WorldWideScience

Sample records for celestial south pole

  1. ASTEP South: An Antarctic Search for Transiting Planets around the celestial South pole

    CERN Document Server

    Crouzet, Nicolas; Blazit, Alain; Bonhomme, Serge; Fanteï-Caujolle, Yan; Fressin, François; Guillot, Tristan; Schmider, François-Xavier; Valbousquet, Franck; Bondoux, Erick; Challita, Zalpha; Abe, Lyu; Daban, Jean-Baptiste; Gouvret, Carole

    2008-01-01

    ASTEP South is the first phase of the ASTEP project that aims to determine the quality of Dome C as a site for future photometric searches for transiting exoplanets and discover extrasolar planets from the Concordia base in Antarctica. ASTEP South consists of a front-illuminated 4k x 4k CCD camera, a 10 cm refractor, and a simple mount in a thermalized enclosure. A double-glass window is used to reduce temperature variations and its accompanying turbulence on the optical path. The telescope is fixed and observes a 4 x 4 square degrees field of view centered on the celestial South pole. With this design, A STEP South is very stable and observes with low and constant airmass, both being important issues for photometric precision. We present the project, we show that enough stars are present in our field of view to allow the detection of one to a few transiting giant planets, and that the photometric precision of the instrument should be a few mmag for stars brighter than magnitude 12 and better than 10 mmag for...

  2. Brightness and color of the integrated starlight at celestial, ecliptic and galactic poles

    CERN Document Server

    Nawar, S; Mikhail, J S; Morcos, A B

    2010-01-01

    From photoelectric observations of night sky brightness carried out at Abu-Simbel, Asaad et al. (1979) have obtained values of integrated starlight brightness at different Galactic latitudes. These data have been used in the present work to obtain the brightness and color of the integrated starlight at North and South Celestial, Ecliptic and Galactic Poles. The present values of the brightness are expressed in S10 units and mag/arcsec2. Our results have been compared with that obtained by other investigators using photometric and star counts techniques. The B-V and B-R have been calculated and the results are compared with that obtained by other investigators.

  3. South Pole Telescope optics.

    Science.gov (United States)

    Padin, S; Staniszewski, Z; Keisler, R; Joy, M; Stark, A A; Ade, P A R; Aird, K A; Benson, B A; Bleem, L E; Carlstrom, J E; Chang, C L; Crawford, T M; Crites, A T; Dobbs, M A; Halverson, N W; Heimsath, S; Hills, R E; Holzapfel, W L; Lawrie, C; Lee, A T; Leitch, E M; Leong, J; Lu, W; Lueker, M; McMahon, J J; Meyer, S S; Mohr, J J; Montroy, T E; Plagge, T; Pryke, C; Ruhl, J E; Schaffer, K K; Shirokoff, E; Spieler, H G; Vieira, J D

    2008-08-20

    The South Pole Telescope is a 10 m diameter, wide-field, offset Gregorian telescope with a 966-pixel, millimeter-wave, bolometer array receiver. The telescope has an unusual optical system with a cold stop around the secondary. The design emphasizes low scattering and low background loading. All the optical components except the primary are cold, and the entire beam from prime focus to the detectors is surrounded by cold absorber.

  4. South Pole Telescope optics.

    Science.gov (United States)

    Padin, S; Staniszewski, Z; Keisler, R; Joy, M; Stark, A A; Ade, P A R; Aird, K A; Benson, B A; Bleem, L E; Carlstrom, J E; Chang, C L; Crawford, T M; Crites, A T; Dobbs, M A; Halverson, N W; Heimsath, S; Hills, R E; Holzapfel, W L; Lawrie, C; Lee, A T; Leitch, E M; Leong, J; Lu, W; Lueker, M; McMahon, J J; Meyer, S S; Mohr, J J; Montroy, T E; Plagge, T; Pryke, C; Ruhl, J E; Schaffer, K K; Shirokoff, E; Spieler, H G; Vieira, J D

    2008-08-20

    The South Pole Telescope is a 10 m diameter, wide-field, offset Gregorian telescope with a 966-pixel, millimeter-wave, bolometer array receiver. The telescope has an unusual optical system with a cold stop around the secondary. The design emphasizes low scattering and low background loading. All the optical components except the primary are cold, and the entire beam from prime focus to the detectors is surrounded by cold absorber. PMID:18716649

  5. The South Pole Telescope

    CERN Document Server

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

    2004-01-01

    A new 10 meter diameter telescope is being constructed for deployment at the NSF South Pole research station. The telescope is designed for conducting large-area millimeter and sub-millimeter wave surveys of faint, low contrast emission, as required to map primary and secondary anisotropies in the cosmic microwave background. To achieve the required sensitivity and resolution, the telescope design employs an off-axis primary with a 10m diameter clear aperture. The full aperture and the associated optics will have a combined surface accuracy of better than 20 microns rms to allow precision operation in the submillimeter atmospheric windows. The telescope will be surrounded with a large reflecting ground screen to reduce sensitivity to thermal emission from the ground and local interference. The optics of the telescope will support a square degree field of view at 2mm wavelength and will feed a new 1000-element micro-lithographed planar bolometric array with superconducting transition-edge sensors and frequency...

  6. The South Pole Telescope

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-11-04

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

  7. Lunar South Pole Mission (LSPM) :

    OpenAIRE

    Hobbs, Stephen

    2003-01-01

    This report is a summary of the group design project of the MSc in Astronautics and Space Engineering at Cranfield University for the year 1996/97. The project was a feasibility study of a European unmanned mission to the lunar south pole to carry out scientific study. The mission proposed uses two spacecraft: (1) an orbiter to take images of the proposed landing site, to measure the Moon’s gravitational field, and to act as a communications relay, and (2) a larger lander wh...

  8. Spectrum of the Anomalous Microwave Emission in the North Celestial Pole with WMAP 7-Year data

    CERN Document Server

    Bonaldi, Anna; 10.1155/2012/853927

    2013-01-01

    We estimate the frequency spectrum of the diffuse anomalous microwave emission (AME) on the North Celestial Pole (NCP) region of the sky with the Correlated Component Analysis (CCA) component separation method applied to WMAP 7-yr data. The NCP is a suitable region for this analysis because the AME is weakly contaminated by synchrotron and free-free emission. By modeling the AME component as a peaked spectrum we estimate the peak frequency to be $21.7\\pm0.8$\\,GHz, in agreement with previous analyses which favored $\

  9. Initial deep LOFAR observations of Epoch of Reionization windows: I. The North Celestial Pole

    CERN Document Server

    Yatawatta, S; Brentjens, M A; Labropoulos, P; Pandey, V N; Kazemi, S; Zaroubi, S; Koopmans, L V E; Offringa, A R; Jelic, V; Rubi, O Martinez; Veligatla, V; Wijnholds, S J; Brouw, W N; Bernardi, G; Ciardi, B; Daiboo, S; Harker, G; Mellema, G; Schaye, J; Thomas, R; Vedantham, H; Chapman, E; Abdalla, F B; Alexov, A; Anderson, J; Avruch, I M; Batejat, F; Bell, M E; Bell, M R; Bentum, M; Best, P; Bonafede, A; Bregman, J; Breitling, F; van de Brink, R H; Broderick, J W; Bruggen, M; Conway, J; de Gasperin, F; de Geus, E; Duscha, S; Falcke, H; Fallows, R A; Ferrari, C; Frieswijk, W; Garrett, M A; Griessmeier, J M; Gunst, A W; Hassall, T E; Hessels, J W T; Hoeft, M; Iacobelli, M; Juette, E; Karastergiou, A; Kondratiev, V I; Kramer, M; Kuniyoshi, M; Kuper, G; van Leeuwen, J; Maat, P; Mann, G; McKean, J P; Mevius, M; Mol, J D; Munk, H; Nijboer, R; Noordam, J E; Norden, M J; Orru, E; Paas, H; Pandey-Pommier, M; Pizzo, R; Polatidis, A G; Reich, W; Rottgering, H J A; Sluman, J; Smirnov, O; Stappers, B; Tagger, M; Tang, Y; Tasse, C; ter Veen, S; Vermeulen, R; van Weeren, R J; Wise, M; Wucknitz, O; Zarka, P

    2013-01-01

    The aim of the LOFAR Epoch of Reionization (EoR) project is to detect the spectral fluctuations of the redshifted HI 21cm signal. This signal is weaker by several orders of magnitude than the astrophysical foreground signals and hence, in order to achieve this, very long integrations, accurate calibration for stations and ionosphere and reliable foreground removal are essential. One of the prospective observing windows for the LOFAR EoR project will be centered at the North Celestial Pole (NCP). We present results from observations of the NCP window using the LOFAR highband antenna (HBA) array in the frequency range 115 MHz to 163 MHz. The data were obtained in April 2011 during the commissioning phase of LOFAR. We used baselines up to about 30 km. With about 3 nights, of 6 hours each, effective integration we have achieved a noise level of about 100 microJy/PSF in the NCP window. Close to the NCP, the noise level increases to about 180 microJy/PSF, mainly due to additional contamination from unsubtracted nea...

  10. The 10 Meter South Pole Telescope

    CERN Document Server

    Carlstrom, J E; Aird, K A; Benson, B A; Bleem, L E; Busetti, S; Chang, C L; Chauvin, E; Cho, H -M; Crawford, T M; Crites, A T; Dobbs, M A; Halverson, N W; Heimsath, S; Holzapfel, W L; Hrubes, J D; Joy, M; Keisler, R; Lanting, T M; Lee, A T; Leitch, E M; Leong, J; Lu, W; Lueker, M; McMahon, J J; Mehl, J; Meyer, S S; Mohr, J J; Montroy, T E; Padin, S; Plagge, T; Pryke, C; Ruhl, J E; Schaffer, K K; Schwan, D; Shirokoff, E; Spieler, H G; Staniszewski, Z; Stark, A A; Vieira, K Vanderlinde J D

    2009-01-01

    The South Pole Telescope (SPT) is a 10 m diameter, wide-field, offset Gregorian telescope with a 966-pixel, multi-color, millimeter-wave, bolometer camera. It is located at the Amundsen-Scott South Pole station in Antarctica. The design of the SPT emphasizes careful control of spillover and scattering, to minimize noise and false signals due to ground pickup. The key initial project is a large-area survey at wavelengths of 3, 2 and 1.3 mm, to detect clusters of galaxies via the Sunyaev-Zeldovich (SZ) effect and to measure the high-l angular power spectrum of the cosmic microwave background (CMB). The data will be used to characterize the primordial matter power spectrum and to place constraints on the equation of state of dark energy.

  11. Neutrino Astronomy at the South Pole

    CERN Document Server

    Toale, P A

    2006-01-01

    IceCube is currently being built deep in the glacial ice beneath the South Pole. In its second year of construction, it is already larger than its predecessor, AMANDA. AMANDA continues to collect high energy neutrino and muon data as an independent detector until it is integrated with IceCube. After introducing both detectors, recent results from AMANDA and a status report on IceCube are presented.

  12. Neutrino Astronomy at the South Pole

    OpenAIRE

    Toale, P. A.; IceCube Collaboration

    2006-01-01

    Comment: Proceedings of the 2006 Rencontres de Moriond, Electroweak InteractionsIceCube is currently being built deep in the glacial ice beneath the South Pole. In its second year of construction, it is already larger than its predecessor, AMANDA. AMANDA continues to collect high energy neutrino and muon data as an independent detector until it is integrated with IceCube. After introducing both detectors, recent results from AMANDA and a status report on IceCube are presented

  13. CMB Observations with the South Pole Telescope

    Science.gov (United States)

    Keisler, Ryan

    2013-04-01

    I will describe a program of cosmological research centered on using measurements of the cosmic microwave background (CMB) to address questions relevant to physics: What is the absolute mass scale of neutrinos? How many species of neutrino-like particles were present in the early Universe? How does gravity behave on cosmological scales? Did inflation occur, and, if so, at what energy scale? A new generation of CMB experiments is targeting these questions, and I will focus on recent results from the South Pole Telescope (SPT). The SPT is a ground-based mm-wave observatory located at the geographic south pole in Antarctica, and in 2011 finished its initial, 2500 square-degree ``SPT-SZ'' survey. The data from this survey provided an unprecedented combination of resolution, area, and sensitivity, and has been used to make ground-breaking measurements of the CMB anisotropy and the gravitational lensing of the CMB. These measurements have, in conjunction with data from the WMAP satellite, led to strong constraints on the number of neutrino-like particle species present in the early universe and the shape of the power spectrum of primordial density fluctuations. The SPT-SZ data overlaps with the ongoing Dark Energy Survey (DES) footprint, and the joint dataset will provide new probes of large-scale structure, such as the relative velocities of massive galaxy clusters. In 2012, a new polarization-sensitive camera, SPTpol, was installed on the SPT, and I will summarize its performance and prospects for detecting the B-mode CMB polarization pattern. Finally, I will touch on what will be possible with a third-generation camera, SPT-3G. The leap in sensitivity provided by this camera will yield, for example, a constraint on the sum of the neutrino masses relevant for exploring the neutrino mass hierarchy.

  14. Measurement of acoustic attenuation in South Pole ice

    NARCIS (Netherlands)

    Abbasi, R.; Abdou, Y.; Abu-Zayyad, T.; Adams, J.; Aguilar, J.A.; Ahlers, M.; Andeen, K.; Auffenberg, J.; Bai, X.; Baker, M.; Barwick, S.W.; Bay, R.; Alba, J.L.B.; Beattie, K.; Beatty, J.J.; Bechet, S.; Becker, J.K.; Becker, K.H.; Benabderrahmane, M.L.; Berdermann, J.; Berghaus, P.; Berley, D.; Bernardini, E.; Bertrand, D.; Besson, D.Z.; Bissok, M.; Blaufuss, E.; Boersma, D.J.; Bohm, C.; Boser, S.; Botner, O.; Bradley, L.; Braun, J.; Buitink, S.; Carson, M.; Chirkin, D.; Christy, B.; Clem, J.; Clevermann, F.; Cohen, S.; Colnard, C.; Cowen, D.F.; D'Agostino, M.V.; Danninger, M.; Clercq, C. De; Demirors, L.; Depaepe, O.; Descamps, F.; Desiati, P.; Vries-Uiterweerd, G. de; DeYoung, T.; Diaz-Velez, J.C.; Dreyer, J.; Dumm, J.P.; Duvoort, M.R.; Ehrlich, R.; Eisch, J.; Ellsworth, R.W.; Engdegard, O.; Euler, S.; Evenson, P.A.; Fadiran, O.; Fazely, A.R.; Feusels, T.; Filimonov, K.; Finley, C.; Foerster, M.M.; Fox, B.D.; Franckowiak, A.; Franke, R.; Gaisser, T.K.; Gallagher, J.; Ganugapati, R.; Geisler, M.; Gerhardt, L.; Gladstone, L.; Glusenkamp, T.; Goldschmidt, A.; Goodman, J.A.; Grant, D.; Griesel, T.; Gross, A.; Grullon, S.; Gunasingha, R.M.; Gurtner, M.; Gustafsson, L.; Ha, C.; Hallgren, A.; Halzen, F.; Han, K.; Hanson, K.; Helbing, K.; Herquet, P.; Hickford, S.; Hill, G.C.; Hoffman, K.D.; Homeier, A.; Hoshina, K.; Hubert, D.; Huelsnitz, W.; Lafebre, S.J.

    2011-01-01

    Using the South Pole Acoustic Test Setup (SPATS) and a retrievable transmitter deployed in holes drilled for the IceCube experiment, we have measured the attenuation of acoustic signals by South Pole ice at depths between 190 m and 500 m. Three data sets, using different acoustic sources, have been

  15. LOFAR MSSS: detection of a low-frequency radio transient in 400 h of monitoring of the North Celestial Pole

    Science.gov (United States)

    Stewart, A. J.; Fender, R. P.; Broderick, J. W.; Hassall, T. E.; Muñoz-Darias, T.; Rowlinson, A.; Swinbank, J. D.; Staley, T. D.; Molenaar, G. J.; Scheers, B.; Grobler, T. L.; Pietka, M.; Heald, G.; McKean, J. P.; Bell, M. E.; Bonafede, A.; Breton, R. P.; Carbone, D.; Cendes, Y.; Clarke, A. O.; Corbel, S.; de Gasperin, F.; Eislöffel, J.; Falcke, H.; Ferrari, C.; Grießmeier, J.-M.; Hardcastle, M. J.; Heesen, V.; Hessels, J. W. T.; Horneffer, A.; Iacobelli, M.; Jonker, P.; Karastergiou, A.; Kokotanekov, G.; Kondratiev, V. I.; Kuniyoshi, M.; Law, C. J.; van Leeuwen, J.; Markoff, S.; Miller-Jones, J. C. A.; Mulcahy, D.; Orru, E.; Pandey-Pommier, M.; Pratley, L.; Rol, E.; Röttgering, H. J. A.; Scaife, A. M. M.; Shulevski, A.; Sobey, C. A.; Stappers, B. W.; Tasse, C.; van der Horst, A. J.; van Velzen, S.; van Weeren, R. J.; Wijers, R. A. M. J.; Wijnands, R.; Wise, M.; Zarka, P.; Alexov, A.; Anderson, J.; Asgekar, A.; Avruch, I. M.; Bentum, M. J.; Bernardi, G.; Best, P.; Breitling, F.; Brüggen, M.; Butcher, H. R.; Ciardi, B.; Conway, J. E.; Corstanje, A.; de Geus, E.; Deller, A.; Duscha, S.; Frieswijk, W.; Garrett, M. A.; Gunst, A. W.; van Haarlem, M. P.; Hoeft, M.; Hörandel, J.; Juette, E.; Kuper, G.; Loose, M.; Maat, P.; McFadden, R.; McKay-Bukowski, D.; Moldon, J.; Munk, H.; Norden, M. J.; Paas, H.; Polatidis, A. G.; Schwarz, D.; Sluman, J.; Smirnov, O.; Steinmetz, M.; Thoudam, S.; Toribio, M. C.; Vermeulen, R.; Vocks, C.; Wijnholds, S. J.; Wucknitz, O.; Yatawatta, S.

    2016-03-01

    We present the results of a four-month campaign searching for low-frequency radio transients near the North Celestial Pole with the Low-Frequency Array (LOFAR), as part of the Multifrequency Snapshot Sky Survey (MSSS). The data were recorded between 2011 December and 2012 April and comprised 2149 11-min snapshots, each covering 175 deg2. We have found one convincing candidate astrophysical transient, with a duration of a few minutes and a flux density at 60 MHz of 15-25 Jy. The transient does not repeat and has no obvious optical or high-energy counterpart, as a result of which its nature is unclear. The detection of this event implies a transient rate at 60 MHz of 3.9^{+14.7}_{-3.7}× 10^{-4} d-1 deg-2, and a transient surface density of 1.5 × 10-5 deg-2, at a 7.9-Jy limiting flux density and ˜10-min time-scale. The campaign data were also searched for transients at a range of other time-scales, from 0.5 to 297 min, which allowed us to place a range of limits on transient rates at 60 MHz as a function of observation duration.

  16. LOFAR MSSS: Detection of a low-frequency radio transient in 400 hrs of monitoring of the North Celestial Pole

    CERN Document Server

    Stewart, A J; Broderick, J W; Hassall, T E; Muñoz-Darias, T; Rowlinson, A; Swinbank, J D; Staley, T D; Molenaar, G J; Scheers, B; Grobler, T L; Pietka, M; Heald, G; McKean, J P; Bell, M E; Bonafede, A; Breton, R P; Carbone, D; Cendes, Y; Clarke, A O; Corbel, S; de Gasperin, F; Eislöffel, J; Falcke, H; Ferrari, C; Grießmeier, J -M; Hardcastle, M J; Heesen, V; Hessels, J W T; Horneffer, A; Iacobelli, M; Jonker, P; Karastergiou, A; Kokotanekov, G; Kondratiev, V I; Kuniyoshi, M; Law, C J; van Leeuwen, J; Markoff, S; Miller-Jones, J C A; Mulcahy, D; Orru, E; Pandey-Pommier, M; Pratley, L; Rol, E; Röttgering, H J A; Scaife, A M M; Shulevski, A; Sobey, C A; Stappers, B W; Tasse, C; van der Horst, A J; van Velzen, S; van Weeren, R J; Wijers, R A M J; Wijnands, R; Wise, M; Zarka, P; Alexov, A; Anderson, J; Asgekar, A; Avruch, I M; Bentum, M J; Bernardi, G; Best, P; Breitling, F; Brüggen, M; Butcher, H R; Ciardi, B; Conway, J E; Corstanje, A; de Geus, E; Deller, A; Duscha, S; Frieswijk, W; Garrett, M A; Gunst, A W; van Haarlem, M P; Hoeft, M; Hörandel, J; Juette, E; Kuper, G; Loose, M; Maat, P; McFadden, R; McKay-Bukowski, D; Moldon, J; Munk, H; Norden, M J; Paas, H; Polatidis, A G; Schwarz, D; Sluman, J; Smirnov, O; Steinmetz, M; Thoudam, S; Toribio, M C; Vermeulen, R; Vocks, C; Wijnholds, S J; Wucknitz, O; Yatawatta, S

    2015-01-01

    We present the results of a four-month campaign searching for low-frequency radio transients near the North Celestial Pole with the Low-Frequency Array (LOFAR), as part of the Multifrequency Snapshot Sky Survey (MSSS). The data were recorded between 2011 December and 2012 April and comprised 2149 11-minute snapshots, each covering 175 deg^2. We have found one convincing candidate astrophysical transient, with a duration of a few minutes and a flux density at 60 MHz of 15-25 Jy. The transient does not repeat and has no obvious optical or high-energy counterpart, as a result of which its nature is unclear. The detection of this event implies a transient rate at 60 MHz of 3.9 (+14.7, -3.7) x 10^-4 day^-1 deg^-2, and a transient surface density of 1.5 x 10^-5 deg^-2, at a 7.9-Jy limiting flux density and ~10-minute time-scale. The campaign data were also searched for transients at a range of other time-scales, from 0.5 to 297 min, which allowed us to place a range of limits on transient rates at 60 MHz as a funct...

  17. Cassini Observes the Active South Pole of Enceladus

    Science.gov (United States)

    Porco, C. C.; Helfenstein P.; Thomas, P. C.; Ingersoll, A. P.; Wisdom, J.; West, R.; Neukum, G.; Denk, T.; Wagner, R.; Roatsch, T.; Kieffer, S.; Turtle, E.; McEwen, A.; Johnson, T. V.; Rathbun, J.; Veverka, J.; Wilson, D.; Perry, J.; Spitale, J.; Brahic, A.; Burns, J. A.; DelGenio, A. D.; Dones, L.; Murray, C. D.; Squyres, S.

    2007-01-01

    Cassini has identified a geologically active province a the south pole of Saturn's moon Enceladus. The shape of Enceladus suggests a possible intense heating epoch in the past by capture into a 1:4 secondary spin/orbit resonance.

  18. Design and performance of the South Pole Acoustic Test Setup

    CERN Document Server

    Abdou, Yasser; Berdermann, Jens; Bissok, Martin; Bohm, Christian; Boeser, Sebastian; Bothe, Martin; Carson, Michael; Descamps, Freija; Fischer-Wolfarth, Jan-Hendrik; Gustafsson, Leif; Hallgren, Allan; Heinen, Dirk; Helbing, Klaus; Heller, Reinhart; Hundertmark, Stephan; Karg, Timo; Krieger, Kevin; Laihem, Karim; Meures, Thomas; Nahnhauer, Rolf; Naumann, Uwe; Oberson, Filip; Paul, Larissa; Pohl, Mario; Price, Buford; Ribordy, Mathieu; Ryckbosch, Dirk; Schunck, Matthias; Semburg, Benjamin; Stegmaier, Jutta; Sulanke, Karl-Heinz; Tosi, Delia; Vandenbroucke, Justin; Wiebusch, Christopher

    2011-01-01

    The South Pole Acoustic Test Setup (SPATS) was built to evaluate the acoustic characteristics of the South Pole ice in the 10 kHz to 100 kHz frequency range, for the purpose of assessing the feasibility of an acoustic neutrino detection array at the South Pole. The SPATS hardware consists of four vertical strings deployed in the upper 500 m of the South Pole ice cap. The strings form a trapezoidal array with a maximum baseline of 543 m. Each string has 7 stages equipped with one transmitter and one sensor module. Sound is detected or generated by piezoelectric ceramic elements inside the modules. Analogue signals are sent to the surface on electric cables where they are digitized by a PC-based data acquisition system. The data from all strings are collected on a central computer in the IceCube Laboratory from where they are send to a central data storage facility via a satellite link or stored locally on tape. A technical overview of SPATS and its performance is presented.

  19. Lunar Prospecting: Searching for Volatiles at the South Pole

    Science.gov (United States)

    Trimble, Jay; Carvalho, Robert

    2016-01-01

    The Resource Prospector is an in-situ resource utilization (ISRU) technology demonstration mission, planned for a 2021 launch to search for and analyze volatiles at the Lunar South Pole. The mission poses unique operational challenges. Operating at the Lunar South Pole requires navigating a surface with lighting, shadow and regolith characteristics unlike those of previous missions. The short round trip communications time enables reactive surface operations for science and engineering. Navigation of permanently shadowed regions with a solar powered rover creates risks, including power and thermal management, and requires constant real time decision making for safe entry, path selection and egress. The mission plan requires a faster rover egress from the lander than any previous NASA rover mission.

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

    CERN Document Server

    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.

  1. HADES - Hydrophone for Acoustic Detection at South Pole

    CERN Document Server

    Semburg, Benjamin

    2008-01-01

    The South Pole Acoustic Test Setup (SPATS) is located in the upper part of the optical neutrino observatory IceCube, currently under construction. SPATS consists of four strings at depths between 80 m and 500 m below the surface of the ice with seven stages per string. Each stage is equipped with an acoustic sensor and a transmitter. Three strings (string A-C) were deployed in the austral summer 2006/07. SPATS was extended by a fourth string (string D) with second generation sensors and transmitters in 2007/08. One second generation sensor type HADES (Hydrophone for Acoustic Detection at South Pole) consists of a ring-shaped piezo-electric element coated with polyurethane. The development of the sensor, optimization of acoustic transmission by acoustic impedance matching and first in-situ results will be discussed.

  2. The South Pole Telescope: Unraveling the Mystery of Dark Energy

    Science.gov (United States)

    Reichardt, Christian L.; de Haan, Tijmen; Bleem, Lindsey E.

    2016-07-01

    The South Pole Telescope (SPT) is a 10-meter telescope designed to survey the millimeter-wave sky, taking advantage of the exceptional observing conditions at the Amundsen-Scott South Pole Station. The telescope and its ground-breaking 960-element bolometric camera finished surveying 2500 square degrees at 95. 150, and 220 GHz in November 2011. We have discovered hundreds of galaxy clusters in the SPT-SZ survey through the Sunyaev-Zel’dovich (SZ) effect. The formation of galaxy clusters the largest bound objects in the universe is highly sensitive to dark energy and the history of structure formation. I will discuss the cosmological constraints from the SPT-SZ galaxy cluster sample as well as future prospects with the soon to-be-installed SPT-3G camera.

  3. Background studies for acoustic neutrino detection at the South Pole

    CERN Document Server

    Abbasi, R; Abu-Zayyad, T; Adams, J; Aguilar, J A; Ahlers, M; Andeen, K; Auffenberg, J; Bai, X; Baker, M; Barwick, S W; Bay, R; Alba, J L Bazo; Beattie, K; Beatty, J J; Bechet, S; Becker, J K; Becker, K -H; Benabderrahmane, M L; BenZvi, S; Berdrmann, J; Berghaus, P; Berley, D; Bernardini, E; Bertrand, D; Besson, D Z; Bindig, D; Bissok, M; Blaufuss, E; Blumenthal, J; Boersma, D J; Bohm, C; Bose, D; Böser, S; Botner, O; Braun, J; Brown, A M; Buitink, S; Carson, M; Chirkin, D; Christy, B; Clem, J; Clevermann, F; Cohen, S; Colnard, C; Cowen, D F; D'Agostino, M V; Danninger, M; Daughhetee, J; Davis, J C; De Clercq, C; Demirörs, L; Denger, T; Depaepe, O; Descamps, F; Desiati, P; de Vries-Uiterweerd, G; DeYoung, T; Diaz-Vélez, J C; Dierckxsens, M; Dreyer, J; Dumm, J P; Ehrlich, R; Eisch, J; Ellsworth, R W; Engdegård, O; Euler, S; Evenson, P A; Fadiran, O; Fazely, A R; Fedynitch, A; Feusels, T; Filimonov, K; Finley, C; Fischer-Wasels, T; Foerster, M M; Fox, B D; Franckowiak, A; Franke, R; Gaisser, T K; Gallagher, J; Geisler, M; Gerhardt, L; Gladstone, L; Glüsenkamp, T; Goldschmidt, A; Goodman, J A; Grant, D; Griesel, T; Groß, A; Grullon, S; Gurtner, M; Ha, C; Hallgren, A; Halzen, F; Han, K; Hanson, K; Heinen, D; Helbing, K; Herquet, P; Hickford, S; Hill, G C; Hoffman, K D; Homeier, A; Hoshina, K; Hubert, D; Huelsnitz, W; Hülß, J -P; Hulth, P O; Hultqvist, K; Hussain, S; Ishihara, A; Jacobsen, J; Japaridze, G S; Johansson, H; Joseph, J M; Kampert, K -H; Kappes, A; Karg, T; Karle, A; Kelley, J L; Kenny, P; Kiryluk, J; Kislat, F; Klein, S R; Köhne, J -H; Kohnen, G; Kolanoski, H; Köpke, L; Kopper, S; Koskinen, D J; Kowalski, M; Kowarik, T; Krasberg, M; Krings, T; Kroll, G; Kuehn, K; Kuwabara, T; Labare, M; Lafebre, S; Laihem, K; Landsman, H; Larson, M J; Lauer, R; Lünemann, J; Madsen, J; Majumdar, P; Marotta, A; Maruyama, R; Mase, K; Matis, H S; Meagher, K; Merck, M; Mészáros, P; Meures, T; Middell, E; Milke, N; Miller, J; Montaruli, T; Morse, R; Movit, S M; Nahnhauer, R; Nam, J W; Naumann, U; Nießen, P; Nygren, D R; Odrowski, S; Olivas, A; Olivo, M; O'Murchadha, A; Ono, M; Panknin, S; Paul, L; Heros, C Pérez de los; Petrovic, J; Piegsa, A; Pieloth, D; Porrata, R; Posselt, J; Price, P B; Prikockis, M; Przybylski, G T; Rawlins, K; Redl, P; Resconi, E; Rhode, W; Ribordy, M; Rizzo, A; Rodrigues, J P; Roth, P; Rothmaier, F; Rott, C; Ruhe, T; Rutledge, D; Ruzybayev, B; Ryckbosch, D; Sander, H -G; Santander, M; Sarkar, S; Schatto, K; Schmidt, T; Schönwald, A; Schukraft, A; Schultes, A; Schulz, O; Schunck, M; Seckel, D; Semburg, B; Seo, S H; Sestayo, Y; Seunarine, S; Silvestri, A; Slipak, A; Spiczak, G M; Spiering, C; Stamatikos, M; Stanev, T; Stephens, G; Stezelberger, T; Stokstad, R G; Stössl, A; Stoyanov, S; Strahler, E A; Straszheim, T; Stür, M; Sullivan, G W; Swillens, Q; Taavola, H; Taboada, I; Tamburro, A; Tepe, A; Ter-Antonyan, S; Tilav, S; Toale, P A; Toscano, S; Tosi, D; Turčan, D; van Eijndhoven, N; Vandenbroucke, J; Van Overloop, A; van Santen, J; Vehring, M; Voge, M; Walck, C; Waldenmaier, T; Wallraff, M; Walter, M; Weaver, Ch; Wendt, C; Westerhoff, S; Whitehorn, N; Wiebe, K; Wiebusch, C H; Williams, D R; Wischnewski, R; Wissing, H; Wolf, M; Woschnagg, K; Xu, C; Xu, X W; Yodh, G; Yoshida, S; Zarzhitsky, P

    2011-01-01

    The detection of acoustic signals from ultra-high energy neutrino interactions is a promising method to measure the tiny flux of cosmogenic neutrinos expected on Earth. The energy threshold for this process depends strongly on the absolute noise level in the target material. The South Pole Acoustic Test Setup (SPATS), deployed in the upper part of four boreholes of the IceCube Neutrino Observatory, has monitored the noise in Antarctic ice at the geographic South Pole for more than two years down to 500 m depth. The noise is very stable and Gaussian distributed. Lacking an in-situ calibration up to now, laboratory measurements have been used to estimate the absolute noise level in the 10 to 50 kHz frequency range to be smaller than 20 mPa. Using a threshold trigger, sensors of the South Pole Acoustic Test Setup registered acoustic pulse-like events in the IceCube detector volume and its vicinity. Acoustic signals from refreezing IceCube holes and from anthropogenic sources have been used to localize acoustic e...

  4. Narrow-band ELF events observed from South Pole Station

    Science.gov (United States)

    Heavisides, J.; Weaver, C.; Lessard, M.; Weatherwax, A. T.

    2012-12-01

    Extremely Low Frequency (ELF) waves are typically in the range of 3 Hz - 3 kHz and can play a role in acceleration and pitch-angle scattering of energetic particles in the radiation belts. Observations of a not uncommon, but not well studied ELF phenomenon are presented with ground-based data from South Pole Station. The narrow-band waves last approximately one or two minutes maintaining bandwidth over the course of the event, begin around 100 Hz, decrease to about 70 Hz, and typically show a higher frequency harmonic. The waves have only been documented at four locations - Heacock, 1974 (Alaska); Sentman and Ehring, 1994 (California); Wang et al, 2005 and Wang et al, 2011 (Taiwan); and Kim et al, 2006 (South Pole). The waves observed at the South Pole are not detected when the Sun drops below a 10 degree elevation angle, which is not true for the other locations. We extend the study of Kim et al, 2006, and explore possible generation mechanisms including sunlit ionosphere and ion cyclotron wave modes, as well as correspondence with energetic particle precipitation.

  5. Autumn at Titan's South Pole: The 220 cm-1 Cloud

    Science.gov (United States)

    Jennings, D. E.; Cottini, V.; Achterberg, R. K.; Anderson, C. M.; Flasar, F. M.; de Kok, R. J.; Teanby, N. A.; Coustenis, A.; Vinatier, S.

    2015-10-01

    Beginning in 2012 an atmospheric cloud known by its far-infrared emission has formed rapidly at Tit an's South Pole [1, 2]. The build-up of this condensate is a result of deepening temperatures and a gathering of gases as Winter approaches. Emission from the cloud in the south has been doubling each year since 2012, in contrast to the north where it has halved every 3.8 years since 2004. The morphology of the cloud in the south is quite different from that in the north. In the north, the cloud has extended over the whole polar region beyond 55 N, whereas in the south the cloud has been confined to within about 10 degrees of the pole. The cloud in the north has had the form of a uniform hood, whereas the southern cloud has been much more complex. A map from December 2014,recorded by the Composite Infrared Spectrometer (CIRS) on Cassini, showed the 220 cm-1 emission coming from a distinct ring with a maximum at about 80 S. In contrast, emissions from the gases HC3N, C4H2 and C6H6 peaked near the pole and had a ring at 70 S. The 220 cm-1 ring at 80 S coincided with the minimum in the gas emission pattern. The80 S condensate ring encompassed the vortex cloud seen by the Cassini Imaging Science Subsystem (ISS) and Visible and Infrared Mapping Spectrometer (VIMS)[3, 4]. Both the 220 cm-1 ring and the gas "bull's-eye" pattern were centered on a point that was shifted from the geographic South Pole by 4 degrees in the direction of the Sun. This corresponds to the overall tilt of Titan's atmosphere discovered from temperature maps early in the Cassini mission by Achterberg et al. [5]. The tilt may be reinforced by the presumably twice-yearly (north and south) spin-up of the atmosphere at the autumnal pole. The bull's-eye pattern of the gas emissions can be explained by the retrieved abundance distributions, which are maximum near the pole and decrease sharply toward lower latitudes, together with temperatures that are minimum at the pole and increase toward lower latitudes

  6. Distribution and anomaly of microwave emission at Lunar South Pole

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Investigation on Lunar polar area is almost every lunar mission’s primary objective in recent years. The rationale behind it is that illumination and ice resources in this area can be potentially very helpful for constructing lunar human base. In this paper, we analyze microwave radiometric characteristics of the Moon by using the newly acquired Chang’E-1 Lunar Microwave Sounder (CELMS) data. Microwave brightness temperature at Lunar South Pole (LSP) is distributed regularly with a style of "ring-in-ring", decreasing from equator to pole. Regolith temperature gradient is bigger at lunar equator than at polar area. Brightness temperature diurnal difference decreases with observation frequency. Microwave brightness temperature distribution maps at LSP and Lunar North Pole (LNP) have been made based on the analysis. It is found that microwave brightness temperature becomes to synchronize with elevation beyond -85° latitude. This phenomenon is related to lightening condition and indicates temperature distribution at LSP. The brightness temperature anomaly cold points are potentially cold trap areas for water or ice while hot points imply plenty of illumination resources there.

  7. Submillimeter Astronomy from the South Pole (AST/RO)

    Science.gov (United States)

    Stark, Antony A.

    2013-01-01

    The Antarctic Submillimeter Telescope and Remote Observatory (AST/RO), a 1.7 m diameter offset Gregorian telescope for astronomy and aeronomy studies at wavelengths between 200 and 2000 μm, saw first light in 1995 and operated until 2005. It was the first radio telescope to operate continuously throughout the winter on the Antarctic Plateau. It served as a site testing instrument and prototype for later instruments, as well as executing a wide variety of scientific programs that resulted in six doctoral theses and more than one hundred scientific publications. 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. Especially significant are the exceptionally low values of sky noise found at this site, a result of the small water vapor content of the atmosphere. Multiple submillimeter-wave and Terahertz detector systems were in operation on AST/RO, including heterodyne and bolometric arrays. AST/RO's legacy includes comprehensive submillimeter-wave site testing of the South Pole, spectroscopic studies of 492 GHz and 809 GHz neutral atomic carbon and 460 GHz and 806 GHz carbon monoxide in the Milky Way and Magellanic Clouds, and the first detection of the 1.46 THz [N II] line from a ground-based observatory.

  8. Acoustic detection of astrophysical neutrinos in South Pole ice

    CERN Document Server

    Vandenbroucke, Justin

    2012-01-01

    When high-energy particles interact in dense media to produce a particle shower, most of the shower energy is deposited in the medium as heat. This causes the medium to expand locally and emit a shock wave with a medium-dependent peak frequency on the order of 10 kHz. In South Pole ice in particular, the elastic properties of the medium have been theorized to provide good coupling of particle energy to acoustic energy. The acoustic attenuation length has been theorized to be several km, which could enable a sparsely instrumented large-volume detector to search for rare signals from high-energy astrophysical neutrinos. We simulated a hybrid optical/radio/acoustic extension to the IceCube array, specifically intended to detect cosmogenic (GZK) neutrinos with multiple methods simultaneously in order to achieve high confidence in a discovered signal and to measure angular, temporal, and spectral distributions of GZK neutrinos. This work motivated the design, deployment, and operation of the South Pole Acoustic Te...

  9. Foregrounds for observations of the cosmological 21 cm line: II. Westerbork observations of the fields around 3C196 and the North Celestial Pole

    CERN Document Server

    Bernardi, G; Brentjens, M A; Ciardi, B; Jelić, V; Koopmans, L V E; Labropoulos, P; Offringa, A; Pandey, V N; Schaye, J; Thomas, R M; Yatawatta, S; Zaroubi, S

    2010-01-01

    In the coming years a new insight into galaxy formation and the thermal history of the Universe is expected to come from the detection of the highly redshifted cosmological 21 cm line. The cosmological 21 cm line signal is buried under Galactic and extragalactic foregrounds which are likely to be a few orders of magnitude brighter. Strategies and techniques for effective subtraction of these foreground sources require a detailed knowledge of their structure in both intensity and polarization on the relevant angular scales of 1-30 arcmin. We present results from observations conducted with the Westerbork telescope in the 140-160 MHz range with 2 arcmin resolution in two fields located at intermediate Galactic latitude, centred around the bright quasar 3C196 and the North Celestial Pole. They were observed with the purpose of characterizing the foreground properties in sky areas where actual observations of the cosmological 21 cm line could be carried out. The polarization data were analysed through the rotatio...

  10. Position of the South Magnetic Pole, January 1986

    Science.gov (United States)

    Barton, C. E.

    The present location of the South Magnetic Pole (SMP) in the southern ocean provides an opportunity to determine its position well removed from local (coastal) anomalies. An experiment is being conducted jointly by the Australian Bureau of Mineral Resources and Antarctic Division, Department of Science to make direct shipboard observations of the position and daily motion of the SMP. The technique involves determination of the horizontal component of the field (H) by using a gimbal-mounted three-axis fluxgate magnetometer. First-order compensation for the magnetic effects of the vessel is provided by a system of Helmholtz coils. During observations, the vessel is spun about a vertical axis so that any residual horizontal field due to the vessel can be eliminated by integration along two horizontal axes fixed in space.

  11. Lunar South Pole space water extraction and trucking system

    Energy Technology Data Exchange (ETDEWEB)

    Zuppero, A. [Lockheed Martin Idaho Technologies Co., Idaho Falls, ID (United States). Idaho National Engineering and Environmental Lab.]|[Univ. of Idaho, Moscow, ID (United States); Zupp, G. [National Aeronautics and Space Administration, Houston, TX (United States). Johnson Space Center; Schnitzler, B.; Larson, T.K.; Rice, J.W. [Lockheed Martin Idaho Technologies Co., Idaho Falls, ID (United States). Idaho National Engineering and Environmental Lab.

    1998-03-01

    This concept proposes to use thermal processes alone to extract water from the lunar South Pole and launch payloads to low lunar orbit. Thermal steam rockets would use water propellant for space transportation. The estimated mass of a space water tanker powered by a nuclear heated steam rocket suggests it can be designed for launch in the Space Shuttle bay. The performance depends on the feasibility of a nuclear reactor rocket engine producing steam at 1,100 degrees Kelvin, with a power density of 150 Megawatts per ton of rocket, and operating for thousands of 20 minute cycles. An example uses reject heat from a small nuclear electric power supply to melt 17,800 tons per year of lunar ice. A nuclear heated steam rocket would use the propellant water to launch and deliver 3,800 tons of water per year to a 100 km low lunar orbit.

  12. Regionalized Lunar South Pole Surface Navigation System Analysis

    Directory of Open Access Journals (Sweden)

    Bryan W. Welch

    2008-01-01

    Full Text Available Apollo missions utilized Earth-based assets for navigation, since the landings took place at lunar locations in constant view from the Earth. The new exploration campaign to the lunar South Pole region will have limited Earth visibility, but the extent to which a navigation system comprised solely of Earth-based tracking stations will provide adequate navigation solutions in this region is unknown. This article presents a dilution-of-precision-(DoP- based stationary surface navigation analysis of the performance of multiple lunar satellite constellations, Earth-based deep space network assets, and combinations thereof. Results show that kinematic and integrated solutions cannot be provided by the Earth-based deep space network stations. Also, the surface stationary navigation system needs to be operated as a two-way navigation system, or as a one-way navigation system with local terrain information, while integrating the position solution over a short duration of time with navigation signals being provided by a lunar satellite constellation.

  13. GASP II: A new-generation instrument for the gamma ray astronomy at the south pole

    International Nuclear Information System (INIS)

    An imaging version of an air Cherenkov telescope for the south pole is described. Having accrued a few years experience operating an air Cherenkov prototype detector installed at the south pole, we are confident about the possibility of installing an advanced version. The final system will be formed by an array of seven identical telescopes, arranged on the corners of a hexagon and one in the center. (orig.)

  14. Design, modeling and testing of the Askaryan Radio Array South Pole autonomous renewable power stations

    Energy Technology Data Exchange (ETDEWEB)

    Besson, D.Z., E-mail: zedlam@ku.edu [Department of Physics and Astronomy, University of Kansas, 1082 Malott Hall, 1251 Wescoe Hall Drive, Lawrence, KS 66045-7582 (United States); Moscow Engineering and Physics Institute, 31 Kashirskaya Highway, Moscow 115409 (Russian Federation); Kennedy, D.M., E-mail: dmkennedy@ku.edu [Department of Physics and Astronomy, University of Kansas, 1082 Malott Hall, 1251 Wescoe Hall Drive, Lawrence, KS 66045-7582 (United States); Ratzlaff, K., E-mail: ratzlaff@ku.edu [Instrumentation Design Laboratory, University of Kansas, 6042 Malott Hall, 1251 Wescoe Hall Drive, Lawrence, KS 66045-7582 (United States); Young, R., E-mail: rwyoung@ku.edu [Instrumentation Design Laboratory, University of Kansas, 6042 Malott Hall, 1251 Wescoe Hall Drive, Lawrence, KS 66045-7582 (United States)

    2014-11-01

    We describe the design, construction and operation of the Askaryan Radio Array (ARA) Autonomous Renewable Power Stations, initially installed at the South Pole in December, 2010 with the goal of providing an independently operating 100 W power source capable of year-round operation in extreme environments. In addition to particle astrophysics applications at the South Pole, such a station can easily be, and has since been, extended to operation elsewhere, as described herein.

  15. Sample Return Mission to the South Pole Aitken Basin

    Science.gov (United States)

    Duke, M. B.; Clark, B. C.; Gamber, T.; Lucey, P. G.; Ryder, G.; Taylor, G. J.

    1999-01-01

    The South Pole Aitken Basin (SPA) is the largest and oldest observed feature on the Moon. Compositional and topographic data from Galileo, Clementine, and Lunar Prospector have demonstrated that SPA represents a distinctive major lunar terrane, which has not been sampled either by sample return missions (Apollo, Luna) or by lunar meteorites. The floor of SPA is characterized by mafic compositions enriched in Fe, Ti, and Th in comparison to its surroundings. This composition may represent melt rocks from the SPA event, which would be mixtures of the preexisting crust and mantle rocks. However, the Fe content is higher than expected, and the large Apollo basin, within SPA, exposes deeper material with lower iron content. Some of the Fe enrichment may represent mare and cryptomare deposits. No model adequately accounts for all of the characteristics of the SPA and disagreements are fundamental. Is mantle material exposed or contained as fragments in melt rock and breccias? If impact melt is present, did the vast sheet differentiate? Was the initial mantle and crust compositionally different from other regions of the Moon? Was the impact event somehow peculiar, (e.g., a low-velocity impact)? The precise time of formation of the SPA is unknown, being limited only by the initial differentiation of the Moon and the age of the Imbrium event, believed to be 3.9 b.y. The questions raised by the SPA can be addressed only with detailed sample analysis. Analysis of the melt rocks, fragments in breccias, and basalts of SPA can address several highly significant problems for the Moon and the history of the solar system. The time of formation of SPA, based on analysis of melt rocks formed in the event. would put limits on the period of intense bombardment of the Moon, which has been inferred by some to include a "terminal cataclysm." If close to 3.9 Ga, the presumed age of the Imbrium Basin, the SPA date would confirm the lunar cataclysm. This episode, if it occurred, would have

  16. Submillimeter Atmospheric Transparency at Maunakea, at the South Pole, and at Chajnantor

    Science.gov (United States)

    Radford, Simon J. E.; Peterson, Jeffery B.

    2016-07-01

    For a systematic assessment of submillimeter observing conditions at different sites, we constructed tipping radiometers to measure the broad band atmospheric transparency in the window around 350 μm wavelength. The tippers were deployed on Maunakea, Hawaii, at the South Pole, and in the vicinity of Cerro Chajnantor in northern Chile. Identical instruments permit direct comparison of these sites. Observing conditions at the South Pole and in the Chajnantor area are better than on Maunakea. Simultaneous measurements with two tippers demonstrate conditions at the summit of Cerro Chajnantor are significantly better than on the Chajnantor plateau.

  17. South Pole glacial climate reconstruction from multi-borehole laser particulate stratigraphy

    OpenAIRE

    Aguilar Sanchez, Juan; Christov, Asen; Montaruli, Teresa; Rameez, Mohamed; IceCube Collaboration

    2013-01-01

    The IceCube Neutrino Observatory and its prototype, AMANDA, were built in South Pole ice, using powerful hot-water drills to cleanly bore >100 holes to depths up to 2500 m. The construction of these particle physics detectors provided a unique opportunity to examine the deep ice sheet using a variety of novel techniques. We made high-resolution particulate profiles with a laser dust logger in eight of the boreholes during detector commissioning between 2004 and 2010. The South Pole laser logs...

