPLICATION AREAS Compiled with

  16. Large-scale magnetic field of the G8 dwarf xi Bootis A

    E-Print Network [OSTI]

    P. Petit; J. -F. Donati; M. Auriere; J. D. Landstreet; F. Lignieres; S. Marsden; D. Mouillet; F. Paletou; N. Toque; G. A. Wade

    2005-05-20

    We investigate the magnetic geometry of the active G8 dwarf xi Bootis A, from spectropolarimetric observations obtained in 2003 with the MuSiCoS echelle spectropolarimeter at the Telescope Bernard Lyot (Observatoire du Pic du Midi, France). We repeatedly detect a photospheric magnetic field, with periodic variations consistent with rotational modulation. Circularly polarized (Stokes V) line profiles present a systematic asymmetry, showing up as an excess in amplitude and area of the blue lobe of the profiles. A direct modeling of Stokes V profiles suggests that the global magnetic field is composed of two main components, with an inclined dipole and a large-scale toroidal field. We derive a dipole intensity of about 40 G, with an inclination of 35 degrees of the dipole with respect to the rotation axis. The toroidal field strength is of order of 120 G. A noticeable evolution of the field geometry is observed over the 40 nights of our observing window and results in an increase of the field strength and of the dipole inclination. This study is the first step of a long-term monitoring of xi Bootis A and other active solar-type stars, with the aim to investigate secular fluctuations of stellar magnetic geometries induced by activity cycles.

  17. Active Optics Performance Study of the Primary Mirror of the Gemini Telescopes Project

    E-Print Network [OSTI]

    Active Optics Performance Study of the Primary Mirror of the Gemini Telescopes Project Myung K. Cho Optical Sciences Center in the University of Arizona Tucson, AZ 85721 and Gemini Telescopes Project P. O. Box 26732 Tucson, AZ 85726­6732 Gemini Preprint #9 #12; Active optics performance study of the primary

  18. Hopkins Ultraviolet Telescope Observations of Nova Circini 1995 and Nova Aquilae 1995

    E-Print Network [OSTI]

    Hopkins Ultraviolet Telescope Observations of Nova Circini 1995 and Nova Aquilae 1995 Bradford W 1995 and Nova Aql 1995 with the Hopkins Ultraviolet Telescope during the Astro­2 space shuttle mission in 1995 March. The spectra cover the wavelength range from 820 š A to 1840 š A with a spectral resolution

  19. End-to-end absolute energy calibration of atmospheric fluorescence telescopes by an electron linear accelerator

    E-Print Network [OSTI]

    End-to-end absolute energy calibration of atmospheric fluorescence telescopes by an electron linear of fluorescence telescopes by using air showers induced by electron beams from a linear accelerator, which and constructing a compact linear accelerator with a maximum electron energy of 40 MeV and an intensity of 6.4 m

  20. THE NUCLEAR SPECTROSCOPIC TELESCOPE ARRAY (NuSTAR) HIGH-ENERGY X-RAY MISSION

    E-Print Network [OSTI]

    Chakrabarty, Deepto

    The Nuclear Spectroscopic Telescope Array (NuSTAR) mission, launched on 2012 June 13, is the first focusing high-energy X-ray telescope in orbit. NuSTAR operates in the band from 3 to 79 keV, extending the sensitivity of ...

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

    E-Print Network [OSTI]

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

    2009-03-16

    The Taiwanese-American Occultation Survey (TAOS) operates four fully automatic telescopes to search for occultations of stars by Kuiper Belt Objects. It is a versatile facility that is also useful for the study of initial optical GRB afterglows. This paper provides a detailed description of the TAOS multi-telescope system, control software, and high-speed imaging.

  2. Multilayer coating facility for the HEFT hard X-ray telescope Carsten P. Jensena

    E-Print Network [OSTI]

    . Christensena , Hubert Chenb , Erik B. W.Smitta , Eric Zieglerc a Danish Space Research Institute (Denmark); b) for the production coating of depth graded multilayers on the thermally slumped glass segments which form the basis, Hard X-ray telescope 1. INTRODUCTION The High Energy Focusing Telescope (HEFT) is a balloon borne

  3. IL NUOVO CIMENTO Vol. ?, N. ? ? The Liverpool Telescope Automatic Pipeline for Realtime GRB

    E-Print Network [OSTI]

    Gomboc, Andreja

    IL NUOVO CIMENTO Vol. ?, N. ? ? The Liverpool Telescope Automatic Pipeline for Real­time GRB pipeline. PACS 95.55.Cs -- Ground­based ultraviolet, optical and infrared telescopes. PACS 95.75.Mn of the system is the subsequent pipelined data reduction, analysis and automatic identification of possible GRB

  4. Running Large Scale Jobs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    try on their large scale applications on Hopper for better performance. Try different compilers and compiler options The available compilers on Hopper are PGI, Cray, Intel, GNU,...

  5. ESO VERY LARGE TELESCOPE OPTICAL SPECTROSCOPY OF BL LACERTAE OBJECTS. IV. NEW SPECTRA AND PROPERTIES OF THE FULL SAMPLE

    SciTech Connect (OSTI)

    Landoni, M.; Treves, A.; Barattini, M.; Falomo, R.; Sbarufatti, B.; Decarli, R.; Kotilainen, J.

    2013-04-15

    We present the last chapter of a spectroscopy program aimed at deriving the redshift or a lower limit to the redshift of BL Lac objects using medium-resolution spectroscopy. Here we report new spectra for 33 BL Lac object candidates obtained in 2008-2009, confirming the BL Lac nature of 25 sources and obtaining new redshifts for 5 objects. These new observations are combined with our previous data in order to construct a homogeneous sample of {approx}70 BL Lac objects with high-quality spectroscopy. All these spectra can be accessed at the Web site http://www.oapd.inaf.it/zbllac/. The average spectrum, beaming properties of the full sample, discussion of intervening systems, and future perspectives are addressed.

  6. THE GREEN BANK TELESCOPE MAPS THE DENSE, STAR-FORMING GAS IN THE NEARBY STARBURST GALAXY M82

    SciTech Connect (OSTI)

    Kepley, Amanda A.; Frayer, David [National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944-0002 (United States); Leroy, Adam K. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903-2475 (United States); Usero, Antonio [Observatorio Astronómico Nacional, C/Alfonso XII, 3, E-28014 Madrid (Spain); Marvil, Josh [Department of Physics, New Mexico Tech., 801 Leroy Place, Socorro, NM 87801 (United States); Walter, Fabian, E-mail: akepley@nrao.edu [Max Planck Institute fur Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany)

    2014-01-01

    Observations of the Milky Way and nearby galaxies show that dense molecular gas correlates with recent star formation, suggesting that the formation of this gas phase may help regulate star formation. A key test of this idea requires wide-area, high-resolution maps of dense molecular gas in galaxies to explore how local physical conditions drive dense gas formation, but these observations have been limited because of the faintness of dense gas tracers like HCN and HCO{sup +}. Here we demonstrate the power of the Robert C. Byrd Green Bank Telescope (GBT)—the largest single-dish millimeter radio telescope—for mapping dense gas in galaxies by presenting the most sensitive maps yet of HCN and HCO{sup +} in the starburst galaxy M82. The HCN and HCO{sup +} in the disk of this galaxy correlates with both recent star formation and more diffuse molecular gas and shows kinematics consistent with a rotating torus. The HCO{sup +} emission extending to the north and south of the disk is coincident with the outflow previously identified in CO and traces the eastern edge of the hot outflowing gas. The central starburst region has a higher ratio of star formation to dense gas than the outer regions, pointing to the starburst as a key driver of this relationship. These results establish that the GBT can efficiently map the dense molecular gas at 90 GHz in nearby galaxies, a capability that will increase further with the 16 element feed array under construction.