  18. Comparison of UV irradiance measurements at Summit, Greenland; Barrow, Alaska; and South Pole, Antarctica

    Directory of Open Access Journals (Sweden)

    G. Bernhard

    2008-08-01

    Full Text Available An SUV-150B spectroradiometer for measuring solar ultraviolet (UV irradiance was installed at Summit, Greenland, in August 2004. Here we compare the initial data from this new location with similar measurements from Barrow, Alaska, and South Pole. Measurements of irradiance at 345 nm performed at equivalent solar zenith angles (SZAs are almost identical at Summit and South Pole. The good agreement can be explained with the similar location of the two sites on high-altitude ice caps with high surface albedo. Clouds attenuate irradiance at 345 nm at both sites by less than 6% on average, but can reduce irradiance at Barrow by more than 75%. Clear-sky measurements at Barrow are smaller than at Summit by 14% in spring and 36% in summer, mostly due to differences in surface albedo and altitude. Comparisons with model calculations indicate that aerosols can reduce clear-sky irradiance at Summit by 4–6%; aerosol influence is largest in April. Differences in total ozone at the three sites have a large influence on the UV Index. At South Pole, the UV Index is on average 20–80% larger during the ozone hole period than between January and March. At Summit, total ozone peaks in April and UV Indices in spring are on average 10–25% smaller than in the summer. Maximum UV Indices ever observed at Summit, Barrow, and South Pole are 6.7, 5.0, and 4.0, respectively. The larger value at Summit is due to the site's lower latitude. For comparable SZAs, average UV Indices measured during October and November at South Pole are 1.9–2.4 times larger than measurements during March and April at Summit. Average UV Indices at Summit are over 50% greater than at Barrow because of the larger cloud influence at Barrow.

  19. North Pole, South Pole: the quest to understand the mystery of Earth's magnetism

    Science.gov (United States)

    Turner, G. M.

    2010-12-01

    The story of the quest to understand Earth’s magnetic field is one of the longest and richest in the history of science. It weaves together Greek philosophy, Chinese mysticism, the development of the compass and navigation, the physics of electromagnetism and the jig-saw like piecing together of the internal structure of the planet beneath our feet. The story begins with Magnes, an old shepherd, trudging up the mountainside after a violent thunder storm, astonished at how the iron studs in his boots stick to the rocks. It was Alexander von Humboldt who, three millennia on, pointed to lightning as the source of such magnetization. The first compass was made 2000 years ago in China - to divine the ways of feng shui - a guide to planting crops, planning streets, orienting buildings and more. It reached Europe as a navigational tool in the 12th century - no-one is quite sure how, but en route it changed from south-pointing to the north-pointing compasses of today. The earliest truly scientific experiments and writings concerned magnets and geomagnetism: Petrus Peregrinus’ Epistola of 1269, and William Gilbert’s De Magnete of1600, in which he declared Magnus magnes globus terrestris ipse est - the Earth itself is a great magnet. By then it was recognized that the compass didn’t point exactly north, and the discrepancy varied from place to place and changed over time - something of a problem for Gilbert’s idea of a geocentric axial dipole. However declination and secular variation were problems well known to Edmund Halley, who, in 1700, charted the angle of declination over the Atlantic Ocean, and in the process introduced the Halleyan line - the contour. Many of the world’s greatest scientists have turned their minds to the problem of magnetism and geomagnetism in particular - Coulomb, Gauss, Faraday, Maxwell - yet in 1905, Einstein described geomagnetism as “one of the great unsolved problems of physics”. In the mid-late nineteenth century new areas of

  20. Celestial Treasury

    Science.gov (United States)

    Lachièze-Rey, Marc; Luminet, Jean-Pierre

    2001-07-01

    Throughout history, the mysterious dark skies have inspired our imaginations in countless ways, influencing our endeavors in science and philosophy, religion, literature, and art. Filled with 380 full-color illustrations, Celestial Treasury shows the influence of astronomical theories and the richness of illustrations in Western civilization through the ages. The authors explore the evolution of our understanding of astronomy and weave together ancient and modern theories in a fascinating narrative. They incorporate a wealth of detail from Greek verse, medieval manuscripts and Victorian poetry with contemporary spacecraft photographs and computer-generated star charts. Celestial Treasury is more than a beautiful book: it answers a variety of questions that have intrigued scientists and laymen for centuries. -- How did philosophers and scientists try to explain the order that governs celestial motion? -- How did geometers and artists measure and map the skies? -- How many different answers have been proposed for the most fundamental of all questions: When and how did Earth come about? -- Who inhabits the heavens--gods, angels or extraterrestrials? No other book recounts humankind's fascination with the heavens as compellingly as Celestial Treasury. Marc Lachièze-Rey is a director of research at the Centre National pour la Récherche Scientifique and astrophysicist at the Centre d'Etudes de Saclay. He is the author of The Cosmic Background Radiation (Cambridge, 1999), and and The Quest for Unity, (Oxford, 1999 ), as well as many books in French. Jean-Pierre Luminet is a research director of the Centre National pour la Rechérche Scientifique, based at the Paris-Meudon observatory. He is the author of Black Holes, (Cambridge 1992), as well as science documentaries for television.

  1. Transient eastward-propagating long-period waves observed over the South Pole

    Directory of Open Access Journals (Sweden)

    S. E. Palo

    Full Text Available Observations of the horizontal wind field over the South Pole were made during 1995 using a meteor radar. These data have revealed the presence of a rich spectrum of waves over the South Pole with a distinct annual occurrence. Included in this spectrum are long-period waves, whose periods are greater than one solar day, which are propagating eastward. These waves exhibit a distinct seasonal occurrence where the envelope of wave periods decreases from a period of 10 days near the fall equinox to a minimum of 2 days near the winter solstice and then progresses towards a period near 10 days at the spring equinox. Computation of the meridional gradient of quasi-geostrophic potential vorticity has revealed a region in the high-latitude upper mesosphere which could support an instability and serve as a source for these waves. Estimation of the wave periods which would be generated from an instability in this region closely resembles the observed seasonal variation in wave periods over the South Pole. These results are consistent with the hypothesis that the observed eastward propagating long-period waves over the South Pole are generated by an instability in the polar upper mesosphere. However, given our limited data set we cannot rule out a stratospheric source. Embedded in this spectrum of eastward propagating waves during the austral winter are a number of distinct wave events. Eight such wave events have been identified and localized using a constant-Q filter bank. The periods of these wave events ranges from 1.7 to 9.8 days and all exist for at least 3 wave periods. Least squares analysis has revealed that a number of these events are inconsistent with a wave propagating zonally around the geographic pole and could be related to waves propagating around a dynamical pole which is offset from the geographic pole. Additionally, one event which was observed appears to be a standing oscillation.

    Key words. Meteorology and atmospheric

  2. The Spitzer-South Pole Telescope Deep Field: Survey Design and IRAC Catalogs

    CERN Document Server

    Ashby, M L N; Brodwin, M; Gonzalez, A H; Martinez, J; Bartlett, J G; Benson, B A; Bleem, L E; Crawford, T M; Dey, A; Dressler, A; Eisenhardt, P R M; Galametz, A; Jannuzi, B T; Marrone, D P; Mei, S; Muzzin, A; Pacaud, F; Pierre, M; Stern, D; Vieira, J D

    2013-01-01

    The Spitzer-South Pole Telescope Deep Field (SSDF) is a wide-area survey using Spitzer's Infrared Array Camera (IRAC) to cover 94 square degrees of extragalactic sky, making it the largest IRAC survey completed to date outside the Milky Way midplane. The SSDF is centered at 23:30,-55:00, in a region that combines observations spanning a broad wavelength range from numerous facilities. These include millimeter imaging from the South Pole Telescope, far-infrared observations from Herschel/SPIRE, X-ray observations from the XMM XXL survey, near-infrared observations from the VISTA Hemisphere Survey, and radio-wavelength imaging from the Australia Telescope Compact Array, in a panchromatic project designed to address major outstanding questions surrounding galaxy clusters and the baryon budget. Here we describe the Spitzer/IRAC observations of the SSDF, including the survey design, observations, processing, source extraction, and publicly available data products. In particular, we present two band-merged catalogs...

  3. Status and recent results of the South Pole Acoustic Test Setup

    CERN Document Server

    Karg, Timo

    2010-01-01

    The South Pole Acoustic Test Setup (SPATS) has been deployed to study the feasibility of acoustic neutrino detection in Antarctic ice around the South Pole. An array of four strings equipped with acoustic receivers and transmitters, permanently installed in the upper 500 m of boreholes drilled for the IceCube neutrino observatory, and a retrievable transmitter that can be used in the water filled holes before the installation of the IceCube optical strings are used to measure the ice acoustic properties. These include the sound speed and its depth dependence, the attenuation length, the noise level, and the rate and nature of transient background sources in the relevant frequency range from 10 kHz to 100 kHz. SPATS is operating successfully since January 2007 and has been able to either measure or constrain all parameters. We present the latest results of SPATS and discuss their implications for future acoustic neutrino detection activities in Antarctica.

  4. Celestial Burial Masters

    Institute of Scientific and Technical Information of China (English)

    YUQIAN

    2004-01-01

    Celestial burial is worshipped in Tibet as the highest pursuit of life. Of three elements indispensable for celestial burial-celestial rock (also known as altar), cinereous vultures, and masters of celestial burial, celestial burial masters are the most mysteriously important.

  5. On the mystery of the perennial carbon dioxide cap at the south pole of Mars

    OpenAIRE

    Guo, Xin; Richardson, Mark Ian; Soto, Alejandro; Toigo, Anthony

    2010-01-01

    A perennial ice cap has long been observed near the south pole of Mars. The surface of this cap is predominantly composed of carbon dioxide ice. The retention of a CO_2 ice cap results from the surface energy balance of the latent heat, solar radiation, surface emission, subsurface conduction, and atmospheric sensible heat. While models conventionally treat surface CO_2 ice using constant ice albedos and emissivities, such an approach fails to predict the existence of a perennial cap. Here we...

  6. Measurement of sound speed vs. depth in South Pole ice: pressure waves and shear waves

    Energy Technology Data Exchange (ETDEWEB)

    IceCube Collaboration; Klein, Spencer

    2009-06-04

    We have measured the speed of both pressure waves and shear waves as a function of depth between 80 and 500 m depth in South Pole ice with better than 1% precision. The measurements were made using the South Pole Acoustic Test Setup (SPATS), an array of transmitters and sensors deployed in the ice at the South Pole in order to measure the acoustic properties relevant to acoustic detection of astrophysical neutrinos. The transmitters and sensors use piezoceramics operating at {approx}5-25 kHz. Between 200 m and 500 m depth, the measured profile is consistent with zero variation of the sound speed with depth, resulting in zero refraction, for both pressure and shear waves. We also performed a complementary study featuring an explosive signal propagating vertically from 50 to 2250 m depth, from which we determined a value for the pressure wave speed consistent with that determined for shallower depths, higher frequencies, and horizontal propagation with the SPATS sensors. The sound speed profile presented here can be used to achieve good acoustic source position and emission time reconstruction in general, and neutrino direction and energy reconstruction in particular. The reconstructed quantities could also help separate neutrino signals from background.

  7. Methods of celestial mechanics

    CERN Document Server

    Brouwer, Dirk

    2013-01-01

    Methods of Celestial Mechanics provides a comprehensive background of celestial mechanics for practical applications. Celestial mechanics is the branch of astronomy that is devoted to the motions of celestial bodies. This book is composed of 17 chapters, and begins with the concept of elliptic motion and its expansion. The subsequent chapters are devoted to other aspects of celestial mechanics, including gravity, numerical integration of orbit, stellar aberration, lunar theory, and celestial coordinates. Considerable chapters explore the principles and application of various mathematical metho

  8. BICEP2/SPUD: Searching for Inflation with Degree Scale Polarimetry from the South Pole

    Science.gov (United States)

    Nguyen, Hien Trong; Kovac, John; Adec, Peter; Aikin, Randol; Benton, Steve; Bock, Jamie; Brevik, Justus; Carlstrom, John; Dowell, Darren; Duband, Lionel; Golwala, Sunil; Halpern, Mark; Hasselfield, Matthew; Irwin, Kent; Jones, William; Kaufman, Jonathan; Keating, Brian; Kuo, Chao-Lin; Lange, Andrew; Matsumura, Tomotake; Netterfield, Barth; Pryke, Clem; Ruhl, John; Sheehy, Chris; Sudiwala, Rashmi

    2008-01-01

    BICEP2/SPUD is the new powerful upgrade of the existing BICEP1 experiment, a bolometric receiver to study the polarization of the cosmic microwave background radiation, which has been in operation at the South Pole since January 2006. BICEP2 will provide an improvement up to 10 times mapping speed at 150 GHz compared to BICEP1, using the same BICEP telescope mount. SPUD, a series of compact, mechanically-cooled receivers deployed on the DASI mount at the Pole, will provide similar mapping speed in to BICEP2 in three bands, 100, 150, and 220 GHz. The new system will use large TES focal plane arrays to provide unprecedented sensitivity and excellent control of foreground contamination.

  9. Characteristics of immersion freezing nuclei at the south pole station in Antarctica

    OpenAIRE

    Ardon-Dryer, K.; Levin, Z.; R. P. Lawson

    2011-01-01

    The effectiveness of aerosols as immersion freezing nuclei at the South Pole station was investigated during January and February 2009 using the FRIDGE-TAU. The analysis consisted of testing the freezing temperature of about 100–130 drops per sample containing aerosols collected at ground level and on a balloon lifted to different heights. All the drops froze between −18 °C and −27 °C. The temperature in which 50% of the drops froze occurred at −24 °C, while...

  10. Characteristics of immersion freezing nuclei at the South Pole station in Antarctica

    OpenAIRE

    Ardon-Dryer, K.; Levin, Z.; R. P. Lawson

    2011-01-01

    The effectiveness of aerosols as immersion freezing nuclei at the South Pole station was investigated during January and February 2009 using the FRIDGE-TAU. The analysis consisted of testing the freezing temperature of about 100–130 drops per sample containing aerosols collected at ground level and on a balloon lifted to different heights. All the drops froze between −18 °C and −27 °C. The temperature in which 50 % of the drops froze occurred at −24 °C, while nuc...

  11. Solar irradiance at the earth's surface: long-term behavior observed at the South Pole

    OpenAIRE

    J. E. Frederick; A. L. Hodge

    2011-01-01

    This research examines a 17-year database of UV-A (320–400 nm) and visible (400–600 nm) solar irradiance obtained by a scanning spectroradiometer located at the South Pole. The goal is to define the variability in solar irradiance reaching the polar surface, with emphasis on the influence of cloudiness and on identifying systematic trends and possible links to the solar cycle. To eliminate changes associated with the varying solar elevation, the analysis focuses on data averaged over 30–35 da...

  12. Surveying the South Pole-Aitken basin magnetic anomaly for remnant impactor metallic iron

    Science.gov (United States)

    Cahill, Joshua T.S.; Hagerty, Justin J.; Lawrence, David M.; Klima, Rachel L.; Blewett, David T.

    2014-01-01

    The Moon has areas of magnetized crust ("magnetic anomalies"), the origins of which are poorly constrained. A magnetic anomaly near the northern rim of South Pole-Aitken (SPA) basin was recently postulated to originate from remnant metallic iron emplaced by the SPA basin-forming impactor. Here, we remotely examine the regolith of this SPA magnetic anomaly with a combination of Clementine and Lunar Prospector derived iron maps for any evidence of enhanced metallic iron content. We find that these data sets do not definitively detect the hypothesized remnant metallic iron within the upper tens of centimeters of the lunar regolith.

  13. Mach-Zehnder Modulator Performance on the NIF South Pole Bang Time Diagnostic

    Energy Technology Data Exchange (ETDEWEB)

    Beeman, B.; MacPhee, A. G.; Kimbrough, J. R.; Chow, R.; Carpenter, A.; Bond, E.; Zayas-Rivera, Z.; Bell, P.; Celeste, J.; Clancy, T.; Miller, E. K.; Edgell, D.; Donaldson, W. R.

    2013-09-01

    We present performance data for Mach-Zehnder optical modulators fielded on the National Ignition Facility (NIF) as a potential signal path upgrade for the South Pole Bang Time diagnostic. A single channel demonstration system has been deployed utilizing two modulators operating in a 90-degree In phase and Quadrature (I/Q) configuration. X-ray target emission signals are split and fed into two recording systems: a reference CRT based oscilloscope, Greenfield FTD10000, and the dual Mach-Zehnder system. Results of X-ray implosion time (bang time) determination from these two recording systems are compared and presented.

  14. On the age vs depth and optical clarity of deep ice at South Pole

    OpenAIRE

    the AMANDA Collaboration

    1995-01-01

    The first four strings of phototubes for the AMANDA high-energy neutrino observatory are now frozen in place at a depth of 800 to 1000 m in ice at the South Pole. During the 1995-96 season an additional six strings will be deployed at greater depths. Provided absorption, scattering, and refraction of visible light are sufficiently small, the trajectory of a muon into which a neutrino converts can be determined by using the array of phototubes to measure the arrival times of \\v{C}erenkov light...

  15. On the age vs depth and optical clarity of deep ice at South Pole

    CERN Document Server

    Askebjer, P; Bergström, L; Bouchta, A; Carius, S; Coulthard, A; Engel, K; Erlandsson, B; Goobar, A; Gray, L; Hallgren, A; Halzen, F; Hulth, O P; Jacobsen, J; Johansson, S; Kandhadai, V; Liubarsky, I; Lowder, D M; Miller, T; Mock, P; Morse, R; Porrata, R; Price, P B; Richards, A; Rubinstein, H; Spang, J C; Sun, Q; Tilav, S; Walck, C; Yodh, G

    1995-01-01

    The first four strings of phototubes for the AMANDA high-energy neutrino observatory are now frozen in place at a depth of 800 to 1000 m in ice at the South Pole. During the 1995-96 season an additional six strings will be deployed at greater depths. Provided absorption scattering, and refraction of visible light are sufficiently small, the trajectory of a muon into which a neutrino converts can be determined by using the array of phototubes to measure the arrival times of \\v{C}erenkov light emitted by the muon. To help in deciding on the depth for implantation of the six new strings, we discuss models of age vs depth for South Pole ice, we estimate mean free paths for scattering from bubbles and dust as a function of depth, and we assess distortion of light paths due to refraction at crystal boundaries and interfaces between air-hydrate inclusions and normal ice. We conclude that the depth interval 1600 to 1800 m will be suitably transparent for the next six AMANDA strings and, moreover, that the interval 16...

  16. A cylindrical current sheet over the South solar pole observed by Ulysses

    Science.gov (United States)

    Khabarova, Olga; Kislov, Roman; Malova, Helmi; Obridko, Vladimir

    2016-04-01

    We provide the first evidence for the existence of a quasi-stable cylindrical current sheet over the South solar pole as observed by Ulysses in 2006, near the solar minimum, when it reached maximal heliolatitude of 79.7 degrees at 2.4 AU. It took place inside a fast speed stream from the coronal hole, and the tube was presumably crossed rather far from the center within two degrees of heliolatitude and ~10 degrees of heliolongitude. During the spacecraft passage throughout the structure, the solar wind velocity was approximately twice as little, the solar wind density was 20 times lower than the surrounded plasma values, but the temperature was twice as large in the point closest to the pole. The interplanetary magnetic field (IMF) strongly decreased due to sharp variations in the IMF radial component (RTN) that changed its sign twice, but other components did not show changes out of usual stochastic behavior. Both the behavior of the IMF, rotation of the plasma flow direction and other features indicate the occurrence of cylindrical current sheet. We discuss its solar origin and present modeling that can explain the observations.

  17. Characteristics of immersion freezing nuclei at the South Pole station in Antarctica

    Directory of Open Access Journals (Sweden)

    K. Ardon-Dryer

    2011-04-01

    Full Text Available The effectiveness of aerosols as immersion freezing nuclei at the South Pole station was investigated during January and February 2009 using the FRIDGE-TAU. The analysis consisted of testing the freezing temperature of about 100–130 drops per sample containing aerosols collected at ground level and on a balloon lifted to different heights. All the drops froze between −18 °C and −27 °C. The temperature in which 50 % of the drops froze occurred at −24 °C, while nuclei concentration of 1 L−1 at −23 °C was calculated. Meteorological conditions such as wind speed, ice precipitation as well as the trajectories of the air masses affected the ice nuclei concentrations. Higher concentrations were observed on days when the winds were stronger or when the air mass originated from the sea.

  18. Characteristics of immersion freezing nuclei at the South Pole station in Antarctica

    Science.gov (United States)

    Ardon-Dryer, K.; Levin, Z.; Lawson, R. P.

    2011-04-01

    The effectiveness of aerosols as immersion freezing nuclei at the South Pole station was investigated during January and February 2009 using the FRIDGE-TAU. The analysis consisted of testing the freezing temperature of about 100-130 drops per sample containing aerosols collected at ground level and on a balloon lifted to different heights. All the drops froze between -18 °C and -27 °C. The temperature in which 50 % of the drops froze occurred at -24 °C, while nuclei concentration of 1 L-1 at -23 °C was calculated. Meteorological conditions such as wind speed, ice precipitation as well as the trajectories of the air masses affected the ice nuclei concentrations. Higher concentrations were observed on days when the winds were stronger or when the air mass originated from the sea.

  19. BLAST Observations of the South Ecliptic Pole field: Number Counts and Source Catalogs

    CERN Document Server

    Valiante, Elisabetta; Bock, James; Braglia, Filiberto; Chapin, Edward; Devlin, Mark Joseph; Griffin, Matthew; Gundersen, Joshua; Halpern, Mark; Hargrave, Peter; Hughes, David; Klein, Jeff; Marsden, Gaelen; Mauskopf, Philip; Netterfield, Calvin; Olmi, Luca; Pascale, Enzo; Patanchon, Guillaume; Rex, Marie; Scott, Douglas; Scott, Kimberly; Semisch, Christopher; Stabenau, Hans; Thomas, Nicholas; Truch, Matthew; Tucker, Carole; Tucker, Gregory; Viero, Marco; Wiebe, Donald

    2010-01-01

    We present results from a survey carried out by the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) on a 9 deg^2 field near the South Ecliptic Pole at 250, 350 and 500 {\\mu}m. The median 1{\\sigma} depths of the maps are 36.0, 26.4 and 18.4 mJy, respectively. We apply a statistical method to estimate submillimeter galaxy number counts and find that they are in agreement with other measurements made with the same instrument and with the more recent results from Herschel/SPIRE. Thanks to the large field observed, the new measurements give additional constraints on the bright end of the counts. We identify 132, 89 and 61 sources with S/N>4 at 250, 350, 500 {\\mu}m, respectively and provide a multi-wavelength combined catalog of 232 sources. The new BLAST maps and catalogs are available publicly at http://blastexperiment.info.

  20. Characteristics of immersion freezing nuclei at the south pole station in Antarctica

    Directory of Open Access Journals (Sweden)

    K. Ardon-Dryer

    2011-01-01

    Full Text Available The effectiveness of aerosols as immersion freezing nuclei at the South Pole station was investigated during January and February 2009 using the FRIDGE-TAU. The analysis consisted of testing the freezing temperature of about 100–130 drops per sample containing aerosols collected at ground level and on a balloon lifted to different heights. All the drops froze between −18 °C and −27 °C. The temperature in which 50% of the drops froze occurred at −24 °C, while nuclei concentration of 1 L−1 at −22 °C was calculated. Meteorological conditions such as wind speed, ice precipitation as well as the trajectories of the air masses affected the ice nuclei concentrations. Higher concentrations were observed on days when the winds were stronger or when the air mass originated from the sea.

  1. Acoustic noise in deep ice and environmental conditions at the South Pole

    CERN Document Server

    Karg, Timo

    2008-01-01

    To study the acoustic properties of the Antarctic ice the South Pole Acoustic Test Setup (SPATS) was installed in the upper part of drill holes for the IceCube neutrino observatory. An important parameter for the design of a future acoustic neutrino telescope is the acoustic background noise in the ice and its spatial and temporal variations. We study the absolute noise level depth profile from SPATS data and discuss systematic uncertainties. The measured noise is very stable over one year of data taking, and we estimate the absolute noise level to be < 10 mPa in the frequency range from 10 kHz to 50 kHz at depths below 200 m. This noise level is of the same order of magnitude as observed by ocean based acoustic neutrino detection projects in good weather conditions.

  2. Modern Questions of Celestial Mechanics

    CERN Document Server

    Colombo, Giovanni

    2011-01-01

    C. Agostinelli: Sul problema delle aurore boreali e il moto di un corpuscolo elettrizzato in presenza di un dipolo magnetico.- G. Colombo: Introduction to the theory of earth's motion about its center of mass.- E.M. Gaposchkin: The motion of the pole and the earth's elasticity as studied from the gravity field of the earth by means of artificial earth satellites.- I.I. Shapiro: Radar astronomy, general relativity, and celestial mechanics.- V. Szebehely: Applications of the restricted problem of three bodies in space research.- G.A. Wilkins: The analysis of the observation of the satellites of

  3. Plans for a 10-m submillimeter-wave telescope at the South Pole

    Science.gov (United States)

    Stark, Antony A.; Carlstrom, John E.; Israel, Frank P.; Menten, Karl M.; Peterson, Jeffrey B.; Phillips, Thomas G.; Sironi, Giorgio; Walker, Christopher K.

    1998-07-01

    A 10 meter diameter submillimeter-wave telescope has been proposed for installation and scientific use at the NSF Amundsen-Scott South Pole Station. Current evidence indicates that the South Pole is the best submillimeter-wave telescope site among all existing or proposed ground-based observatories. Proposed scientific programs place stringent requirements on the optical quality of the telescope design. In particular, reduction of the thermal background and offsets requires an off-axis, unblocked aperture, and the large field of view needed for survey observations requires shaped optics. This mix of design elements is well-suited for large-scale (square degree) mapping of line and continuum radiation from submillimeter-wave sources at moderate spatial resolutions (4 to 60 arcsecond beam size) and high sensitivity (milliJansky flux density levels). The telescope will make arcminute angular scale, high frequency Cosmic Microwave Background measurements from the best possible ground-based site, using an aperture which is larger than is currently possible on orbital or airborne platforms. The telescope design is homologous. Gravitational changes in pointing and focal length will be accommodated by active repositioning of the secondary mirror. The secondary support, consisting of a large, enclosed beam, permits mounting of either a standard set of Gregorian optics, or prime focus instrumentation packages for CMBR studies. A tertiary chopper is located at the exit pupil of the instrument. An optical design with a hyperboloidal primary mirror and a concave secondary mirror provides a flat focal surface. The relatively large classical aberrations present in such an optical arrangement can be small compared to diffraction at submillimeter wavelengths. Effective use of this telescope will require development of large (1000 element) arrays of submillimeter detectors which are background-limited when illuminated by antenna temperatures near 50 K.

  4. Feasibility of acoustic neutrino detection in ice: Design and performance of the South Pole Acoustic Test Setup (SPATS)

    CERN Document Server

    Boeser, S; Descamps, F; Fischer, J; Hallgren, A; Heller, R; Hundertmark, S; Krieger, K; Nahnhauer, R; Pohl, M; Price, P B; Sulanke, K -H; Tosi, D; Vandenbroucke, J

    2008-01-01

    The South Pole Acoustic Test Setup (SPATS) has been built to evaluate the acoustic characteristics of the South Pole ice in the 10 to 100 kHz frequency range so that the feasibility and specific design of an acoustic neutrino detection array at South Pole can be evaluated. SPATS consists of three vertical strings that were deployed in the upper 400 meters of the South Pole ice cap in January 2007, using the upper part of IceCube holes. The strings form a triangular array with the longest baseline 421 meters. Each of them has 7 stages with one transmitter and one sensor module. Both are equipped with piezoelectric ceramic elements in order to produce or detect sound. Analog signals are brought to the surface on electric cables where they are digitized by a PC-based data acquisition system. The data from all three strings are collected on a master-PC in a central facility, from which they are sent to the northern hemisphere via a satellite link or locally stored on tape. A technical overview of the SPATS detect...

  5. Foucault pendulum at the south pole: Proposal for an experiment to detect the earth's general relativistic gravitomagnetic field

    International Nuclear Information System (INIS)

    An experiment is proposed for measuring the earth's gravitomagnetic field by monitoring its effect on the plane of swing of a Foucault pendulum at the south pole (''dragging of inertial frames by earth's rotation''). With great effort a 10% experiment in a measurement time of several months might be achieved

  6. Space-time structure of auroral radio absorption events observed with the imaging riometer at South Pole

    International Nuclear Information System (INIS)

    An imaging riometer system comprising 49 independent beams has been operating at South Pole station since January 1988. A study of intense, short-duration events from the premidnight sector has defined their typical shape as elliptical, with axial ratio 2.3 oriented along the local L shell. The space-time evolution shows rapid intensifications of the moving absorption patches. 15 refs

  7. The controlled ecological life support system Antarctic analog project: Analysis of wastewater from the South Pole Station, Antarctica, volume 1

    Science.gov (United States)

    Flynn, Michael T.; Bubenheim, David L.; Straight, Christian L.; Belisle, Warren

    1994-01-01

    The Controlled Ecological Life Support system (CELSS) Antarctic Analog Project (CAAP) is a joint National Science Foundation (NSF) and NASA project for the development, deployment and operation of CELSS technologies at the Amundsen-Scott South Pole Station. NASA goals are operational testing of CELSS technologies and the conduct of scientific studies to facilitate technology selection and system design. The NSF goals are that the food production, water purification, and waste treatment capabilities which will be provided by CAAP will improve the quality of life for the South Pole inhabitants, reduce logistics dependence, and minimize environmental impacts associated with human presence on the polar plateau. This report presents an analysis of wastewater samples taken from the Amundsen-Scott South Pole Station, Antarctica. The purpose of the work is to develop a quantitative understanding of the characteristics of domestic sewage streams at the South Pole Station. This information will contribute to the design of a proposed plant growth/waste treatment system which is part of the CELSS Antarctic Analog Project (CAAP).

  8. Albedo of the South Pole on Mars Determined by Topographic Forcing of Atmosphere Dynamics

    Science.gov (United States)

    Colaprete, Anthony; Barnes, Jeffrey R.; Haberle, Robert M.; Hollingsworth, Jeffery L.; Kleffer, Hugh H.; Titus, Timothy N.

    2005-01-01

    The nature of the martian south polar cap has remained enigmatic since the first spacecraft observations. In particular, the presence of a perennial carbon dioxide ice cap, the formation of a vast area of black slab ice known as the Cryptic region and the asymmetric springtime retreat of the cap have eluded explanation. Here we present observations and climate modelling that indicate the south pole of Mars is characterized by two distinct regional climates that are the result of dynamical forcing by the largest southern impact basins, Argyre and Hellas. The style of surface frost deposition is controlled by these regional climates. In the cold and stormy conditions that exist poleward of 60 degrees S and extend 180 degrees in longitude west from the Mountains of Mitchel (about 30 degrees W), surface frost accumulation is dominated by precipitation. In the opposite hemisphere, the polar atmosphere is relatively warm and clear and frost accumulation is dominated by direct vapour deposition. It is the differences in these deposition styles that determine the cap albedo.

  9. The Meteorology and Chemistry of High Nitric-Acid Episodes at the South Pole

    Science.gov (United States)

    Neff, William; Davis, Douglas

    2016-04-01

    Between 1998 and 2007, a series of field experiments carried out at the South Pole and with aircraft over a wider area revealed a very chemically active boundary layer overlying the east Antarctic ice sheet during the Austral summer. An early discovery was unexpectedly high concentrations of nitric acid (NO) at the South Pole. These were argued to be a result of the UV pholoysis of reactive nitrogen in surface and/or near-surface snow followed by subsequent confinement and non-linear HOx/NOx chemistry within a thin stable atmospheric boundary layer. The concentrations of NO also demonstrated daily, intraseasonal, as well as interannual variability as seen in the four field programs. This paper seeks to elucidate the interplay of large-to-small scale meteorology and chemistry at the South Pole that leads to highly variable NO concentrations and to examine boundary layer depth effects on NO in years when no direct measurements were available, in particular during the latest field program in 2006-2007. The importance of the South Pole is that it, unlike other high-latitude sites, has no diurnal cycle to disturb the evolution of the mostly stable boundary layer and its physics and chemistry. In the spring, as the solar elevation angle increases, nitrate photolysis rates increase. At the same time, the stratospheric vortex warms and with its breakup, the total column ozone increases leading to decreased photolysis rates. In addition, following the formation of the thermal tropopause in early spring, the tropospheric circulation over Antarctica changes dramatically, affecting the transport and dominant source regions for warm air and clouds arriving at the South Pole. The timing of the final warming ranged from early-November to mid-December for the four field experiment years. During the 30 days prior to the final increase in column ozone, as the thermal tropopause forms (~100 hPa), the winds at 300 hPa become bimodal, either along the eastern side of the Weddell Sea

  10. Boundary Layer and Synoptic Effects on NO Concentrations at the South Pole: A Multiyear Perspective

    Science.gov (United States)

    Neff, William; Davis, Douglas

    2015-04-01

    A series of experiments have explored the behavior of NO concentrations at the South Pole as part of the ISCAT (1998, 2000) and ANTCI (2003, 2005, 2006-7) field programs [Davis et al., 2008]. The relationship between NO and boundary layer depth (BLD) proposed by [Davis et al., 2004] was verified by [Neff et al., 2008] using direct sodar measurements of BLD during the period November-December 2003. A longer time series of NOx was generated in the ANTCI program from sunrise in 2006 into summer 2007. However, no direct BLD measurements were available. To address this deficiency, we used multiple linear regression on data from 2003 where both directly observed BLD and meteorological variables were recorded. This analysis showed that the three most important variables were wind speed (r2=0.56), Delta T2-22m (r2=0.32), and wind direction (r2=0.10). The strong dependence on wind speed is consistent with the results of [Neff et al., 2008] showing the dependence of BLD on surface stress (representing turbulent mixing of momentum to the surface). The dependence on wind direction may be unique to the South Pole because of the constancy of surface winds from the northeast that are weakly perturbed by synoptic weather systems: winds from grid east tend to be light, colder, and with shallower BLD whereas those from grid north are stronger, warmer, and have greater BLD. To further test these regression results, we used lower resolution sodar data from the austral spring of 1993(e.g., October/ November). From these data we found that applying the 2003 regression analysis results to 1993 data, ~32% of the variance could be accounted for, despite the coarseness of the 1993 observations. The latter result provided the justification for applying the 2003 BLD regression analysis to our estimating BLDs on the 2006-7 NOx data set. As found in the 2003 data set, the general trend in the 2006-7 data showed that predicted shallow BLDs consistently correlated with higher concentrations of

  11. Solar irradiance at the earth's surface: long-term behavior observed at the South Pole

    Directory of Open Access Journals (Sweden)

    J. E. Frederick

    2011-02-01

    Full Text Available This research examines a 17-year database of UV-A (320–400 nm and visible (400–600 nm solar irradiance obtained by a scanning spectroradiometer located at the South Pole. The goal is to define the variability in solar irradiance reaching the polar surface, with emphasis on the influence of cloudiness and on identifying systematic trends and possible links to the solar cycle. To eliminate changes associated with the varying solar elevation, the analysis focuses on data averaged over 30–35 day periods centered on each year's austral summer solstice. The long-term average effect of South Polar clouds is a small attenuation, with the mean measured irradiances being about 5–6% less than the clear-sky values, although at any specific time clouds may reduce or enhance the signal that reaches the sensor. The instantaneous fractional attenuation or enhancement is wavelength dependent, where the percent deviation from the clear-sky irradiance at 400–600 nm is typically 2.5 times that at 320–340 nm. When averaged over the period near each year's summer solstice, significant correlations appear between irradiances at all wavelengths and the solar cycle as measured by the 10.7 cm solar radio flux. An approximate 1.8 ± 1.0% decrease in ground-level irradiance occurs from solar maximum to solar minimum for the wavelength band 320–400 nm. The corresponding decrease for 400–600 nm is 2.4 ± 1.9%. The best-estimate declines appear too large to originate in the sun. If the correlations have a geophysical origin, they suggest a small variation in atmospheric attenuation with the solar cycle over the period of observation, with the greatest attenuation occurring at solar minimum.

  12. GCM simulations of atmospheric tracers in the polar latitudes: South Pole (Antarctica) and Summit (Greenland) cases

    International Nuclear Information System (INIS)

    Simulation results from two global atmospheric tracer/climate models in the interior of the two major ice sheets at high northern and southern latitudes are presented and discussed. The models are based on two existing general circulation models (GCMs) of the atmosphere, complemented with tracer formulations (sources, transport, mixing, deposition, etc.). The seasonal and shorter term variability of desert dust, sea salt, 222Rn, 210Pb, and 7Be has been studied at the South Pole in Antarctica and at Summit in Greenland. This choice of tracers and test regions serves to focus on the interactions between atmospheric parameters (e.g. the strong and durable surface inversions characteristic of the ice sheets) and tracers, and to limit other influences such as source variability and chemistry. Comparison with available observations is not consistently favorable. Short-term variability in the atmosphere (222Rn and 210Pb) appears qualitatively reasonable. Seasonal cycles are in some instances opposite to those observed, and mean deposition is clearly too high. The coarseness of model resolution at the high latitudes and the difficulty of setting up efficient formulations for microphysical tracer processes (e.g. dry and wet deposition) are major sources of problems. If these obstacles are overcome, the combined tracer/climate modelling approach can offer quantitative interpretation of the observed features of atmospheric contaminants, or sensitive tests of GCM simulated atmospheric circulation

  13. Analysis of Stationary, Photovoltaic-based Surface Power System Designs at the Lunar South Pole

    Science.gov (United States)

    Freeh, Joshua E.

    2009-01-01

    Combinations of solar arrays and either batteries or regenerative fuel cells are analyzed for a surface power system module at the lunar south pole. The systems are required to produce 5 kW of net electrical power in sunlight and 2 kW of net electrical power during lunar night periods for a 10-year period between 2020 and 2030. Systems-level models for energy conservation, performance, degradation, and mass are used to compare to various systems. The sensitivities of important and/or uncertain variables including battery specific energy, fuel cell operating voltage, and DC-DC converter efficiency are compared to better understand the system. Switching unit efficiency, battery specific energy, and fuel cell operating voltage appear to be important system-level variables for this system. With reasonably sized solar arrays, the regenerative fuel cell system has significantly lower mass than the battery system based on the requirements and assumptions made herein. The total operational time is estimated at about 10,000 hours in battery discharge/fuel cell mode and about 4,000 and 8,000 hours for the battery charge and electrolyzer modes, respectively. The estimated number of significant depth-of-discharge cycles for either energy storage system is less than 100 for the 10-year period.

  14. Spitzer MIPS 24 and 70 micron Imaging near the South Ecliptic Pole: Maps and Source Catalogs

    CERN Document Server

    Scott, Kimberly S; Braglia, Filiberto G; Borys, Colin; Chapin, Edward L; Devlin, Mark J; Marsden, Gaelen; Scott, Douglas; Truch, Matthew D P; Valiante, Elisabetta; Viero, Marco P

    2010-01-01

    We have imaged an 11.5 sq. deg. region of sky towards the South Ecliptic Pole (RA = 04h43m, Dec = -53d40m, J2000) at 24 and 70 microns with MIPS, the Multiband Imaging Photometer for Spitzer. This region is coincident with a field mapped at longer wavelengths by the Balloon-borne Large Aperture Submillimeter Telescope. We discuss our data reduction and source extraction procedures. The median depths of the maps are 47 microJy/beam at 24 micron and 4.3 mJy/beam at 70 micron. At 24 micron, we identify 93098 point sources with signal-to-noise ratio (SNR) >5, and an additional 63 resolved galaxies; at 70 micron, we identify 891 point sources with SNR >6. From simulations, we determine a false detection rate of 1.8% (1.1%) for the 24 micron (70 micron) catalog. The 24 and 70 micron point-source catalogs are 80% complete at 230 microJy and 11 mJy, respectively. These mosaic images and source catalogs will be available to the public through the NASA/IPAC Infrared Science Archive.

  15. The Spitzer-IRAC/MIPS Extragalactic survey (SIMES) in the South Ecliptic Pole field

    CERN Document Server

    Baronchelli, I; Rodighiero, G; Franceschini, A; Capak, P L; Mei, S; Vaccari, M; Marchetti, L; Hibon, P; Sedgwick, C; Pearson, C; Serjeant, S; Menèndez-Delmestre, K; Salvato, M; Malkan, M; Teplitz, H I; Hayes, M; Colbert, J; Papovich, C; Devlin, M; Kovacs, A; Scott, K S; Surace, J; Kirkpatrick, J D; Atek, H; Urrutia, T; Scoville, N Z; Takeuchi, T T

    2016-01-01

    We present the Spitzer-IRAC/MIPS Extragalactic survey (SIMES) in the South Ecliptic Pole (SEP) field. The large area covered (7.7 deg$^2$), together with one of the lowest Galactic cirrus emissions in the entire sky and a very extensive coverage by Spitzer, Herschel, Akari, and GALEX, make the SIMES field ideal for extragalactic studies. The elongated geometry of the SIMES area ($\\approx$4:1), allowing for a significant cosmic variance reduction, further improves the quality of statistical studies in this field. Here we present the reduction and photometric measurements of the Spitzer/IRAC data. The survey reaches a depth of 1.93 and 1.75 $\\mu$Jy (1$\\sigma$) at 3.6 and 4.5 $\\mu$m, respectively. We discuss the multiwavelength IRAC--based catalog, completed with optical, mid-- and far--IR observations. We detect 341,000 sources with F$_{3.6\\mu m} \\geq 3\\sigma$. Of these, 10% have an associated 24 $\\mu$m counterpart, while 2.7% have an associated SPIRE source. We release the catalog through the NASA/IPAC Infrare...

  16. Volume of Impact Melt Generated by the Formation of the South Pole-Aitken Basin

    Science.gov (United States)

    Petro, Noah E.

    2011-01-01

    The South Pole-Aitken Basin (SPA) is the largest, deepest, and oldest identified basin on the Moon and as such contains surfaces that are unique due to their age, composition, and depth of origin in the lunar crust [1-5] (Figure 1). SPA has been a target of intense interest as an area for robotic sample return in order to determine the age of the basin and the composition and origin of its interior [6-8]. In response to this interest there have been several efforts to estimate the likely provenance of regolith material within central SPA [9-12]. These model estimates suggest that, despite the formation of basins and craters following SPA, the regolith within SPA is dominated by locally derived material. An assumption of these models has been that the locally derived material is primarily SPA impact-melt as opposed to local basement material (e.g. unmelted lower crust). However, the definitive identification of SPA derived impact melt on the basin floor, either by remote sensing [5, 13] or via photogeology [2, 14] is extremely difficult due to the number of subsequent impacts and volcanic activity [4].

  17. Geomorphic Terrains and Evidence for Ancient Volcanism within Northeastern South Pole-Aitken Basin

    Science.gov (United States)

    Petro, Noah; Mest, Scott C.; Teich, Yaron

    2010-01-01

    The interior of the enigmatic South Pole-Aitken Basin has long been recognized as being compositionally distinct from its exterior. However, the source of the compositional anomaly has been subject to some debate. Is the source of the iron-enhancement due to lower-crustal/upper-mantle material being exposed at the surface, or was there some volume of ancient volcanism that covered portions of the basin interior? While several obvious mare basalt units are found within the basin and regions that appear to represent the original basin interior, there are several regions that appear to have an uncertain origin. Using a combination of Clementine and Lunar Orbiter images, several morphologic units are defined based on albedo, crater density, and surface roughness. An extensive unit of ancient mare basalt (cryptomare) is defined and, based on the number of superimposed craters, potentially represents the oldest volcanic materials within the basin. Thus, the overall iron-rich interior of the basin is not solely due to deeply derived crustal material, but is, in part due to the presence of ancient volcanic units.

  18. Prospects for a radio air-shower detector at South Pole

    CERN Document Server

    ,

    2012-01-01

    IceCube is currently not only the largest neutrino telescope but also one of the world's most competitive instruments for studying cosmic rays in the PeV to EeV regime where the transition from galactic to extra-galactic sources should occur. Further augmenting this observatory with an array of radio sensors in the 10-100 MHz regime will additionally permit observation of the geomagnetic radio emission from the air shower. Yielding complementary information on the shower development a triple-technology array consisting of radio sensors, the ground sampling stations of IceTop and the in-ice optical modules of IceCube, should significantly improve the understanding of cosmic rays, as well as enhance many aspects of the physics reach of the observatory. Here we present first results from two exploratory setups deployed at the South Pole. Noise measurements from data taken in two consecutive seasons show a very good agreement of the predicted and observed response of the antennas designed specifically for this pu...

  19. Optical Characterization of the BICEP3 CMB Polarimeter at the South Pole

    CERN Document Server

    Karkare, K S; Ahmed, Z; Alexander, K D; Amiri, M; Barkats, D; Benton, S J; Bischoff, C A; Bock, J J; Boenish, H; Bowens-Rubin, R; Buder, I; Bullock, E; Buza, V; Connors, J; Filippini, J P; Fliescher, S T; Grayson, J A; Halpern, M; Harrison, S A; Hilton, G C; Hristov, V V; Hui, H; Irwin, K D; Kang, J H; Karpel, E; Kefeli, S; Kernasovskiy, S A; Kovac, J M; Kuo, C L; Leitch, E M; Lueker, M; Megerian, K G; Monticue, V; Namikawa, T; Netterfield, C B; Nguyen, H T; O'Brient, R; Ogburn, R W; Pryke, C; Reintsema, C D; Richter, S; Germaine, M T St; Schwarz, R; Sheehy, C D; Staniszewski, Z K; Steinbach, B; Teply, G P; Thompson, K L; Tolan, J E; Tucker, C; Turner, A D; Vieregg, A G; Wandui, A; Weber, A; Willmert, J; Wong, C L; Wu, W L K; Yoon, K W

    2016-01-01

    BICEP3 is a small-aperture refracting cosmic microwave background (CMB) telescope designed to make sensitive polarization maps in pursuit of a potential B-mode signal from inflationary gravitational waves. It is the latest in the BICEP/Keck Array series of CMB experiments at the South Pole, which has provided the most stringent constraints on inflation to date. For the 2016 observing season, BICEP3 was outfitted with a full suite of 2400 optically coupled detectors operating at 95 GHz. In these proceedings we report on the far field beam performance using calibration data taken during the 2015-2016 summer deployment season in situ with a thermal chopped source. We generate high-fidelity per-detector beam maps, show the array-averaged beam profile, and characterize the differential beam response between co-located, orthogonally polarized detectors which contributes to the leading instrumental systematic in pair differencing experiments. We find that the levels of differential pointing, beamwidth, and elliptici...

  20. Maps of the Magellanic Clouds from Combined South Pole Telescope and Planck Data

    CERN Document Server

    Crawford, T M; Holder, G P; Aird, K A; Benson, B A; Bleem, L E; Carlstrom, J E; Chang, C L; Cho, H-M; Crites, A T; de Haan, T; Dobbs, M A; George, E M; Halverson, N W; Harrington, N L; Holzapfel, W L; Hou, Z; Hrubes, J D; Keisler, R; Knox, L; Lee, A T; Leitch, E M; Luong-Van, D; Marrone, D P; McMahon, J J; Meyer, S S; Mocanu, L M; Mohr, J J; Natoli, T; Padin, S; Pryke, C; Reichardt, C L; Ruhl, J E; Sayre, J T; Schaffer, K K; Shirokoff, E; Staniszewski, Z; Stark, A A; Story, K T; Vanderlinde, K; Vieira, J D; Williamson, R

    2016-01-01

    We present maps of the Large and Small Magellanic Clouds from combined South Pole Telescope (SPT) and Planck data. Both instruments are designed to make measurements of the cosmic microwave background but are sensitive to any source of millimeter-wave (mm-wave) emission. The Planck satellite observes in nine mm-wave bands, while the SPT data used in this work were taken with the three-band SPT-SZ camera. The SPT-SZ bands correspond closely to three of the nine Planck bands, namely those centered at 1.4, 2.1, and 3.0 mm. The angular resolution of the Planck data in these bands ranges from 5 to 10 arcmin, while the SPT resolution in these bands ranges from 1.0 to 1.7 arcmin. The combined maps take advantage of the high resolution of the SPT data and the long-timescale stability of the space-based Planck observations to deliver high signal-to-noise and robust brightness measurements on scales from the size of the maps down to ~1 arcmin. In each of the three bands, we first calibrate and color-correct the SPT dat...

  1. Multichroic TES Bolometers and Galaxy Cluster Mass Scaling Relations with the South Pole Telescope

    CERN Document Server

    Saliwanchik, Benjamin

    2016-01-01

    The South Pole Telescope (SPT) is a high-resolution microwave-frequency telescope designed to observe the Cosmic Microwave Background (CMB). To date, two cameras have been installed on the SPT to conduct two surveys of the CMB, the first in intensity only (SPT-SZ) and the second in intensity and polarization (SPTpol). A third-generation polarization-sensitive camera is currently in development (SPT-3G). This thesis describes work spanning all three instruments on the SPT. I present my work in time-reversed order, to follow the canonical narrative of instrument development, deployment, and analysis. First, the development and testing of novel 3-band multichroic Transition Edge Sensor (TES) bolometers for the SPT-3G experiment is detailed, followed by the development and deployment of the frequency multiplexed cryogenic readout electronics for the SPTpol experiment, and concluding with the analysis of data taken by the SPT-SZ instrument. I describe the development of a Bayesian likelihood based method I develop...

  2. Improved constraints on cosmic microwave background secondary anisotropies from the complete 2008 South Pole Telescope data

    CERN Document Server

    Shirokoff, E; Shaw, L; Millea, M; Ade, P A R; Aird, K A; Benson, B A; Bleem, L E; Carlstrom, J E; Chang, C L; Cho, H M; Crawford, T M; Crites, A T; de Haan, T; Dobbs, M A; Dudley, J; George, E M; Halverson, N W; Holder, G P; HOlzapfel, W L; Hrubes, J D; Joy, M; Keisler, R; Knox, L; Lee, A T; Leitch, E M; Lueker, M; Luong-Van, D; McMahon, J J; Mehl, J; Meyer, S S; Mohr, J J; Montroy, T E; Padin, S; Plagge, T; Pryke, C; Ruhl, J E; Schaffer, K K; Spieler, H G; Staniszewski, Z; Stark, A A; Story, K; Vanderlinde, K; Vieira, J D; Williamson, R; Zahn, O

    2010-01-01

    We report measurements of the cosmic microwave background (CMB) power spectrum from the complete 2008 South Pole Telescope (SPT) data set. We analyze twice as much data as the first SPT power spectrum analysis, using an improved cosmological parameter estimator which fits multi-frequency models to the SPT $150$ and $220\\,$GHz bandpowers. We find an excellent fit to the measured bandpowers with a model that includes lensed primary CMB anisotropy, secondary thermal (tSZ) and kinetic (kSZ) Sunyaev-Zel'dovich anisotropies, unclustered synchrotron point sources, and clustered dusty point sources. In addition to measuring the power spectrum of dusty galaxies at high signal-to-noise, the data primarily constrain a linear combination of the kSZ and tSZ anisotropy contributions at $150\\,$GHz and $\\ell=3000$: $D^{tSZ}_{3000} + 0.5\\,D^{kSZ}_{3000} = 4.5\\pm 1.0 \\,\\mu{\\rm K}^2$. The $95%$ confidence upper limits on secondary anisotropy power are $D^{tSZ}_{3000} < 5.3\\,\\mu{\\rm K}^2$ and $D^{kSZ}_{3000} < 6.5\\,\\mu{\\rm...

  3. Photometry of the 4686 A emission line of gamma(2) Velorum from the South Pole

    International Nuclear Information System (INIS)

    An automated optical telescope located at the Amundsen-Scott South Pole station on Antarctica, has been used to obtain more than 78 h of photometry of the He II emission line (4686 A) of the spectroscopic binary gamma(2) Velorum. These data were obtained on seven different days during the 1987 austral winter; the longest continuous run spans 19 h. Two independent period search techniques have been used to search for periodic behavior in the strength of the He II emission line of this Wolf-Rayet star. They are: (1) power spectrum analysis and (2) a first-order sine function fit to the data using least squares. Various multiplicities of a period on the order of 1.3 h with amplitudes of a few percent are found in most of these data. According to recent theoretical models of Wolf-Rayet stars, fluctuations in the He II emission line may indicate vibrational instability in gamma(2) Vel. These pulsations may, in turn, give rise to shocks which propagate outward and which may provide the necessary conditions for periodic changes in the state of a given region of the atmosphere to occur. 15 refs

  4. High-resolution Local Gravity Model of the South Pole of the Moon from GRAIL Extended Mission Data

    Science.gov (United States)

    Goossens, Sander Johannes; Sabaka, Terence J.; Nicholas, Joseph B.; Lemoine, Frank G.; Rowlands, David D.; Mazarico, Erwan; Neumann, Gregory A.; Smith, David E.; Zuber, Maria T.

    2014-01-01

    We estimated a high-resolution local gravity field model over the south pole of the Moon using data from the Gravity Recovery and Interior Laboratory's extended mission. Our solution consists of adjustments with respect to a global model expressed in spherical harmonics. The adjustments are expressed as gridded gravity anomalies with a resolution of 1/6deg by 1/6deg (equivalent to that of a degree and order 1080 model in spherical harmonics), covering a cap over the south pole with a radius of 40deg. The gravity anomalies have been estimated from a short-arc analysis using only Ka-band range-rate (KBRR) data over the area of interest. We apply a neighbor-smoothing constraint to our solution. Our local model removes striping present in the global model; it reduces the misfit to the KBRR data and improves correlations with topography to higher degrees than current global models.

  5. Ground-based instrumentation for measurements of atmospheric conduction current and electric field at the South Pole

    Science.gov (United States)

    Byrne, G. J.; Benbrook, J. R.; Bering, E. A.; Few, A. A.; Morris, G. A.; Trabucco, W. J.; Paschal, E. W.

    1993-01-01

    Attention is given to instruments constructed to measure the atmospheric conduction current and the atmospheric electric field - two fundamental parameters of the global-electric circuit. The instruments were deployed at the Amundsen-Scott South Pole Station in January 1991 and are designed to operate continuously for up to one year without operator intervention. The atmospheric current flows into one hemisphere, through the electronics where it is measured, and out the other hemisphere. The electric field is measured by a field mill of the rotating dipole type. Sample data from the first days of operation at the South Pole indicate variations in the global circuit over time scales from minutes to hours to days.

  6. The South Pole-Aitken basin region, Moon: GIS-based geologic investigation using Kaguya elemental information

    OpenAIRE

    King, Kyeong Ja; Dohm, James M.; Williams, Jean-Pierre; Ruiz Pérez, Javier; Hare, Trent M.; Hasebe, Nobuyuki; Karouji, Yuzuru; Kobayashi, Shingo; Hareyama, Makoto; Shibamura, Eido; KOBAYASHI, Masanori; Uston, Claude d'; Gasnault, Olivier; Forni, Olivier; Maurice, Sylvestre

    2012-01-01

    Using Geographic Information Systems (GIS), we performed comparative analysis among stratigraphic information and the Kaguya (SELENE) GRS data of the 2500-km-diameter South Pole-Aitken (SPA) basin and its surroundings. Results indicate chat the surface rock materials (including ancient crater materials, mare basalts, and possible SPA impact melt) are average to slightly elevated in K and Th with respect to the rest of the Moon. Also, this study demonstrates that K and Th have not significa...

  7. Geologic Mapping of the Lunar South Pole, Quadrangle LQ-30: Volcanic History and Stratigraphy of Schroedinger Basin

    Science.gov (United States)

    Mest, S. C.; Berman, D. C.; Petro, N. E.

    2009-01-01

    In this study we use recent images and topographic data to map the geology and geomorphology of the lunar South Pole quadrangle (LQ-30) at 1:2.5M scale [1-4] in accordance with the Lunar Geologic Mapping Program. Mapping of LQ-30 began during Mest's postdoctoral appointment and has continued under the PG&G Program, from which funding became available in February 2009. Preliminary map-ping and analyses have been done using base materials compiled by Mest, but properly mosaicked and spatially registered base materials are being compiled by the USGS and should be received by the end of June 2009. The overall objective of this research is to constrain the geologic evolution of the lunar South Pole (LQ-30: 60deg -90deg S, 0deg - +/-180deg ) with specific emphasis on evaluation of a) the regional effects of basin formation on the structure and composition of the crust and b) the spatial distribution of ejecta, in particular resulting from formation of the South Pole-Aitken (SPA) basin and other large basins. Key scientific objectives include: 1) Constraining the geologic history of the lunar South Pole and examining the spatial and temporal variability of geologic processes within the map area. 2) Constraining the vertical and lateral structure of the lunar regolith and crust, assessing the distribution of impact-generated materials, and determining the timing and effects of major basin-forming impacts on crustal structure and stratigraphy in the map area. And 3) assessing the distribution of resources (e.g., H, Fe, Th) and their relationships with surface materials.

  8. NEXT-Lunar Lander -an Opportunity for a Close Look at the Lunar South Pole

    Science.gov (United States)

    Homeister, Maren; Thaeter, Joachim; Scheper, Marc; Apeldoorn, Jeffrey; Koebel, David

    The NEXT-Lunar Lander mission, as contracted by ESA and investigated by OHB-System and its industrial study team, has two main purposes. The first is technology demonstration for enabling technologies like propulsion-based soft precision landing for future planetary landing missions. This involves also enabling technology experiments, like fuel cell, life science and life support, which are embedded in the stationary payload of the lander. The second main and equally important aspect is the in-situ investigation of the surface of the Moon at the lunar South Pole by stationary payload inside the Lander, deployable payload to be placed in the vicinity of the lander and mobile payload carried by a rover. The currently assessed model payload includes 15 instruments on the lander and additional five on the rover. They are addressing the fields geophysics, geochemistry, geology and radio astronomy preparation. The mission is currently under investigation in frame of a phase A mission study contract awarded by ESA to two independent industrial teams, of which one is led by OHB-System. The phase A activities started in spring 2008 and were conducted until spring 2010. A phase B is expected shortly afterwards. The analysed mission architectures range from a Soyuz-based mission to a Shared-Ariane V class mission via different transfer trajectories. Depending on the scenario payload masses including servicing of 70 to 150 kg can be delivered to the lunar surface. The lander can offer different services to the payload. The stationary payload is powered and conditioned by the lander. Examples for embarked payloads are an optical camera system, a Radio Science Experiment and a radiation monitor. The lander surface payload is deployed to the lunar surface by a 5 DoF robotic arm and will be powered by the Lander. To this group of payloads belong seismometers, a magnetometer and an instrumented Mole. The mobile payload will be carried by a rover. The rover is equipped with its own

  9. MEASUREMENT OF GALAXY CLUSTER INTEGRATED COMPTONIZATION AND MASS SCALING RELATIONS WITH THE SOUTH POLE TELESCOPE

    Energy Technology Data Exchange (ETDEWEB)

    Saliwanchik, B. R.; Montroy, T. E. [Physics Department, Center for Education and Research in Cosmology and Astrophysics, Case Western Reserve University, Cleveland, OH 44106 (United States); Aird, K. A. [University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Bayliss, M. [Department of Physics, Harvard University, 17 Oxford Street, Cambridge, MA 02138 (United States); Benson, B. A.; Bleem, L. E.; Carlstrom, J. E.; Chang, C. L.; Crawford, T. M.; Crites, A. T. [Kavli Institute for Cosmological Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Bocquet, S.; Desai, S. [Department of Physics, Ludwig-Maximilians-Universität, Scheinerstr. 1, D-81679 München (Germany); Brodwin, M. [Department of Physics and Astronomy, University of Missouri, 5110 Rockhill Road, Kansas City, MO 64110 (United States); Cho, H. M. [NIST Quantum Devices Group, 325 Broadway, Mailcode 817.03, Boulder, CO 80305 (United States); Clocchiatti, A. [Departamento de Astronomia y Astrofisica, Pontificia Universidad Catolica (Chile); De Haan, T.; Dobbs, M. A.; Dudley, J. P. [Department of Physics, McGill University, 3600 Rue University, Montreal, QC H3A 2T8 (Canada); Foley, R. J.; Forman, W. R., E-mail: benjamin.saliwanchik@case.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); and others

    2015-02-01

    We describe a method for measuring the integrated Comptonization (Y {sub SZ}) of clusters of galaxies from measurements of the Sunyaev-Zel'dovich (SZ) effect in multiple frequency bands and use this method to characterize a sample of galaxy clusters detected in the South Pole Telescope (SPT) data. We use a Markov Chain Monte Carlo method to fit a β-model source profile and integrate Y {sub SZ} within an angular aperture on the sky. In simulated observations of an SPT-like survey that include cosmic microwave background anisotropy, point sources, and atmospheric and instrumental noise at typical SPT-SZ survey levels, we show that we can accurately recover β-model parameters for inputted clusters. We measure Y {sub SZ} for simulated semi-analytic clusters and find that Y {sub SZ} is most accurately determined in an angular aperture comparable to the SPT beam size. We demonstrate the utility of this method to measure Y {sub SZ} and to constrain mass scaling relations using X-ray mass estimates for a sample of 18 galaxy clusters from the SPT-SZ survey. Measuring Y {sub SZ} within a 0.'75 radius aperture, we find an intrinsic log-normal scatter of 21% ± 11% in Y {sub SZ} at a fixed mass. Measuring Y {sub SZ} within a 0.3 Mpc projected radius (equivalent to 0.'75 at the survey median redshift z = 0.6), we find a scatter of 26% ± 9%. Prior to this study, the SPT observable found to have the lowest scatter with mass was cluster detection significance. We demonstrate, from both simulations and SPT observed clusters that Y {sub SZ} measured within an aperture comparable to the SPT beam size is equivalent, in terms of scatter with cluster mass, to SPT cluster detection significance.

  10. Burnham's celestial handbook

    CERN Document Server

    Burnham, Robert

    1978-01-01

    Volume II of a comprehensive three-part guide to celestial objects outside our solar system ranges from Chamaeleon to Orion. Features coordinates, classifications, physical descriptions, hundreds of visual aids. 1977 edition.

  11. Mesopotamian Celestial Divination

    Science.gov (United States)

    Verderame, Lorenzo

    Celestial divination was an important aspect of scholarly activity in Mesopotamia. Several hundred cuneiform tablets attest to its practice and provide details of the different types of omens that were drawn from observations of the sky. This chapter outlines the sources of celestial divination in Mesopotamia and traces the development of the divinatory tradition from the late third millennium BC down to the end of the first millennium BC.

  12. Cassini VIMS Spectra of the Thermal Emission from Hot Spots Along Enceladus South Pole Fissures

    Science.gov (United States)

    Goguen, Jay D.; Buratti, Bonnie J.; Cassini VIMS Team

    2016-10-01

    Most of the south pole fissure region has not been directly illuminated by sunlight since the sub-solar point moved into the northern hemisphere in 2009, thereby eliminating the background of reflected sunlight at VIMS wavelengths and making the fissure thermal emission readily measureable. Since then, VIMS has measured spectra of at least 11 hot spots along the fissures. Most of these measurements were acquired in ride-along mode with CIRS as the prime instrument. During at least 2 encounters, VIMS and CIRS acquired simultaneous or near-simultaneous spectra of the same fissure location. VIMS spectra include multiple hot spots along Damascus, Baghdad, Cairo, and a likely hot spot on Alexandria.All of the VIMS spectra examined to date are consistent with this scenario of a self-regulating fissure maximum T~200 K with brighter VIMS emissions corresponding to fissures up to ~20 m wide. Emission from the warm fissure interior walls dominate the VIMS spectra with <15% contributed by conductive heating of the adjacent terrain at VIMS wavelengths.CIRS spectra report slightly cooler T's due to CIRS increased sensitivity to lower T emission at longer wavelengths and averaging over contributions from both the hottest and cooler areas. Combined analysis of the CIRS and VIMS spectra spanning 3 to 500 micron wavelengths promises to reveal the distribution of [T, area] near the fissures that cannot be spatially resolved. This [T, area] distribution holds the key to understanding how heat is transferred to the surface within a few 100 m of the fissures.The VIMS-detected emission is concentrated in localized hot spots along the fissures and does not seem to be distributed continuously along them. CIRS spectra suggest a more continuous distribution of the emission along the fissure length. Jets locations also are distributed along the fissure length and it appears that the VIMS-detected hot spots in general correlate with jet locations, but not all of the jet locations have been

  13. Maps of the Magellanic Clouds from Combined South Pole Telescope and Planck Data

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, T.M.; et al.

    2016-05-03

    We present maps of the Large and Small Magellanic Clouds from combined South Pole Telescope (SPT) and Planck data. Both instruments are designed to make measurements of the cosmic microwave background but are sensitive to any source of millimeter-wave (mm-wave) emission. The Planck satellite observes in nine mm-wave bands, while the SPT data used in this work were taken with the three-band SPT-SZ camera. The SPT-SZ bands correspond closely to three of the nine Planck bands, namely those centered at 1.4, 2.1, and 3.0 mm. The angular resolution of the Planck data in these bands ranges from 5 to 10 arcmin, while the SPT resolution in these bands ranges from 1.0 to 1.7 arcmin. The combined maps take advantage of the high resolution of the SPT data and the long-timescale stability of the space-based Planck observations to deliver high signal-to-noise and robust brightness measurements on scales from the size of the maps down to ~1 arcmin. In each of the three bands, we first calibrate and color-correct the SPT data to match the Planck data, then we use noise estimates from each instrument and knowledge of each instrument's beam, or point-spread function, to make the inverse-variance-weighted combination of the two instruments' data as a function of angular scale. We create maps assuming a range of underlying emission spectra (for the color correction) and at a range of final resolutions. We perform several consistency tests on the combined maps and estimate the expected noise in measurements of features in the maps. We compare the maps of the Large Magellanic Cloud (LMC) from this work to maps from the Herschel HERITAGE survey, finding general consistency between the datasets. The broad wavelength coverage provides evidence of different emission mechanisms at work in different environments in the LMC. [Abridged

  14. a Search for the Cosmic Dust Increment to Aerosol Particles at the Geographic South Pole.

    Science.gov (United States)

    Witkowski, Robert Edward

    1988-12-01

    An electrostatic precipitation (ESP) particle collector was constructed and deployed to sample the South Pole, Antarctica atmosphere for submicron-size cosmic dust particles. It was in operation between December, 1983 and January, 1987 at the National Oceanic and Atmospheric Administration (NOAA) Clean Air Facility (CAF). The collector is most efficient for particles in the 0.3 mu m size range. An arrangement of isolation shutters and removable sampling plates allows for sample transfer, without contamination, to a remote laboratory for individual particle characterization by Scanning Transmission Electron Microscopy (STEM) coupled with Energy Dispersive Spectrometry (EDS) for elemental analysis and Selected Area Electron Diffraction (SAED) for crystallographic identifications. Beside the readily identifiable contaminants, including sulfuric acid droplets that make up a significant background and sooty carbonaceous-type material, a variety of rod-shaped grains and spheres have been noted. In addition, an iron-containing mineral has been observed as fragile filamentary or needle-like crystalline aggregates. Some rather rare particles that display single element EDS signature peaks of Ti, Cr, Co, Mg, Si, and Pb and a possible Cr, Fe intermetallic or mineral particle also have been observed. While it would not be surprising for cosmic dust grains to be small in size and to have simple compositions, any concrete evidence of an extraterrestrial origin for any of these grains is lacking. Two other types of particles show a stronger possibility of cosmic origin. These are an Al, Fe particle collected during a Perseids Meteor Event and a unique particle that contains Mg, Al, Si, S, Ca, Fe and Ni in chondritic proportions. After completion of the particle collection program, the collector was shut down and returned to the laboratory for evaluation. An area of one of the stainless steel plates from the first chamber of the collector, the particle -charging section, was

  15. Moonrise: Sampling the South Pole-Aitken Basin to Address Problems of Solar System Significance

    Science.gov (United States)

    Zeigler, R. A.; Jolliff, B. L.; Korotev, R. L.; Shearer, C. K.

    2016-01-01

    A mission to land in the giant South Pole-Aitken (SPA) Basin on the Moon's southern farside and return a sample to Earth for analysis is a high priority for Solar System Science. Such a sample would be used to determine the age of the SPA impact; the chronology of the basin, including the ages of basins and large impacts within SPA, with implications for early Solar System dynamics and the magmatic history of the Moon; the age and composition of volcanic rocks within SPA; the origin of the thorium signature of SPA with implications for the origin of exposed materials and thermal evolution of the Moon; and possibly the magnetization that forms a strong anomaly especially evident in the northern parts of the SPA basin. It is well known from studies of the Apollo regolith that rock fragments found in the regolith form a representative collection of many different rock types delivered to the site by the impact process (Fig. 1). Such samples are well documented to contain a broad suite of materials that reflect both the local major rock formations, as well as some exotic materials from far distant sources. Within the SPA basin, modeling of the impact ejection process indicates that regolith would be dominated by SPA substrate, formed at the time of the SPA basin-forming impact and for the most part moved around by subsequent impacts. Consistent with GRAIL data, the SPA impact likely formed a vast melt body tens of km thick that took perhaps several million years to cool, but that nonetheless represents barely an instant in geologic time that should be readily apparent through integrated geochronologic studies involving multiple chronometers. It is anticipated that a statistically significant number of age determinations would yield not only the age of SPA but also the age of several prominent nearby basins and large craters within SPA. This chronology would provide a contrast to the Imbrium-dominated chronology of the nearside Apollo samples and an independent test of

  16. Celestial Reference Frames

    Science.gov (United States)

    Jacobs, Christopher S.

    2013-03-01

    Concepts and Background: This paper gives an overview of modern celestial reference frames as realized at radio frequencies using the Very Long baseline Interferometry (VLBI) technique. We discuss basic celestial reference frame concepts, desired properties, and uses. We review the networks of antennas used for this work. We briefly discuss the history of the science of astrometry touching upon the discovery of precession, proper motion, nutation, and parallax, and the field of radio astronomy. Building Celestial Frames: Next, we discuss the multi-step process of building a celestial frame: First candidate sources are identified based on point-like properties from single dish radio telescopes surveys. Second, positions are refined using connected element interferometers such as the Very Large Array, and the ATCA. Third, positions of approximately milli-arcsecond (mas) accuracy are determined using intercontinental VLBI surveys. Fourth, sub-mas positions are determined by multiyear programs using intercontinental VLBI. These sub-mas sets of positions are then verified by multiple teams in preparation for release to non-specialists in the form of an official IAU International Celestial Reference Frame (ICRF). The process described above has until recently been largely restricted to work at S/X-band (2.3/8.4 GHz). However, in the last decade sub-mas work has expanded to include celestial frames at K-band (24 GHz), Ka-band (32 GHz), and Q-band (43 GHz). While these frames currently have the disadvantage of far smaller data sets, the astrophysical quality of the sources themselves improves at these higher frequencies and thus make these frequencies attractive for realizations of celestial reference frames. Accordingly, we review progress at these higher frequency bands. Path to the Future: We discuss prospects for celestial reference frames over the next decade. We present an example of an error budget for astrometric VLBI and discuss the budget's use as a tool for

  17. Celestial Reference Frame

    Science.gov (United States)

    Jacobs, Christopher S.

    2013-09-01

    Concepts and Background: This paper gives an overview of modern celestial reference frames as realized at radio frequencies using the Very Long baseline Interferometry (VLBI) technique. We discuss basic celestial reference frame concepts, desired properties, and uses. We review the networks of antennas used for this work. We briefly discuss the history of the science of astrometry touching upon the discovery of precession, proper motion, nutation, and parallax, and the field of radio astronomy. Building Celestial Frames: Next, we discuss the multi-step process of building a celestial frame: First candidate sources are identified based on point-like properties from single dish radio telescopes surveys. Second, positions are refined using connected element interferometers such as the Very Large Array, and the ATCA. Third, positions of approximately milli-arcsecond (mas) accuracy are determined using intercontinental VLBI surveys. Fourth, sub-mas positions are determined by multiyear programs using intercontinental VLBI. These sub-mas sets of positions are then verified by multiple teams in preparation for release to non-specialists in the form of an official IAU International Celestial Reference Frame (ICRF). The process described above has until recently been largely restricted to work at S/X-band (2.3/8.4 GHz). However, in the last decade sub-mas work has expanded to include celestial frames at K-band (24 GHz), Ka-band (32 GHz), and Q-band (43 GHz). While these frames currently have the disadvantage of far smaller data sets, the astrophysical quality of the sources themselves improves at these higher frequencies and thus make these frequencies attractive for realizations of celestial reference frames. Accordingly, we review progress at these higher frequency bands. Path to the Future: We discuss prospects for celestial reference frames over the next decade. We present an example of an error budget for astrometric VLBI and discuss the budget's use as a tool for

  18. Light Plains in the South-Pole Aitken Basin: Surface Ages and Mineralogical Composition

    Science.gov (United States)

    Thiessen, F.; Hiesinger, H.; van der Bogert, C. H.; Pasckert, J. H.; Robinson, M. S.

    2012-04-01

    We studied light plains in the north-eastern South-Pole Aitken basin to investigate their origin, ages, and mineralogical composition. Light plains, also known as the Cayley Formation, occur on the near- and farside of the Moon. Due to their smooth texture, lower crater densities, and occurrence as crater fills, they were thought to be of volcanic origin [e.g., 1]. However, Apollo 16 samples of light plains deposits were in fact highly brecciated rocks [2]. Therefore, the Imbrium and Orientale impacts were thought to have formed light plains because they reshaped the surface thousands of kilometers from their impact sites. Subsequent studies revealed varying surface ages of light plains [e.g., 3] and different mineralogical compositions, which are in some cases more highland-like and in others more mare-like. Hence, an origin solely from the Imbrium and/or Orientale impacts is unlikely. Thus, the question whether light plains formed due to large impacts or regional cratering, or through endogenic processes remains open. We performed crater size-frequency measurements [e.g., 4] on Lunar Reconnaissance Orbiter Wide Angle Camera images and obtained absolute model ages between 3.43 and 3.81 Ga. We observed neither a distinctive peak of light plains ages nor clustering of similar ages in any specific regions of the studied area. Due to the fact that the derived ages vary as much as 380 Ma, an origin by a single event seems unlikely. Moreover, some ages even post-date the Imbrium and Orientale impacts, and thus an origin related to those impacts is not likely. Examination of multispectral data from Clementine [5] shows that the Ti abundances vary between 0.2 and 3 wt % and Fe abundances between 12.5 and 19 wt %. We observed a regional difference in distribution: light plains units within the Apollo basin have lower Fe and Ti values and are more highland-like, whereas light plains outside the Apollo basin show higher Fe and Ti values and are more mare-like. Furthermore, M

  19. Burnham's celestial handbook

    CERN Document Server

    Burnham, Robert

    1978-01-01

    Volume I of this comprehensive three-part guide to the thousands of celestial objects outside our solar system ranges from Andromeda through Cetus. Objects are grouped according to constellation, and their definitions feature names, coordinates, classifications, and physical descriptions. Additional notes offer fascinating historical information. Hundreds of visual aids. 1977 edition.

  20. Vestoid cosmic spherules from the South Pole Water Well and Transantarctic Mountains (Antarctica): A major and trace element study

    Science.gov (United States)

    Cordier, Carole; Folco, Luigi; Taylor, Susan

    2011-03-01

    We present major and trace element data of five glass cosmic spherules (CS) with differentiated compositions recovered in the South Pole Water Well and the Transantarctic Mountains, Antarctica. The differentiated CS were first identified using Fe/Mg and Fe/Mn ratios and we have now added high Rare Earth Element concentrations (5 vanadium) whose chemical behavior depends on oxidation state, known to be higher in the Martian than in the Vestoid environment. The compositions of the differentiated CS studied in this work share the characteristics of eucrites for all these indicators, providing further evidence that these differentiated CS are samples of a Vesta-like asteroid. However, their precursors show a considerable diversity in their mineralogy when compared to eucrites, that results in a wider range of major (Ca and Al) and trace element (Ba, Sr, Sc, and V) composition in differentiated CS.

  1. A Measurement of the Correlation of Galaxy Surveys with CMB Lensing Convergence Maps from the South Pole Telescope

    CERN Document Server

    Bleem, L E; Holder, G P; Aird, K A; Armstrong, R; Ashby, M L N; Becker, M R; Benson, B A; Biesiadzinski, T; Brodwin, M; Busha, M T; Carlstrom, J E; Chang, C L; Cho, H M; Crawford, T M; Crites, A T; de Haan, T; Desai, S; Dobbs, M A; Doré, O; Dudley, J; Geach, J E; George, E M; Gladders, M D; Gonzalez, A H; Halverson, N W; Harrington, N; High, F W; Holden, B P; Holzapfel, W L; Hoover, S; Hrubes, J D; Joy, M; Keisler, R; Knox, L; Lee, A T; Leitch, E M; Lueker, M; Luong-Van, D; Marrone, D P; Martinez-Manso, J; McMahon, J J; Mehl, J; Meyer, S S; Mohr, J J; Montroy, T E; Natoli, T; Padin, S; Plagge, T; Pryke, C; Reichardt, C L; Rest, A; Ruhl, J E; Saliwanchik, B R; Sayre, J T; Schaffer, K K; Shaw, L; Shirokoff, E; Spieler, H G; Stalder, B; Stanford, S A; Staniszewski, Z; Stark, A A; Stern, D; Story, K; Vallinotto, A; Vanderlinde, K; Vieira, J D; Wechsler, R H; Williamson, R; Zahn, O

    2012-01-01

    We compare cosmic microwave background lensing convergence maps derived from South Pole Telescope (SPT) data with galaxy survey data from the Blanco Cosmology Survey, the Wide-field Infrared Survey Explorer, and a new large Spitzer/IRAC field designed to overlap with the SPT survey. Using optical and infrared catalogs covering between 17 and 68 square degrees of sky, we detect correlation between the SPT convergence maps and each of the galaxy density maps at >4 sigma, with zero cross-correlation robustly ruled out in all cases. The amplitude and shape of the cross-power spectra are in good agreement with theoretical expectations and the measured galaxy bias is consistent with previous work. The detections reported here utilize a small fraction of the full 2500 square degree SPT survey data and serve as both a proof of principle of the technique and an illustration of the potential of this emerging cosmological probe.

  2. A test field for Gaia. Radial velocity catalogue of stars in the South Ecliptic Pole

    CERN Document Server

    Frémat, Y; Pancino, E; Soubiran, C; Jofré, P; Damerdji, Y; Heiter, U; Royer, F; Seabroke, G; Sordo, R; Blanco-Cuaresma, S; Jasniewicz, G; Martayan, C; Thévenin, F; Vallenari, A; Blomme, R; David, M; Gosset, E; Katz, D; Viala, Y; Boudreault, S; Cantat-Gaudin, T; Lobel, A; Meisenheimer, K; Nordlander, T; Raskin, G; Royer, P; Zorec, J

    2016-01-01

    Gaia is a space mission currently measuring the five astrometric parameters as well as spectrophotometry of at least 1 billion stars to G = 20.7 mag with unprecedented precision. The sixth parameter in phase space (radial velocity) is also measured thanks to medium-resolution spectroscopy being obtained for the 150 million brightest stars. During the commissioning phase, two fields, one around each ecliptic pole, have been repeatedly observed to assess and to improve the overall satellite performances as well as the associated reduction and analysis software. A ground-based photometric and spectroscopic survey was therefore initiated in 2007, and is still running in order to gather as much information as possible about the stars in these fields. This work is of particular interest to the validation of the Radial Velocity Spectrometer (RVS) outputs. The paper presents the radial velocity measurements performed for the Southern targets in the 12 - 17 R magnitude range on high- to mid-resolution spectra obtained...

  3. Notice of Intent to Prepare a Comprehensive Environmental Evaluation (CEE) for the Construction and Operation of a High-Energy Neutrino Telescope (Project Ice Cube) at the South Pole

    CERN Multimedia

    2003-01-01

    Request for comments from the NSF for a proposed project to construct and operate a high-energy neutrino telescope at the South Pole. The proposed telescope would be a second-generation instrument based on the successful evolution of a smaller neutrino telescope at the South Pole (1 page).

  4. Researcher and Educator Long Term Collaboration with NOAA ESRL Regarding Atmospheric Ozone Changes at the South Pole Through the NSF PolarTREC Program

    Science.gov (United States)

    Bergholz, E. H.; Hofmann, D. J.; Johnson, B. J.

    2009-12-01

    The NOAA/ESRL team at South Pole has been monitoring the development of the annual ozone hole over two decades using balloon-borne and ground based instruments. Collaboration with educators has become an important aspect of NOAA/ESRL to educate the public about ozone loss and ozone hole formation. Researcher Bryan Johnson and educator Elke Bergholz worked together at South Pole in 1998/1999 as part of the NSF teacher outreach program called Teachers Experiencing Antarctica (TEA).It has been almost a decade when they collaborated again concerning the ozone changes at South Pole as part of the International Polar Year (IPY) and the PolarTREC ( http://wwpolartrec.com ) teacher outreach program sponsored by NSF. The TEA and PolarTREC programs selected teachers to travel to polar locations to work with research scientists collecting data and running experiments at various Arctic and Antarctic field sites, including Elke Bergholz working at the South Pole with the NOAA/ESRL team. While in the field, daily contact with classrooms and students around the globe was done through the internet journals, answering emails from students, and webinars. This has been followed up with presentations to schools and the public relating Ms. Bergholz’s experience and new “hands-on” understanding of ozone instruments and ozone depletion over Antarctica, and discussing what changes in the ozone we have seen at South Pole since the first outreach program nearly a decade ago. The lesson plans are available through the PolarTREC website or by contacting Elke Bergholz at ebergholz@unis.org.

  5. Adventures in Celestial Mechanics

    CERN Document Server

    Szebehely, Victor G

    1998-01-01

    A fascinating introduction to the basic principles of orbital mechanics. It has been three hundred years since Isaac Newton first formulated laws to explain the orbits of the Moon and the planets of our solar system. In so doing he laid the groundwork for modern science's understanding of the workings of the cosmos and helped pave the way to the age of space exploration. Adventures in Celestial Mechanics offers students an enjoyable way to become acquainted with the basic principles involved in the motions of natural and human-made bodies in space. Packed with examples in which these principle

  6. Frontiers in relativistic celestial mechanics

    CERN Document Server

    2014-01-01

    Relativistic celestial mechanics – investigating the motion celestial bodies under the influence of general relativity – is a major tool of modern experimental gravitational physics. With a wide range of prominent authors from the field, this two-volume series consists of reviews on a multitude of advanced topics in the area of relativistic celestial mechanics – starting from more classical topics such as the regime of asymptotically-flat spacetime, light propagation and celestial ephemerides, but also including its role in cosmology and alternative theories of gravity as well as modern experiments in this area.

  7. CANDIDATE CLUSTERS OF GALAXIES AT z > 1.3 IDENTIFIED IN THE SPITZER SOUTH POLE TELESCOPE DEEP FIELD SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Rettura, A.; Stern, D. [Jet Propulsion Laboratory, California Institute of Technology, MS 169-234, Pasadena, CA 91109 (United States); Martinez-Manso, J.; Gettings, D.; Gonzalez, A. H. [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States); Mei, S. [GEPI, Observatoire de Paris, Section de Meudon, Meudon Cedex (France); Ashby, M. L. N. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Brodwin, M. [Department of Physics and Astronomy, University of Missouri, Kansas City, MO 64110 (United States); Stanford, S. A. [Department of Physics, University of California, Davis, CA 95616 (United States); Bartlett, J. G. [APC, AstroParticule et Cosmologie, Universite Paris Diderot, CNRS/IN2P3, CEA/lrfu, Observatoire de Paris, Sorbonne Paris Cite, 75205 Paris Cedex 13 (France)

    2014-12-20

    We present 279 galaxy cluster candidates at z > 1.3 selected from the 94 deg{sup 2} Spitzer South Pole Telescope Deep Field (SSDF) survey. We use a simple algorithm to select candidate high-redshift clusters of galaxies based on Spitzer/IRAC mid-infrared data combined with shallow all-sky optical data. We identify distant cluster candidates adopting an overdensity threshold that results in a high purity (80%) cluster sample based on tests in the Spitzer Deep, Wide-Field Survey of the Boötes field. Our simple algorithm detects all three 1.4 < z ≤ 1.75 X-ray detected clusters in the Boötes field. The uniqueness of the SSDF survey resides not just in its area, one of the largest contiguous extragalactic fields observed with Spitzer, but also in its deep, multi-wavelength coverage by the South Pole Telescope (SPT), Herschel/SPIRE, and XMM-Newton. This rich data set will allow direct or stacked measurements of Sunyaev-Zel'dovich effect decrements or X-ray masses for many of the SSDF clusters presented here, and enable a systematic study of the most distant clusters on an unprecedented scale. We measure the angular correlation function of our sample and find that these candidates show strong clustering. Employing the COSMOS/UltraVista photometric catalog in order to infer the redshift distribution of our cluster selection, we find that these clusters have a comoving number density n{sub c}=(0.7{sub −0.6}{sup +6.3})×10{sup −7} h{sup 3} Mpc{sup −3} and a spatial clustering correlation scale length r {sub 0} = (32 ± 7) h {sup –1} Mpc. Assuming our sample is comprised of dark matter halos above a characteristic minimum mass, M {sub min}, we derive that at z = 1.5 these clusters reside in halos larger than M{sub min}=1.5{sub −0.7}{sup +0.9}×10{sup 14} h{sup −1} M{sub ⊙}. We find that the mean mass of our cluster sample is equal to M{sub mean}=1.9{sub −0.8}{sup +1.0}×10{sup 14} h{sup −1} M{sub ⊙}; thus, our sample contains the progenitors of

  8. Solar irradiance at the Earth's surface: long-term behavior observed at the South Pole

    Directory of Open Access Journals (Sweden)

    J. E. Frederick

    2010-11-01

    Full Text Available This research examines a 17-year database of UV-A (320–400 nm and visible (400–600 nm solar irradiance obtained by a scanning spectroradiometer located at the South Pole. The goal is to define the variability in solar irradiance reaching the polar surface, with emphasis on the influence of cloudiness and on identifying systematic trends and possible links to the solar cycle. To eliminate changes associated with the varying solar elevation, the analysis focuses on data averaged over 30–35 day periods centered on each year's austral summer solstice. The long-term average effect of South Polar clouds is a small attenuation, with the mean measured irradiances being about 5–6% less than the clear-sky values, although at any specific time clouds may reduce or enhance the signal that reaches the sensor. The instantaneous fractional attenuation or enhancement is wavelength dependent, where the percent deviation from the clear-sky irradiance at 400–600 nm is typically 2.5 times that at 320–340 nm. When averaged over the period near each year's summer solstice, significant correlations appear between irradiances at all wavelengths and the solar cycle as measured by the 10.7 cm solar radio flux. An approximate 1.8 ± 1.0% decrease in ground-level irradiance occurs from solar maximum to solar minimum for the wavelength band 320–400 nm. The corresponding decrease for 400–600 nm is 2.4 ± 1.9%. The best-estimate declines appear too large to originate in the sun. If the correlations have a geophysical origin, they suggest a small variation in atmospheric attenuation with the solar cycle over the period of observation, with the greatest attenuation occurring at solar minimum.

  9. Detection of B-mode Polarization in the Cosmic Microwave Background with Data from the South Pole Telescope

    CERN Document Server

    Hanson, D; Crites, A; Ade, P A R; Aird, K A; Austermann, J E; Beall, J A; Bender, A N; Benson, B A; Bleem, L E; Bock, J J; Carlstrom, J E; Chang, C L; Chiang, H C; Cho, H-M; Conley, A; Crawford, T M; de Haan, T; Dobbs, M A; Everett, W; Gallicchio, J; Gao, J; George, E M; Halverson, N W; Harrington, N; Henning, J W; Hilton, G C; Holder, G P; Holzapfel, W L; Hrubes, J D; Huang, N; Hubmayr, J; Irwin, K D; Keisler, R; Knox, L; Lee, A T; Leitch, E; Li, D; Liang, C; Luong-Van, D; Marsden, G; McMahon, J J; Mehl, J; Meyer, S S; Mocanu, L; Montroy, T E; Natoli, T; Nibarger, J P; Novosad, V; Padin, S; Pryke, C; Reichardt, C L; Ruhl, J E; Saliwanchik, B R; Sayre, J T; Schaffer, K K; Schulz, B; Smecher, G; Stark, A A; Story, K; Tucker, C; Vanderlinde, K; Vieira, J D; Viero, M P; Wang, G; Yefremenko, V; Zahn, O; Zemcov, M

    2013-01-01

    Gravitational lensing of the cosmic microwave background generates a curl pattern in the observed polarization. This "B-mode" signal provides a measure of the projected mass distribution over the entire observable Universe and also acts as a contaminant for the measurement of primordial gravity-wave signals. In this letter we present the first detection of gravitational lensing B modes, using first-season data from the polarization-sensitive receiver on the South Pole Telescope (SPTpol). We construct a template for the lensing B-mode signal by combining E-mode polarization measured by SPTpol with estimates of the lensing potential from a Herschel-SPIRE map of the cosmic infrared background. We compare this template to the B modes measured directly by SPTpol, finding a non-zero correlation at 7.7 sigma significance. The correlation has an amplitude and scale-dependence consistent with theoretical expectations, is robust with respect to analysis choices, and constitutes the first measurement of a powerful cosmo...

  10. A Measurement of Gravitational Lensing of the Cosmic Microwave Background by Galaxy Clusters Using Data from the South Pole Telescope

    CERN Document Server

    Baxter, E J; Dodelson, S; Aird, K A; Allen, S W; Ashby, M L N; Bautz, M; Bayliss, M; Benson, B A; Bleem, L E; Bocquet, S; Brodwin, M; Carlstrom, J E; Chang, C L; Chiu, I; Cho, H-M; Clocchiatti, A; Crawford, T M; Crites, A T; Desai, S; Dietrich, J P; de Haan, T; Dobbs, M A; Foley, R J; Forman, W R; George, E M; Gladders, M D; Gonzalez, A H; Halverson, N W; Harrington, N L; Hennig, C; Hoekstra, H; Holder, G P; Holzapfel, W L; Hou, Z; Hrubes, J D; Jones, C; Knox, L; Lee, A T; Leitch, E M; Liu, J; Lueker, M; Luong-Van, D; Mantz, A; Marrone, D P; McDonald, M; McMahon, J J; Meyer, S S; Millea, M; Mocanu, L M; Murray, S S; Padin, S; Pryke, C; Reichardt, C L; Rest, A; Ruhl, J E; Saliwanchik, B R; Saro, A; Sayre, J T; Schaffer, K K; Shirokoff, E; Song, J; Spieler, H G; Stalder, B; Stanford, S A; Staniszewski, Z; Stark, A A; Story, K T; van Engelen, A; Vanderlinde, K; Vieira, J D; Vikhlinin, A; Williamson, R; Zahn, O; Zenteno, A

    2014-01-01

    Clusters of galaxies are expected to gravitationally lens the cosmic microwave background (CMB) and thereby generate a distinct signal in the CMB on arcminute scales. Measurements of this effect can be used to constrain the masses of galaxy clusters using CMB data alone. Here we present a measurement of lensing of the CMB by galaxy clusters using data from the South Pole Telescope (SPT). We develop a maximum likelihood approach to extract the CMB cluster lensing signal and validate the method on mock data. We quantify the effects of several potential sources of systematic error and find that they generally act to reduce the best-fit cluster mass. The net magnitude of the systematic shift to lower cluster mass is approximately the size of our statistical error bar, and we do not attempt to correct for it. We apply the maximum likelihood technique to 513 clusters selected via their SZ signatures in SPT data, and rule out the null hypothesis of no lensing at 3.0$\\sigma$. The lensing-derived mass estimate for the...

  11. Constraints on Primordial Magnetic Fields from Planck combined with the South Pole Telescope CMB B-mode polarization measurements

    CERN Document Server

    Zucca, Alex; Pogosian, Levon

    2016-01-01

    A primordial magnetic field (PMF) present before recombination can leave specific signatures on the cosmic microwave background (CMB) fluctuations. Of particular importance is its contribution to the B-mode polarization power spectrum. Indeed, vortical modes sourced by the PMF can dominate the B-mode power spectrum on small scales, as they survive damping up to a small fraction of the Silk length. Therefore, measurements of the B-mode polarization at high-$\\ell$ , such as the one recently performed by the South Pole Telescope (SPT), have the potential to provide stringent constraints on the PMF. We use the publicly released SPT B-mode polarization spectrum, along with the temperature and polarization data from the Planck satellite, to derive constraints on the magnitude, the spectral index and the energy scale at which the PMF was generated. We find that, while Planck data constrains the magnetic amplitude to $B_{1 \\, \\text{Mpc}} < 3.3$ nG at 95\\% confidence level (CL), the SPT measurement improves the con...

  12. Local Lunar Gravity Field Analysis over the South Pole-aitken Basin from SELENE Farside Tracking Data

    Science.gov (United States)

    Goossens, Sander Johannes; Ishihara, Yoshiaki; Matsumoto, Koji; Sasaki, Sho

    2012-01-01

    We present a method with which we determined the local lunar gravity field model over the South Pole-Aitken (SPA) basin on the farside of the Moon by estimating adjustments to a global lunar gravity field model using SELENE tracking data. Our adjustments are expressed in localized functions concentrated over the SPA region in a spherical cap with a radius of 45deg centered at (191.1 deg E, 53.2 deg S), and the resolution is equivalent to a 150th degree and order spherical harmonics expansion. The new solution over SPA was used in several applications of geophysical analysis. It shows an increased correlation with high-resolution lunar topography in the frequency band l = 40-70, and admittance values are slightly different and more leveled when compared to other, global gravity field models using the same data. The adjustments expressed in free-air anomalies and differences in Bouguer anomalies between the local solution and the a priori global solution correlate with topographic surface features. The Moho structure beneath the SPA basin is slightly modified in our solution, most notably at the southern rim of the Apollo basin and around the Zeeman crater

  13. Basin and Crater Ejecta Contributions to the South Pole-Aitken Basin (SPA) Regolith; Positive Implications for Robotic Surface Samples

    Science.gov (United States)

    Petro, Noah E.; Jolliff, B. L.

    2011-01-01

    The ability of impacts of all sizes to laterally transport ejected material across the lunar surface is well-documented both in lunar samples [1-4] and in remote sensing data [5-7]. The need to quantify the amount of lateral transport has lead to several models to estimate the scale of this effect. Such models have been used to assess the origin of components at the Apollo sites [8-10] or to predict what might be sampled by robotic landers [11-13]. Here we continue to examine the regolith inside the South Pole-Aitken Basin (SPA) and specifically assess the contribution to the SPA regolith by smaller craters within the basin. Specifically we asses the effects of four larger craters within SPA, Bose, Bhabha, Stoney, and Bellinsgauzen all located within the mafic enhancement in the center of SPA (Figure 1). The region around these craters is of interest as it is a possible landing and sample return site for the proposed Moon-Rise mission [14-17]. Additionally, understanding the provenance of components in the SPA regolith is important for interpreting remotely sensed data of the basin interior [18-20].

  14. ALMA Imaging and Gravitational Lens Models of South Pole Telescope-Selected Dusty, Star-Forming Galaxies at High Redshifts

    CERN Document Server

    Spilker, Justin; Aravena, Manuel; Bethermin, Matthieu; Bothwell, Matt; Carlstrom, John; Chapman, Scott; Crawford, Tom; de Breuck, Carlos; Fassnacht, Chris; Gonzalez, Anthony; Greve, Thomas; Hezaveh, Yashar; Litke, Katrina; Ma, Jingzhe; Malkan, Matt; Rotermund, Kaja; Strandet, Maria; Vieira, Joaquin; Weiss, Axel; Welikala, Niraj

    2016-01-01

    The South Pole Telescope has discovered one hundred gravitationally lensed, high-redshift, dusty, star-forming galaxies (DSFGs). We present 0.5" resolution 870um Atacama Large Millimeter/submillimeter Array imaging of a sample of 47 DSFGs spanning z=1.9-5.7, and construct gravitational lens models of these sources. Our visibility-based lens modeling incorporates several sources of residual interferometric calibration uncertainty, allowing us to properly account for noise in the observations. At least 70% of the sources are strongly lensed by foreground galaxies (mu_870um > 2), with a median magnification mu_870um = 6.3, extending to mu_870um > 30. We compare the intrinsic size distribution of the strongly lensed sources to a similar number of unlensed DSFGs and find no significant differences in spite of a bias between the magnification and intrinsic source size. This may indicate that the true size distribution of DSFGs is relatively narrow. We use the source sizes to constrain the wavelength at which the du...