  7. CMS Pixel Telescope Addition to T-980 Bent Crystal Collimation Experiment at the Tevatron

    E-Print Network [OSTI]

    Rivera, Ryan; Johnson, Todd; Kwan, Simon; Lundberg, Carl; Still, Dean; Prosser, Alan; Uplegger, Lorenzo; Zagel, Jim; Zvodaya, Viktoriya

    2012-01-01

    An enhancement to the T-980 bent crystal collimation experiment at the Tevatron has been completed. The enhancement was the installation of a pixel telescope inside the vacuum-sealed beam pipe of the Tevatron. The telescope is comprised of six CMS PSI46 pixel plaquettes, arranged as three stations of horizontal and vertical planes, with the CAPTAN system for data acquisition and control. The purpose of the pixel telescope is to measure beam profiles produced by bent crystals under various conditions. The telescope electronics inside the beam pipe initially were not adequately shielded from the image current of the passing beams. A new shielding approach was devised and installed, which resolved the problem. The noise issues encountered and the mitigating techniques are presented herein, as well as some preliminary results from the telescope.

  8. CMS Pixel Telescope Addition to T-980 Bent Crystal Collimation Experiment at the Tevatron

    SciTech Connect (OSTI)

    Rivera, Ryan; Annala, Jerry; Johnson, Todd; Kwan, Simon; Lundberg, Carl; Still, Dean; Prosser, Alan; Uplegger, Lorenzo; Zagel, Jim; Zvodaya, Viktoriya; /Fermilab

    2011-09-14

    An enhancement to the T-980 bent crystal collimation experiment at the Tevatron has been completed. The enhancement was the installation of a pixel telescope inside the vacuum-sealed beam pipe of the Tevatron. The telescope is comprised of six CMS PSI46 pixel plaquettes, arranged as three stations of horizontal and vertical planes, with the CAPTAN system for data acquisition and control. The purpose of the pixel telescope is to measure beam profiles produced by bent crystals under various conditions. The telescope electronics inside the beam pipe initially were not adequately shielded from the image current of the passing beams. A new shielding approach was devised and installed, which resolved the problem. The noise issues encountered and the mitigating techniques are presented herein, as well as some preliminary results from the telescope.

  9. The MAGIC Telescope Project for Gamma Astronomy above 10 GeV

    E-Print Network [OSTI]

    N. Magnussen

    1998-05-14

    A project to construct a 17 m diameter imaging air Cherenkov telescope, called the MAGIC Telescope, is described. The aim of the project is to close the observation gap in the gamma-ray sky extending from 10 GeV as the highest energy measurable by space-borne experiments to 300 GeV, the lowest energy measurable by the current generation of ground-based Cherenkov telescopes. The MAGIC Telescope will incorporate several new features in order to reach the very low energy threshold. At the same time the new technology will yield an improvement in sensitivity in the energy region where current Cherenkov telescopes are measuring by about an order of magnitude.

  10. A NEW APPROACH TO IDENTIFYING THE MOST POWERFUL GRAVITATIONAL LENSING TELESCOPES

    SciTech Connect (OSTI)

    Wong, Kenneth C.; Zabludoff, Ann I.; Ammons, S. Mark; Keeton, Charles R.; Hogg, David W.; Gonzalez, Anthony H.

    2013-05-20

    The best gravitational lenses for detecting distant galaxies are those with the largest mass concentrations and the most advantageous configurations of that mass along the line of sight. Our new method for finding such gravitational telescopes uses optical data to identify projected concentrations of luminous red galaxies (LRGs). LRGs are biased tracers of the underlying mass distribution, so lines of sight with the highest total luminosity in LRGs are likely to contain the largest total mass. We apply this selection technique to the Sloan Digital Sky Survey and identify the 200 fields with the highest total LRG luminosities projected within a 3.'5 radius over the redshift range 0.1 {<=} z {<=} 0.7. The redshift and angular distributions of LRGs in these fields trace the concentrations of non-LRG galaxies. These fields are diverse; 22.5% contain one known galaxy cluster and 56.0% contain multiple known clusters previously identified in the literature. Thus, our results confirm that these LRGs trace massive structures and that our selection technique identifies fields with large total masses. These fields contain two to three times higher total LRG luminosities than most known strong-lensing clusters and will be among the best gravitational lensing fields for the purpose of detecting the highest redshift galaxies.

  11. Testing the Bimodal/Schizophrenic Neutrino Hypothesis in Neutrinoless Double Beta Decay and Neutrino Telescopes

    E-Print Network [OSTI]

    James Barry; Rabindra N. Mohapatra; Werner Rodejohann

    2011-06-27

    The standard assumption is that all three neutrino mass states are either Dirac or Majorana. However, it was recently suggested by Allaverdi, Dutta and one of the authors (R.N.M.) that mixed, or bimodal, flavor neutrino scenarios are conceivable and are consistent with all known observations (these were called "schizophrenic" in the ADM paper). In that case each individual mass eigenstate can be either Dirac or Majorana, so that the flavor eigenstates are "large" admixtures of both. An example of this "bimodal" situation is to consider one mass state as a Dirac particle (with a sterile partner), while the other two are of Majorana type. Since only Majorana particles contribute to neutrinoless double beta decay, the usual dependence of this observable on the neutrino mass is modified within this scenario. We study this in detail and, in particular, generalize the idea for all possible bimodal combinations. Inevitably, radiative corrections will induce a pseudo-Dirac nature to the Dirac states at the one-loop level, and the effects of the pseudo-Dirac mass splitting will show up in the flavor ratios of neutrinos from distant cosmological sources. Comparison of the effective mass in neutrinoless double beta decay as well as flavor ratios at neutrino telescopes, for different pseudo-Dirac cases and with their usual phenomenology, can distinguish the different bimodal possibilities.

  12. OPTICAL PROPER MOTION MEASUREMENTS OF THE M87 JET: NEW RESULTS FROM THE HUBBLE SPACE TELESCOPE

    SciTech Connect (OSTI)

    Meyer, Eileen T.; Sparks, W. B.; Biretta, J. A.; Anderson, Jay; Sohn, Sangmo Tony; Van der Marel, Roeland P.; Norman, Colin; Nakamura, Masanori

    2013-09-10

    We report new results from a Hubble Space Telescope archival program to study proper motions in the optical jet of the nearby radio galaxy M87. Using over 13 yr of archival imaging, we reach accuracies below 0.1c in measuring the apparent velocities of individual knots in the jet. We confirm previous findings of speeds up to 4.5c in the inner 6'' of the jet, and report new speeds for optical components in the outer part of the jet. We find evidence of significant motion transverse to the jet axis on the order of 0.6c in the inner jet features, and superluminal velocities parallel and transverse to the jet in the outer knot components, with an apparent ordering of velocity vectors possibly consistent with a helical jet pattern. Previous results suggested a global deceleration over the length of the jet in the form of decreasing maximum speeds of knot components from HST-1 outward, but our results suggest that superluminal speeds persist out to knot C, with large differentials in very nearby features all along the jet. We find significant apparent accelerations in directions parallel and transverse to the jet axis, along with evidence for stationary features in knots D, E, and I. These results are expected to place important constraints on detailed models of kiloparsec-scale relativistic jets.

  13. DETECTION OF SMALL-SCALE GRANULAR STRUCTURES IN THE QUIET SUN WITH THE NEW SOLAR TELESCOPE

    SciTech Connect (OSTI)

    Abramenko, V. I.; Yurchyshyn, V. B.; Goode, P. R.; Kitiashvili, I. N.; Kosovichev, A. G.