  15. Gaia Data Release 1 - The Cepheid & RR Lyrae star pipeline and its application to the south ecliptic pole region

    CERN Document Server

    Clementini, G; Leccia, S; Mowlavi, N; Lecoeur-Taibi, I; Marconi, M; Szabados, L; Eyer, L; Guy, L P; Rimoldini, L; de Fombelle, G Jevardat; Holl, B; Busso, G; Charnas, J; Cuypers, J; De Angeli, F; De Ridder, J; Debosscher, J; Evans, D W; Klagyivik, P; Musella, I; Nienartowicz, K; Ordonez, D; Regibo, S; Riello, M; Sarro, L M; Suveges, M

    2016-01-01

    We present an overview of the Specific Objects Study (SOS) pipeline developed within the Coordination Unit 7 (CU7) of the Gaia Data Processing and Analysis Consortium (DPAC), the coordination unit charged with the processing and analysis of variable sources observed by Gaia, to validate and fully characterise Cepheids and RR Lyrae stars observed by the spacecraft. We describe how the SOS for Cepheids and RR Lyrae stars (SOS Cep&RRL) was specifically tailored to analyse Gaia's G-band photometric time-series with a South Ecliptic Pole (SEP) footprint, which covers an external region of the Large Magellanic Cloud (LMC). G-band time-series photometry and characterization by the SOS Cep&RRL pipeline (mean magnitude and pulsation characteristics) are published in Gaia Data Release 1 (Gaia DR1) for a total sample of 3,194 variable stars, 599 Cepheids and 2,595 RR Lyrae stars, of which 386 (43 Cepheids and 343 RR Lyrae stars) are new discoveries by Gaia. All 3,194 stars are distributed over an area extending ...

  16. Constraining AGN Feedback in Massive Ellipticals with South Pole Telescope Measurements of the Thermal Sunyaev-Zel'dovich Effect

    CERN Document Server

    Spacek, Alexander; Cohen, Seth; Joshi, Bhavin; Mauskopf, Philip

    2016-01-01

    Energetic feedback due to active galactic nuclei (AGN) is likely to play an important role in the observed anti-hierarchical trend in the evolution of galaxies, and yet the energy injected into the circumgalactic medium by this process is largely unknown. One promising approach to constrain this feedback is through measurements of CMB spectral distortions due to the thermal Sunyaev-Zel'dovich (tSZ) effect, whose magnitude is directly proportional to the energy input by AGN. Here we co-add South Pole Telescope SZ (SPT-SZ) survey data around a large set of massive quiescent elliptical galaxies at z >= 0.5. We use data from the Blanco Cosmology Survey and VISTA Hemisphere Survey to create a large catalog of galaxies split up into two redshift bins, with 3394 galaxies at 0.5 <= z <= 1.0 and 924 galaxies at 1.0 <= z <= 1.5, with typical stellar masses of 1.5 x 10^11 M_Sun. We then co-add the emission around these galaxies, resulting in a measured tSZ signal at 2.2 sigma significance for the lower redsh...

  17. SPT-3G: A Next-Generation Cosmic Microwave Background Polarization Experiment on the South Pole Telescope

    CERN Document Server

    Benson, B A; Ahmed, Z; Allen, S W; Arnold, K; Austermann, J E; Bender, A N; Bleem, L E; Carlstrom, J E; Chang, C L; Cho, H M; Ciocys, S T; Cliche, J F; Crawford, T M; Cukierman, A; de Haan, T; Dobbs, M A; Dutcher, D; Everett, W; Gilbert, A; Halverson, N W; Hanson, D; Harrington, N L; Hattori, K; Henning, J W; Hilton, G C; Holder, G P; Holzapfel, W L; Irwin, K D; Keisler, R; Knox, L; Kubik, D; Kuo, C L; Lee, A T; Leitch, E M; Li, D; McDonald, M; Meyer, S S; Montgomery, J; Myers, M; Natoli, T; Nguyen, H; Novosad, V; Padin, S; Pan, Z; Pearson, J; Reichardt, C L; Ruhl, J E; Saliwanchik, B R; Simard, G; Smecher, G; Sayre, J T; Shirokoff, E; Stark, A A; Story, K; Suzuki, A; Thompson, K L; Tucker, C; Vanderlinde, K; Vieira, J D; Vikhlinin, A; Wang, G; Yefremenko, V; Yoon, K W

    2014-01-01

    We describe the design of a new polarization sensitive receiver, SPT-3G, for the 10-meter South Pole Telescope (SPT). The SPT-3G receiver will deliver a factor of ~20 improvement in mapping speed over the current receiver, SPTpol. The sensitivity of the SPT-3G receiver will enable the advance from statistical detection of B-mode polarization anisotropy power to high signal-to-noise measurements of the individual modes, i.e., maps. This will lead to precise (~0.06 eV) constraints on the sum of neutrino masses with the potential to directly address the neutrino mass hierarchy. It will allow a separation of the lensing and inflationary B-mode power spectra, improving constraints on the amplitude and shape of the primordial signal, either through SPT-3G data alone or in combination with BICEP-2/KECK, which is observing the same area of sky. The measurement of small-scale temperature anisotropy will provide new constraints on the epoch of reionization. Additional science from the SPT-3G survey will be significantl...

  18. The geometry of celestial mechanics

    CERN Document Server

    Geiges, Hansjörg

    2016-01-01

    Celestial mechanics is the branch of mathematical astronomy devoted to studying the motions of celestial bodies subject to the Newtonian law of gravitation. This mathematical introductory textbook reveals that even the most basic question in celestial mechanics, the Kepler problem, leads to a cornucopia of geometric concepts: conformal and projective transformations, spherical and hyperbolic geometry, notions of curvature, and the topology of geodesic flows. For advanced undergraduate and beginning graduate students, this book explores the geometric concepts underlying celestial mechanics and is an ideal companion for introductory courses. The focus on the history of geometric ideas makes it perfect supplementary reading for students in elementary geometry and topology. Numerous exercises, historical notes and an extensive bibliography provide all the contextual information required to gain a solid grounding in celestial mechanics.

  19. Extending the X/Ka Celestial Reference Frame over the South Polar Cap: Results from combined NASA-ESA Deep Space Network baselines to Malargüe, Argentina

    Science.gov (United States)

    Jacobs, Christopher S.; de Vicente, J.; Dugast, M.; García-Miró, C.; Goodhart, C. E.; Horiuchi, S.; Lowe, S. T.; Maddè, R.; Mercolino, M.; Naudet, C. J.; Snedeker, L. G.; Sotuela, I.; White, L. A.

    2013-03-01

    In order to extend the X/Ka-band (8.4/32 GHz) Celestial Reference Frame coverage over the south polar cap region of declinations -45 to -90 deg, we developed a collaboration between the NASA and ESA Deep Space Networks. In particular ESA's new 35-meter X/Ka-band antenna in Malargüe, Argentina which became operational in January 2013 is now available for X/Ka VLBI baselines to NASA's antennas in Tidbinbilla, Australia; Goldstone, California; and Robledo, Spain. We report first fringes on baselines from Malargüe to Tidbinbilla, Goldstone, and Robledo using a semi-portable digital backend recording at 256 Mbps. To the best of our knowledge the Giga-lambda Malargüe-Tidbinbilla baseline is producing the highest resolution interferometry ever achieved over the south polar cap. We will present the distribution of Ka-band sources detected on this all-southern baseline. Lastly, we will discuss the prospects for using these new baselines to improve the astrometric accuracy of the X/Ka frame in the southern hemisphere.

  20. An introduction to celestial mechanics

    CERN Document Server

    Moulton, Forest Ray

    1984-01-01

    An unrivaled text in the field of celestial mechanics, Moulton's theoretical work on the prediction and interpretation of celestial phenomena has not been superseded. By providing a general account of all parts of celestial mechanics without an over-full treatment of any single aspect, by stating all the problems in advance, and, where the transformations are long, giving an outline of the steps which must be made, and by noting all the places where assumptions have been introduced or unjustified methods employed, Moulton has insured that his work will be valuable to all who are interested in

  1. ALMA Imaging and Gravitational Lens Models of South Pole Telescope—Selected Dusty, Star-Forming Galaxies at High Redshifts

    Science.gov (United States)

    Spilker, J. S.; Marrone, D. P.; Aravena, M.; Béthermin, M.; Bothwell, M. S.; Carlstrom, J. E.; Chapman, S. C.; Crawford, T. M.; de Breuck, C.; Fassnacht, C. D.; Gonzalez, A. H.; Greve, T. R.; Hezaveh, Y.; Litke, K.; Ma, J.; Malkan, M.; Rotermund, K. M.; Strandet, M.; Vieira, J. D.; Weiss, A.; Welikala, N.

    2016-08-01

    The South Pole Telescope has discovered 100 gravitationally lensed, high-redshift, dusty, star-forming galaxies (DSFGs). We present 0.″5 resolution 870 μ {{m}} Atacama Large Millimeter/submillimeter Array imaging of a sample of 47 DSFGs spanning z=1.9{--}5.7, and construct gravitational lens models of these sources. Our visibility-based lens modeling incorporates several sources of residual interferometric calibration uncertainty, allowing us to properly account for noise in the observations. At least 70% of the sources are strongly lensed by foreground galaxies ({μ }870μ {{m}}\\gt 2), with a median magnification of {μ }870μ {{m}}=6.3, extending to {μ }870μ {{m}}\\gt 30. We compare the intrinsic size distribution of the strongly lensed sources to a similar number of unlensed DSFGs and find no significant differences in spite of a bias between the magnification and intrinsic source size. This may indicate that the true size distribution of DSFGs is relatively narrow. We use the source sizes to constrain the wavelength at which the dust optical depth is unity and find this wavelength to be correlated with the dust temperature. This correlation leads to discrepancies in dust mass estimates of a factor of two compared to estimates using a single value for this wavelength. We investigate the relationship between the [C ii] line and the far-infrared luminosity and find that the same correlation between the [C ii]/{L}{{FIR}} ratio and {{{Σ }}}{{FIR}} found for low-redshift star-forming galaxies applies to high-redshift galaxies and extends at least two orders of magnitude higher in {{{Σ }}}{{FIR}}. This lends further credence to the claim that the compactness of the IR-emitting region is the controlling parameter in establishing the “[C ii] deficit.”

  2. Galaxy populations in the 26 most massive galaxy clusters in the South Pole Telescope SPT-SZ survey

    Science.gov (United States)

    Zenteno, A.; Mohr, J. J.; Desai, S.; Stalder, B.; Saro, A.; Dietrich, J. P.; Bayliss, M.; Bocquet, S.; Chiu, I.; Gonzalez, A. H.; Gangkofner, C.; Gupta, N.; Hlavacek-Larrondo, J.; McDonald, M.; Reichardt, C.; Rest, A.

    2016-10-01

    We present a study of the optical properties of the 26 most massive galaxy clusters within the South Pole Telescope Sunyaev-Zel'dovich (SPT-SZ) 2500 deg2 survey spanning the redshift range 0.10 luminosity functions (LFs), and the halo occupation numbers (HONs) using optical data of typical depth m* + 2. The stacked radial profiles are consistent with a Navarro-Frenk-White profile of concentration 2.84^{+0.40}_{-0.37} for the red sequence (RS) and 2.36^{+0.38}_{-0.35} for the total population. Stacking the data in multiple redshift bins shows slight redshift evolution in the concentration when both the total population is used, and when only RS galaxies are used (at 2.1σ and 2.8σ, respectively). The stacked LF shows a faint end slope α = -1.06^{+0.04}_{-0.03} for the total and α = -0.80^{+0.04}_{-0.03} for the RS population. The redshift evolution of m* is consistent with a passively evolving composite stellar population (CSP) model. Adopting the CSP model predictions, we explore the redshift evolution of the Schechter parameters α and φ*. We find α for the total population to be consistent with no evolution (0.3σ), and mildly significant evidence of evolution for the red galaxies (1.1-2.1σ). The data show that the density φ*/E2(z) decreases with redshift, in tension with the self-similar expectation at a 2.4σ level for the total population. The measured HON-mass relation has a lower normalization than previous low redshift studies. Finally, our data support HON redshift evolution at a 2.1σ level, with clusters at higher redshift containing fewer galaxies than their low-z counterparts.

  3. SIMULATION OF EARTH'S POLES DYNAMICS USING ASK-ANALYSIS

    Directory of Open Access Journals (Sweden)

    Cherednychenko N. A.

    2014-05-01

    Full Text Available Based on local semantic information models, we have examined the dependence of the dynamics of the displacement of the pole positions of celestial objects. We have also developed and differentiated an analysis of ASK-pole modeling of dynamics within sixty-year cycles of reference points and substantiated reasons for the population inversion and singular states in the dynamics of the pole

  4. Ulysses COSPIN observations of cosmic rays and solar energetic particles from the South Pole to the North Pole of the Sun during solar maximum

    Directory of Open Access Journals (Sweden)

    R. B. McKibben

    Full Text Available In 2000–2001 Ulysses passed from the south to the north polar regions of the Sun in the inner heliosphere, providing a snapshot of the latitudinal structure of cosmic ray modulation and solar energetic particle populations during a period near solar maximum.  Observations from the COSPIN suite of energetic charged particle telescopes show that latitude variations in the cosmic ray intensity in the inner heliosphere are nearly non-existent near solar maximum, whereas small but clear latitude gradients were observed during the similar phase of Ulysses’ orbit near the 1994–95 solar minimum. At proton energies above ~10 MeV and extending up to >70 MeV, the intensities are often dominated by Solar Energetic Particles (SEPs accelerated near the Sun in association with intense solar flares and large Coronal Mass Ejections (CMEs. At lower energies the particle intensities are almost constantly enhanced above background, most likely as a result of a mix of SEPs and particles accelerated by interplanetary shocks. Simultaneous high-latitude Ulysses and near-Earth observations show that most events that produce large flux increases near Earth also produce flux increases at Ulysses, even at the highest latitudes attained. Particle anisotropies during particle onsets at Ulysses are typically directed outwards from the Sun, suggesting either acceleration extending to high latitudes or efficient cross-field propagation somewhere inside the orbit of Ulysses. Both cosmic ray and SEP observations are consistent with highly efficient transport of energetic charged particles between the equatorial and polar regions and across the mean interplanetary magnetic fields in the inner heliosphere.

    Key words. Interplanetary physics (cosmic rays – Solar physics, astrophysics and astronomy (energetic particles; flares and mass ejections

  5. Organized flow from the South Pole to the Filchner-Ronne ice shelf: An assessment of balance velocities in interior East Antarctica using radio echo sounding data

    Science.gov (United States)

    Bingham, Robert G.; Siegert, Martin J.; Young, Duncan A.; Blankenship, Donald D.

    2007-09-01

    Ice flow through central Antarctica has the potential to transmit accumulation changes from deep-interior East Antarctica rapidly to the shelf, but it is poorly constrained owing to a dearth of ice-velocity observations. We use parameters derived from airborne radio echo sounding (RES) data to examine the onset, areal extent, and englacial conditions of an organized flow network (tributaries feeding an ice stream) draining from the South Pole to the Filchner-Ronne Ice Shelf. We classified RES flight tracks covering the region according to whether englacial stratigraphy was disrupted (i.e., internal layers diverged significantly from the surface and bed echoes) or undisrupted (i.e., internal layers closely parallel surface and basal topography), and we calculated subglacial roughness along basal reflectors. Where satellite-measured surface ice-flow speeds are available (covering 39% of the study region), regions of fast and tributary flow correspond with RES flight tracks that exhibit more disrupted internal layers and smoother subglacial topography than their counterparts in regions of slow flow. This suggests that disrupted internal layering and smooth subglacial topography identified from RES profiles can be treated as indicators of past or present enhanced-flow tributaries where neither satellite nor ground-based ice-flow measurements are available. We therefore use these RES-derived parameters to assess the balance-flux-modeled steady state flow regime between the South Pole and Filchner-Ronne Ice Shelf. The RES analysis confirms that an organized flow network drains a wide region around the South Pole into the Filchner-Ronne Ice Shelf. However, the spatial extent of this network, as delineated by the RES data, diverges from that predicted by currently available balance-flux models.

  6. Constraining AGN Feedback in Massive Ellipticals with South Pole Telescope Measurements of the Thermal Sunyaev-Zel'dovich Effect

    Science.gov (United States)

    Spacek, Alexander; Scannapieco, Evan; Cohen, Seth; Joshi, Bhavin; Mauskopf, Philip

    2016-03-01

    Energetic feedback due to active galactic nuclei (AGNs) is likely to play an important role in the observed anti-hierarchical trend in the evolution of galaxies, and yet the energy injected into the circumgalactic medium by this process is largely unknown. One promising approach to constrain this feedback is through measurements of spectral distortions in the cosmic microwave background due to the thermal Sunyaev-Zeldovich (tSZ) effect, whose magnitude is directly proportional to the energy input by AGNs. With current instruments, making such measurements requires stacking large numbers of objects to increase signal-to-noise. While one possible target for such stacks is AGNs themselves, these are relatively scarce sources that contain contaminating emission that complicates tSZ measurements. Here we adopt an alternative approach and co-add South Pole Telescope SZ (SPT-SZ) survey data around a large set of massive quiescent elliptical galaxies at z≥slant 0.5, which are much more numerous and less contaminated than active AGNs, yet are subject to the same feedback processes from the AGNs they hosted in the past. We use data from the Blanco Cosmology Survey and VISTA Hemisphere Survey to create a large catalog of galaxies split up into two redshift bins: one with 3394 galaxies at 0.5≤slant z≤slant 1.0 and one with 924 galaxies at 1.0≤slant z≤slant 1.5, with typical stellar masses of 1.5× {10}11{M}⊙ . We then co-add the emission around these galaxies, resulting in a measured tSZ signal at 2.2σ significance for the lower redshift bin and a contaminating signal at 1.1σ for the higher redshift bin. To remove contamination due to dust emission, we use SPT-SZ source counts to model a contaminant source population in both the SPT-SZ bands and Planck high-frequency bands for a subset of 937 galaxies in the low-redshift bin and 240 galaxies in the high-redshift bin. This increases our detection to 3.6σ for low redshifts and 0.9σ for high redshifts. We find the

  7. Celestial navigation in a nutshell

    CERN Document Server

    Schlereth, Hewitt

    2000-01-01

    Celestial Navigation in a Nutshell demonstrates how to take sights by the sun, moon, stars, and planets, discussing the advantages and disadvantages of each method. The reader is taken carefully through several examples and situational illustrations, making this a most effective self-teaching guide. Common errors are reviewed and several tips on how to improve accuracy are given.

  8. Celestial mechanics with geometric algebra

    Science.gov (United States)

    Hestenes, D.

    1983-01-01

    Geometric algebra is introduced as a general tool for Celestial Mechanics. A general method for handling finite rotations and rotational kinematics is presented. The constants of Kepler motion are derived and manipulated in a new way. A new spinor formulation of perturbation theory is developed.

  9. Observation of Celestial Phenomena in Ancient China

    Science.gov (United States)

    Sun, Xiaochun

    Because of the need for calendar-making and portent astrology, the Chinese were diligent and meticulous observers of celestial phenomena. China has maintained the longest continuous historical records of celestial phenomena in the world. Extraordinary or abnormal celestial events were particularly noted because of their astrological significance. The historical records cover various types of celestial phenomena, which include solar and lunar eclipses, sunspots, "guest stars" (novae or supernovae as we understand today), comets and meteors, and all kinds of planetary phenomena. These records provide valuable historical data for astronomical studies today.

  10. Probing star formation in the dense environments of z~1 lensing halos aligned with dusty star-forming galaxies detected with the South Pole Telescope

    CERN Document Server

    Welikala, N; Guery, D; Strandet, M; Aird, K A; Aravena, M; Ashby, M L N; Bothwell, M; Beelen, A; Bleem, L E; de Breuck, C; Brodwin, M; Carlstrom, J E; Chapman, S C; Crawford, T M; Dole, H; Doré, O; Everett, W; Flores-Cacho, I; Gonzalez, A H; González-Nuevo, J; Greve, T R; Gullberg, B; Hezaveh, Y D; Holder, G P; Holzapfel, W L; Keisler, R; Lagache, G; Ma, J; Malkan, M; Marrone, D P; Mocanu, L M; Montier, L; Murphy, E J; Nesvadba, N P H; Omont, A; Pointecouteau, E; Puget, J L; Reichardt, C L; Rotermund, K M; Scott, D; Serra, P; Spilker, J S; Stalder, B; Stark, A A; Story, K; Vanderlinde, K; Vieira, J D; Weiss, A

    2015-01-01

    We probe star formation in the environments of massive $\\sim10^{13}\\,M_{\\odot}$ dark matter halos at redshifts of $z$$\\sim$$1$. This star formation is linked to a sub-millimetre clustering signal which we detect in maps of the Planck High Frequency Instrument that are stacked at the positions of a sample of high-redshift ($z$$>$$2$) strongly-lensed dusty star-forming galaxies (DSFGs) selected from the South Pole Telescope (SPT) 2500 deg$^2$ survey. The clustering signal has sub-millimetre colours which are consistent with the mean redshift of the foreground lensing halos ($z$$\\sim$$1$). We report a mean excess of star formation rate (SFR) compared to the field, of $(2700\\pm700)\\,M_{\\odot}\\,{yr}^{-1}$ from all galaxies contributing to this clustering signal within a radius of 3.5' from the SPT DSFGs. The magnitude of the Planck excess is in broad agreement with predictions of a current model of the cosmic infrared background. The model predicts that 80$\\%$ of the excess emission measured by Planck originates f...

  11. Thermal behavior of regolith at cold traps on the moon's south pole: Revealed by Chang'E-2 microwave radiometer data

    Science.gov (United States)

    Wei, Guangfei; Li, Xiongyao; Wang, Shijie

    2016-03-01

    The long-term stability of water ice at cold traps depends on subsurface temperature and regolith thermophysical properties. Based on Chang'E-2 microwave radiometer data, we have inverted attenuation coefficient, thermal gradient and instantaneous temperature profiles at permanently shaded craters (Cabeus, Haworth and Shoemaker) on the Moon's south pole. The nonuniformity of the inverted attenuation coefficient within the craters reflects the inhomogeneous thermophysical properties of regolith. In addition, thermal gradient decreased significantly from the crater walls to the bottoms, which may be caused by scattered sunlight, internal heat flux and earthshine effect. Considering continuous supplement of water ice (with volumetric fraction 0-10%) at cold traps, it changes subsurface thermophysical properties but has little effect on thermal gradient. We also assumed that abundant ice (10%) mixed with regolith, the inversion results showed that the maximum difference of diurnal temperatures between "wet" and dry regolith were no more than 0.5 K. That is, the effect of water ice on subsurface thermal behavior can be neglected.

  12. Constraints on the CMB Temperature Evolution using Multi-Band Measurements of the Sunyaev Zel'dovich Effect with the South Pole Telescope

    CERN Document Server

    Saro, A; Mohr, J J; Aird, K A; Ashby, M L N; Bayliss, M; Benson, B A; Bleem, L E; Bocquet, S; Brodwin, M; Carlstrom, J E; Chang, C L; Chiu, I; Cho, H M; Clocchiatti, A; Crawford, T M; Crites, A T; de Haan, T; Desai, S; Dietrich, J P; Dobbs, M A; Dolag, K; Dudley, J P; Foley, R J; Gangkofner, D; George, E M; Gladders, M D; Gonzalez, A H; Halverson, N W; Hennig, C; Holzapfel, W L; Hrubes, J D; Jones, C; Keisler, R; Lee, A T; Leitch, E M; Lueker, M; Luong-Van, D; Mantz, A; Marrone, D P; McDonald, M; McMahon, J J; Mehl, J; Meyer, S S; Mocanu, L; Montroy, T E; Murray, S S; Nurgaliev, D; Padin, S; Patej, A; Pryke, C; Reichardt, C L; Rest, A; Ruel, J; Ruhl, J E; Saliwanchik, B R; Sayre, J T; Schaffer, K K; Shirokoff, E; Spieler, H G; Stalder, B; Staniszewski, Z; Stark, A A; Story, K; van Engelen, A; Vanderlinde, K; Vieira, J D; Vikhlinin, A; Williamson, R; Zahn, O; Zenteno, A

    2013-01-01

    The adiabatic evolution of the temperature of the cosmic microwave background (CMB) is a key prediction of standard cosmology. We study deviations from the expected adiabatic evolution of the CMB temperature of the form $T(z) =T_0(1+z)^{1-\\alpha}$ using measurements of the spectrum of the Sunyaev Zel'dovich Effect with the South Pole Telescope (SPT). We present a method for using the ratio of the Sunyaev Zel'dovich signal measured at 95 and 150 GHz in the SPT data to constrain the temperature of the CMB. We demonstrate that this approach provides unbiased results using mock observations of clusters from a new set of hydrodynamical simulations. We apply this method to a sample of 158 SPT-selected clusters, spanning the redshift range $0.05 < z < 1.35$, and measure $\\alpha = 0.017^{+0.030}_{-0.028}$, consistent with the standard model prediction of $\\alpha=0$. In combination with other published results, we constrain $\\alpha = 0.011 \\pm 0.016$, an improvement of $\\sim 20\\%$ over published constraints. Thi...

  13. An elementary survey of celestial mechanics

    CERN Document Server

    Ryabov, Y

    2006-01-01

    An accessible exposition of gravitation theory and celestial mechanics, this classic, oft-cited work was written by a distinguished Soviet astronomer. It explains with exceptional clarity the methods used by physicists in studying celestial phenomena.A historical introduction explains the Ptolemaic view of planetary motion and its displacement by the studies of Copernicus, Kepler, and Newton. Succeeding chapters examine the making of celestial observations and measurements and explain such central concepts as the ecliptic, the orbital plane, the two- and three-body problems, and perturbed moti

  14. Celestial Navigation for the Novice

    Science.gov (United States)

    Sadler, Philip M.

    2011-01-01

    What kinds of astronomical lab activities can introductory astronomy students carry out easily in daytime? The most impressive is the determination of their latitude and longitude from observations of the sun. The "shooting of a noon sight” and its "reduction to a position” is a technique still practiced by navigators in this age of GPS. Indeed, the U.S. Coast Guard exams for ocean-going licenses and include celestial navigation. These techniques continue to be used by the military and by private sailors as a backup to electronic navigation systems. We present a method to establish one's latitude and longitude to better than 30 miles from measurements of the sun's altitude that is easily within the capability non-science majors. This is a practical application of astronomy in use the world over. The streamlined method used is based on an easy-to-build protractor and string quadrant. Participants will leave with all materials to conduct this activity in their own classroom.

  15. Connecting VLBI and Gaia celestial reference frames

    CERN Document Server

    Malkin, Zinovy

    2016-01-01

    The current state of the link problem between radio and optical celestial reference frames is considered. The main objectives of the investigations in this direction during the next few years are the preparation of a comparison and the mutual orientation and rotation between the optical {\\it Gaia} Celestial Reference Frame (GCRF) and the 3rd generation radio International Celestial Reference Frame (ICRF3), obtained from VLBI observations. Both systems, ideally, should be a realization of the ICRS (International Celestial Reference System) at micro-arcsecond level accuracy. Therefore, the link accuracy between the ICRF and GCRF should be obtained with similar error level, which is not a trivial task due to relatively large systematic and random errors in source positions at different frequency bands. In this paper, a brief overview of recent work on the GCRF--ICRF link is presented. Additional possibilities to improve the GCRF--ICRF link accuracy are discussed. The suggestion is made to use astrometric radio s...

  16. Celestial mechanics and astrodynamics theory and practice

    CERN Document Server

    Gurfil, Pini

    2016-01-01

    This volume is designed as an introductory text and reference book for graduate students, researchers and practitioners in the fields of astronomy, astrodynamics, satellite systems, space sciences and astrophysics. The purpose of the book is to emphasize the similarities between celestial mechanics and astrodynamics, and to present recent advances in these two fields so that the reader can understand the inter-relations and mutual influences. The juxtaposition of celestial mechanics and astrodynamics is a unique approach that is expected to be a refreshing attempt to discuss both the mechanics of space flight and the dynamics of celestial objects. “Celestial Mechanics and Astrodynamics: Theory and Practice” also presents the main challenges and future prospects for the two fields in an elaborate, comprehensive and rigorous manner. The book presents homogenous and fluent discussions of the key problems, rendering a portrayal of recent advances in the field together with some basic concepts and essential in...

  17. Fingerprinting Volcanic and Anthropogenic Sulfur Dioxide in the Air: A 25 Year Record of Sulfate Aerosols from the South Pole Snowpit, Antarctica

    Science.gov (United States)

    Shaheen, R.; Abaunza-Quintero, M.; Jackson, T. L.; McCabe, J.; Savarino, J. P.; Thiemens, M. H.

    2012-12-01

    Sulfate aerosols, unlike greenhouse gases, cause cooling effect (-0.4 ± 0.2 W.m-2) by scattering incoming solar radiation and by acting as cloud condensation nuclei (IPCC 2007). Volcanic eruptions with explosivity Indices >5 inject large amounts of SO2 and particles into the stratosphere causing a significant decrease in temperature. For example a 0.7oC decrease in Earth's temperature was observed following the Pinatubo eruption in 1991. Stratospheric injection of sulfate aerosols has been suggested as a geoengineering effort to mitigate global warming caused by a significant increase in greenhouse gases. To understand the impact of volcanic events on the stratospheric sulfate aerosol layer and subsequent changes in the dynamics of the upper atmosphere, a long term and high temporal resolution record of sulfate aerosol is needed. Here we present a 25 year (1978 to 2003) high resolution record of sulfate aerosols which covers largest volcanic eruptions of the 20th century namely, El-Chichón 1982 and Pinatubo 1991. Sulfate aerosol samples were obtained from a 1x1m snowpit at the South Pole, Antarctica with approximately 6 month time steps. Sulfate concentrations vary from 30 to 70 ppb depending on the season with exceptions during volcanic events which contributed a three to four folds increase in sulfate concentration Sulfate concentrations of120 ppb following El Chichón and 190 ppb after Pinatubo eruptions were observed. The oxygen isotopic anomaly varied from 0.7‰ to 3.9‰ with the highest anomaly occurring after the Pinatubo eruption. The positive Δ17O of sulfate derives from aqueous phase oxidation of SO2 by H2O2 and O3 oxidation and involves transfer of the isotopic anomaly from the oxidant to the product sulfate. Coupled with kinetic analysis the relative reaction rates the relative proportions of oxidation can be calculated. All other sulfate sources such as sea salt sulfates, primary sulfates from fossil fuel combustion, metal catalyzed oxidation of S

  18. The Blanco Cosmology Survey: Data Reduction, Calibration and Photometric Redshift Estimation to Four Distant Galaxy Clusters Discovered by the South Pole Telescope

    Science.gov (United States)

    Ngeow, Chow Choong; Mohr, J.; Zenteno, A.; Data Management, DES; BCS; SPT Collaborations

    2009-01-01

    The Blanco Cosmology Survey (BCS) is designed to enable a study of the cosmic acceleration using multiple techniques. To date, BCS has acquired Sloan griz band imaging data from 60 nights (15 nights per year from 2005 to 2008) using the Blanco 4m Telescope located at CTIO. The astronomical imaging data taken from this survey have been processed on high performance computer TeraGrid platforms at NCSA, using the automated Dark Energy Survey (DES) data management (DM) system. The DES DM system includes (1) middlewares for controlling and managing the processing jobs, and serve as an application container encapsulating the scientific codes; and (2) DES archive, which includes filesystem nodes, a relational database and a data access framework, to support the pipeline processing, data storage and scientific analyzes. Photometric solution module (PSM) were run on photometric nights to determine the zeropoints (ZP) and other photometric solutions. We remapped and coadded the images that lie within the pre-defined coadd tiles in the sky. When running the coaddition pipeline, we determined the ZP for each images using the photometric ZP from PSM, the magnitude offsets between overlapping images, and the sky brightness ratio for CCDs within a given exposure. We also applied aperture correction and color-term correction to the coadded catalogs. Satisfactory photometric and astrometric precision were achieved. These enabled initial estimation of photometric redshifts using ANNz codes, trained from 5000 galaxies with spectroscopic redshifts. RMS in the photometric redshifts ranges from 0.05 to 0.1 in sigma_z/(1+z) for redshift extended to z=1. We used the BCS data to optically confirm and estimate redshifts for four of the highest S/N galaxy clusters discovered with the South Pole Telescope using the Sunyaev-Zel'dovich Effect.

  19. Reconstruction of extensive air showers and measurement of the cosmic ray energy spectrum in the range of 1 - 80 PeV at the South Pole

    Energy Technology Data Exchange (ETDEWEB)

    Klepser, Stefan

    2008-06-24

    IceTop is a km{sup 2} scale detector array for highly energetic cosmic radiation. It is a part of the IceCube Observatory that is presently being built at the geographic South Pole. It aims for the detection of huge particle cascades induced by PeV cosmic rays in the atmosphere. These extensive air showers are detected by cylindrical ice tanks that collect the Cherenkov light produced by penetrating particles. The main goal of IceTop is the investigation of the energy distribution and chemical composition of PeV to EeV cosmic rays. This thesis presents the first analysis of highly energetic cosmic ray data taken with IceTop. First, the light response of the IceTop tanks is parametrised as a function of energy and particle type. An expectation function for the distribution of shower signals in the detector plane is developed. The likelihood fit based on that can reconstruct the recorded shower events with resolutions of 1.5 in direction, 9m in location of the shower center, and 12% in energy. This is well competitive with other experiments. The resulting energy response of the array is studied to set up response matrices for different primary nuclei and inclinations. These allow for a deconvolution of the distribution of reconstructed energies to derive the real energy spectrum. Two unfolding algorithms are implemented and studied, and response matrices are modeled for four different composition assumptions. With each assumption, energy spectra are unfolded for three different bins in inclination, using a data sample with an exposure of 3.86.10{sup 11} m{sup 2} s sr, taken in August 2007. The range of the spectrum is 1-80 PeV. Finally, a new analysis method is developed that uses the fact that cosmic rays in the PeV range are expected to be isotropic. It is shown that this requirement can be used for a likelihood estimation that is sensitive to composition without using additional information from other detector components. The analysis shows a clear preference of

  20. Fingerprinting El Nino Southern Ocean events using oxygen triple isotopic composition of aerosol sulfate from the South Pole snow pit samples

    Science.gov (United States)

    Thiemens, M. H.; Abaunza Quintero, M. M.; Shaheen, R.; Jackson, T. L.; McCabe, J.; Savarino, J. P.

    2011-12-01

    According to the Intergovernmental Panel on Climate Change 4th assessment report [IPCC 2007], aerosols are the largest source of uncertainty in modeling the earth's radiative budget. Sulfate aerosols contributes to global cooling that may mask warming effect by greenhouse gases, therefore, high resolution record of aerosol sulfate can help to understand the impact of anthropogenic activities and natural variations on climate change. Sulfate aerosols were extracted from the ice pit samples obtained from the South Pole (1979-2002) at a high resolution temporal record of the winter and summer seasons. To insure highest measurement ability of very small samples (few nano moles) a hydrogen peroxide cleaning method was developed to remove organic impurities from aerosols which otherwise significantly affect O-triple isotopic measurement of the sulfates. Preliminary data indicated non sea salt contributions of 70-95% with a range in δ18OVSMOW = -1.86 -12% and Δ17O = 0.8-3.7% for the years 1990-2001. The positive Δ17O of sulfate derives from aqueous phase oxidation of SO2 by H2O2 and O3 and involves transfer of the isotopic anomaly from the oxidant to the product sulfate. All other sulfate sources (sea salt sulfates and primary sulfates from fossil fuel combustion), including gas-phase oxidation by OH in the troposphere, metal catalyzed oxidation of S(IV) to S(VI), are strictly mass dependent (Δ17O = 0%). The magnitude of the transfer of the Δ17O varies according to the relative contribution from H2O2 at pH 6 (Δ17O = 8%). Seasonal variations of these oxidants and their contribution to S(IV) oxidation will be discussed. Since our samples include the time period 1977-2002, each year divided into two parts (winter and summer season's aerosols), in addition to seasonal variation in sulfate oxidation pathways, we may also be able to assess if the oxidation cycle of sulfate changes during El Niño years.

  1. Lunar Reconnaissance Orbiter Camera Observations Relating to Science and Landing Site Selection in South Pole-Aitken Basin for a Robotic Sample Return Mission

    Science.gov (United States)

    Jolliff, B. L.; Clegg-Watkins, R. N.; Petro, N. E.; Lawrence, S. L.

    2016-01-01

    The Moon's South Pole-Aitken basin (SPA) is a high priority target for Solar System exploration, and sample return from SPA is a specific objective in NASA's New Frontiers program. Samples returned from SPA will improve our understanding of early lunar and Solar System events, mainly by placing firm timing constraints on SPA formation and the post-SPA late-heavy bombardment (LHB). Lunar Reconnaissance Orbiter Camera (LROC) images and topographic data, especially Narrow Angle Camera (NAC) scale (1-3 mpp) morphology and digital terrain model (DTM) data are critical for selecting landing sites and assessing landing hazards. Rock components in regolith at a given landing site should include (1) original SPA impact-melt rocks and breccia (to determine the age of the impact event and what materials were incorporated into the melt); (2) impact-melt rocks and breccia from large craters and basins (other than SPA) that represent the post-SPA LHB interval; (3) volcanic basalts derived from the sub-SPA mantle; and (4) older, "cryptomare" (ancient buried volcanics excavated by impact craters, to determine the volcanic history of SPA basin). All of these rock types are sought for sample return. The ancient SPA-derived impact-melt rocks and later-formed melt rocks are needed to determine chronology, and thus address questions of early Solar System dynamics, lunar history, and effects of giant impacts. Surface compositions from remote sensing are consistent with mixtures of SPA impactite and volcanic materials, and near infrared spectral data distinguish areas with variable volcanic contents vs. excavated SPA substrate. Estimating proportions of these rock types in the regolith requires knowledge of the surface deposits, evaluated via morphology, slopes, and terrain ruggedness. These data allow determination of mare-cryptomare-nonmare deposit interfaces in combination with compositional and mineralogical remote sensing to establish the types and relative proportions of materials

  2. Relativistic Celestial Mechanics of the Solar System

    CERN Document Server

    Kopeikin, Sergei; Kaplan, George

    2011-01-01

    This authoritative book presents the theoretical development of gravitational physics as it applies to the dynamics of celestial bodies and the analysis of precise astronomical observations. In so doing, it fills the need for a textbook that teaches modern dynamical astronomy with a strong emphasis on the relativistic aspects of the subject produced by the curved geometry of four-dimensional spacetime. The first three chapters review the fundamental principles of celestial mechanics and of special and general relativity. This background material forms the basis for understanding relativistic r

  3. The Celestial Vault: The Magic of Astrology

    Science.gov (United States)

    McGaha, J.

    2004-11-01

    Astrology is a "Geocentric System" that supports the "Astrological Principle". This principle, that human beings and their actions are influenced by the positions of celestial objects, is not objectively supported. The "planetary gods" found in the heavens provided order to help explain the chaotic events in life on earth. Is this why many people think their horoscopes are correct, with the "stars" taking credit? Do "celestial movements" foretell the future? What is the evidence for Astrology? The historical, psychological and physical foundations of astrology will be discussed.

  4. Observations of the azimuthal dependence of normal mode coupling below 4 mHz at the South Pole and its nearby stations: Insights into the anisotropy beneath the Transantarctic Mountains

    Science.gov (United States)

    Hu, Xiao Gang

    2016-08-01

    Normal mode coupling pair 0S26-0T26 and 0S27-0T27 are significantly present at the South Pole station QSPA after the 2011/03/11 Mw9.1 Tohoku earthquake. In an attempt to determine the mechanisms responsible for the coupling pairs, I first investigate mode observations at 43 stations distributed along the polar great-circle path for the earthquake and observations at 32 Antarctic stations. I rule out the effect of Earth's rotation as well as the effect of global large-scale lateral heterogeneity, but argue instead for the effect of small-scale local azimuthal anisotropy in a depth extent about 300 km. The presence of quasi-Love waveform in 2-5 mHz at QSPA and its nearby stations confirms the predication. Secondly, I analyze normal mode observations at the South Pole location after 28 large earthquakes from 1998 to 2015. The result indicates that the presence of the mode coupling is azimuthal dependent, which is related to event azimuths in -46° to -18°. I also make a comparison between the shear-wave splitting measurements of previous studies and the mode coupling observations of this study, suggesting that their difference can be explained by a case that the anisotropy responsible for the mode coupling is not just below the South Pole location but located below region close to the Transantarctic Mountains (TAM). Furthermore, more signals of local azimuthal anisotropy in normal-mode observations at QSPA and SBA, such as coupling of 0S12-0T11 and vertical polarization anomaly for 0T10, confirms the existence of deep anisotropy close to TAM, which may be caused by asthenospheric mantle flow and edge convection around cratonic keel of TAM.

  5. The Accuracy of Praziquantel Dose Poles for Mass Treatment of Schistosomiasis in School Girls in KwaZulu-Natal, South Africa

    DEFF Research Database (Denmark)

    Baan, Marije; Galappaththi-Arachchige, Hashini Nilushika; Gagai, Silindile;

    2016-01-01

    Background More than 260 million people live with schistosomiasis and regular mass-treatment should be implemented to prevent morbidity. Praziquantel, dosed at 40 milligrams per kilogram bodyweight, is the drug of choice. During the last decades the WHO Tablet Pole-which estimates tablet need...... Pole were used to indicate the amount of praziquantel according to height and the dose in milligrams per kilogram bodyweight was calculated. The BMI correction was performed by adding 600 milligrams (1 tablet) to the indicated dose if a person was overweight/obese. Principal Findings 3157 female...

  6. The North Pole Environmental Observatory

    Science.gov (United States)

    Morison, J.; Aagaard, K.; Falkner, K.; Heiberg, A.; McPhee, M.; Moritz, D.; Overland, J.; Perovich, D.; Richter-Menge, J.; Shimada, K.; Steele, M.; Takizawa, T.; Woodgate, R.

    2001-12-01

    The Arctic environment is changing. The North Pole Environmental Observatory (NPEO) was established as a type of program of long-term observations required to understand Arctic change. The North Pole region was chosen because it is central to observed changes, there is a reasonable past history of measurements, and there is often a large gap there in the coverage of surface measurements. NPEO has three main components, (1) an automated drifting station composed of several buoys to measure atmospheric, upper ocean, and ice variables, (2) a sub-surface mooring at the Pole measuring ocean properties and ice draft, and (3) an airborne hydrographic survey that provides a snapshot spatial description of upper ocean properties. The first observatory was established at the Pole in April 2000 by aircraft flying out of Alert. The drifting station portion consisted of ocean ice and meteorological buoys. Over one year the drifting station passed south through Fram Strait and stopped operating in the Greenland Sea. The airborne hydrographic survey made 6 stations between Alert, the Pole, and beyond. The sub-surface mooring was not deployed. In 2001 the drifting station was similar, but the operation was expanded to deploy a 4000-m mooring at the Pole. The mooring includes current meters, C-T sensors, ADCP, and an ice draft-profiling sonar. It will be recovered in 2002. The hydrographic survey covered a new line from the Pole to 85N, 170W. The 2000 hydrographic survey showed that the changes characterizing the Pole region in the 1990s persist, but with some deepening and some slight retreat toward climatology. The section from Alert shows that upper ocean conditions near the coast have become much like the Western Arctic with low mixed layer salinity and a secondary shallow temperature maximum. The observations indicate a general counterclockwise shift in water mass locations. Among other things, the NPEO 2000 drifting station data indicate the cold halocline is still thinner

  7. Poling of Planar Silica Waveguides

    DEFF Research Database (Denmark)

    Arentoft, Jesper; Kristensen, Martin; Jensen, Jesper Bo

    1999-01-01

    UV-written planar silica waveguides are poled using two different poling techniques, thermal poling and UV-poling. Thermal poling induces an electro-optic coefficient of 0.067 pm/V. We also demonstrate simultaneous UV-writing and UV-poling. The induced electro-optic effect shows a linear dependence...

  8. Celestial Ephemerides in an Expanding Universe

    CERN Document Server

    Kopeikin, Sergei

    2012-01-01

    Post-Newtonian theory was instrumental in conducting the critical experimental tests of general relativity and in building the astronomical ephemerides of celestial bodies in the solar system with an unparalleled precision. The cornerstone of the theory is the postulate that the solar system is gravitationally isolated from the rest of the universe and the background spacetime is asymptotically flat. The present article extends this theoretical concept and formulates the principles of celestial dynamics of particles and light moving in gravitational field of a localized astronomical system embedded to the expanding Friedmann-Lemaitre-Robertson-Walker (FLRW) universe. We formulate the precise mathematical concept of the Newtonian limit of Einstein's field equations in the conformally-flat FLRW spacetime and analyze the geodesic motion of massive particles and light in this limit. We prove that by doing conformal spacetime transformations, one can reduce the equations of motion of particles and light to the cla...

  9. Recent advances in celestial and space mechanics

    CERN Document Server

    Chyba, Monique

    2016-01-01

    This book presents recent advances in space and celestial mechanics, with a focus on the N-body problem and astrodynamics, and explores the development and application of computational techniques in both areas. It highlights the design of space transfers with various modes of propulsion, like solar sailing and low-thrust transfers between libration point orbits, as well as a broad range of targets and applications, like rendezvous with near Earth objects. Additionally, it includes contributions on the non-integrability properties of the collinear three- and four-body problem, and on general conditions for the existence of stable, minimum energy configurations in the full N-body problem. A valuable resource for physicists and mathematicians with research interests in celestial mechanics, astrodynamics and optimal control as applied to space transfers, as well as for professionals and companies in the industry.

  10. GAOUA realizations of the Celestial Reference Frame

    Science.gov (United States)

    Yatskiv, Ya.; Bolotin, S.; Kur'yanova, A.

    2005-09-01

    Short overview of the activity of the Main Astronomical observatory of National Academy of Science of Ukraine for maintenance and extension of the International Celestial Reference Frame (ICRF) is presented. Special attention is paid on the time stabilities of positions of radio sources (RS) and on the selection of a subset of RS to be used for maintenance of the ICRF. It is shown that seven RS qualified by the IERS as defining sources are unstable.

  11. Celestial Fireworks from Dying Stars

    Science.gov (United States)

    2011-04-01

    This image of the nebula NGC 3582, which was captured by the Wide Field Imager on the MPG/ESO 2.2-metre telescope at ESO's La Silla Observatory in Chile, shows giant loops of gas bearing a striking resemblance to solar prominences. These loops are thought to have been ejected by dying stars, but new stars are also being born within this stellar nursery. These energetic youngsters emit intense ultraviolet radiation that makes the gas in the nebula glow, producing the fiery display shown here. NGC 3582 is part of a large star-forming region in the Milky Way, called RCW 57. It lies close to the central plane of the Milky Way in the southern constellation of Carina (The Keel of Jason's ship, the Argo). John Herschel first saw this complex region of glowing gas and dark dust clouds in 1834, during his stay in South Africa. Some of the stars forming in regions like NGC 3582 are much heavier than the Sun. These monster stars emit energy at prodigious rates and have very short lives that end in explosions as supernovae. The material ejected from these dramatic events creates bubbles in the surrounding gas and dust. This is the probable cause of the loops visible in this picture. This image was taken through multiple filters. From the Wide Field Imager, data taken through a red filter are shown in green and red, and data taken through a filter that isolates the red glow characteristic of hydrogen are also shown in red. Additional infrared data from the Digitized Sky Survey are shown in blue. The image was processed by ESO using the observational data identified by Joe DePasquale, from the United States [1], who participated in ESO's Hidden Treasures 2010 astrophotography competition [2]. The competition was organised by ESO in October-November 2010, for everyone who enjoys making beautiful images of the night sky using astronomical data obtained using professional telescopes. Notes [1] Joe searched through ESO's archive and identified datasets that he used to compose his

  12. Research career of an astronomer who has studied celestial mechanics

    Science.gov (United States)

    Kozai, Yoshihide

    2016-09-01

    Celestial mechanics has been a classical field of astronomy. Only a few astronomers were in this field and not so many papers on this subject had been published during the first half of the 20th century. However, as the beauty of classical dynamics and celestial mechanics attracted me very much, I decided to take celestial mechanics as my research subject and entered university, where a very famous professor of celestial mechanics was a member of the faculty. Then as artificial satellites were launched starting from October 1958, new topics were investigated in the field of celestial mechanics. Moreover, planetary rings, asteroids with moderate values of eccentricity, inclination and so on have become new fields of celestial mechanics. In fact I have tried to solve such problems in an analytical way. Finally, to understand what gravitation is I joined the TAMA300 gravitational wave detector group.

  13. Gravitation and celestial mechanics investigations with Galileo

    Science.gov (United States)

    Anderson, J. D.; Armstrong, J. W.; Campbell, J. K.; Estabrook, F. B.; Krisher, T. P.; Lau, E. L.

    1992-01-01

    The gravitation and celestial mechanics investigations that are to be conducted during the cruise and Orbiter phases of the Galileo Mission cover four investigation categories: (1) the gravity fields of Jupiter and its four major satellites; (2) a search for gravitational radiation; (3) mathematical modeling of general relativistic effects on Doppler ranging data; and (4) improvements of the Jupiter ephemeris via Orbiter ranging. Also noted are two secondary objectives, involving a range fix during Venus flyby and the determination of the earth's mass on the bases of the two earth gravity assists used by the mission.

  14. Initial deep LOFAR observations of epoch of reionization windows. I. The north celestial pole

    NARCIS (Netherlands)

    S. Yatawatta; . et al.; J.W.T. Hessels; J. van Leeuwen; M. Wise

    2013-01-01

    Aims. The aim of the LOFAR epoch of reionization (EoR) project is to detect the spectral fluctuations of the redshifted HI 21 cm signal. This signal is weaker by several orders of magnitude than the astrophysical foreground signals and hence, in order to achieve this, very long integrations, accurat

  15. Initial deep LOFAR observations of epoch of reionization windows: I. The north celestial pole

    NARCIS (Netherlands)

    Yatawatta, S.; Bruyn, de A.G.; Brentjens, M.A.; Labropoulos, P.; Pandey, V.N.; Kazemi, S.; Zaroubi, S.; Koopmans, L.V.E.; Offringa, A.R.; Jelic, V.; Martinez Rubi, O.; Veligatla, V.; Wijnholds, S.J.; Brouw, W.N.; Bernardi, G.; Ciardi, B.; Daiboo, S.; Harker, G.; Mellema, G.; Schaye, J.; Thomas, R.; Vedantham, H.; Chapman, E.; Abdalla, F.B.; Alexov, A.; Anderson, J.; Avruch, I.M.; Batejat, F.; Bell, M.E.; Bell, M.R.; Bentum, M.J.; Best, P.; Bonafede, A.; Bregman, J.; Breitling, F.; Brink, van de R.H.; Broderick, J.W.; Brüggen, M.; Conway, J.; Gasperin, de F.; Geus, de E.; Duscha, S.; Falcke, H.; Fallows, R.A.; Ferrari, C.; Frieswijk, W.; Garrett, M.A.; Griessmeier, J.M.; Gunst, A.W.; Hassall, T.E.; Hessels, J.W.T.; Hoeft, M.; Iacobelli, M.; Juette, E.; Karastergiou, A.; Kondratiev, V.I.; Kramer, M.; Kuniyoshi, M.; Kuper, G.; Leeuwen, van J.; Maat, P.; Mann, G.; McKean, J.P.; Mevius, M.; Mol, J.D.; Munk, H.; Nijboer, R.; Noordam, J.E.; Norden, M.J.; Orrú, E.; Paas, H.; Pandey-Pommier, M.; Pizzo, R.; Polatidis, A.G.; Reich, W.; Röttgering, H.J.A.; Sluman, J.; Smirnov, O.; Stappers, B.; Steinmetz, M.; Tagger, M.; Tang, Y.; Tasse, C.; Veen, ter S.; Vermeulen, R.; Weeren, van R.J.; Wise, M.; Wucknitz, O.; Zarka, P.

    2013-01-01

    The aim of the LOFAR Epoch of Reionization (EoR) project is to detect the spectral fluctuations of the redshifted HI 21cm signal. This signal is weaker by several orders of magnitude than the astrophysical foreground signals and hence, in order to achieve this, very long integrations, accurate calib

  16. Initial deep LOFAR observations of epoch of reionization windows : I. The north celestial pole

    NARCIS (Netherlands)

    Yatawatta, S.; de Bruyn, A. G.; Brentjens, M. A.; Labropoulos, P.; Pandey, V. N.; Kazemi, S.; Zaroubi, S.; Koopmans, L. V. E.; Offringa, A. R.; Jelic, V.; Rubi, O. Martinez; Veligatla, V.; Wijnholds, S. J.; Brouw, W. N.; Bernardi, G.; Ciardi, B.; Daiboo, S.; Harker, G.; Schaye, J.; Thomas, R.; Vedantham, H.; Chapman, E.; Abdalla, F. B.; Alexov, A.; Anderson, J.; Avruch, I. M.; Batejat, F.; Bell, M. E.; Bell, M. R.; Bentum, M.; Best, P.; Bonafede, A.; Bregman, J.; Breitling, F.; van de Brink, R. H.; Broderick, J. W.; Brueggen, M.; Conway, J.; de Gasperin, F.; de Geus, E.; Duscha, S.; Falcke, H.; Fallows, R. A.; Ferrari, C.; Frieswijk, W.; Garrett, M. A.; Griessmeier, J. M.; Gunst, A. W.; Hassall, T. E.; Hessels, J. W. T.; Hoeft, M.; Iacobelli, M.; Juette, E.; Karastergiou, A.; Kondratiev, V. I.; Kramer, M.; Kuniyoshi, M.; Kuper, G.; van Leeuwen, J.; Maat, P.; Mann, G.; McKean, J. P.; Mevius, M.; Mol, J.D.; Munk, H.; Nijboer, R.; Noordam, J. E.; Norden, M. J.; Orru, E.; Paas, H.; Pandey-Pommier, M.; Pizzo, R.; Polatidis, A. G.; Reich, W.; Rottgering, H. J. A.; Sluman, J.; Smirnov, O.; Stappers, B.; Steinmetz, M.; Tagger, M.; Tang, Y.; Tasse, C.; ter Veen, S.; Vermeulen, R.; van Weeren, R. J.; Wise, M.; Wucknitz, O.; Zarka, P.; Mellema, G.

    2013-01-01

    Aims. The aim of the LOFAR epoch of reionization (EoR) project is to detect the spectral fluctuations of the redshifted HI 21 cm signal. This signal is weaker by several orders of magnitude than the astrophysical foreground signals and hence, in order to achieve this, very long integrations, accurat

  17. North pole, South pole the quest to understand Earth's magnetism

    CERN Document Server

    Turner, Gillian

    2010-01-01

    Going all the way back to the Roman legend of a shepherd whose iron-studded boots stuck to the rocks, this book charts the history of the earth's magnetism, which intrigued and stumped scientists and ordinary people for centuries. Absorbing and accessible, it is a lively study of what exactly magnetic force is, what causes it, and what its place has been throughout scientific history, offering detailed insights into the inner workings of the planet and its magnetic shield.

  18. Trajectory and Spacecraft Design for a Pole-Sitter Mission

    OpenAIRE

    Ceriotti, Matteo; Heiligers, Jeannette; McInnes, Colin R.

    2014-01-01

    This paper provides a detailed mission analysis and systems design of a pole-sitter mission. It considers a spacecraft that is continuously above either the North or South Pole and, as such, can provide real-time, continuous, and hemispherical coverage of the polar regions. Two different propulsion strategies are proposed, which result in a near-term pole-sitter mission using solar-electric propulsion and a far-term pole-sitter mission, in which the electric thruster is hybridized with a sola...

  19. Epithermal Neutron Observations and Lunar South Pole Targeting for LCROSS Impact Planning using the Lunar Reconnaissance Orbiter (LRO), Lunar Exploring Neutron Detector (LEND)

    Science.gov (United States)

    McClanahan, T. P.; Mitrofanov, I.; Boynton, W. V.; Chin, G.; Colaprete, A.; Evans, L. G.; Garvin, J.; Harshman, K.; Litvak, R.; Malakhov, A.; Milikh, G. M.; Nandikotkur, G.; Sagdeev, R.; Sanin, A. B.; Smith, D. E.; Starr, R. D.; Trombka, J.

    2009-01-01

    LCROSS impact targeting and planning efforts included quantifying South Polar epithermal neutron flux depressions in early LEND mapped results to maximize the expected plume Hydrogen (H) yield. Epithermal neutron surface fluxes are a key geochemical indicator of surface Hydrogen (H) concentration inferred to be elevated in polar permanent shadow regions (PSR). LCROSS impact target regions were delineated as (PSR) using illumination modeling of polar topography. To quantify targets potential yield for LCROSS, LEND epithermal neutron flux observations were integrated over LCROSS targets of interest and compared to background observations. Discussion will define methods review impact prior estimates and contrast post impact results.

  20. A Snapshot-Based Mechanism for Celestial Orientation.

    Science.gov (United States)

    El Jundi, Basil; Foster, James J; Khaldy, Lana; Byrne, Marcus J; Dacke, Marie; Baird, Emily

    2016-06-01

    In order to protect their food from competitors, ball-rolling dung beetles detach a piece of dung from a pile, shape it into a ball, and roll it away along a straight path [1]. They appear to rely exclusively on celestial compass cues to maintain their bearing [2-8], but the mechanism that enables them to use these cues for orientation remains unknown. Here, we describe the orientation strategy that allows dung beetles to use celestial cues in a dynamic fashion. We tested the underlying orientation mechanism by presenting beetles with a combination of simulated celestial cues (sun, polarized light, and spectral cues). We show that these animals do not rely on an innate prediction of the natural geographical relationship between celestial cues, as other navigating insects seem to [9, 10]. Instead, they appear to form an internal representation of the prevailing celestial scene, a "celestial snapshot," even if that scene represents a physical impossibility for the real sky. We also find that the beetles are able to maintain their bearing with respect to the presented cues only if the cues are visible when the snapshot is taken. This happens during the "dance," a behavior in which the beetle climbs on top of its ball and rotates about its vertical axis [11]. This strategy for reading celestial signals is a simple but efficient mechanism for straight-line orientation. PMID:27185557

  1. Celestial Mechanics: from the bases of the past to the challenges of the future

    Science.gov (United States)

    de Melo, C. F.; Prado, A. F. B. A.; Macau, E. E. N.; Winter, O. C.; Gomes, V. M.

    2015-10-01

    This special issue of Journal of Physics: Conference Series brings a set of 31 papers presented in the Brazilian Colloquium on Orbital Dynamics (CBDO), held on December 1 - 5, 2014, in the city of Águas de Lindoia, Brazil. CBDO is a traditional and important scientific meeting in the areas of Theoretical and Applied Celestial Mechanics. The meeting takes place every two years, when researchers from South America and also guests from other continents present their works and discuss the paths trodden by the space sciences.

  2. The stratification of regolith on celestial objects

    CERN Document Server

    Schräpler, Rainer; von Borstel, Ingo; Güttler, Carsten

    2015-01-01

    All atmosphere-less planetary bodies are covered with a dust layer, the so-called regolith, which determines the optical, mechanical and thermal properties of their surface. These properties depend on the regolith material, the size distribution of the particles it consists of, and the porosity to which these particles are packed. We performed experiments in parabolic flights to determine the gravity dependency of the packing density of regolith for solid-particle sizes of 60 $\\mu$m and 1 mm as well as for 100-250 $\\mu$m-sized agglomerates of 1.5 $\\mu$m-sized solid grains. We utilized g-levels between 0.7 m s$^{-2}$ and 18 m s$^{-2}$ and completed our measurements with experiments under normal gravity conditions. Based on previous experimental and theoretical literature and supported by our new experiments, we developed an analytical model to calculate the regolith stratification of celestial rocky and icy bodies and estimated the mechanical yields of the regolith under the weight of an astronaut and a spacec...

  3. Celestial shadows eclipses, transits, and occultations

    CERN Document Server

    Westfall, John

    2015-01-01

    Much of what is known about the universe comes from the study of celestial shadows—eclipses, transits, and occultations.  The most dramatic are total eclipses of the Sun, which constitute one of the most dramatic and awe-inspiring events of nature.  Though once a source of consternation or dread, solar eclipses now lead thousands of amateur astronomers and eclipse-chasers to travel to remote points on the globe to savor their beauty and the adrenaline-rush of experiencing totality, and were long the only source of information about the hauntingly beautiful chromosphere and corona of the Sun.   Long before Columbus, the curved shadow of the Earth on the Moon during a lunar eclipse revealed that we inhabit a round world. The rare and wonderful transits of Venus, which occur as it passes between the Earth and the Sun, inspired eighteenth century expeditions to measure the distance from the Earth to the Sun, while the recent transits of 2004 and 2012 were the most widely observed ever--and still produced re...

  4. Relativistic Celestial Mechanics of the Solar System

    Science.gov (United States)

    Kopeikin, Sergei; Efroimsky, Michael; Kaplan, George

    2011-09-01

    The general theory of relativity was developed by Einstein a century ago. Since then, it has become the standard theory of gravity, especially important to the fields of fundamental astronomy, astrophysics, cosmology, and experimental gravitational physics. Today, the application of general relativity is also essential for many practical purposes involving astrometry, navigation, geodesy, and time synchronization. Numerous experiments have successfully tested general relativity to a remarkable level of precision. Exploring relativistic gravity in the solar system now involves a variety of high-accuracy techniques, for example, very long baseline radio interferometry, pulsar timing, spacecraft Doppler tracking, planetary radio ranging, lunar laser ranging, the global positioning system (GPS), torsion balances and atomic clocks. Over the last few decades, various groups within the International Astronomical Union have been active in exploring the application of the general theory of relativity to the modeling and interpretation of high-accuracy astronomical observations in the solar system and beyond. A Working Group on Relativity in Celestial Mechanics and Astrometry was formed in 1994 to define and implement a relativistic theory of reference frames and time scales. This task was successfully completed with the adoption of a series of resolutions on astronomical reference systems, time scales, and Earth rotation models by the 24th General Assembly of the IAU, held in Manchester, UK, in 2000. However, these resolutions only form a framework for the practical application of relativity theory, and there have been continuing questions on the details of the proper application of relativity theory to many common astronomical problems. To ensure that these questions are properly addressed, the 26th General Assembly of the IAU, held in Prague in August 2006, established the IAU Commission 52, "Relativity in Fundamental Astronomy". The general scientific goals of the new

  5. Industrial Scale Production of Celestial Body Simulants Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The technical objectives of this program are to develop a cost-effective process to deliver Celestial body simulants for the foreseeable future. Specifically, the...

  6. A Review of Celestial Burying Ground in Tibet

    Institute of Scientific and Technical Information of China (English)

    YUQIAN

    2005-01-01

    Celestial burying ground ,also called “Mandala”,is where life leaves and comes.A huge piece of stone hidden in high mountains is surrounded by burning plants that give up smoke going up into the air.

  7. Physical state and temporal evolution of icy surfaces in the Mars South Pole by retrieving their bidirectional reflectance from CRISM observations

    Science.gov (United States)

    Douté, Sylvain Michel; Pilorget, Cedric; Fernando, Jennifer

    2016-10-01

    On Mars H2O and CO2 ices can be found as seasonal or perennial deposits notably in the polar regions. At the moment little is known about their bidirectional reflectance factor (BRF) despite the significance of such information for characterizing the composition, physical state and energy balance of the icy surfaces from the bolometric albedo. The BRF is potentially accessible thanks to the near-simultaneous multi-angle, hyperspectral observations of the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) implying 11 viewing angles in visible and infrared ranges. However, its extraction from the CRISM measurements is especially challenging. Indeed, the atmospheric aerosols (mineral dust, sometimes H2O ice) have a strong contribution in the CRISM measurements that must be corrected. At high latitudes, their contribution is accentuated because the sun is low above the horizon. Besides, the BRF of ices is expected to be highly anisotropic especially under grazing illumination creating difficulties with the traditional Lambertian surface assumption commonly used for atmospheric correction. In previous research we put forward the Multi-angle Approach for Retrieval of Surface Reflectance from CRISM Observations (MARS-ReCO), an algorithm that characterizes and corrects the aerosol scattering effects. The aerosol optical depth (AOD) and the BRF of surface materials are retrieved conjointly and coherently as a function of wavelength. In this work, we apply MARS-ReCO on time series of CRISM sequences over different regions of interest in the outskirts of the south permanent polar cap. The time series span from mid-spring to late summer during which the CO2 ice sublimates revealing H2O frost and defrosted terrains. No ground truth is available for the investigated regions but cross-validation with other datasets such as observations by OMEGA (mapping spectrometer on MEX) can be applied. Thanks to the atmospheric correction, we are able to identify various classes of

  8. Frontiers in Relativistic Celestial Mechanics, Vol. 2, Applications and Experiments

    Science.gov (United States)

    Kopeikin, Sergei

    2014-08-01

    Relativistic celestial mechanics - investigating the motion celestial bodies under the influence of general relativity - is a major tool of modern experimental gravitational physics. With a wide range of prominent authors from the field, this two-volume series consists of reviews on a multitude of advanced topics in the area of relativistic celestial mechanics - starting from more classical topics such as the regime of asymptotically-flat spacetime, light propagation and celestial ephemerides, but also including its role in cosmology and alternative theories of gravity as well as modern experiments in this area. This second volume of a two-volume series covers applications of the theory as well as experimental verifications. From tools to determine light travel times in curved space-time to laser ranging between earth and moon and between satellites, and impacts on the definition of time scales and clock comparison techniques, a variety of effects is discussed. On the occasion of his 80-th birthday, these two volumes honor V. A. Brumberg - one of the pioneers in modern relativistic celestial mechanics. Contributions include: J. Simon, A. Fienga: Victor Brumberg and the French school of analytical celestial mechanics T. Fukushima: Elliptic functions and elliptic integrals for celestial mechanics and dynamical astronomy P. Teyssandier: New tools for determining the light travel time in static, spherically symmetric spacetimes beyond the order G2 J. Müller, L. Biskupek, F. Hofmann and E. Mai: Lunar laser ranging and relativity N. Wex: Testing relativistic celestial mechanics with radio pulsars I. Ciufolini et al.: Dragging of inertial frames, fundamental physics, and satellite laser ranging G. Petit, P. Wolf, P. Delva: Atomic time, clocks, and clock comparisons in relativistic spacetime: a review

  9. Reconstruction of the celestial globe of the Ming Dynasty.

    Science.gov (United States)

    Xu, Zhengtao; Ling, Rongfu

    1997-09-01

    Four big bronze instruments were made in the seventh year of the Zhengtong reign of the Ming Dynasty (AD 1442). They are the Armillary Sphere, Abridged Armilla, Gnomon and Celestial Globe. The first three ones are well presented in the Purple Mountain Observatory. But the Celestial Globe was destroyed in the early period of the Qing Dynasty. According to the astronomical treatises of the Yuan and Ming Dynasty and related references the authors reconstructed this instrument in original size.

  10. Pole to Pole Videoconferences Connect Students and Scientists

    Science.gov (United States)

    Sparrow, E. B.; Lemone, P.; Yule, S.; Boger, R.; Galloni, M.; Kopplin, M. R.

    2008-12-01

    Alaskan and Argentinean students as well as arctic and antarctic scientists participated in two International Polar Year (IPY) Pole to Pole Videoconferences in 2007 and 2008. The videoconferences involved elementary, middle and high school students as well as scientists from Alaska, Argentina, Colorado and Washington DC. Alaska students were located in Fairbanks, Healy, Shageluk and Wasilla while the Argentinean students were located in Ushuaia, Argentina, at the southern tip of South America. The purpose was to ask each other and the scientists about local environmental changes, seasonal indicators, and climate change, and how to study the seasonal indicators to determine whether they are being affected by climate change. The videoconferences were followed by web chats and web forums to allow more students in other countries including those in non-polar regions, to interact with scientists, and help students develop ideas for their research projects. These activities are part of the Seasons and Biomes Project that engages K-12 teachers and students in Earth system science investigations as a way of teaching and learning science. This project also provides professional development workshops to teachers and teacher trainers. Seasons and Biomes is one of the projects in the University of the Arctic IPY Higher Education Outreach Cluster Project that has been approved by the IPY Joint Committee. As well, it is part of the GLOBE program, an international hands-on, inquiry-based Earth and environmental science and education program for primary and secondary students in 110 countries. The videoconferences, web chats and forums generated much interest and enthusiasm among students and scientists, and have provided the impetus for student research project initiations and collaborations between schools.

  11. ASTEP South: a first photometric analysis

    CERN Document Server

    Crouzet, N; Mékarnia, D; Szulágyi, J; Abe, L; Agabi, A; Fanteï-Caujolle, Y; Gonçalves, I; Barbieri, M; Schmider, F -X; Rivet, J -P; Bondoux, E; Challita, Z; Pouzenc, C; Fressin, F; Valbousquet, F; Blazit, A; Bonhomme, S; Daban, J -B; Gouvret, C; Bayliss, D; Zhou, G

    2012-01-01

    The ASTEP project aims at detecting and characterizing transiting planets from Dome C, Antarctica, and qualifying this site for photometry in the visible. The first phase of the project, ASTEP South, is a fixed 10 cm diameter instrument pointing continuously towards the celestial South pole. Observations were made almost continuously during 4 winters, from 2008 to 2011. The point-to-point RMS of 1-day photometric lightcurves can be explained by a combination of expected statistical noises, dominated by the photon noise up to magnitude 14. This RMS is large, from 2.5 mmag at R=8 to 6% at R=14, because of the small size of ASTEP South and the short exposure time (30 s). Statistical noises should be considerably reduced using the large amount of collected data. A 9.9-day period eclipsing binary is detected, with a magnitude R=9.85. The 2-season lightcurve folded in phase and binned into 1000 points has a RMS of 1.09 mmag, for an expected photon noise of 0.29 mmag. The use of the 4 seasons of data with a better d...

  12. Constraining gluon poles

    Directory of Open Access Journals (Sweden)

    I.V. Anikin

    2015-12-01

    Full Text Available In this letter, we revise the QED gauge invariance for the hadron tensor of Drell–Yan type processes with the transversely polarized hadron. We perform our analysis within the Feynman gauge for gluons and make a comparison with the results obtained within the light-cone gauge. We demonstrate that QED gauge invariance leads, first, to the need of a non-standard diagram and, second, to the absence of gluon poles in the correlators 〈ψ¯γ⊥A+ψ〉 related traditionally to dT(x,x/dx. As a result, these terms disappear from the final QED gauge invariant hadron tensor. We also verify the absence of such poles by analyzing the corresponding light-cone Dirac algebra.

  13. Control of subterranean termites (Isoptera: Rhinotermitidae) infesting power poles.

    Science.gov (United States)

    Horwood, Martin A; Westlake, Terry; Kathuria, Amrit

    2010-12-01

    A trial was conducted to determine the efficacy of termiticidal dusts (arsenic trioxide, triflumuron, and Metarhizium anisopliae), a timber fumigant (dazomet) and liquid termiticides (bifenthrin, chlorfenapyr, chlorpyrifos, fipronil, and imidacloprid) for controlling subterranean termites (Isoptera: Rhinotermitidae) infesting in-service power poles in New South Wales, Australia. Dusts were applied to parts of the pole where termites were present. Fumigant was inserted into holes drilled into the base of the pole. Liquid termiticides were mixed with soil around the base of the pole and injected into internal voids if present. Poles were inspected for up to 5 yr, and the time taken for reinfestation to occur was recorded. Before the start of the trial, the major Australian pole owners were surveyed to obtain an estimate of the annual national cost of termite infestation to the power supply industry. The annual costs of termite treatment and replacing damaged poles were estimated at AU$2 million and AU$13 million, respectively. Infestation rates were lower for all treatments compared with controls within the first 12 mo of the study. Dazomet, arsenic trioxide, fipronil, and chlorpyrifos were the most efficacious treatments. Efficacy was positively related to the amount of termiticide applied and negatively related to the infestation severity but was unaffected by geographical location. Survival curves were calculated of the time elapsed before the recurrence of termite infestations (survival absence of reinfestation). Survival was highest for poles treated with liquid termiticides. PMID:21309237

  14. Frontiers in Relativistic Celestial Mechanics, Vol. 1. Theory

    Science.gov (United States)

    Kopeikin, Sergei

    2014-10-01

    Relativistic celestial mechanics - investigating the motion celestial bodies under the influence of general relativity - is a major tool of modern experimental gravitational physics. With a wide range of prominent authors from the field, this two-volume series consists of reviews on a multitude of advanced topics in the area of relativistic celestial mechanics - starting from more classical topics such as the regime of asymptotically-flat spacetime, light propagation and celestial ephemerides, but also including its role in cosmology and alternative theories of gravity as well as modern experiments in this area. This first volume of a two-volume series is concerned with theoretical foundations such as post-Newtonian solutions to the two-body problem, light propagation through time-dependent gravitational fields, as well as cosmological effects on the movement of bodies in the solar systems. On the occasion of his 80-th birthday, these two volumes honor V. A. Brumberg - one of the pioneers in modern relativistic celestial mechanics. Contributions include: M. Soffel: On the DSX-framework T. Damour: The general relativistic two body problem G. Schaefer: Hamiltonian dynamics of spinning compact binaries through high post-Newtonian approximations A. Petrov and S. Kopeikin: Post-Newtonian approximations in cosmology T. Futamase: On the backreaction problem in cosmology Y. Xie and S. Kopeikin: Covariant theory of the post-Newtonian equations of motion of extended bodies S. Kopeikin and P. Korobkov: General relativistic theory of light propagation in multipolar gravitational fields

  15. Lunar Flashlight: Illuminating the Lunar South Pole

    Science.gov (United States)

    Hayne, P. O.; Greenhagen,, B. T.; Paige, D. A.; Camacho, J. M.; Cohen, B. A.; Sellar, G.; Reiter, J.

    2016-01-01

    Recent reflectance data from LRO instruments suggest water ice and other volatiles may be present on the surface in lunar permanentlyshadowed regions, though the detection is not yet definitive. Understanding the composition, quantity, distribution, and form of water and other volatiles associated with lunar permanently shadowed regions (PSRs) is identified as a NASA Strategic Knowledge Gap (SKG) for Human Exploration. These polar volatile deposits are also scientifically interesting, having the potential to reveal important information about the delivery of water to the Earth- Moon system.

  16. Lunar Flashlight: Illuminating the Moon's South Pole

    Science.gov (United States)

    Hayne, P. O.; Cohen, B. A.; Greenhagen, B. T.; Paige, D. A.; Camacho, J. M.; Sellar, R. G.; Reiter, J.

    2016-01-01

    Recent reflectance data from LRO instruments suggest water ice and other volatiles may be present on the surface in lunar permanently shadowed regions, though the detection is not yet definitive. Understanding the composition, quantity, distribution, and form of water and other volatiles associated with lunar permanently shadowed regions (PSRs) is identified as a NASA Strategic Knowledge Gap (SKG) for Human Exploration. These polar volatile deposits are also scientifically interesting, having the potential to reveal important information about the delivery of water to the Earth-Moon system.

  17. Drilling deep in South Pole Ice

    CERN Document Server

    Karg, Timo

    2014-01-01

    To detect the tiny flux of ultra-high energy neutrinos from active galactic nuclei or from interactions of highest energy cosmic rays with the microwave background photons needs target masses of the order of several hundred cubic kilometers. Clear Antarctic ice has been discussed as a favorable material for hybrid detection of optical, radio and acoustic signals from ultra-high energy neutrino interactions. To apply these technologies at the adequate scale hundreds of holes have to be drilled in the ice down to depths of about 2500 m to deploy the corresponding sensors. To do this on a reasonable time scale is impossible with presently available tools. Remote drilling and deployment schemes have to be developed to make such a detector design reality. After a short discussion of the status of modern hot water drilling we present here a design of an autonomous melting probe, tested 50 years ago to reach a depth of about 1000 m in Greenland ice. A scenario how to build such a probe today with modern technologies...

  18. Wood pole overhead lines

    CERN Document Server

    Wareing, Brian

    2005-01-01

    This new book concentrates on the mechanical aspects of distribution wood pole lines, including live line working, environmental influences, climate change and international standards. Other topics include statutory requirements, safety, profiling, traditional and probabilistic design, weather loads, bare and covered conductors, different types of overhead systems, conductor choice, construction and maintenance. A section has also been devoted to the topic of lightning, which is one of the major sources of faults on overhead lines. The book focuses on the effects of this problem and the strate

  19. Composite poles : proving their worth

    Energy Technology Data Exchange (ETDEWEB)

    Coates, K.C.

    2009-01-15

    Electric utilities who have been evaluating the performance of composite poles have found that they have some significant advantages over wood, concrete and steel structures. Composite utility poles that were installed as pilot projects in amongst old wood pole infrastructure proved to withstand the weight of massive amounts of ice and snow buildup. The new composite poles also mitigate the negative effects of weathering, termites, woodpeckers, rusting, and cracking. While not fireproof, they are extremely fire resistant especially when coated with fire retardant. As such they are well suited for use in forested areas. They are composed of new high-strength E-glass fibres and polyurethane resins and have advanced to the ready-for-deployment stage where they can be accepted as part of a utility's replacement pole inventory. This article briefly reviewed the different hardware and installation methods that are needed to attach equipment to hollow composite poles rather than solid wood poles. Composite poles typically range from one and a half to twice the price of a comparable wood pole, but represent a savings in terms of installation, maintenance, repair, replacement and life cycle costs. They also reduce disposal costs, particularly since environmental regulations now consider treated wood poles as hazardous waste. 5 figs.

  20. Dynamical Configurations of Celestial Systems Comprised of Multiple Irregular Bodies

    CERN Document Server

    Jiang, Yu; Baoyin, Hexi; Li, Junfeng

    2016-01-01

    This manuscript considers the main features of the nonlinear dynamics of multiple irregular celestial body systems. The gravitational potential, static electric potential, and magnetic potential are considered. Based on the three established potentials, we show that three conservative values exist for this system, including a Jacobi integral. The equilibrium conditions for the system are derived and their stability analyzed. The equilibrium conditions of a celestial system comprised of n irregular bodies are reduced to 12n minus 9 equations. The dynamical results are applied to simulate the motion of multiple-asteroid systems. The simulation is useful for the study of the stability of multiple irregular celestial body systems and for the design of spacecraft orbits to triple asteroid systems discovered in the solar system. The dynamical configurations of the five triple-asteroid systems 45 Eugenia, 87 Sylvia, 93 Minerva, 216 Kleopatra, and 136617 1994CC, and the six-body system 134340 Pluto are calculated and...

  1. Dynamical configurations of celestial systems comprised of multiple irregular bodies

    Science.gov (United States)

    Jiang, Yu; Zhang, Yun; Baoyin, Hexi; Li, Junfeng

    2016-09-01

    This manuscript considers the main features of the nonlinear dynamics of multiple irregular celestial body systems. The gravitational potential, static electric potential, and magnetic potential are considered. Based on the three established potentials, we show that three conservative values exist for this system, including a Jacobi integral. The equilibrium conditions for the system are derived and their stability analyzed. The equilibrium conditions of a celestial system comprised of n irregular bodies are reduced to 12n - 9 equations. The dynamical results are applied to simulate the motion of multiple-asteroid systems. The simulation is useful for the study of the stability of multiple irregular celestial body systems and for the design of spacecraft orbits to triple-asteroid systems discovered in the solar system. The dynamical configurations of the five triple-asteroid systems 45 Eugenia, 87 Sylvia, 93 Minerva, 216 Kleopatra, and 136617 1994CC, and the six-body system 134340 Pluto are calculated and analyzed.

  2. Analysis of Sunyaev-Zel'dovich effect mass-observable relations using South Pole Telescope observations of an X-ray selected sample of low-mass galaxy clusters and groups

    Energy Technology Data Exchange (ETDEWEB)

    Liu, J.; Mohr, J.; Saro, A.; Aird, K. A.; Ashby, M. L. N.; Bautz, M.; Bayliss, M.; Benson, B. A.; Bleem, L. E.; Bocquet, S.; Brodwin, M.; Carlstrom, J. E.; Chang, C. L.; Chiu, I.; Cho, H. M.; Clocchiatti, A.; Crawford, T. M.; Crites, A. T.; de Haan, T.; Desai, S.; Dietrich, J. P.; Dobbs, M. A.; Foley, R. J.; Gangkofner, D.; George, E. M.; Gladders, M. D.; Gonzalez, A. H.; Halverson, N. W.; Hennig, C.; Hlavacek-Larrondo, J.; Holder, G. P.; Holzapfel, W. L.; Hrubes, J. D.; Jones, C.; Keisler, R.; Lee, A. T.; Leitch, E. M.; Lueker, M.; Luong-Van, D.; McDonald, M.; McMahon, J. J.; Meyer, S. S.; Mocanu, L.; Murray, S. S.; Padin, S.; Pryke, C.; Reichardt, C. L.; Rest, A.; Ruel, J.; Ruhl, J. E.; Saliwanchik, B. R.; Sayre, J. T.; Schaffer, K. K.; Shirokoff, E.; Spieler, H. G.; Stalder, B.; Staniszewski, Z.; Stark, A. A.; Story, K.;  uhada, R.; Vanderlinde, K.; Vieira, J. D.; Vikhlinin, A.; Williamson, R.; Zahn, O.; Zenteno, A.

    2015-02-25

    We use microwave observations from the South Pole Telescope (SPT) to examine the Sunyaev–Zel'dovich effect (SZE) signatures of a sample of 46 X-ray selected groups and clusters drawn from ~6 deg2 of the XMM–Newton Blanco Cosmology Survey. These systems extend to redshift z = 1.02 and probe the SZE signal to the lowest X-ray luminosities (≥1042 erg s-1) yet; these sample characteristics make this analysis complementary to previous studies. We develop an analysis tool, using X-ray luminosity as a mass proxy, to extract selection-bias-corrected constraints on the SZE significance and Y_500 mass relations. The former is in good agreement with an extrapolation of the relation obtained from high-mass clusters. However, the latter, at low masses, while in good agreement with the extrapolation from the high-mass SPT clusters, is in tension at 2.8σ with the Planck constraints, indicating the low-mass systems exhibit lower SZE signatures in the SPT data. We also present an analysis of potential sources of contamination. For the radio galaxy point source population, we find 18 of our systems have 843 MHz Sydney University Molonglo Sky Survey sources within 2 arcmin of the X-ray centre, and three of these are also detected at significance >4 by SPT. Of these three, two are associated with the group brightest cluster galaxies, and the third is likely an unassociated quasar candidate. We examine the impact of these point sources on our SZE scaling relation analyses and find no evidence of biases. We also examine the impact of dusty galaxies using constraints from the 220 GHz data. The stacked sample provides 2.8σ significant evidence of dusty galaxy flux, which would correspond to an average underestimate of the SPT Y_500 signal that is (17 ± 9)per cent in this sample of low-mass systems. Finally, we explore the impact of future data from SPTpol and XMM-XXL, showing that it will lead to a factor of 4 to 5 tighter

  3. The GAOUA series of compiled celestial reference frames

    Science.gov (United States)

    Molotaj, O.; Tel'Nyuk-Adamchuk, V.; Yatskiv, Ya.

    2000-09-01

    The GAOUA series of compiled celestial reference frames is obtained by using the original Kyiv arc length approach for combination of initial RSC solutions which are yearly submitted to the IERS CB by various VLBI Analysis Centers. The presentation is concerned with an analysis of accuracies of these individual and combined solutions and that of the ICRF.

  4. Foraminíferos bentónicos aglutinados de los Depósitos turbidíticos. Área Nápoles, Sur de San Marcos de Tarrazú, Costa Rica Agglutinated foraminifera from turbiditic deposits, Nápoles Area, South of San Marcos, Tarrazú, Costa Rica

    Directory of Open Access Journals (Sweden)

    Lolita Campos

    2012-12-01

    Full Text Available En el sector de Nápoles, San Marcos de Tarrazú, situado dentro de una ancha faja estructural aún no completamente definida en el límite entre las cuencas sedimentarias de Valle Central y Térraba, la muestra LOR-10 brindó una asociación faunística de exclusivamente foraminíferos bentónicos. Como no fueron encontrados foraminíferos planctónicos no se pudieron realizar determinaciones bioestratigráficas. Del total de individuos identificados, estos corresponden a 3 subórdenes, 9 superfamilias y 33 especies. Con respecto al índice de diversidad de Shannon (H, para interpretaciones paleoecológicas el resultado fue de H=1.4, indicando condiciones de ciénagas y ambientes marginales marinos. Los foraminíferos bentónicos identificados hasta nivel de especie en la muestra, poseen rangos de existencia muy amplio señalando una zona que se extiende del Triásico al Reciente. Desde el punto de vista paleoecológico en relación con la salinidad, fueron determinados los siguientes porcentajes 53.3% de rotaliinos, 41.9% de texturaliinos y 2.2% de miliólidos, valores que son indicadores de ambientes de laguna salobre, estuario y plataforma, esta mezcla de fauna de ambientes distintos sugiere que se trata de un depósito alóctono retrabajado. La identificación de Portatrochammina sp. (4.3% que aparece entre los 500 y 2000 m, pero es abundante aproximadamente entre los 600 y 700 m y de Cibicides lobatulus (3.2% indicadora de la zona batial media superior (500-1500 m, confirman la interpretación del ambiente del depósito como un abanico submarino de talud del ámbito batial medio. Así mismo la preeminencia de los foraminíferos aglutinados sugiere un importante aporte de detrito hacia la cuenca. Por último, las cuencas estratificadas, frías, profundas, con altas tasas de sedimentación favorecen la preservación de las asociaciones de foraminíferos aglutinados sobre los carbonatadosIn the area of Napoles, South of San Marcos, Tarraz

  5. Division a Commission 7: Celestial Mechanics and Dynamical Astronomy

    Science.gov (United States)

    Morbidelli, Alessandro; Beaugé, Cristian; Knežević, Zoran; Celetti, Alessandra; Haghighipour, Nader; Hut, Piet; Laskar, Jacques; Mikkola, Seppo; Roig, Fernando

    2016-04-01

    In order to mark a distinction with the traditional triennial reports, for this legacy issue we have asked our present and past OC members, as well as a few other outstanding members of the Celestial Mechanics community, to write a short essay on ``recent highlights and the future of Celestial Mechanics''. Below we collect the contributions of the people who responded to our invitation. As it is natural, each of them interpreted their task differently. Some produced a dissertation on broad and general aspects, others focused on a specific topic of their interest. Some considered that their role was to provide a detailed review, with a list of key references, others preferred to mention the topics for which progress has been significant but without quoting any references, implicitly considering that this progress was possible thanks to the collective efforts of many scientists, and not just a few. This is great, as we appreciate the diversity of attitudes and opinions.

  6. Paleo-Pole Positions from Martian Magnetic Anomaly Data

    Science.gov (United States)

    Frawley, James J.; Taylor, Patrick T.

    2004-01-01

    Magnetic component anomaly maps were made from five mapping cycles of the Mars Global Surveyor's magnetometer data. Our goal was to find and isolate positive and negative anomaly pairs which would indicate magnetization of a single source body. From these anomalies we could compute the direction of the magnetizing vector and subsequently the location of the magnetic pole existing at the time of magnetization. We found nine suitable anomaly pairs and from these we computed paleo-poles that were nearly equally divided between north, south and mid-latitudes. These results suggest that during the existence of the martian main magnetic field it experienced several reversals and excursions.

  7. The science of the lunar poles

    Science.gov (United States)

    Lucey, P. G.

    2011-12-01

    imaging of interiors of polar shadowed craters has been accomplished by many instruments from the ultraviolet to the radar. Imaging radars on Chandrayaan-1 and LRO have identified anomalous craters that may contain rich water ice deposits. Neutron spectrometers on Lunar Prospector and LRO directly detected hydrogen enhancements at both poles. Spectacularly, the LCROSS impact experiment detected a wide range of volatile elements and species at Cabeus crater in the lunar south polar region. While these measurements have catapulted polar science forward, much remains to be understood about the polar system, both from analysis of the current data, and new missions planned and in development. The general state of the lunar atmosphere is planned to be addressed by the UV and neutral mass spectrometers carried by the planned NASA LADEE (Lunar Atmosphere And Dust Environment Explorer) spacecraft creating an important baseline. But more data is necessary, from an in situ direct assay of polar volatiles to measurements of species and fluxes into and out of the cold traps over lengthy timescales.

  8. Elliptical Chandler pole motions of the Earth and Mars

    Science.gov (United States)

    Barkin, Yury; Ferrandiz, Jose

    2010-05-01

    In the work the values of the period and eccentricity of Chandler motion of poles of axes of rotation of the Earth and Mars have been determined. The research has been carried out on the basis of developed earlier by authors an intermediate rotary Chandler-Euler motion of the weakly deformable celestial bodies (Barkin, Ferrandiz and Getino, 1996; Barkin, 1998). An influence of a liquid core on Chandler motion of a pole in the given work has not considered. The periods of the specified pole motions make 447.1 d for the Earth and 218.1 d for Mars. In comparison with Euler motions of poles because of elastic properties of planets the Chandler periods are increased accordingly on 142.8 d (about 46.9 %) for the Earth and on 26.2 d (on 13.7 %) for Mars. Values of eccentricities of specified Chandler motions of pole e = √b2 --a2- b (here a both b are smaller and big semi-axes of Chandler ellipse) make 0.09884 for the Earth and 0.3688 for Mars (accordingly, on 21.1 % and 6.2 % more than the appropriate values of eccentricities for models of planets as rigid non-spherical bodies). Axes of an ellipse a also b correspond to the principal equatorial axes of inertia of a planet Ox and Oyfor which the moments of inertia have the smallest valueA and middle value B. The pole of the principal axis of inertia Ox for the Earth is displaced to the west on the angle 14°9285, and the pole of the principal axis of inertia Ox for Mars is displaced to the west on the angle 105°0178 (in the appropriate basic geographical systems of coordinates of the given planets). For ellipticties of Chandler trajectories ɛ = (b- a)-b the values 0.004897 (for the Earth) and 0.07048 (for Mars) have been obtained. The specified values surpass by Euler values of appropriate ellipticties on 46.8 % (in case of the Earth) and on 13.3 % (in the case of Mars). Love number k2describing the elastic properties of planets, were accepted equal 0.30 for the Earth and 0.153 for Mars. Estimations of Chandler periods

  9. Poles in the Dutch Cape Colony 1652-1814

    Directory of Open Access Journals (Sweden)

    Kowalski Mariusz

    2015-06-01

    Full Text Available The contribution of Poles to the colonisation and development of the Dutch Cape Colony is not commonly known. Yet, Poles have been appearing in this colony since its very inception (1652. During the entire period considered here the presence of Poles was the result of the strong economic ties between Poland and the Netherlands. At the end of this period there was an increase in their share, in connection with the presence of numerous alien military units on the territory of the Colony, because of Poles having served in these units. Numerous newcomers from Poland settled in South Africa for good, established families, and their progeny made up part of the local society. The evidence of this phenomenon is provided by the present-day Afrikaner families of, for instance, Drotsky, Kitshoff, Kolesky, Latsky, Masuriek, Troskie, Zowitsky, and others. A quite superficial estimation implies that the settlers coming from Poland could make up a bit over 1% of the ancestors of the present-day Afrikaners. Poles would also participate in the pioneering undertakings within the far-off fringes of the Colony, including the robbery-and-trade expedition of 1702.

  10. Calligraphic Poling for WGM Resonators

    Science.gov (United States)

    Mohageg, Makan; Strekalov, Dmitry; Savchenkov, Anatoliy; Matsko, Andrey; Ilchenko, Vladimir; Maleki, Lute

    2007-01-01

    By engineering the geometry of a nonlinear optical crystal, the effective efficiency of all nonlinear optical oscillations can be increased dramatically. Specifically, sphere and disk shaped crystal resonators have been used to demonstrate nonlinear optical oscillations at sub-milliwatt input power when cs light propagates in a Whispering Gallery Mode (WGM) of such a resonant cavity. in terms of both device production and experimentation in quantum optics, some nonlinear optical effects with naturally high efficiency can occult the desired nonlinear scattering process. the structure to the crystal resonator. In this paper, I will discuss a new method for generating poling structures in ferroelectric crystal resonators called calligraphic poling. The details of the poling apparatus, experimental results and speculation on future applications will be discussed.

  11. Stability study of realization of the celestial reference frame

    Science.gov (United States)

    Yatskiv, Ya. S.; Bolotin, S. L.; Kur'yanova, A. N.

    2004-09-01

    We present a short overview of the activity of the IERS as well as the Main Astronomical Observatory (MAO) of the National Academy of Sciences of Ukraine for maintenance and extention of the International Celestial Reference Frame (ICRF). Special attention is given to the time stabilities of positions of radio sources (RS) and to the selection of a subset of RS to be used for maintenance of the ICRF. It is shown that seven RS qualified by the IERS as defining sources are unstable.

  12. Celestial reference frame RSC (GAOUA) 98 C 01.

    Science.gov (United States)

    Molotaj, O. A.; Tel'Nyuk-Adamchuk, V. V.; Yatskiv, Ya. S.

    The celestial reference frame RSC (GAOUA) 98 C 01 was constructed by applying the Kiev arc method to five initial frames submitted to the IERS during 1997. The frame comprises positions of 631 radio sources. The frame axes are aligned to those of the ICRF with an accuracy of 0.02 mas using all 212 defining common radio sources. The internal standard errors of right ascension and declination for the defining sources are equal to 0.11 and 0.13 mas, respectively. Results of intercomparison between the ICRF, five initial frames, and the compiled frame are discussed.

  13. Kepler-16 Circumbinary System Validates Quantum Celestial Mechanics

    Directory of Open Access Journals (Sweden)

    Potter F.

    2012-01-01

    Full Text Available We report the application of quantum celestial mechanics (QCM to the Kepler-16 cir- cumbinary system which has a single planet orbiting binary stars with the important system parameters known to within one percent. Other gravitationally bound systems such as the Solar System of planets and the Jovian satellite systems have large uncertain- ties in their total angular momentum. Therefore, Kepler-16 allows us for the first time to determine whether the QCM predicted angular momentum per mass quantization is valid.

  14. Calligraphic Poling of Ferroelectric Material

    Science.gov (United States)

    Mohageg, Makan; Strekalov, Dmitry; Savchenkov, Anatoliy; Matsko, Adrey; Maleki, Lute; Iltchenko, Vladimir

    2007-01-01

    Calligraphic poling is a technique for generating an arbitrary, possibly complex pattern of localized reversal in the direction of permanent polarization in a wafer of LiNbO3 or other ferroelectric material. The technique is so named because it involves a writing process in which a sharp electrode tip is moved across a surface of the wafer to expose the wafer to a polarizing electric field in the desired pattern. The technique is implemented by use of an apparatus, denoted a calligraphic poling machine (CPM), that includes the electrode and other components as described in more detail below.

  15. The Power of Stars How Celestial Observations Have Shaped Civilization

    CERN Document Server

    Penprase, Bryan E

    2011-01-01

    What are some of the connections that bind us to the stars? How have these connections been established? And how have people all around the world and throughout time reacted to the night sky, the sun and moon, in their poetry, mythology, rituals, and temples? This book explores the influence of the sky on both ancient and modern civilization, by providing a clear overview of the many ways in which humans have used the stars as an ordering principle in their cultures, and which today still inspire us intellectually, emotionally, and spiritually. The book explores constellation lore from around the world, celestial alignments of monuments and temples, both from ancient and modern civilizations, and the role the sky has played in the cultures of the Greek, Egyptian, Babylonian, Native American, Chinese, Mayan, Aztec, and Inca. Models of the universe from each of these cultures are described clearly, and each culture’s explanation of the stars, planets, and other celestial objects are described. The roots of as...

  16. GRAIL gravity field determination using the Celestial Mechanics Approach

    Science.gov (United States)

    Arnold, Daniel; Bertone, Stefano; Jäggi, Adrian; Beutler, Gerhard; Mervart, Leos

    2015-11-01

    The NASA mission GRAIL (Gravity Recovery and Interior Laboratory) inherited its concept from the GRACE (Gravity Recovery and Climate Experiment) mission to determine the gravity field of the Moon. We present lunar gravity fields based on the data of GRAIL's primary mission phase. Gravity field recovery is realized in the framework of the Celestial Mechanics Approach, using a development version of the Bernese GNSS Software along with Ka-band range-rate data series as observations and the GNI1B positions provided by NASA JPL as pseudo-observations. By comparing our results with the official level-2 GRAIL gravity field models we show that the lunar gravity field can be recovered with a high quality by adapting the Celestial Mechanics Approach, even when using pre-GRAIL gravity field models as a priori fields and when replacing sophisticated models of non-gravitational accelerations by appropriately spaced pseudo-stochastic pulses (i.e., instantaneous velocity changes). We present and evaluate two lunar gravity field solutions up to degree and order 200 - AIUB-GRL200A and AIUB-GRL200B. While the first solution uses no gravity field information beyond degree 200, the second is obtained by using the official GRAIL field GRGM900C up to degree and order 660 as a priori information. This reduces the omission errors and demonstrates the potential quality of our solution if we resolved the gravity field to higher degree.

  17. Glass Waveguides for Periodic Poling

    DEFF Research Database (Denmark)

    Fage-Pedersen, Jacob; Jacobsen, Rune Shim; Kristensen, Martin

    2005-01-01

    Planar silica-based waveguide devices have been developed for second-harmonic generation by poling with periodic electrodes. We show that detrimental charge transport can occur along interfaces, but with proper choice of fabrication, high-quality devices are obtained....