    2012-09-10

    Results of a statistical analysis of solar granulation are presented. A data set of 36 images of a quiet-Sun area on the solar disk center was used. The data were obtained with the 1.6 m clear aperture New Solar Telescope at Big Bear Solar Observatory and with a broadband filter centered at the TiO (705.7 nm) spectral line. The very high spatial resolution of the data (diffraction limit of 77 km and pixel scale of 0.''0375) augmented by the very high image contrast (15.5% {+-} 0.6%) allowed us to detect for the first time a distinct subpopulation of mini-granular structures. These structures are dominant on spatial scales below 600 km. Their size is distributed as a power law with an index of -1.8 (which is close to the Kolmogorov's -5/3 law) and no predominant scale. The regular granules display a Gaussian (normal) size distribution with a mean diameter of 1050 km. Mini-granular structures contribute significantly to the total granular area. They are predominantly confined to the wide dark lanes between regular granules and often form chains and clusters, but different from magnetic bright points. A multi-fractality test reveals that the structures smaller than 600 km represent a multi-fractal, whereas on larger scales the granulation pattern shows no multi-fractality and can be considered as a Gaussian random field. The origin, properties, and role of the population of mini-granular structures in the solar magnetoconvection are yet to be explored.

  14. Receive Transmit Telescope Telescope

    E-Print Network [OSTI]

    technologies for the Bifocal Relay Mirror Spacecraft and verify these technologies with the experimental test for Bifocal Relay Mirror Spacecraft Jae Jun Kim* , Tim Sands , and Brij N. Agrawal Naval Postgraduate School Relay Mirror Spacecraft. In this paper, development of the Bifocal Relay Mirror Spacecraft experimental

  15. Large-scale gyrokinetic particle simulation of

    E-Print Network [OSTI]

    Oliker, Leonid

    areas of research including plasma astrophysics and fusion energy science. Fusion is the power source that are still needed to make fusion energy a practical realization. Research in plasma science requiresLarge-scale gyrokinetic particle simulation of microturbulence in magnetically confined fusion

  16. Site Monitoring Area Maps

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and roads The spatial location and boundaries for each Site shown on the Site Monitoring Area maps originate from activities conducted under the Compliance Order on Consent with...

  17. THE M31 VELOCITY VECTOR. I. HUBBLE SPACE TELESCOPE PROPER-MOTION MEASUREMENTS

    SciTech Connect (OSTI)

    Sohn, Sangmo Tony; Anderson, Jay; Van der Marel, Roeland P.

    2012-07-01

    We present the first proper-motion (PM) measurements for the galaxy M31. We obtained new V-band imaging data with the Hubble Space Telescope ACS/WFC and the WFC3/UVIS instruments of three fields: a spheroid field near the minor axis, an outer disk field along the major axis, and a field on the Giant Southern Stream. The data provide five to seven year time baselines with respect to pre-existing deep first-epoch observations of the same fields. We measure the positions of thousands of M31 stars and hundreds of compact background galaxies in each field. High accuracy and robustness is achieved by building and fitting a unique template for each individual object. The average PM for each field is obtained from the average motion of the M31 stars between the epochs with respect to the background galaxies. For the three fields, the observed PMs ({mu}{sub W}, {mu}{sub N}) are, in units of mas yr{sup -1}, (- 0.0458, -0.0376) {+-} (0.0165, 0.0154), (- 0.0533, -0.0104) {+-} (0.0246, 0.0244), and (- 0.0179, -0.0357) {+-} (0.0278, 0.0272), respectively. The ability to average over large numbers of objects and over the three fields yields a final displacement accuracy of a few thousandths of a pixel, corresponding to only 12 {mu}as yr{sup -1}. This is comparable to what has been achieved for other Local Group galaxies using Very Long Baseline Array observations of water masers. Potential systematic errors are controlled by an analysis strategy that corrects for detector charge transfer inefficiency, spatially and time-dependent geometric distortion, and point-spread function variations. The robustness of the PM measurements and uncertainties are supported by the fact that data from different instruments, taken at different times and with different telescope orientations, as well as measurements of different fields, all yield statistically consistent results. Papers II and III of this series explore the implications of the new measurements for our understanding of the history, future, and mass of the Local Group.

  18. Investigation of Umbral Dots with the New Vacuum Solar Telescope

    E-Print Network [OSTI]

    Kaifan, Ji; Song, Feng; Yunfei, Yang; Hui, Deng; Feng, Wang

    2015-01-01

    Umbral dots (UDs) are small isolated brightening observed in sunspot umbrae. They are convective phenomena existing inside umbrae. UDs are usually divided into central UDs (CUDs) and peripheral UDs (PUDs) with respect to their positions inside an umbra. Our purpose is to investigate UD properties and analyze their relationships, and further to find whether or not the properties depend on the umbral magnetic field variation. For the purpose, we selected the high-resolution TiO images of four active regions (ARs) obtained under the best seeing conditions with the \\emph{New Vacuum Solar Telescope} (NVST) in Fuxian Solar Observatory of Yunnan Astronomical Observatory, China. The four ARs (NOAA 11598, 11801, 12158, and 12178) include six sunspots. A total of 1220 CUDs were extracted from six sunspots, and 603 PUDs from three sunspots. Meanwhile, the radial component of the magnetic field of the sunspots obtained with the \\emph{Helioseismic and Magnetic Imager} onboard the \\emph{Solar Dynamics Observatory} was used...

  19. THE INFRARED TELESCOPE FACILITY (IRTF) SPECTRAL LIBRARY: COOL STARS

    SciTech Connect (OSTI)

    Rayner, John T.; Cushing, Michael C.; Vacca, William D. E-mail: michael.cushing@gmail.com

    2009-12-01

    We present a 0.8-5 {mu}m spectral library of 210 cool stars observed at a resolving power of R {identical_to} {lambda}/{delta}{lambda} {approx} 2000 with the medium-resolution infrared spectrograph, SpeX, at the 3.0 m NASA Infrared Telescope Facility (IRTF) on Mauna Kea, Hawaii. The stars have well-established MK spectral classifications and are mostly restricted to near-solar metallicities. The sample not only contains the F, G, K, and M spectral types with luminosity classes between I and V, but also includes some AGB, carbon, and S stars. In contrast to some other spectral libraries, the continuum shape of the spectra is measured and preserved in the data reduction process. The spectra are absolutely flux calibrated using the Two Micron All Sky Survey photometry. Potential uses of the library include studying the physics of cool stars, classifying and studying embedded young clusters and optically obscured regions of the Galaxy, evolutionary population synthesis to study unresolved stellar populations in optically obscured regions of galaxies and synthetic photometry. The library is available in digital form from the IRTF Web site.

  20. Testing and Performance of UFFO Burst Alert & Trigger Telescope

    E-Print Network [OSTI]

    Ripa, J; Lee, J; Park, I H; Kim, J E; Lim, H; Jeong, S; Castro-Tirado, A J; Connell, P H; Eyles, C; Reglero, V; Rodrigo, J M; Bogomolov, V; Panasyuk, M I; Petrov, V; Svertilov, S; Yashin, I; Brandt, S; Budtz-Jorgensen, C; Chang, Y -Y; Chen, P; Huang, M A; Liu, T -C; Nam, J W; Wang, M -Z; Chen, C R; Choi, H S; Kim, S -W; Min, K W

    2015-01-01

    The Ultra-Fast Flash Observatory pathfinder (UFFO-p) is a new space mission dedicated to detect Gamma-Ray Bursts (GRBs) and rapidly follow their afterglows in order to provide early optical/ultraviolet measurements. A GRB location is determined in a few seconds by the UFFO Burst Alert & Trigger telescope (UBAT) employing the coded mask imaging technique and the detector combination of Yttrium Oxyorthosilicate (YSO) scintillating crystals and multi-anode photomultiplier tubes. The results of the laboratory tests of UBAT's functionality and performance are described in this article. The detector setting, the pixel-to-pixel response to X-rays of different energies, the imaging capability for rays, the localization accuracy measurements, and the combined test with the Block for X-ray and Gamma-Radiation Detection (BDRG) scintillator detector to check the efficiency of UBAT are all described. The UBAT instrument has been assembled and integrated with other equipment on UFFO-p and should be launche...

  1. Hubble Space Telescope Observations of Novae in M49

    E-Print Network [OSTI]

    Laura Ferrarese; Patrick Cote; Andres Jordan

    2003-09-30

    A search for novae in M49 (NGC 4472) has been undertaken with the Hubble Space Telescope. A 55-day observing campaign in F555W (19 epochs) and F814W (five epochs) has led to the discovery of nine novae. We find that M49 may be under-abundant in slow, faint novae relative to the Milky Way and M31. Instead, the decline rates of the M49 novae are remarkably similar to those of novae in the LMC. This fact argues against a simple classification of novae in "bulge" and "disk" sub-classes. We examine the Maximum-Magnitude versus Rate of Decline (MMRD) relation for novae in M49, finding only marginal agreement with the Galactic and M31 MMRD relations. A recalibration of the Buscombe-de Vaucouleurs relation gives an absolute magnitude 15 days past maximum of M_{V,15} = -6.36+/-0.19, which is substantially brighter than previous calibrations based on Galactic novae. Monte Carlo simulations yield a global nova rate for M49 of 100{+35}{-30} per year, and a luminosity-specific nova rate in the range \

  2. Large Customers (DR Sellers)

    SciTech Connect (OSTI)

    Kiliccot, Sila

    2011-10-25

    State of the large customers for demand response integration of solar and wind into electric grid; openADR; CAISO; DR as a pseudo generation; commercial and industrial DR strategies; California regulations

  3. Pattern Alteration: Large Abdomen 

    E-Print Network [OSTI]

    2006-08-04

    A large abdomen causes the hemline on a skirt to hike in front and pulls the side seam forward. This publication gives instructions on altering patterns for a basic skirt and pants....

  4. Geothermal br Resource br Area Geothermal br Resource br Area...

    Open Energy Info (EERE)

    Area Central Nevada Seismic Zone Pull Apart in Strike Slip Fault Zone Ordovician shale quartzite MW K Blue Mountain Geothermal Area Blue Mountain Geothermal Area Northwest...

  5. Detectors for the James Webb Space Telescope Near-Infrared Spectrograph I: Readout Mode, Noise Model, and Calibration Considerations

    E-Print Network [OSTI]

    Bernard J. Rauscher; Ori Fox; Pierre Ferruit

    2007-06-15

    We describe how the James Webb Space Telescope (JWST) Near-Infrared Spectrograph's (NIRSpec's) detectors will be read out, and present a model of how noise scales with the number of multiple non-destructive reads sampling-up-the-ramp. We believe that this noise model, which is validated using real and simulated test data, is applicable to most astronomical near-infrared instruments. We describe some non-ideal behaviors that have been observed in engineering grade NIRSpec detectors, and demonstrate that they are unlikely to affect NIRSpec sensitivity, operations, or calibration. These include a HAWAII-2RG reset anomaly and random telegraph noise (RTN). Using real test data, we show that the reset anomaly is: (1) very nearly noiseless and (2) can be easily calibrated out. Likewise, we show that large-amplitude RTN affects only a small and fixed population of pixels. It can therefore be tracked using standard pixel operability maps.

  6. A Small Multi-Wire Telescope for High Energy Cosmic Ray Muon Detection

    E-Print Network [OSTI]

    Maghrabi, Abdullrahnan; Aldosari, A; Almuteri, M

    2016-01-01

    Different types of ground-based detectors have been developed and deployed around the world to monitor and study CR variations. We have designed, constructed and operated a three layer small (20x20 cm2) multiwire proportional chamber MWPC telescope for cosmic ray muon observations. In this paper, the technical aspects of this detector will be briefly discussed. The abilities of the telescope in detecting high nergy cosmic ray muons (primaries higher than 20 GeV) were established. The telescope performs well in this sense and showed comparable results with a 1 m2 scintillator detector.

  7. KM3NeT: A Next Generation Neutrino Telescope in the Mediterranean Sea

    E-Print Network [OSTI]

    A. Kappes; for the KM3NeT Consortium

    2007-11-05

    To complement the IceCube neutrino telescope currently under construction at the South Pole, the three Mediterranean neutrino telescope projects ANTARES, NEMO and NESTOR have joined forces to develop, construct and operate a km^3-scale neutrino telescope in the Mediterranean Sea. Since February 2006, the technical specifications and performance of such a detector are studied in the framework of a 3-year EU-funded Design Study. In 2009 a technical design report will be released laying the foundations for the construction of the detector. In the following, the current status of the Design Study is presented and examples of solutions for the technical challenges are discussed.

  8. West Central North East Area of Tucson

    E-Print Network [OSTI]

    Hall, Sharon J.

    a, b) in urbanized areas. The Tucson Hummingbird Project (THP) is a citizen-science, reconciliation for migrating ones. Citizen Science and OutreachCitizen Science and Outreach The latter was achieved with citizen scientists via large-scale outreach to the local community. Projects such as the THP can

  9. Neutron Science Research Areas | ORNL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Home | Science & Discovery | Neutron Science | Research Areas SHARE Research Areas Neutron scattering research at ORNL covers four broad research areas: biology and soft...

  10. Mapping compound cosmic telescopes containing multiple projected cluster-scale halos

    SciTech Connect (OSTI)

    Ammons, S. Mark; Wong, Kenneth C.; Zabludoff, Ann I.; Keeton, Charles R. E-mail: kwong@as.arizona.edu E-mail: keeton@physics.rutgers.edu

    2014-01-20

    Lines of sight with multiple projected cluster-scale gravitational lenses have high total masses and complex lens plane interactions that can boost the area of magnification, or étendue, making detection of faint background sources more likely than elsewhere. To identify these new 'compound' cosmic telescopes, we have found directions in the sky with the highest integrated mass densities, as traced by the projected concentrations of luminous red galaxies (LRGs). We use new galaxy spectroscopy to derive preliminary magnification maps for two such lines of sight with total mass exceeding ?3 × 10{sup 15} M {sub ?}. From 1151 MMT Hectospec spectra of galaxies down to i {sub AB} = 21.2, we identify two to three group- and cluster-scale halos in each beam. These are well traced by LRGs. The majority of the mass in beam J085007.6+360428 (0850) is contributed by Zwicky 1953, a massive cluster at z = 0.3774, whereas beam J130657.5+463219 (1306) is composed of three halos with virial masses of 6 × 10{sup 14}-2 × 10{sup 15} M {sub ?}, one of which is A1682. The magnification maps derived from our mass models based on spectroscopy and Sloan Digital Sky Survey photometry alone display substantial étendue: the 68% confidence bands on the lens plane area with magnification exceeding 10 for a source plane of z{sub s} = 10 are [1.2, 3.8] arcmin{sup 2} for 0850 and [2.3, 6.7] arcmin{sup 2} for 1306. In deep Subaru Suprime-Cam imaging of beam 0850, we serendipitously discover a candidate multiply imaged V-dropout source at z {sub phot} = 5.03. The location of the candidate multiply imaged arcs is consistent with the critical curves for a source plane of z = 5.03 predicted by our mass model. Incorporating the position of the candidate multiply imaged galaxy as a constraint on the critical curve location in 0850 narrows the 68% confidence band on the lens plane area with ? > 10 and z{sub s} = 10 to [1.8, 4.2] arcmin{sup 2}, an étendue range comparable to that of MACS 0717+3745 and El Gordo, two of the most powerful single cluster lenses known. The significant lensing power of our beams makes them powerful probes of reionization and galaxy formation in the early universe.