  18. Top-quark pole mass

    OpenAIRE

    Smith, Martin C.; Willenbrock, Scott S.

    1996-01-01

    The top quark decays more quickly than the strong-interaction time scale, $\\lqcd^{-1}$, and might be expected to escape the effects of nonperturbative QCD. Nevertheless, the top-quark pole mass, like the mass of a stable heavy quark, is ambiguous by an amount proportional to $\\lqcd$.

  19. Kool pole vabrik / Peeter Kreitzberg

    Index Scriptorium Estoniae

    Kreitzberg, Peeter, 1948-2011

    2003-01-01

    Riigikogu liige Peeter Kreitzberg nimetab Res Publica kavandatavat koolireformi kirvereformiks, mis ei lähtu hariduse põhiprobleemidest. Autor pooldab haridusvõimaluste regionaalset võrdsust ning leiab, et hariduses pole vaja võistlust mõttetult õhutada

  20. On the consistency of the current conventional EOP series and the celestial and terrestrial reference frames

    Science.gov (United States)

    Belda, Santiago; Heinkelmann, Robert; Ferrándiz, José M.; Nilsson, Tobias; Schuh, Harald

    2016-08-01

    Precise transformation between the celestial reference frames (CRF) and terrestrial reference frames (TRF) is needed for many purposes in Earth and space sciences. According to the Global Geodetic Observing System (GGOS) recommendations, the accuracy of positions and stability of reference frames should reach 1 mm and 0.1 mm year^{-1} , and thus, the Earth Orientation Parameters (EOP) should be estimated with similar accuracy. Different realizations of TRFs, based on the combination of solutions from four different space geodetic techniques, and CRFs, based on a single technique only (VLBI, Very Long Baseline Interferometry), might cause a slow degradation of the consistency among EOP, CRFs, and TRFs (e.g., because of differences in geometry, orientation and scale) and a misalignment of the current conventional EOP series, IERS 08 C04. We empirically assess the consistency among the conventional reference frames and EOP by analyzing the record of VLBI sessions since 1990 with varied settings to reflect the impact of changing frames or other processing strategies on the EOP estimates. Our tests show that the EOP estimates are insensitive to CRF changes, but sensitive to TRF variations and unmodeled geophysical signals at the GGOS level. The differences between the conventional IERS 08 C04 and other EOP series computed with distinct TRF settings exhibit biases and even non-negligible trends in the cases where no differential rotations should appear, e.g., a drift of about 20 μ as year^{-1 } in y_{pol } when the VLBI-only frame VTRF2008 is used. Likewise, different strategies on station position modeling originate scatters larger than 150 μ as in the terrestrial pole coordinates.

  1. Territorial Balancing of Poles of Development

    Directory of Open Access Journals (Sweden)

    CLAUDIA POPESCU

    2008-01-01

    Full Text Available The paper is part of the study "Specific problems of the development of the settlement network in south-eastern Romania. Regions of development 3 (South, 4 (South-West and 8 (Bucharest-Ilfov" elaborated during 2004 – 2006, within the AMTRANS programme funded by the Ministry of Education and Research, coordinated by INCD – URBANPROIECT in partnership with the Institute of Geography of the Romanian Academy and the Qualification in Statistics National Centre. The general objective of the project was sustainable and balanced spatial development of the settlement network and promotion of new relationships between urban and rural. Concretely, the study has produced a model of a polycentric and balanced settlement network according to the European principles. The case study testing and validating this model took place in southern Romania, territory exhibiting acutely the entire range of problems related to the state of the settlement network: profoundly large rural areas, accentuated dynamics of declaring new cities without sufficient evidence, excessive polarization exercised by Bucharest, etc. The paper presents the intervention directions needed to balance in the territory urban poles within the studied area, focusing on the establishment of orientation policies to consolidate the role of each settlement based on the hierarchical level of importance: European, national, regional, and local. The paper also identifies possible functional urban areas: the metropolitan area of Bucharest, areas of potential strategic integration, areas of cooperation between the small and medium-sized cities and the rural regions. Within each of these areas, the paper proposes to establish new relationships between urban and rural based on partnership, involving cooperation and coordination in achieving common goals.The study considers that the poles of development are the key element of proposed model, and their identification, formation, and balanced distribution

  2. Resonance poles in three-body systems

    Science.gov (United States)

    Pearce, B. C.; Afnan, I. R.

    1984-12-01

    We develop a method for finding resonance poles in Faddeev equations. The method is computationally simpler than previous methods and is based on the rotation of contour technique. It is applied to πd elastic scattering with coupling to the NΔ channel. The position of the pole is compared with predictions based on Argand diagram and speed analysis. We find that the conventional methods are unreliable if the pole is further from the real axis than the Δ resonance pole.

  3. Pole counting and resonance classification

    International Nuclear Information System (INIS)

    S-wave resonances occurring close to an inelastic threshold can be classified according to the number of nearby poles they possess. One then has a useful possibility of distinguishing dynamical alternatives by objective appeal to data. Making this quantitative entails developing suitable effective range expansions for various realizations of potential scattering. A key application is deciding the make-up of f0 (976) (S*). (author)

  4. Celestial Navigation Fix Based on Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Tsou Ming-Cheng

    2015-09-01

    Full Text Available A technique for solving celestial fix problems is proposed in this study. This method is based on Particle Swarm Optimization from the field of swarm intelligence, utilizing its superior optimization and searching abilities to obtain the most probable astronomical vessel position. In addition to being applicable to two-body fix, multi-body fix, and high-altitude observation problems, it is also less reliant on the initial dead reckoning position. Moreover, by introducing spatial data processing and display functions in a Geographical Information System, calculation results and chart work used in Circle of Position graphical positioning can both be integrated. As a result, in addition to avoiding tedious and complicated computational and graphical procedures, this work has more flexibility and is more robust when compared to other analytical approaches.

  5. Surface Motion Relative to the Irregular Celestial Bodies

    CERN Document Server

    Jiang, Yu; Baoyin, Hexi

    2016-01-01

    We study the motion and equilibria of the grains on the surface of the irregular celestial body (hereafter called irregular bodies). Motions for the grains on the smooth and unsmooth surfaces are discussed, respectively. The linearized equations of motion relative to a surface equilibrium point and its characteristic equations are presented. Considering the stick-slip effect, the damping forces and the spring forces for the grain are calculated, then the linearized equations of motion and the characteristic equations relative to the surface equilibrium points are derived. The number of non-degenerate surface equilibria is an even number. We compute the motion of a grain released above three different regions relative to the irregular asteroid 6489 Golevka, including the flat surface, the concave region, and the convex region. Following the grain release and initial bounce, three kinds of motions exist, the orbital motion, the impact motion and the surface motion. We find that the maximum height of the next ho...

  6. The Pleiades: the celestial herd of ancient timekeepers

    CERN Document Server

    Sparavigna, Amelia

    2008-01-01

    In the ancient Egypt seven goddesses, represented by seven cows, composed the celestial herd that provides the nourishment to her worshippers. This herd is observed in the sky as a group of stars, the Pleiades, close to Aldebaran, the main star in the Taurus constellation. For many ancient populations, Pleiades were relevant stars and their rising was marked as a special time of the year. In this paper, we will discuss the presence of these stars in ancient cultures. Moreover, we will report some results of archeoastronomy on the role for timekeeping of these stars, results which show that for hunter-gatherers at Palaeolithic times, they were linked to the seasonal cycles of aurochs.

  7. Eclipse. The celestial phenomenon that changed the course of history

    Science.gov (United States)

    Steel, Duncan

    Whether interpreted as an auspicious omen or a sentinel of doom, eclipses have had a profound effect upon our cultural development. The pattern that eclipses follow - a cycle, called the Saros - was actually calculated thousands of years ago. However, it is only with the help of modern computers that we have been able to analyze and appreciate the data. Eclipses provide unique opportunities for today's scientists to study such contrasting phenomena as the upper layers of the sun, the slowdown of our planet's spin rate, and the effects of celestial events on human psychology. In Eclipse, Duncan Steel expertly captures our continuing fascination with all manner of eclipses - including the familiar solar and lunar varieties and other kinds involving stars, planets, asteroids, and comets as well as distant galaxies and quasars. Steel helps us see that, in astronomical terms, eclipses are really rather straightforward affairs. Moving beyond the mysticism and the magic, the science of eclipses is revealed.

  8. Exploración o deporte: comparación entre los modelos britanico y noruego en la carrera por alcanzar el polo sur = Exploration or sport: comparision between british and norwegian models in the race to reach the south pole

    Directory of Open Access Journals (Sweden)

    Javier Gálvez González

    2013-03-01

    Full Text Available En este trabajo se analiza la carrera entre Roald Amundsen y Robert F. Scott por alcanzar el Polo Sur entre 1911 y 1912, tomando como base un planteamiento deportivo de organizar la exploración. La expedición de Amundsen fue considerada como moderna, por aplicar los avances existentes para llegar el primero a los 90º Sur. La expedición de Scott sin embargo se organizó según las tradiciones militares británicas. Al final, la victoria del noruego demostró una elección más adecuada de la los factores técnicos, tácticos, biológicos y psicológicos.--------------------------------------------------------------------------------This paper examines the race between Roald Amundsen and Robert F. Scott to reach the South Pole between 1911 and 1912, based on a Sports approach to organize the exploration. Amundsen's expedition was considered as modern to implement existing developments to be the first to get to 90 degrees south. Scott's expedition was organized, however, according to British military traditions. In the end, the Norwegian won, demonstrating a more suitable choice of the technical, tactical, biological and psychological factors.

  9. Celestial Navigation in the USA, Fiji, and Tunisia

    Science.gov (United States)

    Holbrook, Jarita C.

    2015-05-01

    Today there are many coastal communities that are home to navigators who use stars for position finding at night; I was, however, unaware of this fact when I began researching celestial navigation practices in 1997. My project focused on three communities: the Moce Islanders of Fiji, the Kerkennah Islanders in Tunisia, and the U.S. Navy officers and students at the United States Naval Academy, Annapolis, Maryland. My goal was to answer the question of why people continue to navigate by the stars, but also to understand the role of technology in their navigation practices. Using anthropology techniques of ethnography including participant observation, formal and informal interviews, audio and videotaping, I gathered data over five years at the three communities. I began by learning the details of how they use the stars for navigation. Next, I learned about who did the navigation and where they learned to navigate. I gathered opinions on various navigation aids and instruments, and opinions about the future of using the stars for navigation. I listened to the stories that they told about navigating. In the United States I worked in English, in Fiji, in Fijian and English, and in Tunisia, French and English. For the formal interviews I worked with translators. The navigators use stars for navigating today but the future of their techniques is not certain. Though practiced today, these celestial navigation traditions have undergone and continue to undergo changes. New navigational technologies are part of the stimulation for change, thus 'a meeting of different worlds' is symbolized by peoples encounters with these technologies.

  10. Mechanical behaviour of cross-country ski racing poles during double poling.

    Science.gov (United States)

    Stöggl, Thomas; Karlöf, Lars

    2013-11-01

    The purpose of this study was to evaluate the behaviour of cross-country ski poles during double poling on a treadmill using three-dimensional kinematics. The results were compared with standard laboratory tests of the pole manufacturers. A total of 18 skiers were analysed at two speeds (85% and 95% of the maximal speed) at grades of 1.5% and 7%. Variables describing cycle characteristics, bending stiffness, bending behaviour, and trajectories of the pole markers were analysed. Triangular-shaped poles demonstrated the greatest stiffness and lowest variability in maximal bending. Softer poles demonstrated greater variability in bending behaviour and lost ground contact at high skiing speeds, which for some skiers resulted in failure to complete high-speed tests. Considerable variations in pole behaviour for similar poles between skiers were observed, which might be attributed to differences in technique, indicating that mechanical properties of the poles did not exclusively determine pole behaviour in the dynamic situation. The greatest magnitude of pole bending was in the middle part of the pole, which differed from the standard static pole analysis of the manufacturer. Increases in grade demonstrated the greatest effect on pole bending. Distinct differences from the pole manufacturers' laboratory measures were apparent, suggesting that basic pole testing might be adapted.

  11. Mission analysis and systems design of a near-term and far-term pole-sitter mission

    Science.gov (United States)

    Heiligers, Jeannette; Ceriotti, Matteo; McInnes, Colin R.; Biggs, James D.

    2014-01-01

    This paper provides a detailed mission analysis and systems design of a near-term and far-term pole-sitter mission. The pole-sitter concept was previously introduced as a solution to the poor temporal resolution of polar observations from highly inclined, low Earth orbits and the poor high-latitude coverage from geostationary orbit. It considers a spacecraft that is continuously above either the north or south pole and, as such, can provide real-time, continuous and hemispherical coverage of the polar regions. Being on a non-Keplerian orbit, a continuous thrust is required to maintain the pole-sitter position. For this, two different propulsion strategies are proposed, which result in a near-term pole-sitter mission using solar electric propulsion (SEP) and a far-term pole-sitter mission where the SEP thruster is hybridized with a solar sail. For both propulsion strategies, minimum propellant pole-sitter orbits are designed. In order to maximize the spacecraft mass at the start of the operations phase of the mission, the transfer from Earth to the pole-sitter orbit is designed and optimized assuming either a Soyuz or an Ariane 5 launch. The maximized mass upon injection into the pole-sitter orbit is subsequently used in a detailed mass budget analysis that will allow for a trade-off between mission lifetime and payload mass capacity. Also, candidate payloads for a range of applications are investigated. Finally, transfers between north and south pole-sitter orbits are considered to overcome the limitations in observations due to the tilt of the Earth's rotational axis that causes the poles to be alternately situated in darkness. It will be shown that in some cases these transfers allow for propellant savings, enabling a further extension of the pole-sitter mission.

  12. X/Ka Celestial Frame Improvements: Vision to Reality

    Science.gov (United States)

    Jacobs, C. S.; Bagri, D. S.; Britcliffe, M. J.; Clark, J. E.; Franco, M. M.; Garcia-Miro, C.; Goodhart, C. E.; Horiuchi, S.; Lowe, S. T.; Moll, V. E.; Navarro, R.; Rogstad, S. P.; Proctor, R. C.; Sigman, E. H.; Skjerve, L. J.; Soriano, M. A.; Sovers, O. J.; Tucker, B. C.; Wang, D.; White, L. A.

    2010-01-01

    In order to extend the International Celestial Reference Frame from its S/X-band (2.3/8.4 GHz) basis to a complementary frame at X/Ka-band (8.4/32 GHz), we began in mid-2005 an ongoing series of X/Ka observations using NASA s Deep Space Network (DSN) radio telescopes. Over the course of 47 sessions, we have detected 351 extra-galactic radio sources covering the full 24 hours of right ascension and declinations down to -45 degrees. Angular source position accuracy is at the part-per-billion level. We developed an error budget which shows that the main errors arise from limited sensitivity, mismodeling of the troposphere, uncalibrated instrumental effects, and the lack of a southern baseline. Recent work has improved sensitivity by improving pointing calibrations and by increasing the data rate four-fold. Troposphere calibration has been demonstrated at the mm-level. Construction of instrumental phase calibrators and new digital baseband filtering electronics began in recent months. We will discuss the expected effect of these improvements on the X/Ka frame.

  13. Numeric calculation of celestial bodies with spreadsheet analysis

    Science.gov (United States)

    Koch, Alexander

    2016-04-01

    The motion of the planets and moons in our solar system can easily be calculated for any time by the Kepler laws of planetary motion. The Kepler laws are a special case of the gravitational law of Newton, especially if you consider more than two celestial bodies. Therefore it is more basic to calculate the motion by using the gravitational law. But the problem is, that by gravitational law it is not possible to calculate the state of motion with only one step of calculation. The motion has to be numerical calculated for many time intervalls. For this reason, spreadsheet analysis is helpful for students. Skills in programmes like Excel, Calc or Gnumeric are important in professional life and can easily be learnt by students. These programmes can help to calculate the complex motions with many intervalls. The more intervalls are used, the more exact are the calculated orbits. The sutdents will first get a quick course in Excel. After that they calculate with instructions the 2-D-coordinates of the orbits of Moon and Mars. Step by step the students are coding the formulae for calculating physical parameters like coordinates, force, acceleration and velocity. The project is limited to 4 weeks or 8 lessons. So the calcualtion will only include the calculation of one body around the central mass like Earth or Sun. The three-body problem can only be shortly discussed at the end of the project.

  14. Advanced Spacecraft Navigation and Timing Using Celestial Gamma-Ray Sources Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed novel program will use measurements of the high-energy photon output from gamma-ray celestial sources to design a new, unique navigation system. This...

  15. On the nomenclature of celestial objects - not to build the Tower of Babel.

    Science.gov (United States)

    Nishimura, S.

    In order to accumulate and retrieve data relating to celestial objects, it is essential to designate names of objects correctly. The recommendation by the IAU Working Group on the Nomenclature is described.

  16. The Inner Meaning of Outer Space: Human Nature and the Celestial Realm

    OpenAIRE

    Hubbard, Timothy L.

    2008-01-01

    Kant argued that humans possess a priori knowledge of space; although his argument focused on a physics of bodies, it also has implications for a psychology of beings. Many human cultures organize stars in the night sky into constellations (i.e., impose structure); attribute properties, behaviors, and abilities to objects in the celestial realm (i.e., impose meaning); and use perceived regularity in the celestial realms in development of calendars, long-range navigation, agriculture, and astr...

  17. Lunar Pole Illumination and Communications Statistics Computed from GSSR Elevation Data

    Science.gov (United States)

    Bryant, Scott

    2010-01-01

    The Goldstone Solar System RADAR (GSSR) group at JPL produced a Digital Elevation Model (DEM) of the lunar south pole using data obtained in 2006. This model has 40-meter horizontal resolution and about 5-meter relative vertical accuracy. This paper uses that Digital Elevation Model to compute average solar illumination and Earth visibility near the lunar south pole. This data quantifies solar power and Earth communications resources at proposed lunar base locations. The elevation data were converted into local terrain horizon masks, then converted into selenographic latitude and longitude coordinates. The horizon masks were compared to latitude, longitude regions bounding the maximum Sun and Earth motions relative to the moon. Proposed lunar south pole base sites were examined in detail, with the best site showing multi-year averages of solar power availability of 92% and Direct-To-Earth (DTE) communication availability of about 50%. Results are compared with a theoretical model, and with actual sun and Earth visibility averaged over the years 2009 to 2028. Results for the lunar North pole were computed using the GSSR DEM of the lunar North pole produced in 1997. The paper also explores using a heliostat to reduce the photovoltaic power system mass and complexity.

  18. The possibility existence of volatile compounds in the area of NSR S5 spot of local suppression of epithermal neutron flux in the South Pole region of the Moon.

    Science.gov (United States)

    Feoktistova, Ekaterina

    2016-07-01

    6 statistically significant areas in which it was recorded a lower value of the flow of epithermal neutrons was found in the polar regions of the moon according to LEND: 5 areas are located in the south polar region (the area NSR S1 - 5 [1]) and one (area NSR N1[1]) to the north. One of these areas - the area NSR S5 - is located in the landing sector Luna - Globe mission [2], the launch of which is planned by Russian Space Agency in 2018. In this paper, we investigated the temperature regime, illumination conditions and the possibility of the existence of deposits of volatile compounds in this area. To study we selected a number of substances was detected in the LCROSS impact site in the crater Cabeus, particularly compounds such as H2O, CO2, SO2, CH3OH, NH3, C2H4, H2S, CH4 · 5.75H2O and CO · 5.75H2O [3]. We divided the area of NSR S5 spot into a grid with a number of elements. Step in longitude grid was 0.15 degrees, a step in latitude 0.05 degrees. The total number of the elements of the area of the crater is 36000. The height, slope and orientation of each element were calculated based on a LOLA DEM [4] using an algorithm described in [5]. Our results show that the compounds of deposits such as H2O, CO2, SO2, CH3OH, NH3, C2H4, H2S, CH4 · 5.75H2O and CO · 5.75H2O may exist in NSR S5. Thus, the local suppression the epithermal neutron flux in this region may be due to the presence of hydrogen-containing compounds deposits. [1] Mitrofanov et al. (2012) JGR 117, E003956 [2] Ivanov et al. (2014) Solar System Res. 48, 391 - 402 [3] Colaprete et al. (2010) Science 330, 463-468 [4] http://wwwpds.wustl.edu/ [5] Zevenbergen, L.W., Thorne (1987) Earth Surface Processes and Landforms 12(1), 47-56.

  19. Pole position studied with artificial earth satellites.

    Science.gov (United States)

    Gaposchkin, E. M.

    1972-01-01

    Long-arc orbit computation of highest accuracy can provide pole positions. Optical Baker-Nunn and laser range observations of several satellites are combined. The accuracy of the pole position is comparable to that of the mean satellite-tracking station coordinates (plus or minus 5 m) when sufficient tracking data are available. Exploitation of the technique requires more accurate tracking data.

  20. Macro Fiber Piezocomposite Actuator Poling Study

    Science.gov (United States)

    Werlink, Rudy J.; Bryant, Robert G.; Manos, Dennis

    2002-01-01

    The performance and advantages of Piezocomposite Actuators are to provide a low cost, in-situ actuator/sensor that is flexible, low profile and high strain per volt performance in the same plane of poled voltage. This paper extends reported data for the performance of these Macrofiber Composite (MFC) Actuators to include 4 progressively narrower Intedigitized electrode configurations with several line widths and spacing ratios. Data is reported for max free strain, average strain per applied volt, poling (alignment of the electric dipoles of the PZT ceramic) voltage vs. strain and capacitance, time to poling voltage 95% saturation. The output strain per volt progressively increases as electrode spacing decreases, with saturation occurring at lower poling voltages. The narrowest spacing ratio becomes prone to voltage breakdown or short circuits limiting the spacing width with current fabrication methods. The capacitance generally increases with increasing poling voltage level but has high sensitivity to factors such as temperature, moisture and time from poling which limit its usefulness as a simple indicator. The total time of applied poling voltage to saturate or fully line up the dipoles in the piezoceramic was generally on the order of 5-20 seconds. Less sensitivity to poling due to the applied rate of voltage increase over a 25 to 500 volt/second rate range was observed.

  1. Planar glass devices for efficient periodic poling

    DEFF Research Database (Denmark)

    Fage-Pedersen, Jacob; Jacobsen, Rune Shim; Kristensen, Martin

    2005-01-01

    We demonstrate that frequency-converting devices of high quality can be realised with glass poling. The devices, made with silica-on-silicon technology, are poled with periodic, embedded electrodes, and used for second-harmonic generation. We obtain precise control of the quasi phase-matching wav......We demonstrate that frequency-converting devices of high quality can be realised with glass poling. The devices, made with silica-on-silicon technology, are poled with periodic, embedded electrodes, and used for second-harmonic generation. We obtain precise control of the quasi phase......-matching wavelength and bandwidth, and a normalised conversion efficiency of 1.4×10-3 %/W/cm2 which, to our knowledge, is the highest obtained so far with periodic glass poling....

  2. Baryon transition form factors at the pole

    CERN Document Server

    Tiator, L; Workman, R L; Hadžimehmedović, M; Osmanović, H; Omerović, R; Stahov, J; Švarc, A

    2016-01-01

    Electromagnetic resonance properties are uniquely defined at the pole and do not depend on the separation of the resonance from background or the decay channel. Photon-nucleon branching ratios are nowadays often quoted at the pole, and we generalize the considerations to the case of virtual photons. We derive and compare relations for nucleon to baryon transition form factors both for the Breit-Wigner and the pole positions. Using the MAID2007 and SAID SM08 partial wave analyses of pion electroproduction data, we compare the $G_M$, $G_E$, and $G_C$ form factors for the $\\Delta(1232)$ resonance excitation at the Breit-Wigner resonance and pole positions up to $Q^2=5$ GeV$^2$. We also explore the $E/M$ and $S/M$ ratios as functions of $Q^2$. For pole and residue extraction, we apply the Laurent + Pietarinen method.

  3. Pole placement with constant gain output feedback

    Science.gov (United States)

    Sridhar, B.; Lindorff, D. P.

    1972-01-01

    Given a linear time invariant multivariable system with m inputs and p outputs, it was shown that p closed loop poles of the system can be preassigned arbitrarily using constant gain output feedback provided (A circumflex, B circumflex) is controllable. These data show that if (A circumflex, B circumflex, C circumflex) is controllable and observable, and Rank B circumflex = m, Rank C circumflex = p, then max (m,p) poles of the system can be assigned arbitarily using constant gain output feedback. Further, it is shown that in some cases more than max (m,p) poles can be arbitrarily assigned. A least square design technique is outlined to approximate the desired pole locations when it is not possible to place all the poles.

  4. Lunar Pole Illumination and Communications Maps Computed from GSSR Elevation Data

    Science.gov (United States)

    Bryant, Scott

    2009-01-01

    A Digital Elevation Model of the lunar south pole was produced using Goldstone Solar System RADAR (GSSR) data obtained in 2006.12 This model has 40-meter horizontal resolution and about 5-meter relative vertical accuracy. This Digital Elevation Model was used to compute average solar illumination and Earth visibility with 100 kilometers of the lunar south pole. The elevation data were converted into local terrain horizon masks, then converted into lunar-centric latitude and longitude coordinates. The horizon masks were compared to latitude, longitude regions bounding the maximum Sun and Earth motions relative to the moon. Estimates of Earth visibility were computed by integrating the area of the region bounding the Earth's motion that was below the horizon mask. Solar illumination and other metrics were computed similarly. Proposed lunar south pole base sites were examined in detail, with the best site showing yearly solar power availability of 92 percent and Direct-To-Earth (DTE) communication availability of about 50 percent. Similar analysis of the lunar south pole used an older GSSR Digital Elevation Model with 600-meter horizontal resolution. The paper also explores using a heliostat to reduce the photovoltaic power system mass and complexity.

  5. The Inner Meaning of Outer Space: Human Nature and the Celestial Realm

    Directory of Open Access Journals (Sweden)

    Timothy L. Hubbard

    2008-06-01

    Full Text Available Kant argued that humans possess a priori knowledge of space; although his argument focused on a physics of bodies, it also has implications for a psychology of beings. Many human cultures organize stars in the night sky into constellations (i.e., impose structure; attribute properties, behaviors, and abilities to objects in the celestial realm (i.e., impose meaning; and use perceived regularity in the celestial realms in development of calendars, long-range navigation, agriculture, and astrology (i.e., seek predictability and control. The physical inaccessibility of the celestial realm allows a potent source of metaphor, and also allows projection of myths regarding origin and ascension, places of power, and dwelling places of gods, immortals, and other souls. Developments in astronomy and cosmology infl uenced views of human nature and the place of humanity in the universe, and these changes parallel declines in egocentrism with human development. Views regarding alleged beings (e.g., angels, extraterrestrials from the celestial realm (and to how communicate with such beings are anthropocentric and ignore evolutionary factors in physical and cognitive development. It is suggested that in considering views and uses of the celestial realm, we learn not just about the universe, but also about ourselves. *

  6. WASTE MANAGEMENT IN THE PLANT OF THE PAULISTA AGRIBUSINESS TECHNOLOGY AGENCY (APTA - CENTER SOUTH POLE, PIRACICABA - SP = GESTÃO DE RESÍDUOS NAS INSTALAÇÕES DA AGÊNCIA PAULISTA DE TECNOLOGIA DOS AGRONEGÓCIOS (APTA - PÓLO CENTRO SUL, PIRACICABA - SP

    Directory of Open Access Journals (Sweden)

    Nadia Valério Possignolo

    2014-06-01

    Full Text Available This study aimed to establish practices on management of wastes generated in APTA Center South Pole. The passive inventory related to pesticides resulted in a list of 104 active ingredients, among which 16 with law restrictions, stored in inappropriate conditions. In the active inventory related to chemical wastes the generation of solutions containing metals, such as chromium and copper was observed. Due to the chemical precipitation technique, the treatment achieved an efficiency greater than 99,9%, which allowed it to meet the limits established by the environmental legislation. The achievements were promising and demonstrated considerable environmental gain. = Este estudo teve como objetivo estabelecer práticas de gestão de resíduos gerados na APTA Pólo Centro-Sul. O inventário do passivo relacionado com os agrotóxicos resultou em uma lista com 104 ingredientes ativos, dentre os quais 16 com restrições legais, armazenados em condições inadequadas. No inventário do ativo relacionado com resíduos químicos foi observada a geração de soluções contendo metais, tais como o cromo e cobre. A técnica de precipitação química conferiu ao tratamento uma eficiência superior a 99,9%, permitindo atender o limite estabelecido pela legislação. Os resultados alcançados foram promissores e demonstraram um ganho ambiental considerável.

  7. Tree-loop duality relation beyond single poles

    Energy Technology Data Exchange (ETDEWEB)

    Bierenbaum, Isabella [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Buchta, Sebastian; Draggiotis, Petros; Malamos, Ioannis; Rodrigo, German [Valencia Univ. Paterna (Spain). Inst. de Fisica Corpuscular

    2012-11-15

    We develop the Tree-Loop Duality Relation for two- and three-loop integrals with multiple identical propagators (multiple poles). This is the extension of the Duality Relation for single poles and multi-loop integrals derived in previous publications. We prove a generalization of the formula for single poles to multiple poles and we develop a strategy for dealing with higher-order pole integrals by reducing them to single pole integrals using Integration By Parts.

  8. Feynman rules of higher-order poles in CHY construction

    Science.gov (United States)

    Huang, Rijun; Feng, Bo; Luo, Ming-xing; Zhu, Chuan-Jie

    2016-06-01

    In this paper, we generalize the integration rules for scattering equations to situations where higher-order poles are present. We describe the strategy to deduce the Feynman rules of higher-order poles from known analytic results of simple CHY-integrands, and propose the Feynman rules for single double pole and triple pole as well as duplex-double pole and triplex-double pole structures. We demonstrate the validation and strength of these rules by ample non-trivial examples.

  9. Are the orbital poles of binary stars in the solar neighbourhood anisotropically distributed?

    CERN Document Server

    Agati, J-L; Jorissen, A; Soulié, E; Udry, S; Verhas, P; Dommanget, J

    2014-01-01

    We test whether or not the orbital poles of the systems in the solar neighbourhood are isotropically distributed on the celestial sphere. The problem is plagued by the ambiguity on the position of the ascending node. Of the 95 systems closer than 18 pc from the Sun with an orbit in the 6th Catalogue of Orbits of Visual Binaries, the pole ambiguity could be resolved for 51 systems using radial velocity collected in the literature and CORAVEL database or acquired with the HERMES-Mercator spectrograph. For several systems, we can correct the erroneous nodes in the 6th Catalogue of Orbits and obtain new combined spectroscopic-astrometric orbits for seven systems [WDS 01083+5455Aa,Ab; 01418+4237AB; 02278+0426AB (SB2); 09006+4147AB (SB2); 16413+3136AB; 17121+4540AB; 18070+3034AB]. We used of spherical statistics to test for possible anisotropy. After ordering the binary systems by increasing distance from the Sun, we computed the false-alarm probability for subsamples of increasing sizes, from N = 1 up to the full ...

  10. Methods of Celestial Mechanics Volume I: Physical, Mathematical, and Numerical Principles

    CERN Document Server

    Beutler, Gerhard

    2005-01-01

    G. Beutler's Methods of Celestial Mechanics is a coherent textbook for students in physics, mathematics and engineering as well as an excellent reference for practitioners. This Volume I gives a thorough treatment of celestial mechanics and presents all the necessary mathematical details that a professional would need. After a brief review of the history of celestial mechanics, the equations of motion (Newtonian and relativistic versions) are developed for planetary systems (N-body-problem), for artificial Earth satellites, and for extended bodies (which includes the problem of Earth and lunar rotation). Perturbation theory is outlined in an elementary way from generally known mathematical principles without making use of the advanced tools of analytical mechanics. The variational equations associated with orbital motion - of fundamental importance for parameter estimation (e.g., orbit determination), numerical error propagation, and stability considerations - are introduced and their properties discussed in ...

  11. Assessment of structural integrity of wooden poles

    Science.gov (United States)

    Craighead, Ian A.; Thackery, Steve; Redstall, Martin; Thomas, Matthew R.

    2000-05-01

    Despite recent advances in the development of new materials, wood continues to be used globally for the support of overhead cable networks used by telecommunications and electrical utility companies. As a natural material, wood is subject to decay and will eventually fail, causing disruption to services and danger to public and company personnel. Internal decay, due to basidomycetes fungi or attack by termites, can progress rapidly and is often difficult to detect by casual inspection. The traditional method of testing poles for decay involves hitting them with a hammer and listening to the sound that results. However, evidence suggests that a large number of poles are replaced unnecessarily and a significant number of poles continue to fail unexpectedly in service. Therefore, a more accurate method of assessing the structural integrity of wooden poles is required. Over the last 25 years there have been a number of attempts at improving decay detection. Techniques such as ultrasound, drilling X rays etc. have been developed but have generally failed to improve upon the practicality and accuracy of the traditional testing method. The paper describes the use of signal processing techniques to analyze the acoustic response of the pole and thereby determine the presence of decay. Development of a prototype meter is described and the results of initial tests on several hundred poles are presented.

  12. The ICRF-3: Status, Plans, and Multi-wavelength Progress on the next generation Celestial Reference Frame.

    Science.gov (United States)

    Jacobs, Christopher

    2015-08-01

    ICRF-3 seeks to improve upon the highly successful ICRF-2. Our goals are to improve the precision, spatial and frequency coverage relative to the ICRF-2 by 2018. This date is driven by the desire to create radio frames that are ready for comparison with the Gaia optical frame.Several specific actions are underway. A collaboration to improve at S/X-band precision of the Very Long Baseline Array (VLBA) Calibrator Survey's ~2200 sources, which are typically 5 times less precise than the rest of the ICRF-2, is bearing fruit and is projected to yield a factor of 3 improvement in precision. S/X-band southern hemisphere precision improvements are underway with observations using southern antennas such as the AuScope, Warkworth, and HartRAO, South Africa.We also seek to improve radio frequency coverage with X/Ka-band and K-band work. An X/Ka frame of 660 sources now has full sky coverage from the addition of a 2nd southern station in Argentina which is strengthening the southern hemisphere in general. The X/Ka-band frame's precision is now comparable to the ICRF-2 for the 530 sources in common. A K-band collaboration has formed with similar coverage and southern precision goals. By the time of this meeting, we expect K-band to complete full sky coverage with south polar cap observations and to improve spatial density north of -30 deg declination with VLBA observations.On the analysis front, special attention is being given to combination techniques both of Very Long Baseline Interferometry (VLBI) frames and of multiple data types. Consistency of the Celestial Reference Frame (CRF) with the Terrestrial Reference Frame (TRF) and Earth Oreintation Parameters (EOP) is another area of concern. Comparison of celestial frame solutions from various groups is underway in order to identify and correct systematic errors. We will discuss evidence emerging for 100 µas zonal errors in the ICRF2 in the declination range from 0 to -30 deg.Finally, work is underway to identify and

  13. The distribution of faint galaxies near the South Galactic Pole

    International Nuclear Information System (INIS)

    The clustering of galaxies in the MacGillivray and Dodd sample, obtained from COSMOS machine measures, has been investigated using the method of Mead's analysis and dispersion-subdivision curves. The results show two characteristic clustering scale-lengths in the data, with angular sizes approximately 00.12 and approximately 10.00. At the redshift z* = 0.5 (assuming q0 = +1), the corresponding linear dimensions of the features are approximately 3 h-1 and approximately 25 h-1 Mpc respectively. This is interpreted as providing evidence for the second-order clustering of galaxies. Comparison with computer simulations of galaxy fields indicates that this second-order clustering is consistent with a cellular model for superclustering. (author)

  14. 2D Stabilised analytic signal method in DC pole-pole potential data interpretation

    Indian Academy of Sciences (India)

    Paras R Pujari; Rambhatla G Sastry

    2003-03-01

    Using analytic signal method, interpretation of pole-pole secondary electric potentials due to 2D conductive/resistive prisms is presented. The estimated parameters are the location, lateral extent or width and depth to top surface of the prism. Forward modelling is attempted by 2D-Finite Difference method. The proposed stabilised analytic signal algorithm (RES2AS) uses Tikhonov's regularization scheme and FFT routines. The algorithm is tested on three theoretical examples and field data from the campus of Roorkee University. The stability of RES2AS is also tested on synthetic error prone secondary pole-pole potential data.

  15. Cultural Astronomy in Africa South of the Sahara

    Science.gov (United States)

    Holbrook, Jarita

    This chapter examines two foci of cultural astronomy found in Africa south of the Sahara: creation myths and celestial art. The examples highlighted are from the Akan, the Bahima, the Boshongo, the Fon, the Igbo, the Mambila, the Yoruba, and the Zulu people.

  16. Illustrating the phaenomena celestial cartography in antiquity and the Middle Ages

    CERN Document Server

    Dekker, Elly

    2013-01-01

    In this volume all extant celestial maps and globes made before 1500 are described and analysed. It also discusses the astronomical sources involved in making these artefacts in antiquity, the Middle Ages, the Islamic world and the European Renaissance before 1500.

  17. The Gravitational Effects of a Celestial Body with Magnetic Charge and Moment

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The gravitational effects (precession of charge-less particles and deflection of light) in the gravitational field of a celestial body with magnetic charge and moment (CM)are investigated. We found that the magnetic charge always weakens the pure Schwarzschild effects, while the magnetic dipole moment deforms the effects in a more complicated way.

  18. Vladimir I Arnold - Collected Works Representations of Functions, Celestial Mechanics, and KAM Theory 1957-1965

    CERN Document Server

    Arnold, Vladimir I; Khesin, Boris

    2010-01-01

    Vladimir Arnold is one of the great mathematical scientists of our time. He is famous for both the breadth and the depth of his work. At the same time he is one of the most prolific and outstanding mathematical authors. This first volume of his Collected Works focuses on representations of functions, celestial mechanics, and KAM theory.

  19. Pole shifting with constrained output feedback

    International Nuclear Information System (INIS)

    The concept of pole placement plays an important role in linear, multi-variable, control theory. It has received much attention since its introduction, and several pole shifting algorithms are now available. This work presents a new method which allows practical and engineering constraints such as gain limitation and controller structure to be introduced right into the pole shifting design strategy. This is achieved by formulating the pole placement problem as a constrained optimization problem. Explicit constraints (controller structure and gain limits) are defined to identify an admissible region for the feedback gain matrix. The desired pole configuration is translated into an appropriate cost function which must be closed-loop minimized. The resulting constrained optimization problem can thus be solved with optimization algorithms. The method has been implemented as an algorithmic interactive module in a computer-aided control system design package, MVPACK. The application of the method is illustrated to design controllers for an aircraft and an evaporator. The results illustrate the importance of controller structure on overall performance of a control system

  20. New magnet pole shape for isochronous cyclotrons

    International Nuclear Information System (INIS)

    A new design has been developed for shaping pole tips to produce the radially increasing fields required for isochronous cyclotrons. The conventional solid hill poles are replaced by poles mounted over a small secondary gap which tapers radially from maximum at the magnet edge to zero near the center. Field measurements with a model magnet and calculations with the code TRIM show an increase in field at the edge of the magnet without the usual corresponding large increase in fringing, and a radial field shape more nearly field independent than for conventional hills. The flying hills have several advantages for variable energy multiparticle cyclotrons: (1) a large reduction in the power dissipated by isochronizing trim coils; (2) a more constant shape and magnitude flutter factor, eliminating flutter coils and increasing the operating range; and (3) a sharper fall-off of the fringe field, simplifying beam extraction

  1. A 20 GeVs transparent neutrino astronomy from the North Pole?

    CERN Document Server

    Fargion, Daniele

    2011-01-01

    Muon neutrino astronomy is drown within a polluted atmospheric neutrino noise. However at 24 GeV energy atmospheric muon neutrinos, while rising vertically along the terrestrial diameter, should disappear (or be severely depleted) while converting into tau flavor: any rarest vertical 12 GeV muon track at South Pole Deep Core volume, pointing back to North Pole, might be tracing mostly a noise-free astrophysical signal. The corresponding Deep Core 6-7-8-9 channels trigger maybe point in those directions and inside that energy range without much background. Deep Core detector at South Pole, may scan at 18-27GeV energy windows, into a narrow vertical cone for a novel neutrino astronomy almost noise-free, pointing back toward the North Pole.Unfortunately muon at 12 GeV trace their arrival direction mostly spread around an unique string in a zenith-cone solid angle. To achieve also an azimuth angular resolution a two string detection at once is needed. The doubling of the Deep Core string number, (two new arrays o...

  2. Log amplifier with pole-zero compensation

    Science.gov (United States)

    Brookshier, William

    1987-01-01

    A logarithmic amplifier circuit provides pole-zero compensation for improved stability and response time over 6-8 decades of input signal frequency. The amplifier circuit includes a first operational amplifier with a first feedback loop which includes a second, inverting operational amplifier in a second feedback loop. The compensated output signal is provided by the second operational amplifier with the log elements, i.e., resistors, and the compensating capacitors in each of the feedback loops having equal values so that each break point or pole is offset by a compensating break point or zero.

  3. Pole solutions for flame front propagation

    CERN Document Server

    Kupervasser, Oleg

    2015-01-01

    This book deals with solving mathematically the unsteady flame propagation equations. New original mathematical methods for solving complex non-linear equations and investigating their properties are presented. Pole solutions for flame front propagation are developed. Premixed flames and filtration combustion have remarkable properties: the complex nonlinear integro-differential equations for these problems have exact analytical solutions described by the motion of poles in a complex plane. Instead of complex equations, a finite set of ordinary differential equations is applied. These solutions help to investigate analytically and numerically properties of the flame front propagation equations.

  4. Z' near the Z-pole

    OpenAIRE

    Dermisek, Radovan; Kim, Sung-Gi; Raval, Aditi

    2011-01-01

    We present a fit to precision electroweak data in the standard model extended by an additional vector boson, Z', with suppressed couplings to the electron compared to the Z boson, with couplings to the b-quark, and with mass close to the mass of the Z boson. This scenario provides an excellent fit to forward-backward asymmetry of the b-quark measured on the Z-pole and \\pm 2 GeV off the Z-pole, and to lepton asymmetry, A_e, obtained from the measurement of left-right asymmetry for hadronic fin...

  5. The Amateur Astronomer's Introduction to the Celestial Sphere

    Science.gov (United States)

    Millar, William

    2005-12-01

    This introduction to the night sky is for amateur astronomers who desire a deeper understanding of the principles and observations of naked-eye astronomy. It covers topics such as terrestrial and astronomical coordinate systems, stars and constellations, the relative motions of the sky, sun, moon and earth leading to an understanding of the seasons, phases of the moon, and eclipses. Topics are discussed and compared for observers located in both the northern and southern hemispheres. Written in a conversational style, only addition and subtraction are needed to understand the basic principles and a more advanced mathematical treatment is available in the appendices. Each chapter contains a set of review questions and simple exercises to reinforce the reader's understanding of the material. The last chapter is a set of self-contained observation projects to get readers started with making observations about the concepts they have learned. William Charles Millar, currently Professor of Astronomy at Grand Rapids Community College in Michigan, has been teaching the subject for almost twenty years and is very involved with local amateur astronomy groups. Millar also belongs to The Planetary Society and the Astronomical Society of the Pacific and has traveled to Europe and South America to observe solar eclipses. Millar holds a Masters degree in Physics from Western Michigan University.

  6. Kosovo : kannatlikkusele lootmine pole plaan / Chris Patten

    Index Scriptorium Estoniae

    Patten, Chris

    2007-01-01

    Autor leiab, et arvestades Kosovo elanike ülekaalukat soovi olla vaba Serbiast, riigist, mis üritas nad kõrvaldada, ning alternatiivi täielikku puudumist Belgradi poolt, pole rahvusvahelisel kogukonnal muud võimalust kui anda Kosovole iseseisvus

  7. Poling of planar silica-based waveguides

    DEFF Research Database (Denmark)

    Arentoft, Jesper; Leistiko, Otto

    2000-01-01

    Planar silica-based waveguides were electrically poled at elevated temperatures and cooled with the field still applied. This procedure induced second-order nonlinear effects in the waveguides. Systematic studies of the dependence of the induced linear electro-optic effect on polilng temperature...

  8. NATO pole suutnud Gaddafit murda / Evelyn Kaldoja

    Index Scriptorium Estoniae

    Kaldoja, Evelyn, 1980-

    2011-01-01

    Liibüa diktaatori Muammar Gaddafi režiim pole langenud, Lääneriigid jätkavad sõjalisi operatsioone tsiviilelanike kaitseks. Kolm võimalikku lahendust Liibüa kriisile, BBC diplomaatiakorrespondendi Jonathan Marcuse hinnang

  9. Remarks on pole trajectories for resonances

    Directory of Open Access Journals (Sweden)

    C. Hanhart

    2014-12-01

    This study is of current relevance especially in strong interaction physics, since lattice QCD may be employed to deduce the pole trajectories for hadronic resonances as a function of the quark mass thus providing additional, new access to the structure of s-wave resonances.

  10. Temperament and living conditions: a comparison study of Poles and Koreans.

    Science.gov (United States)

    Zajenkowska, Anna; Zajenkowski, Marcin

    2013-02-01

    The present investigation tested the temperament traits of 319 Polish and 315 South Korean students according to the regulative theory of temperament. Poland and South Korea are two countries with a similar rate of economic growth but with distinct cultures; for instance, they differ in terms of individualism and masculinity dimensions as well as living conditions. This means that they have achieved the same goal with different resources but presumably also with different side effects. The results indicate that the Poles had higher levels of briskness, sensor sensibility and endurance, as well as lower levels of emotional reactivity and perseveration in comparison with South Koreans. The structure of one's temperament determines one's ability to meet environmental requirements and also how one deals with stressful conditions. According to previous empirical data, Poles' temperament profile can be characterized as being less prone to stress perception and therefore more advantageous. It is possible that Koreans, as they have a less adaptive temperament structure, experience higher levels of stress in a more stimulating environment than Poles.

  11. [The celestial phenomena in A. Dürer's engraving Melancholia I].

    Science.gov (United States)

    Weitzel, Hans

    2009-01-01

    The celestial body of Dürer's engraving Melencolia I is connected with his painting of a meteor, the Raveningham-painting; it is shown that the origin of this painting owns to the impact of the meteor of Ensisheim in 1492. Until now the celestial body, the balance, and the magic square are nearly consistently interpreted as the planet Saturn, the zodiac sign Libra, and the planet Jupiter, and the melancholy woman is subject to these heavenly bodies. Consequently, neoplatonic astrology has been the main focus of the engraving; including the rainbow, the engraving has also been interpreted biblically. The present paper, however, places emphasis on problems of the geometry as the reason of melancholy. Any astronomical meaning of the configuration of the numbers of the magic square is discarded. PMID:20336927

  12. Teaching Celestial Motions in Astronomy 101 using the Digital Fulldome Planetarium Environment

    Science.gov (United States)

    Balonek, Thomas J.; Eakin, J.

    2012-01-01

    We utilize the immersive fulldome digital planetarium capabilities of the Colgate University Ho Tung Visualization Laboratory (VisLab) in introductory astronomy courses to teach students about observable celestial motions. We are developing demonstrations and exercises in which students conduct realistic "observations" in the VisLab that complement observations that they make outside on clear nights. From these observations students determine the characteristics and time scales of motions of the various solar system objects. Using the VisLab it is possible for the students to observe the daily, monthly, annual and peculiar motions of the stars, Sun, Moon and planets that they would otherwise be unable to witness during the semester. Our "observation first" approach is to have students observe the various cycles of the sky early in the semester, and later explain the reasons for these motions when they learn about the historical developments in our understanding of the celestial motions.

  13. IN-FLIGHT ALIGNMENT OF INERTIAL NAVIGATION SYSTEM BY CELESTIAL OBSERVATION TECHNIQUE

    Institute of Scientific and Technical Information of China (English)

    ALlJamshaid; FANGJian-cheng

    2005-01-01

    This paper presents an in-flight alignment technique for a strapdown inertial navigation system (SINS) and employs a star pattern recognition procedure for identifying stars sensed by a CCD electrooptical star sensor.Collinearity equations are used to estimate sensor frame star coordinates and the conventional least square differential correction method is used to estimate the unknown orientation angles. A comparison of this attitude with the attitude estimated by the SINS provides axis misalignment angles. Simulations using a Kalman filter are carried out for an SINS and the system employs a local level navigation frame. The space stabilized SINS is discussed in conjunction with the celestial aiding. Based on the observation of the Kalman filter, the estimating and compensating gyro errors, as well as the position and velocity errors caused by the SINS misalignments are calibrated by celestial attitute information.