  11. Green Bank Telescope Studies of Giant Pulses from Millisecond Pulsars

    E-Print Network [OSTI]

    H. S. Knight; M. Bailes; R. N. Manchester; S. M. Ord; B. A. Jacoby

    2005-12-13

    We have conducted a search for giant pulses from four millisecond pulsars using the 100m Green Bank Telescope. Coherently dedispersed time-series from PSR J0218+4232 were found to contain giant pulses of very short intrinsic duration whose energies follow power-law statistics. The giant pulses are in phase with the two minima of the radio integrated pulse profile but are phase aligned with the peaks of the X-ray profile. Historically, individual pulses more than 10-20 times the mean pulse energy have been deemed to be ``giant pulses''. As only 4 of the 155 pulses had energies greater than 10 times the mean pulse-energy, we argue the emission mechanism responsible for giant pulses should instead be defined through: (a) intrinsic timescales of microsecond or nanosecond duration; (b) power-law energy statistics; and (c) emission occurring in narrow phase-windows coincident with the phase windows of non-thermal X-ray emission. Four short-duration pulses with giant-pulse characteristics were also observed from PSR B1957+20. As the inferred magnetic fields at the light cylinders of the millisecond pulsars that emit giant pulses are all very high, this parameter has previously been considered to be an indicator of giant pulse emissivity. However, the frequency of giant pulse emission from PSR~B1957+20 is significantly lower than for other millisecond pulsars that have similar magnetic fields at their light cylinders. This suggests that the inferred magnetic field at the light cylinder is a poor indicator of the rate of emission of giant pulses.

  12. Fermi Gamma-Ray Space Telescope: High-Energy Results From the...

    Office of Scientific and Technical Information (OSTI)

    Gamma-Ray Space Telescope: High-Energy Results From the First Year Michelson, P.F.; KIPAC, Menlo Park; Atwood, W.B.; Ritz, S.; UC, Santa Cruz UC, Santa Cruz, Phys. Dept....

  13. Photosensor Characterization for the Cherenkov Telescope Array: Silicon Photomultiplier versus Multi-Anode Photomultiplier Tube

    E-Print Network [OSTI]

    Bouvier, Aurelien; Johnson, Caitlin; Kuznetsov, Andrey; Williams, David; Otte, Nepomuk; Strausbaugh, Robert; Hidaka, Naoya; Tajima, Hiroyasu; Hinton, Jim; White, Richard; Errando, Manel; Mukherjee, Reshmi

    2013-01-01

    Photomultiplier tube technology has been the photodetector of choice for the technique of imaging atmospheric Cherenkov telescopes since its birth more than 50 years ago. Recently, new types of photosensors are being contemplated for the next generation Cherenkov Telescope Array. It is envisioned that the array will be partly composed of telescopes using a Schwarzschild-Couder two mirror design never built before which has significantly improved optics. The camera of this novel optical design has a small plate scale which enables the use of compact photosensors. We present an extensive and detailed study of the two most promising devices being considered for this telescope design: the silicon photomultiplier and the multi-anode photomultiplier tube. We evaluated their most critical performance characteristics for imaging gamma-ray showers, and we present our results in a cohesive manner to clearly evaluate the advantages and disadvantages that both types of device have to offer in the context of GeV-TeV gamma...

  14. A Continuous Homologation of Esters: An Efficient Telescoped Reduction–Olefination Sequence

    E-Print Network [OSTI]

    Webb, Damien

    A continuous protocol for the two-carbon homologation of esters to ?,?-unsaturated esters is described. This multireactor homologation telescopes an ester reduction, phosphonate deprotonation, and Horner–Wadsworth–Emmons ...

  15. Thin optic surface analysis for high resolution X-ray telescopes

    E-Print Network [OSTI]

    Akilian, Mireille

    2004-01-01

    The art of glass developed throughout the years has covered artifacts ranging from crude ornaments to high precision optics used in flat panel displays, hard disk drives, and x-ray telescopes. Methods for manufacturing ...

  16. ISIS polarimetry for ING support astronomers Isaac Newton Group of Telescopes

    E-Print Network [OSTI]

    ISIS polarimetry for ING support astronomers Isaac Newton Group of Telescopes Pablo Rodr 0.1 Document history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 ISIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.2 Setting up ISIS for spectropolarimetry . . . . . . . . . . . . . . . . . . . . . 4 1

  17. Hubble Space Telescope Cycle 5 General Observer Pro* Imaging of Two Dwarf Galaxies in Tidal Tails

    E-Print Network [OSTI]

    Hibbard, John

    Hubble Space Telescope Cycle 5 General Observer Pro* *posal Woodlawn Drive Honolulu, HI 96822 Telephone: 808:Galaxies & Clusters Instruments: WFPC2 Cycle 5 primary orbits:11 Cycle 5 parallel orbits:0 Abstract

  18. Geographic Area Month

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    Fuels by PAD District and State (Cents per Gallon Excluding Taxes) - Continued Geographic Area Month No. 1 Distillate No. 2 Distillate a No. 4 Fuel b Sales to End Users Sales for...

  19. Decontamination & decommissioning focus area

    SciTech Connect (OSTI)

    1996-08-01

    In January 1994, the US Department of Energy Office of Environmental Management (DOE EM) formally introduced its new approach to managing DOE`s environmental research and technology development activities. The goal of the new approach is to conduct research and development in critical areas of interest to DOE, utilizing the best talent in the Department and in the national science community. To facilitate this solutions-oriented approach, the Office of Science and Technology (EM-50, formerly the Office of Technology Development) formed five Focus AReas to stimulate the required basic research, development, and demonstration efforts to seek new, innovative cleanup methods. In February 1995, EM-50 selected the DOE Morgantown Energy Technology Center (METC) to lead implementation of one of these Focus Areas: the Decontamination and Decommissioning (D & D) Focus Area.

  20. The optical reflector system for the CANGAROO-II imaging atmospheric Cherenkov telescope

    E-Print Network [OSTI]

    A. Kawachi; Y. Hayami; J. Jimbo; S. Kamei; T. Kifune; H. Kubo; J. Kushida; S. LeBohec; K. Miyawaki; M. Mori; K. Nishijima; J. R. Patterson; R. Suzuki; T. Tanimori; S. Yanagita; T. Yoshikoshi; A. Yuki

    2000-07-14

    A new imaging atmospheric Cherenkov telescope (CANGAROO-II) with a light-weight reflector has been constructed. Light, robust, and durable mirror facets of containing CFRP (Carbon Fiber Reinforced Plastic) laminates were developed for the telescope. The attitude of each facet can be adjusted by stepping motors. In this paper, we describe the design, manufacturing, alignment procedure, and the performance of the CANGAROO-II optical reflector system.

  1. The optical reflector system for the CANGAROO-II imaging atmospheric Cherenkov telescope

    E-Print Network [OSTI]

    Kawachi, A; Jimbo, J; Kamei, S; Kifune, T; Kubo, H; Kushida, J; Le Bohec, S; Miyawaki, K; Mori, M; Nishijima, K; Patterson, J R; Suzuki, R; Tanimori, T; Yanagita, S; Yoshikoshi, T; Yuki, A

    2001-01-01

    A new imaging atmospheric Cherenkov telescope (CANGAROO-II) with a light-weight reflector has been constructed. Light, robust, and durable mirror facets of containing CFRP (Carbon Fiber Reinforced Plastic) laminates were developed for the telescope. The attitude of each facet can be adjusted by stepping motors. In this paper, we describe the design, manufacturing, alignment procedure, and the performance of the CANGAROO-II optical reflector system.

  2. The use of large plot rainfall simulation to investigate 

    E-Print Network [OSTI]

    Sorenson, Joshua Russell

    2006-04-12

    In this study, large scale rainfall simulation was used to evaluate runoff generation from canopy and intercanopy areas within an ashe juniper woodland of the Edwards Plateau. One 3 x 12 m site was established beneath the ...

  3. 300 Area Disturbance Report

    SciTech Connect (OSTI)

    LL Hale; MK Wright; NA Cadoret

    1999-01-07

    The objective of this study was to define areas of previous disturbance in the 300 Area of the U.S. Department of Energy (DOE) Hanford Site to eliminate these areas from the cultural resource review process, reduce cultural resource monitoring costs, and allow cultural resource specialists to focus on areas where subsurface disturbance is minimal or nonexistent. Research into available sources suggests that impacts from excavations have been significant wherever the following construction activities have occurred: building basements and pits, waste ponds, burial grounds, trenches, installation of subsurface pipelines, power poles, water hydrants, and well construction. Beyond the areas just mentioned, substrates in the' 300 Area consist of a complex, multidimen- sional mosaic composed of undisturbed stratigraphy, backfill, and disturbed sediments; Four Geographic Information System (GIS) maps were created to display known areas of disturbance in the 300 Area. These maps contain information gleaned from a variety of sources, but the primary sources include the Hanford GIS database system, engineer drawings, and historic maps. In addition to these maps, several assumptions can be made about areas of disturbance in the 300 Area as a result of this study: o o Buried pipelines are not always located where they are mapped. As a result, cultural resource monitors or specialists should not depend on maps depicting subsurface pipelines for accurate locations of previous disturbance. Temporary roads built in the early 1940s were placed on layers of sand and gravel 8 to 12 in. thick. Given this information, it is likely that substrates beneath these early roads are only minimally disturbed. Building foundations ranged from concrete slabs no more than 6 to 8 in. thick to deeply excavated pits and basements. Buildings constructed with slab foundations are more numerous than may be expected, and minimally disturbed substrates may be expected in these locations. Historic black and white photographs provide a partial record of some excavations, including trenches, building basements, and material lay-down yards. Estimates of excavation depth and width can be made, but these estimates are not accurate enough to pinpoint the exact location where the disturbedhmdisturbed interface is located (e.g., camera angles were such that depths and/or widths of excavations could not be accurately determined or estimated). In spite of these limitations, these photographs provide essential information. Aerial and historic low-level photographs have captured what appears to be backfill throughout much of the eastern portion of the 300 Area-near the Columbia River shoreline. This layer of fill has likely afforded some protection for the natural landscape buried beneath the fill. This assumption fits nicely with the intermittent and inadvertent discoveries of hearths and stone tools documented through the years in this part of the 300 Area. Conversely, leveling of sand dunes appears to be substantial in the northwestern portion of the 300 Area during the early stages of development. o Project files and engineer drawings do not contain information on any impromptu but necessary adjustments made on the ground during project implementation-after the design phase. Further, many projects are planned and mapped but never implemented-this information is also not often placed in project files. Specific recommendations for a 300 Area cultural resource monitoring strategy are contained in the final section of this document. In general, it is recommended that monitoring continue for all projects located within 400 m of the Columbia River. The 400-m zone is culturally sensitive and likely retains some of the most intact buried substrates in the 300 Area.

  4. Liverpool Telescope 2: a new robotic facility for rapid transient follow-up

    E-Print Network [OSTI]

    Copperwheat, C M; Barnsley, R M; Bates, S D; Bersier, D; Bode, M F; Carter, D; Clay, N R; Collins, C A; Darnley, M J; Davis, C J; Gutierrez, C M; Harman, D J; James, P A; Knapen, J; Kobayashi, S; Marchant, J M; Mazzali, P A; Mottram, C J; Mundell, C G; Newsam, A; Oscoz, A; Palle, E; Piascik, A; Rebolo, R; Smith, R J

    2014-01-01

    The Liverpool Telescope is one of the world's premier facilities for time domain astronomy. The time domain landscape is set to radically change in the coming decade, with synoptic all-sky surveys such as LSST providing huge numbers of transient detections on a nightly basis; transient detections across the electromagnetic spectrum from other major facilities such as SVOM, SKA and CTA; and the era of `multi-messenger astronomy', wherein astrophysical events are detected via non-electromagnetic means, such as neutrino or gravitational wave emission. We describe here our plans for the Liverpool Telescope 2: a new robotic telescope designed to capitalise on this new era of time domain astronomy. LT2 will be a 4-metre class facility co-located with the Liverpool Telescope at the Observatorio del Roque de Los Muchachos on the Canary island of La Palma. The telescope will be designed for extremely rapid response: the aim is that the telescope will take data within 30 seconds of the receipt of a trigger from another...

  5. HUBBLE SPACE TELESCOPE FAR ULTRAVIOLET SPECTROSCOPY OF THE RECURRENT NOVA T PYXIDIS

    SciTech Connect (OSTI)

    Godon, Patrick; Sion, Edward M. [Astronomy and Astrophysics, Villanova University, Villanova, PA 19085 (United States); Starrfield, Sumner [School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287 (United States); Livio, Mario; Williams, Robert E. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Woodward, Charles E. [Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, MN 55455 (United States); Kuin, Paul [Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey RH5 6NT (United Kingdom); Page, Kim L., E-mail: patrick.godon@villanova.edu, E-mail: edward.sion@villanova.edu, E-mail: sumner.starrfield@asu.edu, E-mail: mlivio@stsci.edu, E-mail: wms@stsci.edu, E-mail: chelsea@astro.umn.edu, E-mail: n.kuin@ucl.ac.uk, E-mail: klp5@leicester.ac.uk [Department of Physics and Astronomy, University of Leicester, Leicester, LE1 7RH (United Kingdom)

    2014-04-01

    With six recorded nova outbursts, the prototypical recurrent nova T Pyxidis (T Pyx) is the ideal cataclysmic variable system to assess the net change of the white dwarf mass within a nova cycle. Recent estimates of the mass ejected in the 2011 outburst ranged from a few ?10{sup –5} M {sub ?} to 3.3 × 10{sup –4} M {sub ?}, and assuming a mass accretion rate of 10{sup –8}-10{sup –7} M {sub ?} yr{sup –1} for 44 yr, it has been concluded that the white dwarf in T Pyx is actually losing mass. Using NLTE disk modeling spectra to fit our recently obtained Hubble Space Telescope COS and STIS spectra, we find a mass accretion rate of up to two orders of magnitude larger than previously estimated. Our larger mass accretion rate is due mainly to the newly derived distance of T Pyx (4.8 kpc, larger than the previous 3.5 kpc estimate), our derived reddening of E(B – V) = 0.35 (based on combined IUE and GALEX spectra), and NLTE disk modeling (compared to blackbody and raw flux estimates in earlier works). We find that for most values of the reddening (0.25 ? E(B – V) ? 0.50) and white dwarf mass (0.70 M {sub ?} ? M {sub wd} ? 1.35 M {sub ?}) the accreted mass is larger than the ejected mass. Only for a low reddening (?0.25 and smaller) combined with a large white dwarf mass (0.9 M {sub ?} and larger) is the ejected mass larger than the accreted one. However, the best results are obtained for a larger value of reddening.