  14. Periodic Orbits, Stability and Bifurcations in the Potential Field of Highly Irregular-shaped Celestial Bodies

    CERN Document Server

    Jiang, Yu; Baoyin, Hexi

    2014-01-01

    This paper studies the distribution of characteristic multipliers, the stability of orbits, periodic orbits, the structure of submanifolds, the phase diagram, bifurcations and chaotic motions in the potential field of rotating highly irregular-shaped celestial bodies. The topological structure of submanifolds for the orbits in the potential field of a rotating highly irregular-shaped celestial body(hereafter irregular body for short) is discovered that it can be classified into 34 different cases, including 6 ordinary cases, 3 collisional cases, 3 degenerate real saddle cases, 7 periodic cases, 7 period-doubling cases, 1 periodic and collisional case, 1 periodic and degenerate real saddle case, 1 period-doubling and collisional case, 1 period-doubling and degenerate real saddle case as well as 4 periodic and period-doubling cases. It is found that the different distribution of characteristic multipliers fixes the structure of submanifolds, the types of orbits, the dynamical behavior and the phase diagram of t...

  15. Heavenly Networks. Celestial Maps and Globes in Circulation between Artisans, Mathematicians, and Noblemen in Renaissance Europe.

    Science.gov (United States)

    Gessner, Samuel

    2015-01-01

    The aim of this paper is to examine the iconography on a set of star charts by Albrecht Dürer (1515), and celestial globes by Caspar Vopel (1536) and Christoph Schissler (1575). The iconography on these instruments is conditioned by strong traditions which include not only the imagery on globes and planispheres (star charts), but also ancient literature about the constellations. Where this iconography departs from those traditions, the change had to do with humanism in the sixteenth century. This "humanistic" dimension is interwoven with other concerns that involve both "social" and "technical" motivations. The interplay of these three dimensions illustrates how the iconography on celestial charts and globes expresses some features of the shared knowledge and shared culture between artisans, mathematicians, and nobles in Renaissance Europe.

  16. A Renaissance celestial globe as an analogue computer for determination of the coordinates on the heaven

    Science.gov (United States)

    Bartha, Lajos

    Around 1480 the Dominican astronomer and instrument maker Hans Dorn in Castle Buda (Budapest) built a copper celestial globe. This globe is a composite instrument, suited to mark the position of celestial bodies - - i.e. comets, planets, etc. - directly on the star-globe, and to locate the stars represented on the globe in the sky. The globe has a diameter of 39.5 cm and gives the fixed stars according to Ptolemy. The main circles are set in for the celestial equator and ecliptic. On the top of the vertical meridian circle (divided into 4 x 90^o) is a planispheric astrolabe on a strong perpendicular axis. On the reverse side of the astrolabe the altitude arcs can be set by a diopter. Two quadrants with arc-scales protrude downward in horseshoe shape, parallel to the globe, from the bottom of the astrolabe. The divided quadrants parallel to the disk of the astrolabe point to the horizontal 'calendar' disk of the globe and can be turned with the astrolabe to indicate the azimuth. When the globe is adjusted to a given instant of time, the position of a celestial body can be determined by turning the astrolabe and the diopter to the object. The quadrant then shows - with the 'calendar' disk and the quadrant's graduation seen parallel to the mater - the position on the globe either for a planet, a comet, or even a fixed star. Both globe and astrolabe enable one to fix the position of the heavenly bodies directly without the necessity of coordinate transformation. Father Dorn (Saxonia, ca.1425 - Vienna, after 1509) built the combined `analogue computer globe' for the court astrologer of the Hungarian King Matthias Corvinus, magister Martinus Olkusz z Bylica (also called Martinus Ilkusz). Today the globe is in the Museum of Collegium Maius at Cracow.

  17. OPTICAL SPECTRA OF CANDIDATE INTERNATIONAL CELESTIAL REFERENCE FRAME (ICRF) FLAT-SPECTRUM RADIO SOURCES

    Energy Technology Data Exchange (ETDEWEB)

    Titov, O.; Stanford, Laura M. [Geoscience Australia, P.O. Box 378, Canberra, ACT 2601 (Australia); Johnston, Helen M.; Hunstead, Richard W. [Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW 2006 (Australia); Pursimo, T. [Nordic Optical Telescope, Nordic Optical Telescope Apartado 474E-38700 Santa Cruz de La Palma, Santa Cruz de Tenerife (Spain); Jauncey, David L. [CSIRO Astronomy and Space Science, ATNF and Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia); Maslennikov, K. [Central Astronomical Observatory at Pulkovo, Pulkovskoye Shosse, 65/1, 196140, St. Petersburg (Russian Federation); Boldycheva, A., E-mail: oleg.titov@ga.gov.au [Ioffe Physical Technical Institute, 26 Polytekhnicheskaya, St. Petersburg, 194021 (Russian Federation)

    2013-07-01

    Continuing our program of spectroscopic observations of International Celestial Reference Frame (ICRF) sources, we present redshifts for 120 quasars and radio galaxies. Data were obtained with five telescopes: the 3.58 m European Southern Observatory New Technology Telescope, the two 8.2 m Gemini telescopes, the 2.5 m Nordic Optical Telescope (NOT), and the 6.0 m Big Azimuthal Telescope of the Special Astrophysical Observatory in Russia. The targets were selected from the International VLBI Service for Geodesy and Astrometry candidate International Celestial Reference Catalog which forms part of an observational very long baseline interferometry (VLBI) program to strengthen the celestial reference frame. We obtained spectra of the potential optical counterparts of more than 150 compact flat-spectrum radio sources, and measured redshifts of 120 emission-line objects, together with 19 BL Lac objects. These identifications add significantly to the precise radio-optical frame tie to be undertaken by Gaia, due to be launched in 2013, and to the existing data available for analyzing source proper motions over the celestial sphere. We show that the distribution of redshifts for ICRF sources is consistent with the much larger sample drawn from Faint Images of the Radio Sky at Twenty cm (FIRST) and Sloan Digital Sky Survey, implying that the ultra-compact VLBI sources are not distinguished from the overall radio-loud quasar population. In addition, we obtained NOT spectra for five radio sources from the FIRST and NRAO VLA Sky Survey catalogs, selected on the basis of their red colors, which yielded three quasars with z > 4.

  18. From Celestial Empire to Nation State: Sport and the Origins of Chinese Nationalism (1840–1927)

    OpenAIRE

    Zhouxiang, Lu

    2010-01-01

    The history of the late Qing Dynasty and the early Republic clearly showed the close relationship between sport, nationalism and politics, and reflected the changes in Chinese society and Chinese people’s view of their identity as well as their way of thinking. Sport had a great importance, not only for the construction of Chinese nationalism and national consciousness, but also for the eventual transformation of China from a celestial empire into a modern nation state. It play...

  19. The Hands of the Pleiades: The Celestial Clock in the Classical Arabic Poetry of Dhū al-Rumma

    Science.gov (United States)

    Adams, W. B.

    2011-06-01

    In the desert poetry of Dhū al-Rumma (d. 117 AH/735 CE), astronomical phenomena sometimes function as familiar celestial timepieces that indicate the poetic timeframe literally and accurately. The literary, lexical, floral and astronomical analyses of a selection from this poetry illustrate the role of the Pleiades star cluster as a celestial clock and illuminate the utility of naked-eye astronomy in interpreting Arabic poetry of the early Islamic period.

  20. Pole orientation, sidereal period, and sense of rotation of asteroids

    Science.gov (United States)

    Taylor, R. C.; Gehrels, T.

    1986-01-01

    Pole orientations of asteroids were determined. The method, called photometric astrometry, takes precise epochs of lightcurves into account. Pole determination research on asteroids 532 Herculina, 45 Eugenia, and 3 Juno continues. Discrepancies between various pole determination techniques presently being used are analyzed. The study of asteroid shapes and creating a generalized master pole determination technique also continues which will incorporate the best features of several current methods.

  1. Large second-harmonic generation in thermally poled silica waveguides

    DEFF Research Database (Denmark)

    Arentoft, Jesper; Kristensen, Martin; Pedersen, K.;

    2001-01-01

    We report the observation of very large second-harmonic signals from thermally poled silica waveguide samples. Secondary ion mass spectrometry measurements show that significant amounts of silver ions are injected from the top electrode during poling.......We report the observation of very large second-harmonic signals from thermally poled silica waveguide samples. Secondary ion mass spectrometry measurements show that significant amounts of silver ions are injected from the top electrode during poling....

  2. Second-harmonic imaging of poled silica waveguides

    DEFF Research Database (Denmark)

    Arentoft, Jesper; Pedersen, Kjeld; Bozhevolnyi, Sergey I.;

    2000-01-01

    Electric-field poled silica-based waveguides are characterized by measurements of second-harmonic generation (SHG) and of the linear electro-optic effect (LEO). A SHG scanning technique allowing for high-resolution imaging of poled devices is demonstrated. Scans along the direction of the poling...

  3. Efficient iterative adaptive pole placement algorithm

    Institute of Scientific and Technical Information of China (English)

    李俊民; 李靖; 杨磊

    2004-01-01

    An iterative adaptive pole placement algorithm is presented. The stability and the convergence of the algorithm are respectively established. Since one-step iterative formulation in computing controller's parameters is used, the on-line computation cost is greatly reduced with respected to the traditional algorithm. The algorithm with the feed-forward can follow arbitrarily bounded output. The algorithm is also extended to multivariate case. Simulation examples show the efficiency and robustness of the algorithm.

  4. Contact poling of RKTP with silicon pillars

    OpenAIRE

    Kianirad, Hoda; Zukauskas, Andrius; Frisk, Thomas; Canalias, Carlota; Laurell, Fredrik

    2013-01-01

    Quasi-phase-matching (QPM) is a method to get tailored efficient second order nonlinear interactions [1]. Several techniques exist for fabrication of periodic domain structures in ferroelectric crystals for QPM frequency conversion. By far, electric field poling using lithographically patterned electrodes on the z-face of the crystal is the most common one [2]. High-quality periodically inverted ferroelectric domain structures in flux grown KTiOP 4 (KTP) crystals were fabricated already in th...

  5. Risk of Adverse Health and Performance Effects of Celestial Dust Exposure

    Science.gov (United States)

    Scully, Robert R.; Meyers, Valerie E.

    2015-01-01

    Crew members can be directly exposed to celestial dust in several ways. After crew members perform extravehicular activities (EVAs), they may introduce into the habitat dust that will have collected on spacesuits and boots. Cleaning of the suits between EVAs and changing of the Environmental Control Life Support System filters are other operations that could result in direct exposure to celestial dusts. In addition, if the spacesuits used in exploration missions abrade the skin, as current EVA suits have, then contact with these wounds would provide a source of exposure. Further, if celestial dusts gain access to a suit's interior, as was the case during the Apollo missions, the dust could serve as an additional source of abrasions or enhance suit-induced injuries. When a crew leaves the surface of a celestial body and returns to microgravity, the dust that is introduced into the return vehicle will "float," thus increasing the opportunity for ocular and respiratory injury. Because the features of the respirable fraction of lunar dusts indicate they could be toxic to humans, NASA conducted several studies utilizing lunar dust simulants and authentic lunar dust to determine the unique properties of lunar dust that affect physiology, assess the dermal and ocular irritancy of the dust, and establish a permissible exposure limit for episodic exposure to airborne lunar dust during missions that would involve no more than 6 months stay on the lunar surface. Studies, with authentic lunar soils from both highland (Apollo 16) and mare (Apollo17) regions demonstrated that the lunar soil is highly abrasive to a high fidelity model of human skin. Studies of lunar dust returned during the Apollo 14 mission from an area of the moon in which the soils were comprised of mineral constituents from both major geological regions (highlands and mares regions) demonstrated only minimal ocular irritancy, and pulmonary toxicity that was less than the highly toxic terrestrial crystalline

  6. Pole-placement with constant gain output feedback

    Science.gov (United States)

    Sridhar, B.; Lindorff, D. P.

    1973-01-01

    Davison (1970) has demonstrated that it is possible to assign max (m, p) poles of a linear time-invariant controllable and observable multivariable system arbitrarily close to desired locations by using constant gain output feedback. A new proof of Davison's theorem on pole placement is developed, and a system design procedure is described which offers some advantages over Davison's method. It is shown that in some cases more than max (m, p) poles can be assigned arbitrarily, and a least square design procedure is proposed to approximate the desired pole locations when it is not possible to place all the poles.

  7. Growth Poles - an Alternative to Reducing Regional Disparities. Case Study-Iaşi Growth Pole

    Directory of Open Access Journals (Sweden)

    NICOLETA MONICA MUSTĂȚEA

    2013-01-01

    Full Text Available The current development of the European Union is based on the cohesion policy which focuses on the attenuation of regional disparities. For this purpose, the idea of growth poles emerged in Romania, and its role became more than familiar: the determination of an internal socio-economic cohesion. Polycentrism becomes a concept of territorial planning increasingly promoted. Development of growth poles aims to reduce the attraction force of large centres and to balance the location of activities generating functions across a territory. This was the idea that led to the formation of Iaşi Metropolitan Area, territorial unit that is intended to be the main regional centre of the North-East Region, thus polarizing the surrounding areas. Iaşi Growth Pole objectives are represented by economic competitiveness, the development of regional connectivity and the promotion of regional cooperation. One of the major assets of the growth pole in achieving these goals is the cross-border position near the eastern border of the European Union. This paper examines to what extent Iași Growth Pole can rise to the required standards, while the peripheral position seems to be rather a disadvantage and the uncertain functionality of the metropolitan area shows that the main problem remains the reduced economic competitiveness.

  8. Purification of fluorescently labeled Saccharomyces cerevisiae Spindle Pole Bodies

    Science.gov (United States)

    Davis, Trisha N.

    2016-01-01

    Centrosomes are components of the mitotic spindle responsible for organizing microtubules and establishing a bipolar spindle for accurate chromosome segregation. In budding yeast, Saccharomyces cerevisiae, the centrosome is called the spindle pole body, a highly organized tri-laminar structure embedded in the nuclear envelope. Here we describe a detailed protocol for the purification of fluorescently labeled spindle pole bodes from S. cerevisiae. Spindle pole bodies are purified from yeast using a TAP-tag purification followed by velocity sedimentation. This highly reproducible TAP-tag purification method improves upon previous techniques and expands the scope of in vitro characterization of yeast spindle pole bodies. The genetic flexibility of this technique allows for the study of spindle pole body mutants as well as the study of spindle pole bodies during different stages of the cell cycle. The ease and reproducibility of the technique makes it possible to study spindle pole bodies using a variety of biochemical, biophysical, and microscopic techniques. PMID:27193850

  9. Using Time Zones and Celestial Navigation to Teach the Phases of the Moon

    Science.gov (United States)

    O'Donoghue, A.

    2011-09-01

    The phases of the moon are typically presented to introductory astronomy classes in a diagram showing the position of the moon, its appearance and elongation at each phase, and the time of each phase's transit. Though wonderfully compact and efficient at conveying information, I have found it to be overwhelming to non-science major students. Much of their difficulty arises from their vague definition of time, which must be broadened for them to understand the different rising, transit, and setting times for the phases of the moon. Working with time zones helps them recognize that the time on their watch is relative to a particular longitude and the transit of the sun at that longitude. Celestial Navigation extends this to the transit of all celestial objects and helps them re-define "time of day" to a position on Earth relative to the Earth-Sun line in a practical way. Once they understand why a given object transits at the same time for all time zones, extending this to the moon is much simpler. My students are quickly able to identify the transit times of the various phases of the moon, and with some additional instruction, quickly learn how to figure out their rising and setting times as well. On this poster, I will include images from PowerPoint animations and the student exercises I use to help them understand the concepts. Though I have too small a sample for statistical analysis (24 students/semester), I have found that student scores on moon phase questions on exams have improved since I incorporated time zones and celestial navigation into my course.

  10. Perturbing rational harmonic functions by poles

    CERN Document Server

    Sète, Olivier; Liesen, Jörg

    2014-01-01

    We study how adding certain poles to rational harmonic functions of the form $R(z)-\\bar{z}$, with $R(z)$ rational and of degree $d\\geq 2$, affects the number of zeros of the resulting functions. Our results are motivated by and generalize a construction of Rhie derived in the context of gravitational microlensing (ArXiv e-print 2003). Of particular interest is the construction and the behavior of rational functions $R(z)$ that are {\\em extremal} in the sense that $R(z)-\\bar{z}$ has the maximal possible number of $5(d-1)$ zeros.

  11. Celestial harvest 300-plus showpieces of the heavens for telescope viewing and contemplation

    CERN Document Server

    Mullaney, James

    2012-01-01

    This book describes over 300 celestial wonders that can be viewed with common binoculars and low-power ""backyard"" telescopes incorporating refractors and reflectors.In addition to such showpieces as the Andromeda Galaxy, the largest and brightest of all galaxies after the Milky Way, and the Blue Snowball, one of the autumn sky's outstanding planetary nebulas, over 20 other special objects are listed and characterized, many of which are visible to the unaided eye on a dark, clear night.The sun, moon, Venus, Mars, Jupiter, Saturn, and other members of the earth's solar system are also describ

  12. Micro-arcsecond Celestial Reference Frames: definition and realization - Impact of the recent IAU Resolutions

    Institute of Scientific and Technical Information of China (English)

    Nicole Capitaine

    2012-01-01

    The adoption of the International Celestial Reference System (ICRS),based on Very Long Baseline Interferometry (VLBI) observations of extragalactic radiosources by the International Astronomical Union (IAU) since 1998 January 1,opened a new era for astronomy.The ICRS and the corresponding frame,the International Celestial Reference Frame (ICRF),replaced the Fundamental Catalog (FK5) based on positions and proper motions of bright stars,with the Hipparcos catalog being adopted as the primary realization of the ICRS in optical wavelengths.According to its definition,the ICRS is such that the barycentric directions of distant extragalactic objects show no global rotation with respect to these objects; this provides a quasi-inertial reference for measuring the positions and angular motions of the celestial objects.Other resolutions on reference systems were passed by the IAU in 2000 and 2006 and endorsed by the International Union of Geodesy and Geophysics (IUGG) in 2003 and 2007,respectively.These especially concern the definition and realization of the astronomical reference systems in the framework of general relativity and transformations between them.First,the IAU 2000 resolutions refined the concepts and definition of the astronomical reference systems and parameters for Earth's rotation,and adopted the IAU 2000 precession-nutation.Then,the IAU 2006 resolutions adopted a new precession model that is consistent with dynamical theories; they also addressed definition,terminology or orientation issues relative to reference systems and time scales that needed to be specified after the adoption of the IAU 2000 resolutions.An additional IUGG 2007 resolution defined the International Terrestrial Reference System (ITRS) so that it strictly complies with the IAU recommendations.Finally,the IAU 2009 resolutions adopted a new system of astronomical constants and an improved realization of the ICRF.These fundamental changes have led to significant improvements in the fields

  13. Micro-arcsecond Celestial Reference Frames: definition and realization — Impact of the recent IAU Resolutions

    International Nuclear Information System (INIS)

    The adoption of the International Celestial Reference System (ICRS), based on Very Long Baseline Interferometry (VLBI) observations of extragalactic radiosources by the International Astronomical Union (IAU) since 1998 January 1, opened a new era for astronomy. The ICRS and the corresponding frame, the International Celestial Reference Frame (ICRF), replaced the Fundamental Catalog (FK5) based on positions and proper motions of bright stars, with the Hipparcos catalog being adopted as the primary realization of the ICRS in optical wavelengths. According to its definition, the ICRS is such that the barycentric directions of distant extragalactic objects show no global rotation with respect to these objects; this provides a quasi-inertial reference for measuring the positions and angular motions of the celestial objects. Other resolutions on reference systems were passed by the IAU in 2000 and 2006 and endorsed by the International Union of Geodesy and Geophysics (IUGG) in 2003 and 2007, respectively. These especially concern the definition and realization of the astronomical reference systems in the framework of general relativity and transformations between them. First, the IAU 2000 resolutions refined the concepts and definition of the astronomical reference systems and parameters for Earth's rotation, and adopted the IAU 2000 precession-nutation. Then, the IAU 2006 resolutions adopted a new precession model that is consistent with dynamical theories; they also addressed definition, terminology or orientation issues relative to reference systems and time scales that needed to be specified after the adoption of the IAU 2000 resolutions. An additional IUGG 2007 resolution defined the International Terrestrial Reference System (ITRS) so that it strictly complies with the IAU recommendations. Finally, the IAU 2009 resolutions adopted a new system of astronomical constants and an improved realization of the ICRF. These fundamental changes have led to significant

  14. The ICRF-3: Status, plans, and progress on the next generation International Celestial Reference Frame

    CERN Document Server

    Malkin, Z; Arias, F; Boboltz, D; Boehm, J; Bolotin, S; Bourda, G; Charlot, P; De Witt, A; Fey, A; Gaume, R; Heinkelmann, R; Lambert, S; Ma, C; Nothnagel, A; Seitz, M; Gordon, D; Skurikhina, E; Souchay, J; Titov, O

    2015-01-01

    The goal of this presentation is to report the latest progress in creation of the next generation of VLBI-based International Celestial Reference Frame, ICRF3. Two main directions of ICRF3 development are improvement of the S/X-band frame and extension of the ICRF to higher frequencies. Another important task of this work is the preparation for comparison of ICRF3 with the new generation optical frame GCRF expected by the end of the decade as a result of the Gaia mission.

  15. Design of a portable CAT scanner for utility pole inspection

    International Nuclear Information System (INIS)

    Work is under way at the University of Missouri, Columbia (UMC) to design, build, and test a portable computerized axial tomography (CAT) device for the nondestructive, field imaging of wooden utility poles. CAT is a well-established medical technology that has recently been applied to a number of industrial applications. Wooden utility poles are prone to rot and decay at ground level; current techniques to assess this loss of strength are relatively primitive, i.e., tapping the pole (hitting the pole with a hammer) or boring into the pole for samples and then testing inside the bore hole with an electrical pulse device. The accuracy in identifying poles needing replacement using these techniques is ∼ 70%. Since the cost of replacing a pole ranges from hundreds to thousands of dollars, an accurate, nondestructive method is needed. CAT can accurately image a wooden utility pole (since the size, density, and atomic elements of a pole are similar to the human head to torso), as was confirmed by imaging poles using the UMC nuclear engineering EMI-1010 medical scanner. Detailed images have been produced showing the ring structure of the wood and voids due to rot or decay. Images approaching this quality have also been produced on living trees using semiportable systems by other researchers

  16. The Pole Orientation, Pole Precession, and Moment of Inertia Factor of Saturn

    Science.gov (United States)

    Jacobson, R. A.; French, R. G.; Nicholson, P. D.; Hedman, M.; Colwell, J. E.; Marouf, E.; Rappaport, N.; McGhee, C.; Sepersky, T.; Lonergan, K.

    2011-01-01

    This paper discusses our determination of the Saturn's pole orientation and precession using a combination of Earthbased and spacecraft based observational data. From our model of the polar motion and the observed precession rate we obtain a value for Saturn's polar moment of inertia

  17. a New Ediacaran Pole from Easternmost Baltica

    Science.gov (United States)

    Meert, J. G.; Levashova, N. M.; Kuznetsov, N. B.; Sergeeva, N. D.; Golovanova, I. V.; Danukalov, K. N.; Bazhenov, M. L.

    2011-12-01

    Ediacaran paleogeography is notoriously messy due to equally confusing paleomagnetic data from both Laurentia and Baltica. Ediacaran (~Vendian) rocks have been studied from several localities from Baltica, but the so far published poles can be used to place the Baltic craton at nearly any latitude and orientation [Meert et al., 2007]. At the same time, it is challenging to understand the paleogeography of the Ediacaran world given all the biologic, climatic and tectonic changes during the time interval from 635-542 Ma. We present preliminary paleomagnetic and geochronological data from (late?) Ediacaran sediments from the deformed (low metamorphic grade) peri-Uralian margin of Baltica. We successfully isolated a dual-polarity high-temperature component from eleven sites; the primary origin of this remanence is strongly supported by a positive reversal test (class B). The corresponding paleomagnetic pole is in close agreement with the coeval results from the Winter Coast of northern Baltica [Popov et al., 2002; 2005; Iglesia Llanos et al., 2005], despite a ~1600 km separation between two study areas. These data jointly indicate a very low (<10 degrees N or S) paleolatitude for eastern Baltica in Ediacaran time. Paleogeographic implications of these new data will be discussed in the context of Ediacaran-Cambrian tectonic models. This study is supported by RFBR grant 11-05-00037 and NSF grant EAR11-19038.

  18. Měření intenzity pole

    OpenAIRE

    Novák, Tomáš

    2009-01-01

    V této práci podrobně rozebereme problematiku měření intenzity pole a to hlavně v krátkovlnném pásmu přijímaných kmitočtů. Pro měření intenzity elektrického pole je nutné použít vhodnou anténu, která svými vlastnostmi a parametry nejlépe vyhovuje požadavkům na toto měření. Tyto požadavky jsou rozebrány v úvodní části této práce. Z těchto požadavků vyplynulo jedno konkrétní řešení, které je vhodné pro tuto problematiku. Tímto řešením je rámová anténa, která nejlépe splňuje požadavky toho to mě...

  19. Optimization design about gimbal structure of high-precision autonomous celestial navigation tracking mirror system

    Science.gov (United States)

    Huang, Wei; Yang, Xiao-xu; Han, Jun-feng; Wei, Yu; Zhang, Jing; Xie, Mei-lin; Yue, Peng

    2016-01-01

    High precision tracking platform of celestial navigation with control mirror servo structure form, to solve the disadvantages of big volume and rotational inertia, slow response speed, and so on. It improved the stability and tracking accuracy of platform. Due to optical sensor and mirror are installed on the middle-gimbal, stiffness and resonant frequency requirement for high. Based on the application of finite element modality analysis theory, doing Research on dynamic characteristics of the middle-gimbal, and ANSYS was used for the finite element dynamic emulator analysis. According to the result of the computer to find out the weak links of the structure, and Put forward improvement suggestions and reanalysis. The lowest resonant frequency of optimization middle-gimbal avoid the bandwidth of the platform servo mechanism, and much higher than the disturbance frequency of carrier aircraft, and reduces mechanical resonance of the framework. Reaching provides a theoretical basis for the whole machine structure optimization design of high-precision of autonomous Celestial navigation tracking mirror system.

  20. Nonlinear effect induced in thermally poled glass waveguides

    Institute of Scientific and Technical Information of China (English)

    REN Yi-tao

    2006-01-01

    Thermally poled germanium-doped channel waveguides are presented. Multilayer waveguides containing a silicon oxynitride layer were used as charge trapper in this investigation on the effect of the internal field inside the waveguide. Compared to waveguides without the trapping layer, experimental results showed that the induced linear electro-optic (EO) coefficient increases about 20% after poling, suggesting strongly that the internal field is relatively enhanced, and showed it is a promising means for improving nonlinearity by poling in waveguides.

  1. Investigation of Bioglass-Electrode Interfaces after Thermal Poling

    OpenAIRE

    Mariappan, C. R.; Roling, B.

    2007-01-01

    Electrical and electrochemical processes in a bioactive soda-lime phosphosilicate glasses and in a bioabsorbable soda-lime phosphate glass during thermal poling were studied by means of thermally stimulated depolarization current measurements, ac impedance spectroscopy, and SEM/EDX analyses. The thermal poling was done by sputtering thin Pt electrode films onto the faces of the glass samples and by applying voltages up to 1 kV to the electrodes at temperatures up to 513 K. The poling leads to...

  2. Rotor pole refurbishment for hydrogenerators : insulation problems and solutions

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, R.R.; Rux, L. [U.S. Army Corps of Engineers, Hydroelectric Design Centre (United States)

    2005-07-01

    Three of the 6 hydroelectric generators at the Corps of Engineers' Lower Granite Powerhouse were recently scheduled for refurbishment after 30 years of operation. Physical inspection and electrical tests of Unit 1 revealed serious problems with the field ground and turn insulation, amortisseur winding, connection and rotor rim. National Electric Coil (NEC) was contracted to reinsulate the rotor poles. The rotor field poles were removed from the rotor and shipped to a repair facility for refurbishment. A visual inspection revealed that all the poll bodies had a distinct bow, center to end, on the pole mounting surface. The deflection was as high as 0.106 inch which raised concerns about how this condition may affect the ability to properly insulate or re-seat the poles. Details of the rotor pole and field winding evaluation were presented along with the problems encountered and the measures taken to successfully refurbish the rotor poles and field winding. The following 4 options were outlined for correcting the problem of bowed rotor poles: (1) flattening the poles with a hydraulic press, (2) placing the pole in a rigid fixture with heat treatment, (3) reinstalling 4 of the poles bodies with the worst bow to see if they could be seated properly in their respective slots, and (4) machine the contact surfaces of the pole body and dovetail to the required flatness. A variation of the third option was implemented. The steps taken to resolve the issue of bowed rotor pole repair proved satisfactory for both the Government and the NEC. 6 figs.

  3. Generation of Optimal Trajectories for Earth Hybrid Pole Sitters

    OpenAIRE

    Ceriotti, Matteo; McInnes, Colin R.

    2011-01-01

    A pole-sitter orbit is a closed path that is constantly above one of the Earth’s poles by means of continuous low thrust. This work proposes to hybridize solar sail propulsion and solar electric propulsion on the same spacecraft to enable such a pole-sitter orbit. Locally optimal control laws are found with a semianalytical inverse method, starting from a trajectory that satisfies the pole-sitter condition in the sun–Earth circular restricted three-body problem. These solutions ar...

  4. Performance of new generation pole light

    International Nuclear Information System (INIS)

    This paper describes the design and implementation of a standalone photovoltaic power supply which caters for garden lighting scheme. New Generation Pole Light (NGPL) consists of three parts which are light dependent resistor (LDR) and pyroelectric infrared (PIR) sensors, microcontroller and light emitting diode (LED) and finally, solar charging system. During the night, LED is switched on with two operating modes which are ultra-bright lighting for a predetermine period (when human presence is detected) and dim lighting. Meanwhile, LED is switched off at day time and solar charging system will recover the capacity of discharged battery. NGPL provides portable, sustainable, environmental friendly and requires minimal maintenance for outdoor lighting scheme for both urban and rural areas.

  5. Performance of new generation pole light

    Science.gov (United States)

    Foo, K. C.; Karunanithi, S.; Thio, G.

    2013-06-01

    This paper describes the design and implementation of a standalone photovoltaic power supply which caters for garden lighting scheme. New Generation Pole Light (NGPL) consists of three parts which are light dependent resistor (LDR) and pyroelectric infrared (PIR) sensors, microcontroller and light emitting diode (LED) and finally, solar charging system. During the night, LED is switched on with two operating modes which are ultra-bright lighting for a predetermine period (when human presence is detected) and dim lighting. Meanwhile, LED is switched off at day time and solar charging system will recover the capacity of discharged battery. NGPL provides portable, sustainable, environmental friendly and requires minimal maintenance for outdoor lighting scheme for both urban and rural areas.

  6. Evolução conceitual de professores sobre o movimento diário da esfera celeste Conceptual evolution of teachers about the daily motion of the celestial sphere

    Directory of Open Access Journals (Sweden)

    Paulo Sergio Bretones

    2011-01-01

    Full Text Available Este é um estudo sobre a elaboração do conceito de movimento diário da esfera celeste por um grupo de professores de Ciências e Geografia de 5ª a 8ª séries, participantes de um curso de Astronomia. Os resultados baseiam-se, sobretudo, na análise de suas respostas às perguntas das avaliações e em registros de aulas do curso. Discutem-se: a relação entre as respostas dos participantes, seus relatos sobre suas observações, e o desenvolvimento de conteúdos referentes ao movimento de constelações. Apresentam-se as elaborações de sequências da evolução conceitual do grupo e sua relação com a prática e a teoria trabalhadas no curso. Tais elaborações revelam os princípios relacionados à observação do céu: relação da altura do polo celeste com a latitude geográfica, obliquidade, continuidade do movimento, circularidade, tridimensionalidade e ciclicidade. O estudo sugere que esses princípios, usados como guias heurísticos, seriam úteis para o ensino da observação do céu.This work presents a study about the concept formation of the daily motion of the celestial sphere by a group of middle school teachers participants of an Astronomy course. The results are based on the analyses of the answers of these teachers for the questions made in the check tests and the records from the classes of the course. It is studied the relation between the answers, the accounts of the sky observations by the participants and the development of the contents about the daily motion of the celestial sphere. The elaborations of sequences of the verified conceptual evolution by the group and its relation with the theory develop in the course are presented. After a closer look at the elaborations of the participants, some principles were revealed: the elevation of the celestial pole to geographic latitude, obliquity, continuity of motion, circularity, tri-dimensionality and cyclicity. The study suggests that these principles shoud be used

  7. Secondary electron emission yield on poled silica based thick films

    DEFF Research Database (Denmark)

    Braga, D.; Poumellec, B.; Cannas, V.;

    2004-01-01

    Studies on the distribution of the electric field produced by a thermal poling process in a layer of Ge-doped silica on silicon substrate, by using secondary electron emission yield (SEEY) measurements () are presented. Comparing 0 between poled and unpoled areas, the SEEY at the origin of electr...

  8. pbx is required for pole and eye regeneration in planarians.

    Science.gov (United States)

    Chen, Chun-Chieh G; Wang, Irving E; Reddien, Peter W

    2013-02-01

    Planarian regeneration involves regionalized gene expression that specifies the body plan. After amputation, planarians are capable of regenerating new anterior and posterior poles, as well as tissues polarized along the anterior-posterior, dorsal-ventral and medial-lateral axes. Wnt and several Hox genes are expressed at the posterior pole, whereas Wnt inhibitory genes, Fgf inhibitory genes, and prep, which encodes a TALE-family homeodomain protein, are expressed at the anterior pole. We found that Smed-pbx (pbx for short), which encodes a second planarian TALE-family homeodomain transcription factor, is required for restored expression of these genes at anterior and posterior poles during regeneration. Moreover, pbx(RNAi) animals gradually lose pole gene expression during homeostasis. By contrast, pbx was not required for initial anterior-posterior polarized responses to wounds, indicating that pbx is required after wound responses for development and maintenance of poles during regeneration and homeostatic tissue turnover. Independently of the requirement for pbx in pole regeneration, pbx is required for eye precursor formation and, consequently, eye regeneration and eye replacement in homeostasis. Together, these data indicate that pbx promotes pole formation of body axes and formation of regenerative progenitors for eyes. PMID:23318641

  9. Three Phase Soft Commutation Auxilary Resonant Pole Inverter

    Directory of Open Access Journals (Sweden)

    Vaclav Sladecek

    2006-01-01

    Full Text Available This paper covers the circuit modification of the power part of the inverter with auxiliary resonant poles utilising configuration of switches realised with routinely produced IGBT modules. Covered is also the control optimisation which goal is the minimisation of switching of the auxiliary resonant pole. Presented results were gained on a prototype of an inverter laboratory sample.

  10. Signature of the celestial spheres discovering order in the solar system

    CERN Document Server

    Warm, Harmut

    2010-01-01

    "A milestone in modern research on the the harmony of the spheres." - Novalis magazine "This book reignites the debate on the harmony of the spheres." - Das Goetheanum Is the solar system ordered, or is it simply the result of random and chaotic accidents? This book takes us on a powerful and compelling journey of discovery, revealing the celestial spheres' astonishingly complex patterns. The movements of the planets are found to correspond accurately with simple geometric figures and musical intervals, pointing to an exciting new perspective on the ancient idea of a "harmony of the spheres". Hartmut Warm's detailed presentation incorporates the distances, velocities and periods of conjunction of the planets, as well as the rotations of the Sun, Moon and Venus. Numerous graphics - including colour plates - illustrate the extraordinary beauty of the geometrical forms that result when the movements of several planets are viewed in relation to one another. In addition, the author describes and analyses the conce...

  11. On the implications of the Galactic aberration in proper motions for celestial reference frame

    CERN Document Server

    Malkin, Zinovy

    2014-01-01

    During the last years, much attention has been paid to the astrometric implications of the galactic aberration in proper motions (GA). This effect causes systematic errors in astrometric measurements at a microarcsecond level. Some authors consider it so serious that it requires redefinition of the celestial reference system (CRF). We argue that such attention to the GA is too much exaggerated. It is just a small astrometric correction that must be taken into account during highly accurate astrometric and geodetic data processing. The accuracy of this correction depends on accuracy of the Galactic rotation parameters and, for most application, on the accuracy of the rotation matrix between Galactic and equatorial systems. Our analysis has shown that our today knowledge of these two factors is sufficient to compute the GA correction with accuracy of better than 10%. The remaining effect at a level of few tenths microarcsecond/yr is negligible nowadays. Another consequence of introducing the GA correction is ne...

  12. The Lens-Thirring effect in the anomalistic period of celestial bodies

    CERN Document Server

    Haranas, Ioannis; Gkigkitzis, Ioannis

    2013-01-01

    In the weak field and slow motion approximation, the general relativistic field equations are linearized, resembling those of the electromagnetic theory. In a way analogous to that of a moving charge generating a magnetic field, a mass energy current can produce a gravitomagnetic field. In this contribution, the motion of a secondary celestial body is studied under the influence of the gravitomagnetic force generated by a spherical primary. More specifically, two equations are derived to approximate the periastron time rate of change and its total variation over one revolution (i.e., the difference between the anomalistic period and the Keplerian period). Kinematically, this influence results to an apsidal motion. The aforementioned quantities are numerically estimated for Mercury, the companion star of the pulsar PSR 1913 plus 16, the companion planet of the star HD 80606 and the artificial Earth satellite GRACE A. The case of the artificial Earth satellite GRACE A is also considered, but the results present...

  13. GRAIL gravity field determination using the Celestial Mechanics Approach - status report

    Science.gov (United States)

    Bertone, S.; Arnold, D.; Jäggi, A.; Beutler, G.; Mervart, L.

    2015-10-01

    The NASA mission GRAIL (Gravity Recovery And Interior Laboratory [1]) inherits its concept from the GRACE (Gravity Recovery And Climate Experiment)mission to determine the gravity field of the Moon. The use of inter-satellite Ka-band range-rate (KBRR) observations enables data aquisition even when the spacecraft are not tracked from the Earth [2]. The data allows for a highly accurate estimation of the lunar gravity field on both sides of the Moon, which is crucial to improve the understanding of its internal structure and thermal evolution. In this presentation we dis- cuss our latest GRAIL-based lunar gravity fields generated with the Celestial Mechanics Approach using the Bernese Software.

  14. On the impact of correlation information on the orientation parameters between celestial reference frame realizations

    CERN Document Server

    Sokolova, Yulia

    2014-01-01

    In this study, we compared results of determination of the orientation angles between celestial reference frames realized by radio source position catalogues using three methods of accounting for correlation information: using the position errors only, using additionally the correlations be-tween the right ascension and declination (RA/DE correlations) reported in radio source position catalogues published in the IERS format, and using the full covariance matrix. The computations were performed with nine catalogues computed at eight analysis centres. Our analysis has shown that using the RA/DE correlations only slightly influences the computed rotational angles, whereas using the full correlation matrices leads to substantial change in the orientation parameters be-tween the compared catalogues.

  15. SAS-2 observations of celestial diffuse gamma radiation above 30 MeV

    Science.gov (United States)

    Thompson, D. J.; Fichtel, C. E.; Kniffen, D. A.; Hartman, R. C.

    1974-01-01

    The small astronomy satellite, SAS-2, used a 32-deck magnetic core digitized spark chamber to study gamma rays with energies above 30 MeV. Data for four regions of the sky away from the galactic plane were analyzed. These regions show a finite, diffuse flux of gamma rays with a steep energy spectrum, and the flux is uniform over all the regions. Represented by a power law, the differential energy spectrum shows an index of 2.5 + or - 0.4. The steep SAS-2 spectrum and the lower energy data are reasonably consistent with a neutral pion gamma-ray spectrum which was red-shifted (such as that proposed by some cosmological theories). It is concluded that the diffuse celestial gamma ray spectrum observed presents the possibility of cosmological studies and possible evidence for a residual cosmic ray density, and supports the galactic superclusters of matter and antimatter remaining from baryon-symmetric big bang.

  16. Interaction between celestial and terrestrial reference frames and some considerations for the next VLBI-based ICRF

    CERN Document Server

    Malkin, Zinovy; Ma, Chopo; Lambert, Sebastien

    2014-01-01

    In this paper we outline several problems related to the realization of the international celestial and terrestrial reference frames ICRF and ITRF at the millimeter level of accuracy, with emphasis on ICRF issues. The main topics considered are: analysis of the current status of the ICRF, mutual impact of ICRF and ITRF, and some considerations for future ICRF realizations.

  17. International Celestial Reference Frame (ICRF): mantenimiento y extensión

    Science.gov (United States)

    Ma, C.; Arias, E. F.; Eubanks, T.; Fey, A. L.; Gontier, A.-M.; Jacobs, C. S.; Sovers, O. J.; Archinal, B. A.; Charlot, P.

    A partir de enero de 1998 el sistema de referencia celeste convencional está representado por el International Celestial Reference System (ICRS) y materializado a través de las coordenadas VLBI del conjunto de radiofuentes extragalácticas que conforman el International Celestial Reference Frame (ICRF). La primera realización del ICRF, fue elaborada en 1995 por un grupo de expertos designado por la IAU, la que encomendó al International Earth Rotation Service el mantenimiento del ICRS, del ICRF y del vínculo con marcos de referencia en otras frecuencias. Una primera extensión del ICRF se realizó entre abril y junio de 1999, con el objetivo primario de proveer posiciones de radiofuentes extragalácticas observadas a partir de julio de 1995 y de mejorar las posiciones de las fuentes ``candidatas" con la inclusión de observaciones adicionales. Objetivos secundarios fueron monitorear a las radiofuentes para verificar que siguen siendo adecuadas para realizar al ICRF y mejorar las técnicas de análisis de datos. Como resultado del nuevo análisis se obtuvo una solución a partir de la cual se construyó la primera extensión del ICRF, denominada ICRF - Ext.1. Ella representa al ICRS, sus fuentes de definición se mantienen con las mismas posiciones y errores que en la primera realización del ICRF; las demás radiofuentes tienen coordenadas mejor determinadas que en ICRF; el marco de referencia se densificó con el agregado de 59 nuevas radiofuentes.

  18. Changes in performance and poling kinetics during cross-country sprint skiing competition using the double-poling technique.

    Science.gov (United States)

    Mikkola, Jussi; Laaksonen, Marko S; Holmberg, Hans-Christer; Nummela, Ari; Linnamo, Vesa

    2013-11-01

    In this study, changes in skiing performance and poling kinetics during a simulated cross-country sprint skiing competition were investigated. Twelve elite male cross-country skiers performed simulated sprint competition (4 x 1,150 m heat with 20 min recovery between the heats) using the double-poling technique. Vertical and horizontal pole forces and cycle characteristics were measured using a force plate system (20-m long) during the starting spurt, racing speed, and finishing spurt of each heat. Moreover, heat and 20-m phase velocities were determined. Vertical and horizontal pole impulses as well as mean cycle length were calculated. The velocities of heats decreased by 2.7 +/- 1.7% (p = 0.003) over the simulated competition. The 20-m spurting velocity decreased by 16 +/- 5% (p < 0.002) and poling time increased by 18 +/- 9% (p < 0.003) in spurt phases within heats. Vertical and horizontal poling impulses did not change significantly during the simulation; however, the mean forces decreased (p < 0.039) (vertical by 24 +/- 11% and horizontal by 20 +/- 10%) within heats but not between the heats. Decreased heat velocities over the simulated sprint and spurting velocities within heats indicated fatigue among the skiers. Fatigue was also manifested by decreased pole force production and increased poling time.

  19. Rotor Pole Pitch Factor Influence on the Operation Parameters of a 9/10 Pole Permanent Magnet Synchronous Machine

    Directory of Open Access Journals (Sweden)

    Lazăr Florin

    2014-09-01

    Full Text Available The present paper is aimed to determine the pole pitch factor influence on the operating parameters for the considered structure. Transient analysis is used to obtain the results for each of the studied pole pitch factor. The results concern the cogging torque values, the back EMF, medium torque and torque ripple values.

  20. GUIDELESS SPATIAL COORDINATE MEASUREMENT TECHNOLOGY BASED ON CODING POLE

    Institute of Scientific and Technical Information of China (English)

    ZHAO Min; QIU Zongming; QU Jiamin; LIU Hongzhao

    2008-01-01

    A new method of guideless spatial coordinate measurement technology based on coding pole and vision measurement is proposed. Unequal spacing of bar code is adopted to pole, so that the code combination of pole image in measuring field is unique. Holographic characteristics of numeric coding pole are adopted to obtain pole pose and pole probe position by any section of bar code on the pole. Spatial coordinates of measuring points can be obtained by coordinate transform. The contradiction between high resolution and large visual field of image sensor is resolved, thereby providing a new concept for surface shape measurement of large objects with high precision. The measurement principles of the system are expounded and mathematic model is established. The measurement equation is evaluated by simulation experiments and the measurement precision is analyzed. Theoretical analysis and simulation experiments prove that this system is characterized by simple structure and wide measurement range. Therefore it can be used in the 3-dimentional coordinate measurement of large objects.

  1. Research on the Distribution and Content of Water Ice in Lunar Pole Regions Using Clementine UVVI S Data

    Institute of Scientific and Technical Information of China (English)

    Zhiguo Meng; Shengbo Chen; Peng Lu; Zijun Wang; Yi Lian; Chao Zhou

    2011-01-01

    Interest in the Moon started to increase at the beginning of the 21st century,and henceforth,more and more attention has been paid to the content and distribution of water ice in the lunar polar regions.The existence of water or ice in the regolith can apparently change its dielectric features.Therefore,in this article,the Dobson model is adopted and improved according to the Moon's environmental features,to construct the relationship between the volumetric water ice content and the dielectric constant.Thereafter,a lunar regolith dielectric distribution map is generated based on the improved Dobson model and the Clementine UVVIS data.The map indicates that the imaginary part of the dielectric constants in the lunar mare is much higher than that in the highlands.However,the maximum dielectric constants occur at the north- and south-pole regions,whose values are apparently bigger than those in the middle and low latitudes.Then,an abnormal map of the dielectric constant is gained if the threshold is put as 0.053 7,which is the highest value in the middle and low latitudes.The statistical results indicate that the number of abnormal pixels is 110 596,and the average is about 0.057 9.Assuming that the mean dielectric constant in the lunar mare is the normal dielectric constant at the south and north poles and ε1=11.58+i0.057 9 is the abnormal one,the volumetric water ice content can be evaluated using the advanced Dobson model.The results show that the average volumetric water ice content is about 1.64%,and the total area is about 25 294 km2,where 10 956 km2 belongs to the north pole and the rest is in the south pole.

  2. Domain wall width of lithium niobate poled during growth

    CERN Document Server

    Brooks, R; Hole, D E; Callejo, D; Bermudez, V; Diéguez, E

    2003-01-01

    Good quality crystals of periodically poled lithium niobate can be generated directly during growth. However, the temperature gradients at the zone boundaries define the width of the regions where the polarity is reversed. Hence, the region influenced the domain transition may be a significant fraction of the overall poling period for material poled during growth. Evidence for the scale of this feature is reported both by chemical etching and by the less common method of ion beam luminescence and the 'domain wall' width approximately 1 mu m for these analyses. The influence of the reversal region may differ for alternative techniques but the relevance to device design for second harmonic generation is noted.