  6. STAGES: the Space Telescope A901/2 Galaxy Evolution Survey

    E-Print Network [OSTI]

    M. E. Gray; Christian Wolf; Marco Barden; Chien Y. Peng; Boris Haeussler; Eric F. Bell; Daniel H. McIntosh; Yicheng Guo; John A. R. Caldwell; David Bacon; Michael Balogh; Fabio D. Barazza; Asmus Boehm; Catherine Heymans; Knud Jahnke; Shardha Jogee; Eelco van Kampen; Kyle Lane; Klaus Meisenheimer; Sebastian F. Sánchez; Andy Taylor; Lutz Wisotzki; Xianzhong Zheng; David A. Green; R. J. Beswick; D. J. Saikia; Rachel Gilmour; Benjamin D. Johnson; Casey Papovich

    2008-11-24

    We present an overview of the Space Telescope A901/2 Galaxy Evolution Survey (STAGES). STAGES is a multiwavelength project designed to probe physical drivers of galaxy evolution across a wide range of environments and luminosity. A complex multi-cluster system at z~0.165 has been the subject of an 80-orbit F606W HST/ACS mosaic covering the full 0.5x0.5 (~5x5 Mpc^2) span of the supercluster. Extensive multiwavelength observations with XMM-Newton, GALEX, Spitzer, 2dF, GMRT, and the 17-band COMBO-17 photometric redshift survey complement the HST imaging. Our survey goals include simultaneously linking galaxy morphology with other observables such as age, star-formation rate, nuclear activity, and stellar mass. In addition, with the multiwavelength dataset and new high resolution mass maps from gravitational lensing, we are able to disentangle the large-scale structure of the system. By examining all aspects of environment we will be able to evaluate the relative importance of the dark matter halos, the local galaxy density, and the hot X-ray gas in driving galaxy transformation. This paper describes the HST imaging, data reduction, and creation of a master catalogue. We perform Sersic fitting on the HST images and conduct associated simulations to quantify completeness. In addition, we present the COMBO-17 photometric redshift catalogue and estimates of stellar masses and star-formation rates for this field. We define galaxy and cluster sample selection criteria which will be the basis for forthcoming science analyses, and present a compilation of notable objects in the field. Finally, we describe the further multiwavelength observations and announce public access to the data and catalogues.

  7. Clusters and Large-Scale Structure: the Synchrotron Keys

    E-Print Network [OSTI]

    Rudnick, L; Andernach, H; Battaglia, N; Brown, S; Brunetti, Gf; Burns, J; Clarke, T; Dolag, K; Farnsworth, D; Giovannini, G; Hallman, E; Johnston-Hollit, M; Jones, T W; Kang, H; Kassim, N; Kravtsov, A; Lazio, J; Lonsdale, C; McNamara, B; Myers, S; Owen, F; Pfrommer, C; Ryu, D; Sarazin, C; Subrahmanyan, R; Taylor, G; Taylor, R

    2009-01-01

    For over four decades, synchrotron-radiating sources have played a series of pathfinding roles in the study of galaxy clusters and large scale structure. Such sources are uniquely sensitive to the turbulence and shock structures of large-scale environments, and their cosmic rays and magnetic fields often play important dynamic and thermodynamic roles. They provide essential complements to studies at other wavebands. Over the next decade, they will fill essential gaps in both cluster astrophysics and the cosmological growth of structure in the universe, especially where the signatures of shocks and turbulence, or even the underlying thermal plasma itself, are otherwise undetectable. Simultaneously, synchrotron studies offer a unique tool for exploring the fundamental question of the origins of cosmic magnetic fields. This work will be based on the new generation of m/cm-wave radio telescopes now in construction, as well as major advances in the sophistication of 3-D MHD simulations.

  8. OLED area illumination source

    DOE Patents [OSTI]

    Foust, Donald Franklin (Scotia, NY); Duggal, Anil Raj (Niskayuna, NY); Shiang, Joseph John (Niskayuna, NY); Nealon, William Francis (Gloversville, NY); Bortscheller, Jacob Charles (Clifton Park, NY)

    2008-03-25

    The present invention relates to an area illumination light source comprising a plurality of individual OLED panels. The individual OLED panels are configured in a physically modular fashion. Each OLED panel comprising a plurality of OLED devices. Each OLED panel comprises a first electrode and a second electrode such that the power being supplied to each individual OLED panel may be varied independently. A power supply unit capable of delivering varying levels of voltage simultaneously to the first and second electrodes of each of the individual OLED panels is also provided. The area illumination light source also comprises a mount within which the OLED panels are arrayed.

  9. Lessons from Large-Scale Renewable Energy Integration Studies: Preprint

    SciTech Connect (OSTI)

    Bird, L.; Milligan, M.

    2012-06-01

    In general, large-scale integration studies in Europe and the United States find that high penetrations of renewable generation are technically feasible with operational changes and increased access to transmission. This paper describes other key findings such as the need for fast markets, large balancing areas, system flexibility, and the use of advanced forecasting.

  10. LIGHT CURVES OF 32 LARGE TRANSNEPTUNIAN OBJECTS

    SciTech Connect (OSTI)

    Benecchi, Susan D.; Sheppard, Scott S.

    2013-05-15

    We present observations of 32 primarily bright, newly discovered Transneptunian objects (TNOs) observable from the Southern Hemisphere during 39 nights of observation with the Irenee du Pont 2.5 m telescope at Las Campanas Observatory. Our dataset includes objects in all dynamical classes, but is weighted toward scattered objects. We find 15 objects for which we can fit periods and amplitudes to the data, and place light curve amplitude upper limits on the other 17 objects. Combining our sample with the larger light curve sample in the literature, we find a 3{sigma} correlation between light curve amplitude and absolute magnitude with fainter objects having larger light curve amplitudes. We looked for correlations between light curve and individual orbital properties, but did not find any statistically significant results. However, if we consider light curve properties with respect to object dynamical classification, we find statistically different distributions between the classical-scattered and classical-resonant populations at the 95.60% and 94.64% level, respectively, with the classical objects having larger amplitude light curves. The significance is 97.05% if the scattered and resonant populations are combined. The properties of binary light curves are largely consistent with the greater TNO population except in the case of tidally locked systems. All the Haumea family objects measured so far have light curve amplitudes and rotation periods {<=}10 hr, suggesting that they are not significantly different from the larger TNO population. We expect multiple factors are influencing object rotations: object size dominates light curve properties except in the case of tidal, or proportionally large collisional interactions with other TNOs, the influence of the latter being different for each TNO sub-population. We also present phase curves and colors for some of our objects.

  11. Plutonium focus area

    SciTech Connect (OSTI)

    NONE

    1996-08-01

    To ensure research and development programs focus on the most pressing environmental restoration and waste management problems at the U.S. Department of Energy (DOE), the Assistant Secretary for the Office of Environmental Management (EM) established a working group in August 1993 to implement a new approach to research and technology development. As part of this new approach, EM developed a management structure and principles that led to the creation of specific Focus Areas. These organizations were designed to focus the scientific and technical talent throughout DOE and the national scientific community on the major environmental restoration and waste management problems facing DOE. The Focus Area approach provides the framework for intersite cooperation and leveraging of resources on common problems. After the original establishment of five major Focus Areas within the Office of Technology Development (EM-50, now called the Office of Science and Technology), the Nuclear Materials Stabilization Task Group (EM-66) followed the structure already in place in EM-50 and chartered the Plutonium Focus Area (PFA). The following information outlines the scope and mission of the EM, EM-60, and EM-66 organizations as related to the PFA organizational structure.

  12. Subsurface contaminants focus area

    SciTech Connect (OSTI)

    1996-08-01

    The US Department of Enregy (DOE) Subsurface Contaminants Focus Area is developing technologies to address environmental problems associated with hazardous and radioactive contaminants in soil and groundwater that exist throughout the DOE complex, including radionuclides, heavy metals; and dense non-aqueous phase liquids (DNAPLs). More than 5,700 known DOE groundwater plumes have contaminated over 600 billion gallons of water and 200 million cubic meters of soil. Migration of these plumes threatens local and regional water sources, and in some cases has already adversely impacted off-site rsources. In addition, the Subsurface Contaminants Focus Area is responsible for supplying technologies for the remediation of numerous landfills at DOE facilities. These landfills are estimated to contain over 3 million cubic meters of radioactive and hazardous buried Technology developed within this specialty area will provide efective methods to contain contaminant plumes and new or alternative technologies for development of in situ technologies to minimize waste disposal costs and potential worker exposure by treating plumes in place. While addressing contaminant plumes emanating from DOE landfills, the Subsurface Contaminants Focus Area is also working to develop new or alternative technologies for the in situ stabilization, and nonintrusive characterization of these disposal sites.

  13. Large-Scale Information Systems

    SciTech Connect (OSTI)

    D. M. Nicol; H. R. Ammerlahn; M. E. Goldsby; M. M. Johnson; D. E. Rhodes; A. S. Yoshimura

    2000-12-01

    Large enterprises are ever more dependent on their Large-Scale Information Systems (LSLS), computer systems that are distinguished architecturally by distributed components--data sources, networks, computing engines, simulations, human-in-the-loop control and remote access stations. These systems provide such capabilities as workflow, data fusion and distributed database access. The Nuclear Weapons Complex (NWC) contains many examples of LSIS components, a fact that motivates this research. However, most LSIS in use grew up from collections of separate subsystems that were not designed to be components of an integrated system. For this reason, they are often difficult to analyze and control. The problem is made more difficult by the size of a typical system, its diversity of information sources, and the institutional complexities associated with its geographic distribution across the enterprise. Moreover, there is no integrated approach for analyzing or managing such systems. Indeed, integrated development of LSIS is an active area of academic research. This work developed such an approach by simulating the various components of the LSIS and allowing the simulated components to interact with real LSIS subsystems. This research demonstrated two benefits. First, applying it to a particular LSIS provided a thorough understanding of the interfaces between the system's components. Second, it demonstrated how more rapid and detailed answers could be obtained to questions significant to the enterprise by interacting with the relevant LSIS subsystems through simulated components designed with those questions in mind. In a final, added phase of the project, investigations were made on extending this research to wireless communication networks in support of telemetry applications.

  14. Composting Large Animal Carcasses 

    E-Print Network [OSTI]

    Auvermann, Brent W.; Mukhtar, Saqib; Heflin, Kevin

    2006-10-31

    and Kevin Heflin* Livestock producers and large-animal veterinar- ians face a growing problem in rural Texas?what to do with dead animals. Rendering services are getting more expensive and harder to come by, and just leav- ing carcasses to predators... set up a polyethylene tank to hold water and rig it with a float valve so that it stays ?topped off? and ready. If one of your stock tanks stays wet year-round, you can simply lay a suction line with a foot valve into the middle of the pond...

  15. Sustainability of Very Large Photovoltaic DeploymentSustainability of Very Large Photovoltaic Deployment email: vmf5@columbia.edu

    E-Print Network [OSTI]

    Ohta, Shigemi

    Criteria Low Cost Resource Availability Lowest Environmental Impact Affordability in a competitive world Te: Research Areas #12;7 Life Cycle Environmental ImpactsLife Cycle Environmental Impacts Raw Material1 Sustainability of Very Large Photovoltaic DeploymentSustainability of Very Large Photovoltaic

  16. Large Magnetization at Carbon Surfaces

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Large Magnetization at Carbon Surfaces Large Magnetization at Carbon Surfaces Print Wednesday, 31 August 2011 00:00 From organic matter to pencil lead, carbon is a versatile...

  17. In-orbit focal adjustment of the AKARI telescope with IRC images

    E-Print Network [OSTI]

    H. Kaneda; W. Kim; T. Onaka; T. Wada; Y. Ita; I. Sakon; T. Takagi

    2007-06-01

    AKARI currently in space carries onboard a cryogenically-cooled lightweight telescope with silicon carbide mirrors. The wavefront error of the AKARI telescope obtained in laboratory measurements at 9 K showed that expected in-orbit imaging performance was diffraction-limited at a wavelength of 6.2 um. The AKARI telescope has a function of focus adjustment by shifting the secondary mirror in parallel to the optical axis. On the 4th day after the jettison of the cryostat aperture lid in the orbit, we observed a star with the InfraRed Camera (IRC) onboard AKARI. Since the initial star images observed in the near-infrared (IR) bands were significantly blurred, we twice moved the secondary mirror for the focal adjustment based on the results of model analyses as well as data analyses of the near-IR images. In consequence, we have successfully adjusted the focus of the telescope. The in-orbit imaging performance thus obtained for the AKARI telescope is diffraction-limited at a wavelength of 7.3 um, slightly degraded from that expected from the laboratory measurement.

  18. SPATIOTEMPORAL MODELS IN THE ESTIMATION OF AREA PRECIPITATION

    E-Print Network [OSTI]

    Lisbon, University of

    SPATIOTEMPORAL MODELS IN THE ESTIMATION OF AREA PRECIPITATION Eduardo Severino and Teresa Alpuim University of Lisbon, Portugal SUMMARY Since area precipitation measurements are difficult to obtain because of the large spatial and time variability of the precipitation field, the development of statistical methods

  19. Program Areas | National Security | ORNL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Organizations National Security Home | Science & Discovery | National Security | Program Areas SHARE Program Areas image Oak Ridge National Laboratory (ORNL) has a robust...

  20. THE DEEP BLUE COLOR OF HD 189733b: ALBEDO MEASUREMENTS WITH HUBBLE SPACE TELESCOPE/SPACE TELESCOPE IMAGING SPECTROGRAPH AT VISIBLE WAVELENGTHS

    SciTech Connect (OSTI)

    Evans, Thomas M.; Aigrain, Suzanne; Barstow, Joanna K.; Pont, Frederic; Sing, David K.; Desert, Jean-Michel; Knutson, Heather A.; Gibson, Neale; Heng, Kevin; Lecavelier des Etangs, Alain

    2013-08-01

    We present a secondary eclipse observation for the hot Jupiter HD 189733b across the wavelength range 290-570 nm made using the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. We measure geometric albedos of A{sub g} = 0.40 {+-} 0.12 across 290-450 nm and A{sub g} < 0.12 across 450-570 nm at 1{sigma} confidence. The albedo decrease toward longer wavelengths is also apparent when using six wavelength bins over the same wavelength range. This can be interpreted as evidence for optically thick reflective clouds on the dayside hemisphere with sodium absorption suppressing the scattered light signal beyond {approx}450 nm. Our best-fit albedo values imply that HD 189733b would appear a deep blue color at visible wavelengths.