  3. Status of GRAIL Gravity Field Determination Using the Celestial Mechanics Approach

    Science.gov (United States)

    Arnold, Daniel; Beutler, Gerhard; Jäggi, Adrian; Bock, Heike; Mervart, Leos; Meyer, Ulrich; Bertone, Stefano

    To determine the gravity field of the Moon, the NASA mission GRAIL (Gravity Recovery And Interior Laboratory) inherits its concept from the Earth orbiting GRACE (Gravity Recovery and Climate Experiment) mission. The use of ultra-precise inter-satellite Ka-band ranging observations enables data acquisition even when the spacecraft are not tracked from the Earth. The data allows for a highly accurate estimation of the lunar gravity field with unprecedented resolution on both sides of the Moon, which is crucial to improve the understanding of its internal structure and thermal evolution. In this presentation we discuss GRAIL-based lunar gravity fields generated with the Celestial Mechanics Approach. Ka-band range-rate (KBRR) observations and position data (GNI1B products) are used to solve for the lunar gravity field parameters in a generalized orbit determination problem. Apart from normalized spherical harmonic coefficients up to degrees n≤ 200, also arc- and satellite-specific parameters, like initial state vectors and pseudo-stochastic pulses, are set up as common parameters for all measurement types. The latter shall compensate for imperfect models of non-gravitational accelerations, e.g., caused by solar radiation pressure. In addition, especially for the data of the primary mission phase, it is essential to estimate time bias parameters for the KBRR observations. We compare our results from the nominal mission phase with the official Level 2 gravity field models first released in October 2013. Our results demonstrate that the lunar gravity field can be recovered with a high quality by adapting the Celestial Mechanics Approach, even when using pre-GRAIL or pre-SELENE gravity field models as a priori fields and when replacing sophisticated models of non-gravitational accelerations by appropriately spaced and constrained pseudo-stochastic pulses. Yet, the usage of preprocessed position data as pseudo observations is not fully satisfying and is potentially

  4. TOUGHENING OF FERROELECTRICS BY THE OUT-OF-PLANE POLING

    Institute of Scientific and Technical Information of China (English)

    杨卫; 方菲

    2003-01-01

    Subjected to the prior out-of-plane poling, the ferroelectrics can be toughened considerably. The present paper describes the variation of the stress intensity factor (SIF) by 90° switching in ferroelectrics. The analysis is carried out for the combined mechanical and electrical loading, with simple relations obtained for the case of the purely electrical loading. The out-of-plane poling is found to raise the SIF for the crack initiation, but appreciably reduces the SIF for the crack growth in a steady state. More stable fracture resistance curves can be achieved by the out-of-plane poling. This prediction is supported quantitatively by the testing data of SENB specimens of PZT-5 samples, when the toughening effects of polings in three orthogonal directions are compared.

  5. CCD-Photometry and Pole Coordinates for Eight Asteroids

    Science.gov (United States)

    Shevchenko, V. G.; Tungalag, N.; Chiorny, V. G.; Gaftonyuk, N. M.; Krugly, Y. N.; Harris, A. W.; Young, J. W.

    2012-05-01

    The long time photometric observations were carried out for eight asteroids: (122) Gerda, (153) Hilda, (190) Ismene, (221) Eos, (411) Xanthe, (679) Pax, (700) Auravictrix, (787) Moskva. For the observed asteroids were determined new pole coordinates.

  6. China Becomes Growth Pole of Global Milk Industry

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ It was recently learnt from China Association of Milk Industry, the developing trend of the global milk industry indicates that,China has become the growth pole of the future development of the global milk industry.

  7. Asymmetric spindle pole formation in CPAP-depleted mitotic cells.

    Science.gov (United States)

    Lee, Miseon; Chang, Jaerak; Chang, Sunghoe; Lee, Kyung S; Rhee, Kunsoo

    2014-02-21

    CPAP is an essential component for centriole formation. Here, we report that CPAP is also critical for symmetric spindle pole formation during mitosis. We observed that pericentriolar material between the mitotic spindle poles were asymmetrically distributed in CPAP-depleted cells even with intact numbers of centrioles. The length of procentrioles was slightly reduced by CPAP depletion, but the length of mother centrioles was not affected. Surprisingly, the young mother centrioles of the CPAP-depleted cells are not fully matured, as evidenced by the absence of distal and subdistal appendage proteins. We propose that the selective absence of centriolar appendages at the young mother centrioles may be responsible for asymmetric spindle pole formation in CPAP-depleted cells. Our results suggest that the neural stem cells with CPAP mutations might form asymmetric spindle poles, which results in premature initiation of differentiation.

  8. Pole Term and Gauge Invariance in Deep Inelastic Scattering

    CERN Document Server

    Batiz, Z; Batiz, Zoltan; Gross, Franz

    1998-01-01

    In this paper we reconcile two contradictory statements about deep inelastic scattering (DIS) in manifestly covariant theories: (i) the scattering must be gauge invariant, even in the deep inelastic limit, and (ii) the pole term (which is not gauge invariant in a covariant theory) dominates the scattering amplitude in the deep inelastic limit. An ``intermediate'' answer is found to be true. We show that, at all energies, the gauge dependent part of the pole term cancels the gauge dependent part of the rescattering term, so that both the pole and rescattering terms can be separately redefined in a gauge invariant fashion. The resulting, redefined pole term is then shown to dominate the scattering in the deep inelastic limit. Details are worked out for a simple example in 1+1 dimensions.

  9. Periodic, Quasi-Periodic and Chaotic Motions in Celestial Mechanics: Theory and Applications Selected papers from the Fourth Meeting on Celestial Mechanics, CELMEC IV San Martino al Cimino (Italy), 11–16 September 2005

    CERN Document Server

    Celletti, A

    2006-01-01

    The book provides the most recent advances of Celestial Mechanics, as provided by high-level scientists working in this field. It covers theoretical investigations as well as applications to concrete problems. Outstanding review papers are included in the book and they introduce the reader to leading subjects, like the variational approaches to find periodic orbits, the stability theory of the N-body problem, the spin-orbit resonances and chaotic dynamics, the space debris polluting the circumterrestrial space.

  10. Diffraction Profile Pole Figures Measured with a Position Sensitive Detector

    OpenAIRE

    Wcislak, L.; Bunge, H.J.

    1996-01-01

    Pole figures in the classical sense are defined by the integral intensities of Bragg reflections. The conventional technique of pole figure measurement uses a single detector (usually a scintillation counter) with a wide receiving slit where the integral intensity of a given Bragg reflection is obtained directly. The usage of a position sensitive detector instead of a single detector allows to measure whole diffraction profiles simultaneously. Integral intensities of the diffraction peaks can...

  11. Systems design of a hybrid sail pole-sitter

    OpenAIRE

    Ceriotti, Matteo; McInnes, Colin R.

    2011-01-01

    This paper presents the preliminary systems design of a pole-sitter. This is a spacecraft that hovers over an Earth pole, creating a platform for full hemispheric observation of the polar regions, as well as direct-link telecommunications. To provide the necessary thrust, a hybrid propulsion system combines a solar sail with a more mature solar electric propulsion (SEP) thruster. Previous work by the authors showed that the combination of the two allows lower propellant mass fractions, at the...

  12. Weakly polarization dependent electro-optic effect in poled silica

    DEFF Research Database (Denmark)

    Arentoft, Jesper; Pedersen, K.; Bozhevolnyi, Sergey I.;

    1999-01-01

    A ratio between c(2)33 and c(2)31 less than 3 is observed in measurements of the linear electro-optic effect and second-harmonic generation of poled silica.......A ratio between c(2)33 and c(2)31 less than 3 is observed in measurements of the linear electro-optic effect and second-harmonic generation of poled silica....

  13. Poling-assisted bleaching of metal-doped nanocomposite glass

    OpenAIRE

    Deparis, O.; Kazansky, P. G.; Abdolvand, A.; Podlipensky, A.; Seifert, G.; Graener, H

    2004-01-01

    Thermal poling of soda-lime glass which was doped with spherical or ellipsoidal silver nanoparticles has revealed what we believe to be a phenomenon of general interest in the physics of nanocomposite materials: The field-assisted dissolution of metal nanoparticles embedded in glass. Macroscopically, this phenomenon manifested itself as poling-assisted bleaching of the glass in the sense that the glass became more (or even completely) transparent under the anode. The phenomenon is physically ...

  14. Absolute multi-pole encoder with a simple structure based on an improved gray code to enhance the resolution

    Institute of Scientific and Technical Information of China (English)

    LIU Yong; HAO Shuang-hui; HAO Ming-hui

    2009-01-01

    We developed a novel absolute multi-pole encoder structure to improve the resolution of the multi-pole encoder, realize absolute output and reduce the manufacturing cost of the encoder. The structure includes two ring alnicos defined as index track and sub-division track, respectively. The index track is magnetized based on the improved gray code, with linear halls placed around the track evenly. The outputs of linear halls show the region the rotor belongs to. The sub-division track is magnetized to N-S-N-S (north-south-north-south), and the number of N-S pole pairs is determined by the index track. Three linear hall sensors with an air-gap of 2 mm are used to translate the magnetic filed to voltage signals. The relative offset in a single N-S is obtained through look-up. The magnetic encoder is calibrated using a higher-resolution incremental optical encoder. The pulse output from the optical encoder and hall signals from the magnetic encoder are sampled at the same time and transmitted to a computer, and the relation between them is calculated, and stored in the FLASH of MCU (micro controller unit) for look-up. In the working state, the absolute angle is derived by looking-up with hall signals. The structure is simple and the manufacturing cost is very low and suitable for mass production.

  15. Gamma Oscillations in the Temporal Pole in Response to Eyes.

    Science.gov (United States)

    Sato, Wataru; Kochiyama, Takanori; Uono, Shota; Matsuda, Kazumi; Usui, Keiko; Usui, Naotaka; Inoue, Yushi; Toichi, Motomi

    2016-01-01

    The eyes of an individual act as an indispensable communication medium during human social interactions. Functional neuroimaging studies have revealed that several brain regions are activated in response to eyes and eye gaze direction changes. However, it remains unclear whether the temporal pole is one of these regions. Furthermore, if the temporal pole is activated by these stimuli, the timing and manner in which it is activated also remain unclear. To investigate these issues, we analyzed intracranial electroencephalographic data from the temporal pole that were obtained during the presentation of eyes and mosaics in averted or straight directions and their directional changes. Time-frequency statistical parametric mapping analyses revealed that the bilateral temporal poles exhibited greater gamma-band activation beginning at 215 ms in response to eyes compared with mosaics, irrespective of the direction. Additionally, the right temporal pole showed greater gamma-band activation beginning at 197 ms in response to directional changes of the eyes compared with mosaics. These results suggest that gamma-band oscillations in the temporal pole were involved in the processing of the presence of eyes and changes in eye gaze direction at a relatively late temporal stage compared with the posterior cortices. PMID:27571204

  16. International Youth Conference on the Poles

    Science.gov (United States)

    Church, A. K.; Kuhn, T. S.; Baeseman, J.; Garmulewicz, A.; Raymond, M.; Salmon, R.

    2006-12-01

    The International Polar Year (IPY) is an international effort, involving more than 50 countries, to focus research in both the sciences and social sciences on the world's Polar Regions. In order to secure youth involvement in the IPY, the Youth Steering Committee (YSC) has been formed, aiming specifically to network young polar researchers from all backgrounds enabling collaboration and to involve this group in outreach focused towards other young people. A conference targeted directly at an audience of early career researchers and international youth will be central to fulfilling these aims. The YSC has therefore developed the concept of the International Youth Conference on the Poles (IYCP). Proposed for 2008, this conference will bring together youth from a diverse set of backgrounds and nationalities to discuss the issues affecting the Polar Regions, their effects on a global scale and ways of addressing these issues. The conference will also serve to highlight ongoing IPY research, especially research being undertaken by young researchers, and provide a perennial framework for youth involvement in polar research and policies. The IYCP will run for three days in May 2008, attracting an international youth audience, as well as representatives from polar organizations, teachers, politicians, policy makers, the general public and media. The IYCP will be divided into three sections. Youth Roundtable Discussions will bring youth together to discuss issues affecting the Polar Regions and potential solutions to these. A Young Researchers Conference will provide the opportunity for young researchers working in the Polar Regions to present their work to an interdisciplinary audience. The Polar Fair will provide an interactive environment for youth to learn about the Polar Regions. The IYCP will be of great importance to the IPY because it will serve as the principle venue during the Polar Year where youth from many different disciplines, backgrounds and countries will

  17. Conference on Hamiltonian Systems and Celestial Mechanics 2014 & Workshop on Virus Dynamics and Evolution : Extended Abstracts Spring 2014

    CERN Document Server

    Cors, Josep; Llibre, Jaume; Korobeinikov, Andrei

    2015-01-01

    The two parts of the present volume contain extended conference abstracts corresponding to selected talks given by participants at the "Conference on Hamiltonian Systems and Celestial Mechanics 2014" (HAMSYS2014) (15 abstracts) and at the "Workshop on Virus Dynamics and Evolution" (12 abstracts), both held at the Centre de Recerca Matemàtica (CRM) in Barcelona from June 2nd to 6th, 2014, and from June 23th to 27th, 2014, respectively. Most of them are brief articles, containing preliminary presentations of new results not yet published in regular research journals. The articles are the result of a direct collaboration between active researchers in the area after working in a dynamic and productive atmosphere. The first part is about Central Configurations, Periodic Orbits and Hamiltonian Systems with applications to Celestial Mechanics – a very modern and active field of research. The second part is dedicated to mathematical methods applied to viral dynamics and evolution. Mathematical modelling of biologi...

  18. Bias Estimations for Ill-posed Problem of Celestial Positioning Using the Sun and Precision Analysis

    Directory of Open Access Journals (Sweden)

    ZHAN Yinhu

    2016-08-01

    Full Text Available Lunar/Mars rovers own sun sensors for navigation, however, long-time tracking for the sun impacts on the real-time activity of navigation. Absolute positioning method by observing the sun with a super short tracking period such as 1 or 2 minutes is researched in this paper. Linear least squares model of altitude positioning method is deduced, and the ill-posed problem of celestial positioning using the sun is brought out for the first time. Singular value decomposition method is used to diagnose the ill-posed problem, and different bias estimations are employed and compared by simulative calculations. Results of the calculations indicate the superiority of bias estimations which can effectively improve initial values. However, bias estimations are greatly impacted by initial values, because the initial values converge at a line which passes by the real value and is vertical relative to the orientation of the sun. The research of this paper is of some value to application.

  19. Quantum Celestial Mechanics: Large-scale Gravitational Quantization States in Galaxies and the Universe

    Science.gov (United States)

    Preston, Howard G.; Potter, Franklin

    2006-03-01

    We report a new theory of celestial mechanics for gravitationally bound systems based upon a gravitational wave equation derived from the general relativistic Hamilton-Jacobi equation. The single ad hoc assumption is that the large-scale physical properties depend only on the ratio of the bound system's total angular momentum to its total mass. The theory predicts quantization states for the Solar System and for galaxies. The galactic quantization determines the energy and angular momentum eigenstates without requiring dark matter, and predicts expressions for the galactic disk rotation velocity, the baryonic Tully-Fisher relation, the MOND acceleration parameter, the large-angle gravitational lensing, and the shape, stability and number of arms in spiral galaxies. Applied to the universe, the theory has a repulsive effective gravitational potential that predicts a new Hubble relation and explains the observed apparent acceleration of distant supernovae with the matter/energy density of the universe at the critical density with only about 5% matter content. We suggest a laboratory experiment with a torsion bar near a rotating mass. This theory is not quantum gravity.

  20. Non-parametric PSF estimation from celestial transit solar images using blind deconvolution

    CERN Document Server

    Gonzalez, Adriana; Jacques, Laurent

    2016-01-01

    Context: Characterization of instrumental effects in astronomical imaging is important in order to extract accurate physical information from the observations. Optics are never perfect and the non-ideal path through the telescope is usually represented by the convolution of an ideal image with a Point Spread Function (PSF). Other sources of noise (read-out, Photon) also contaminate the image acquisition process. The problem of estimating both the PSF filter and a denoised image is called blind deconvolution and is ill-posed. Aims: We propose a blind deconvolution scheme that relies on image regularization. Contrarily to most methods presented in the literature, it does not assume a parametric model of the PSF and can thus be applied to any telescope. Methods: Our scheme uses a wavelet analysis image prior model and weak assumptions on the PSF filter's response. We use the observations from a celestial body transit where such object can be assumed to be a black disk. Such constraints limits the interchangeabil...

  1. Edward Burne-Jones’ The Days of Creation: A Celestial Utopia

    Directory of Open Access Journals (Sweden)

    Liana De Girolami Cheney

    2014-09-01

    Full Text Available Edward Burne-Jones’ cycle of The Days of Creation of 1870-66(Fogg Art Museum, Harvard University Museums, Cambridge, MA was highly praised and elegantly described by Oscar Wilde: “The picture is divided into six compartments, each representing a day in the Creation of the World, under the symbol of an angel holding a crystal globe, within which is shown the work of a day.” This essay examines how Burne-Jones visualized an unusual celestial creation where angels holding magical spheres unveil the divine manifestation for the creation of a terrestrial realm. His The Days of Creation is an aesthetic culmination of the artistic power of invention, imitation and creation of beauty. Burne-Jones borrows the divine concept of world creation to formulate his own artist creation. Selecting God’s week of creation, he empowers a daily angel to manifest the beauty and power of divine creation. Ultimately, Burne-Jones creates a cosmic utopia, a mythical heavenly and natural realm, where angels design a world of beauty to be emulated not only by the artist, but also by most of all by the viewer.

  2. Dual-EKF-Based Real-Time Celestial Navigation for Lunar Rover

    Directory of Open Access Journals (Sweden)

    Li Xie

    2012-01-01

    Full Text Available A key requirement of lunar rover autonomous navigation is to acquire state information accurately in real-time during its motion and set up a gradual parameter-based nonlinear kinematics model for the rover. In this paper, we propose a dual-extended-Kalman-filter- (dual-EKF- based real-time celestial navigation (RCN method. The proposed method considers the rover position and velocity on the lunar surface as the system parameters and establishes a constant velocity (CV model. In addition, the attitude quaternion is considered as the system state, and the quaternion differential equation is established as the state equation, which incorporates the output of angular rate gyroscope. Therefore, the measurement equation can be established with sun direction vector from the sun sensor and speed observation from the speedometer. The gyro continuous output ensures the algorithm real-time operation. Finally, we use the dual-EKF method to solve the system equations. Simulation results show that the proposed method can acquire the rover position and heading information in real time and greatly improve the navigation accuracy. Our method overcomes the disadvantage of the cumulative error in inertial navigation.

  3. Optical identifications of celestial high energy sources with the Telescopio Nazionale Galileo

    International Nuclear Information System (INIS)

    To ascertain the nature of celestial high energy sources, it is crucial to identify their optical counterparts. However, the currently available astronomical public optical databases do not provide an adequate support for a systematic high energy sources identification work. In particular, the optical limiting magnitude represents a severe limitation since the deepest flux limits reached by X-ray surveys require of course similarly deeper optical catalogs to homogeneously sample the available parameter space. Nonetheless, dedicated spectroscopic campaigns are being carried out successfully with the Telescopio Nazionale Galileo (TNG), a 4-m class telescope. To set up a winning observational campaign, the first and most important step is to define a strong science case, as it will allow for selections of good targets for observations: the key is to increase the identification efficiency while keeping down the required telescope time. In this context, as the Principal Investigator, I will give an overview of the first spectroscopic campaign carried out at the TNG to identify Swift X-ray serendipitous sources, and I will show the valuable results achieved with only one night of observations. As a second example, I will review the strategy for the northern-sky classification of candidate blazars associated to unidentified Fermi γ-ray sources, and I will show the results coming from the related observational campaign at TNG I have been involved during the last two years.

  4. The effects of frequency-dependent quasar evolution on the celestial reference frame

    CERN Document Server

    Shabala, Stanislav; McCallum, Jamie; Titov, Oleg; Blanchard, Jay; Lovell, Jim; Watson, Christopher

    2013-01-01

    We examine the relationship between source position stability and astrophysical properties of radio-loud quasars making up the International Celestial Reference Frame. We construct light curves for 95 most frequently observed ICRF2 quasars at both the geodetic VLBI observing bands. Because the appearance of new quasar components corresponds to an increase in quasar flux density, these light curves allow us to probe source structure on sub-100 microarcsecond scales, much smaller than conventional VLBI imaging. Flux density monitoring also allows us to trace the evolution of quasar structure. We test how source position stability depends on three astrophysical parameters: (1) Flux density variability at X-band; (2) Time lag between S and X-band light curves; (3) Spectral index rms, defined as the variability in the ratio between S and X-band flux densities. We find that small (<0.15 years) time lags between S and X-band light curves and low (<0.10) spectral index variability are excellent indicators of po...

  5. Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Planets and Celestial Calibration Sources

    CERN Document Server

    Weiland, J L; Hill, R S; Wollack, E; Hinshaw, G; Greason, M R; Jarosik, N; Page, L; Bennett, C L; Dunkley, J; Gold, B; Halpern, M; Kogut, A; Komatsu, E; Larson, D; Limon, M; Meyer, S S; Nolta, M R; Smith, K M; Spergel, D N; Tucker, G S; Wright, E L

    2010-01-01

    We present WMAP seven-year observations of bright sources which are often used as calibrators at microwave frequencies. Ten objects are studied in five frequency bands (23 - 94 GHz): the outer planets (Mars, Jupiter, Saturn, Uranus and Neptune) and five fixed celestial sources (Cas A, Tau A, Cyg A, 3C274 and 3C58). The seven-year analysis of Jupiter provides temperatures which are within 1-sigma of the previously published WMAP five-year values, with slightly tighter constraints on variability with orbital phase, and limits (but no detections) on linear polarization. Scaling factors are provided which, when multiplied by the Wright Mars thermal model predictions at 350 micron, reproduce WMAP seasonally averaged observations of Mars within ~2%. An empirical model is described which fits brightness variations of Saturn due to geometrical effects and can be used to predict the WMAP observations to within 3%. Seven-year mean temperatures for Uranus and Neptune are also tabulated. Uncertainties in Uranus temperatu...

  6. Kepler-47 Circumbinary Planets obey Quantization of Angular Momentum per Unit Mass predicted by Quantum Celestial Mechanics (QCM

    Directory of Open Access Journals (Sweden)

    Potter F.

    2014-01-01

    Full Text Available The Kepler-47 circumbinary system has three known planets orbiting its binary star barycenter and therefore can provide a precision test of the Quantum Celestial Mechan- ics (QCM prediction of the quantization of angular momentum per unit mass in all gravitationally bound systems. Two of the planets are in the Habitable Zone (HZ, so system stability can be a primary concern. QCM may be a major contributor to the stability of this system.

  7. Multi-Planet Exosystems All Obey Orbital Angular Momentum Quantization per Unit Mass predicted by Quantum Celestial Mechanics (QCM

    Directory of Open Access Journals (Sweden)

    Potter F.

    2013-07-01

    Full Text Available Quantum celestial mechanics (QCM predicts that all orbiting bodies in gravitationally bound systems exhibit the quantization of orbital angular momentum per unit mass. I show that the 15 known multi-planet systems with four or more planets obey this QCM prediction. This angular momentum constraint could be the explanation for their orbital stability for billions of years, suggesting that viable models of the formation and evolution of gravitational systems must include QCM.

  8. Optimal pole shifting controller for interconnected power system

    International Nuclear Information System (INIS)

    Research highlights: → Mathematical model represents a power system which consists of synchronous machine connected to infinite bus through transmission line. → Power system stabilizer was designed based on optimal pole shifting controller. → The system performances was tested through load disturbances at different operating conditions. → The system performance with the proposed optimal pole shifting controller is compared with the conventional pole placement controller. → The digital simulation results indicated that the proposed controller has a superior performance. -- Abstract: Power system stabilizer based on optimal pole shifting is proposed. An approach for shifting the real parts of the open-loop poles to any desired positions while preserving the imaginary parts is presented. In each step of this approach, it is required to solve a first-order or a second-order linear matrix Lyapunov equation for shifting one real pole or two complex conjugate poles, respectively. This presented method yields a solution, which is optimal with respect to a quadratic performance index. The attractive feature of this method is that it enables solutions of the complex problem to be easily found without solving any non-linear algebraic Riccati equation. The present power system stabilizer is based on Riccati equation approach. The control law depends on finding the feedback gain matrix, and then the control signal is synthesized by multiplying the state variables of the power system with determined gain matrix. The gain matrix is calculated one time only, and it works over wide range of operating conditions. To validate the power of the proposed PSS, a linearized model of a simple power system consisted of a single synchronous machine connected to infinite bus bar through transmission line is simulated. The studied power system is subjected to various operating points and power system parameters changes.

  9. Temperature retrieval at the southern pole of the Venusian atmosphere

    Science.gov (United States)

    Garate-Lopez, Itziar; Garcia-Munoz, A.; Hueso, R.; Sanchez-Lavega, A.

    2013-10-01

    Venus’ thermal radiation spectrum is punctuated by CO2 bands of various strengths probing into different atmospheric depths. It is thus possible to invert measured spectra of thermal radiation to infer atmospheric temperature profiles. VIRTIS-M observations of Venus in the 3-5 µm range allow us to study the night time thermal structure of the planet’s upper troposphere and lower mesosphere from 50 to 105 km [1, 2]. Building a forward radiative transfer model that solves the radiative transfer equation for the atmosphere on a line-by-line basis, we confirmed that aerosol scattering must be taken into account and we studied the impact of factors such as cloud opacity, and the size, composition and vertical distribution of aerosols [3]. The cloud top altitude and aerosol scale height have a notable impact on the spectrum. However, their weighting function matrices have similar structures contributing to the degeneracy of the temperature retrieval algorithm [2]. Our retrieval code is focused on the strong 4.3µm CO2 band, which enables the determination of the thermal profile above the cloud top, and based on the algorithm proposed by Grassi et al. (2008) in their equation (2). We present temperature maps for the south pole of Venus, where a highly variable vortex is observed. We aim to combine these maps with our previously measured velocity fields from the same VIRTIS-M infrared images [4], in order to infer the potential vorticity distribution for different vortex configurations and to improve the understanding of its unpredictable character and its role in the general atmospheric circulation. Acknowledgements This work was supported by the Spanish MICIIN projects AYA2009-10701 and AYA2012-36666 with FEDER funds, by Grupos Gobierno Vasco IT-765-13 and by Universidad País Vasco UPV/EHU through program UFI11/55. IGL and AGM gratefully acknowledge ESA/RSSD for hospitality and access to ‘The Grid’ computing resources. References [1] Roos-Serote, M., et al

  10. Avoidance of a Landau pole by flat contributions in QED

    Energy Technology Data Exchange (ETDEWEB)

    Klaczynski, Lutz, E-mail: lutz.klaczynski@gmx.de [Department of Physics, Humboldt University Berlin, 12489 Berlin (Germany); Kreimer, Dirk, E-mail: kreimer@mathematik.hu-berlin.de [Alexander von Humboldt Chair in Mathematical Physics, Humboldt University, Berlin 12489 (Germany)

    2014-05-15

    We consider massless Quantum Electrodynamics in the momentum scheme and carry forward an approach based on Dyson–Schwinger equations to approximate both the β-function and the renormalized photon self-energy (Yeats, 2011). Starting from the Callan–Symanzik equation, we derive a renormalization group (RG) recursion identity which implies a non-linear ODE for the anomalous dimension and extract a sufficient but not necessary criterion for the existence of a Landau pole. This criterion implies a necessary condition for QED to have no such pole. Solving the differential equation exactly for a toy model case, we integrate the corresponding RG equation for the running coupling and find that even though the β-function entails a Landau pole it exhibits a flat contribution capable of decreasing its growth, in other cases possibly to the extent that such a pole is avoided altogether. Finally, by applying the recursion identity, we compute the photon propagator and investigate the effect of flat contributions on both spacelike and timelike photons. -- Highlights: •We present an approach to approximate both the β-function and the photon self-energy. •We find a sufficient criterion for the self-energy to entail the existence of a Landau pole. •We study non-perturbative ‘flat’ contributions that emerge within the context of our approach. •We discuss a toy model and how it is affected by flat contributions.

  11. Assessment of Pole Erosion in a Magnetically Shielded Hall Thruster

    Science.gov (United States)

    Mikellides, Ioannis G.; Ortega, Alejandro L.

    2014-01-01

    Numerical simulations of a 6-kW laboratory Hall thruster called H6 have been performed to quantify the erosion rate at the inner pole. The assessments have been made in two versions of the thruster, namely the unshielded (H6US) and magnetically shielded (H6MS) configurations. The simulations have been performed with the 2-D axisymmetric code Hall2De which employs a new multi-fluid ion algorithm to capture the presence of low-energy ions in the vicinity of the poles. It is found that the maximum computed erosion rate at the inner pole of the H6MS exceeds the measured rate of back-sputtered deposits by 4.5 times. This explains only part of the surface roughening that was observed after a 150-h wear test, which covered most of the pole area exposed to the plasma. For the majority of the pole surface the computed erosion rates are found to be below the back-sputter rate and comparable to those in the H6US which exhibited little to no sputtering in previous tests. Possible explanations for the discrepancy are discussed.

  12. ULYSSES comes full circle, before revisiting the Sun's poles

    Science.gov (United States)

    1998-04-01

    slanted orbit took Ulysses to solar latitudes greater than 70 degrees for a total of 234 days -- first in the southern hemisphere and then in the north. Also of great interest was the rapid passage from the south to the north, via the Sun's equatorial region, during which Ulysses covered 160 degrees in solar latitude in less than a year. Nine onboard experiments have gathered data continuously since launch, for international teams totalling 150 scientists. Some instruments detect the outward-blowing solar wind and its magnetic field, which create the heliosphere. Others record cosmic rays coming in from the Galaxy, which are strongly influenced by the solar wind. Ulysses picks up natural radio signals emitted by the Sun, the planets and the heliosphere itself. Innovative techniques identify alien atoms and dust particles infiltrating the heliosphere from interstellar space. Ulysses is also a key member of a network of interplanetary spacecraft making observations of enigmatic bursts of gamma rays originating in the far reaches of the Universe. New facts about the fast solar wind were among Ulysses' most fundamental discoveries. The typical solar wind emerging from the Sun's equatorial zone is variable but relatively slow, at 350-400 kilometres per second. The fast wind blows at a steady 750 kilometres per second. It comes from cool regions of the solar atmosphere called coronal holes which (when the Sun is quiet) are close to the poles and fairly small. Yet Ulysses found the fast wind fanning out to fill two-thirds of the volume of the heliosphere. The boundary between the two windstreams is unexpectedly sharp. The magnetic field of the Sun turns out to be strangely uniform at all latitudes in the heliosphere. Close to the visible surface of the Sun, the magnetic field is strongest over the poles, but this intensification disappears at Ulysses' distance. Apparently magnetic pressure in the solar wind averages out the differences in field strength. On the other hand

  13. Non-parametric PSF estimation from celestial transit solar images using blind deconvolution

    Science.gov (United States)

    González, Adriana; Delouille, Véronique; Jacques, Laurent

    2016-01-01

    Context: Characterization of instrumental effects in astronomical imaging is important in order to extract accurate physical information from the observations. The measured image in a real optical instrument is usually represented by the convolution of an ideal image with a Point Spread Function (PSF). Additionally, the image acquisition process is also contaminated by other sources of noise (read-out, photon-counting). The problem of estimating both the PSF and a denoised image is called blind deconvolution and is ill-posed. Aims: We propose a blind deconvolution scheme that relies on image regularization. Contrarily to most methods presented in the literature, our method does not assume a parametric model of the PSF and can thus be applied to any telescope. Methods: Our scheme uses a wavelet analysis prior model on the image and weak assumptions on the PSF. We use observations from a celestial transit, where the occulting body can be assumed to be a black disk. These constraints allow us to retain meaningful solutions for the filter and the image, eliminating trivial, translated, and interchanged solutions. Under an additive Gaussian noise assumption, they also enforce noise canceling and avoid reconstruction artifacts by promoting the whiteness of the residual between the blurred observations and the cleaned data. Results: Our method is applied to synthetic and experimental data. The PSF is estimated for the SECCHI/EUVI instrument using the 2007 Lunar transit, and for SDO/AIA using the 2012 Venus transit. Results show that the proposed non-parametric blind deconvolution method is able to estimate the core of the PSF with a similar quality to parametric methods proposed in the literature. We also show that, if these parametric estimations are incorporated in the acquisition model, the resulting PSF outperforms both the parametric and non-parametric methods.

  14. Latest Moon gravity field solutions from GRAIL data using the Celestial Mechanics Approach

    Science.gov (United States)

    Bertone, Stefano; Arnold, Daniel; Jäggi, Adrian; Beutler, Gerhard; Mervart, Leos; Meyer, Ulrich

    2016-04-01

    The NASA mission GRAIL inherits its concept from the GRACE mission to determine the gravity field of the Moon. The use of inter-satellite Ka-band range-rate (KBRR) observations enables data acquisition even when the spacecraft are not tracked from the Earth. The data allows for a highly accurate estimation of the lunar gravity field on both sides of the Moon, which is leading to huge improvements in our understanding of its internal structure and thermal evolution. In this presentation we discuss the latest GRAIL-based lunar gravity fields generated with the Celestial Mechanics Approach using the Bernese GNSS Software. We recently presented our solutions up to d/o 200, where KBRR observations and position data (GNI1B products) were used to solve for the lunar gravity field parameters in a generalized orbit determination problem. As a further extension of our processing, the GNI1B positions are now replaced by the original Doppler observations of the Deep Space Network (DSN) to allow for a completely independent determination of the lunar gravity field. Based on Doppler data, we perform orbit determination by solving six initial orbital elements, dynamical parameters, and stochastic parameters in daily arcs using least-squares adjustment. The pseudo-stochastic parameters are estimated to absorb deficiencies in our dynamical modeling (e.g. due to non-gravitational forces). Doppler and KBRR data are then used together with an appropriate weighting for a combined orbit determination process. We present our latest results in the orbit determination of GRAIL over the primary mission phase (PM, March-May 2012) and our first lunar gravity fields based on Doppler and KBRR observations. We compare all of our results from the PM with the most recent lunar gravity field models released by other groups, as well as their consistency with topography-induced gravity.

  15. THE ESTIMATION OF ORDERING DEGREE OF CORONA-POLED NONLINEAR OPTICAL POLYMER FILMS

    Institute of Scientific and Technical Information of China (English)

    YE Cheng; DONG Haiou; WANG Jiafu

    1992-01-01

    The investigation of electrochromic effect of corona-poled nonlinear optical polymer films is an effective method for the estimation of poling level and the selection of poling conditions. The poling electric field Ep and orientational order parameter φ, which are the important parameters to predict d33 of poled tilms, can be calculated by a simple operation from the number of red shift of charge transfer absorption band. The calculated results are in good agreement with the experimental data.

  16. Deep Extragalactic Surveys around the Ecliptic Poles with AKARI (ASTRO-F)

    CERN Document Server

    Matsuhara, H; Matsuura, S; Nakagawa, T; Kawada, M; Oyama, Y; Pearson, C P; Oyabu, S; Takagi, T; Serjeant, S; White, G J; Hanami, H; Watarai, H; Takeuchi, T T; Kodama, T; Arimoto, N; Okamura, S; Lee, H M; Pak, S; Im, M S; Lee, M G; Kim, W; Jeong, W S; Imai, K; Fujishiro, N; Shirahata, M; Suzuki, T; Ihara, C; Sakon, I; Matsuhara, Hideo; Wada, Takehiko; Matsuura, Shuji; Nakagawa, Takao; Kawada, Mitsunobu; Oyama, Youichi; Pearson, Chris P.; Oyabu, Shinki; Takagi, Toshinobu; Serjeant, Stephen; White, Glenn J.; Hanami, Hitoshi; Watarai, Hidenori; Takeuchi, Tsutomu T.; Kodama, Tadayuki; Arimoto, Nobuo; Okamura, Sadanori; Lee, Hyung Mok; Pak, Soojong; Im, Myung Shin; Lee, Myung Gyoon; Kim, Woojung; Jeong, Woong Seob; Imai, Koji; Fujishiro, Naofumi; Shirahata, Mai; Suzuki, Toyoaki; Ihara, Chiaki; Sakon, Itsuki

    2006-01-01

    AKARI (formerly ASTRO-F) is an infrared space telescope designed for an all-sky survey at 10-180 (mu)m, and deep pointed surveys of selected areas at 2-180 (mu)m. The deep pointed surveys with AKARI will significantly advance our understanding of galaxy evolution, the structure formation of the Universe, the nature of the buried AGNs, and the cosmic infrared background. Here we describe the important characteristics of the AKARI mission: the orbit, and the attitude control system, and investigate the optimum survey area based on the updated pre-flight sensitivities of AKARI, taking into account the cirrus confusion noise as well as the surface density of bright stars. The North Ecliptic Pole (NEP) is concluded to be the best area for 2-26 (mu)m deep surveys, while the low-cirrus noise regions around the South Ecliptic Pole (SEP) are worth considering for 50-180 (mu)m pointed surveys to high sensitivities limited by the galaxy confusion noise. Current observational plans of these pointed surveys are described ...

  17. A HIGH PERFORMANCE OPTIMIZATION TECHNIQUE FOR POLE BALANCING PROBLEM

    Directory of Open Access Journals (Sweden)

    Bahadır KARASULU

    2008-02-01

    Full Text Available High performance computing techniques can be used effectively for solution of the complex scientific problems. Pole balancing problem is a basic benchmark tool of robotic field, which is an important field of Artificial Intelligence research areas. In this study, a solution is developed for pole balancing problem using Artificial Neural Network (ANN and high performance computation technique. Algorithm, that basis of the Reinforcement Learning method which is used to find the force of pole's balance, is transfered to parallel environment. In Implementation, C is preferred as programming language and Message Passing Interface (MPI is used for parallel computation technique. Self–Organizing Map (SOM ANN model's neurons (artificial neural nodes and their weights are distributed to six processors of a server computer which equipped with each quad core processor (total 24 processors. In this way, performance values are obtained for different number of artificial neural nodes. Success of method based on results is discussed.

  18. PLANNING THE QUALITY OF LIFE FOR TIMISOARA GROWTH POLE

    Directory of Open Access Journals (Sweden)

    Cătălina-Livia POPA

    2014-06-01

    Full Text Available This paper aims to show that planning the quality of life at local level through economic development can be a new approach for policy makers and community in improving quality of life. In this purpose, the Quality Function Deployment (QFD model will be use to planning the quality of life and to identify the main directions of economic development to support improving the quality of life at the level of Timisoara Growth Pole from Romania. The dimensions of quality of life are analyzed starting from the point of view of inhabitants. The results include a new approach in which the dimensions of quality of life are the key element that orients economic development in order to improve the quality of life of human being. The case study results refer to the main elements of quality of life at Timisoara Growth Pole and the relevant directions of economic development to improve the quality of life for Timisoara Growth Pole.

  19. Global plate tectonics and the secular motion of the pole

    Science.gov (United States)

    Soler, T.

    1977-01-01

    Astronomical data compiled during the last 70 years by the international organizations providing the coordinates of the instantaneous pole clearly shows a persistent drift of the mean pole. The differential contributions to the earth's second-order tensor of inertia were obtained and applied, resulting in no significant displacement of the earth's principal axis. In view of the above, the effect that theoretical geophysical models for absolute plate velocities may have on an apparent displacement of the mean pole as a consequence of station drifting was analyzed. The investigation also reports new values for the crustal tensor of inertia (assuming an ellipsoidal earth) and the orientation of its axis of figure, reopening the old speculation of a possible sliding of the whole crustover the upper mantle, including the supporting geophysical and astronomic evidence.

  20. Ising Spectroscopy II: Particles and poles at T>Tc

    CERN Document Server

    Zamolodchikov, Alexander

    2013-01-01

    I discuss particle content of the Ising field theory (the scaling limit of the Ising model in a magnetic field), in particular the evolution of its mass spectrum under the change of the scaling parameter. I consider both real and pure imaginary magnetic field. Here I address the high-temperature regime, where the spectrum of stable particles is relatively simple (there are from one to three particles, depending on the parameter). My goal is to understand analytic continuations of the masses to the domain of the parameter where they no longer exist as the stable particles. I use the natural tool -- the $2\\to 2$ elastic scattering amplitude, with its poles associated with the stable particles, virtual and resonance states in a standard manner. Concentrating attention on the "real" poles (those corresponding to stable and virtual states) I propose a scenario on how the pattern of the poles evolves from the integrable point $T=T_c,\\ H\

  1. Poles Living in Ireland and their Quality of Life

    Directory of Open Access Journals (Sweden)

    Agnieszka NOLKA

    2009-05-01

    Full Text Available The economic growth of Ireland resulted in a significant number of Poles migrating to Ireland following the EU enlargement in 2004. The article explores the quality of life of Poles living in Ireland. Using data from a preliminary survey conducted in 2006, several dimensions of living conditions are analysed, including interpersonal relations, material security, health and healthcare. The study shows that evaluations of almost all aspects of quality of life improved, apart from components such as healthcare and the ability to acquire help from social organisations. Also interpersonal relations, contrary to the initial assumption, were enhanced by migration to Ireland.

  2. Model for Formation of Dunes at the North Martian Pole

    Institute of Scientific and Technical Information of China (English)

    ZHU Jie; CHEN Chu-Xin

    2010-01-01

    @@ The Mars Global Surveyor Mars Orbiter Camera(MOC)took images of a series of strange horseshoe-shaped dunes at the North Martian pole in 2004.These dunes would be formed due to the strong Martian winds whose pattern is different from that on the Earth.We study the cause of the formation of these dunes and make a model for them.In this model,wind speed near the north Martian pole can be evaluated based on the shape of the dunes.We also estimate the surpassing speed of dunes of different sizes.

  3. Induction Motor with Switchable Number of Poles and Toroidal Winding

    Directory of Open Access Journals (Sweden)

    MUNTEANU, A.

    2011-05-01

    Full Text Available This paper presents a study of an induction motor provided with toroidal stator winding. The ring-type coils offer a higher versatility in obtaining a different number of pole pairs by means of delta/star and series/parallel connections respectively. As consequence, the developed torque can vary within large limits and the motor can be utilized for applications that require, for example, high load torque values for a short time. The study involves experimental tests and FEM simulation for an induction machine with three configurations of pole pairs. The conclusions attest the superiority of the toroidal winding for certain applications such as electric vehicles or lifting machines.

  4. Role of pion pole in hard exlusive meson leptoproduction

    CERN Document Server

    Goloskokov, Sergey

    2015-01-01

    We consider the pion pole contribution and transversity effects determined by the $H_T$ and $\\bar E_T$ Generalized Parton Distributions (GPDs) which are essential in hard pseudoscalar and vector meson leptoproduction. We investigate spin effects in the $\\omega$ and $\\rho^0$ reactions. It is shown that the pion pole contribution is very important in the $\\omega$ production. Such effects in the $\\rho^0$ channel are much smaller. Our results on spin asymmetries and spin density matrix elements in these reactions were found to be in good agreement with HERMES data.

  5. Second-harmonic scanning optical microscopy of poled silica waveguides

    DEFF Research Database (Denmark)

    Pedersen, Kjeld; Bozhevolnyi, Sergey I.; Arentoft, Jesper;

    2000-01-01

    Second-harmonic scanning optical microscopy (SHSOM) is performed on electric-field poled silica-based waveguides. Two operation modes of SHSOM are considered. Oblique transmission reflection and normal reflection modes are used to image the spatial distribution of nonlinear susceptibilities in the...... limitations of the two operation modes when used for SHSOM studies of poled silica-based waveguides are discussed. The influence of surface defects on the resulting second-harmonic images is also considered. ©2000 American Institute of Physics....

  6. From 'third pole' to north pole: a Himalayan origin for the arctic fox.

    Science.gov (United States)

    Wang, Xiaoming; Tseng, Zhijie Jack; Li, Qiang; Takeuchi, Gary T; Xie, Guangpu

    2014-07-22

    The 'third pole' of the world is a fitting metaphor for the Himalayan-Tibetan Plateau, in allusion to its vast frozen terrain, rivalling the Arctic and Antarctic, at high altitude but low latitude. Living Tibetan and arctic mammals share adaptations to freezing temperatures such as long and thick winter fur in arctic muskox and Tibetan yak, and for carnivorans, a more predatory niche. Here, we report, to our knowledge, the first evolutionary link between an Early Pliocene (3.60-5.08 Myr ago) fox, Vulpes qiuzhudingi new species, from the Himalaya (Zanda Basin) and Kunlun Mountain (Kunlun Pass Basin) and the modern arctic fox Vulpes lagopus in the polar region. A highly hypercarnivorous dentition of the new fox bears a striking resemblance to that of V. lagopus and substantially predates the previous oldest records of the arctic fox by 3-4 Myr. The low latitude, high-altitude Tibetan Plateau is separated from the nearest modern arctic fox geographical range by at least 2000 km. The apparent connection between an ancestral high-elevation species and its modern polar descendant is consistent with our 'Out-of-Tibet' hypothesis postulating that high-altitude Tibet was a training ground for cold-environment adaptations well before the start of the Ice Age.

  7. Advances in GRAIL Gravity Field Determination Using the Celestial Mechanics Approach

    Science.gov (United States)

    Bertone, S.; Arnold, D.; Jaeggi, A.; Beutler, G.; Mervart, L.

    2015-12-01

    The NASA mission GRAIL inherits its concept from the GRACE mission to determine the gravity field of the Moon. The use of inter-satellite Ka-band range-rate (KBRR) observations enables data acquisition even when the spacecraft are not tracked from the Earth. The data allows for a highly accurate estimation of the lunar gravity field on both sides of the Moon, which is leading to huge improvements in our understanding of its internal structure and thermal evolution. In this presentation we discuss the latest GRAIL-based lunar gravity fields generated with the Celestial Mechanics Approach using the Bernese GNSS Software. We present our recent solutions up to d/o 200, where KBRR observations and position data (GNI1B products) were used to solve for the lunar gravity field parameters in a generalized orbit determination problem. We detail our parametrization in terms of pseudo-stochastic pulses and empirical accelerations, which allows for high quality results even while using a simple model of non-gravitational forces and pre-GRAIL a priori fields. Moreover, we present our latest advances towards the computation of a lunar gravity field with improved spatial resolution.As a further extension of our processing, the GNI1B positions are replaced by the original Doppler observations of the Deep Space Network (DSN) to allow for a completely independent determination of the lunar gravity field. Based on Doppler data, we perform orbit determination by solving six initial orbital elements, dynamical parameters, and stochastic parameters in daily arcs using least squares-adjustment. The pseudo-stochastic parameters are estimated to absorb deficiencies in our dynamical modeling (e.g. due to non-gravitational forces). DSN Doppler and KBRR data are then used together with an appropriate weighting for a combined orbit determination process. We present our latest results in the orbit determination of GRAIL over the primary mission phase (PM, March-May 2012) and eventually present

  8. Quantum and Post-Newtonian Effects in the Anomalistic Period and the Mean Motion of Celestial Bodies

    CERN Document Server

    Haranas, Ioannis; Gkigkitzis, Ioannis; Kotsireas, Ilias

    2015-01-01

    We study the motion of a secondary celestial body under the influence of the corrected gravitational force of a primary. We study the effect of quantum and relativistic corrections to the gravitational potential of a primary body acting on the orbiting body. More specifically, two equations are derived to approximate the perigee/perihelion/periastron time rate of change and its total variation over one revolution (i.e., the difference between the anomalistic period and the Keplerian period) under the influence of the quantum as well as post- Newtonian accelerations. Numerical results have been obtained for the artificial Earth satellite Molnya, Mercury, and, finally, the for the HW Vir c, planetary companion.

  9. Gaia, Helios, Selene and Ouranos: the three principal celestial bodies and the sky in the ancient Greek cosmogony

    Science.gov (United States)

    Theodossiou, Efstratios; Manimanis, Vassilios N.; Dimitrijević, Milan S.; Mantarakis, Petros

    In this article we consider the role of the three principal celestial bodies, the Earth (Gaia), the Sun (Helios) and the Moon (Selene), as well as the Sky (Ouranos) in the ancient Greek cosmogony. This is done by the analysis of antique Greek texts like Orphic Hymns and the literary remains of the writers and philosophers like Aeschylus, (Pseudo) Apollodorus, Apollonius Rhodius, Aristotle, Euripides, Hesiod, Homer, Hyginus, Nonnus, Pausanias, Pindar and Sophocles, as well as by the analysis of texts of Roman writers like Cicero, Ovid and Pliny.

  10. Location selection and layout for LB10, a lunar base at the Lunar North Pole with a liquid mirror observatory

    Science.gov (United States)

    Detsis, Emmanouil; Doule, Ondrej; Ebrahimi, Aliakbar

    2013-04-01

    We present the site selection process and urban planning of a Lunar Base for a crew of 10 (LB10), with an infrared astronomical telescope, based on the concept of the Lunar LIquid Mirror Telescope. LB10 is a base designated for permanent human presence on the Moon. The base architecture is based on utilization of inflatable, rigid and regolith structures for different purposes. The location for the settlement is identified through a detailed analysis of surface conditions and terrain parameters around the Lunar North and South Poles. A number of selection criteria were defined regarding construction, astronomical observations, landing and illumination conditions. The location suggested for the settlement is in the vicinity of the North Pole, utilizing the geographical morphology of the area. The base habitat is on a highly illuminated and relatively flat plateau. The observatory in the vicinity of the base, approximately 3.5 kilometers from the Lunar North Pole, inside a crater to shield it from Sunlight. An illustration of the final form of the habitat is also depicted, inspired by the baroque architectural form.

  11. Kick, Glide, Pole! Cross-Country Skiing Fun (Part II)

    Science.gov (United States)

    Duoos, Bridget A.

    2012-01-01

    Part I of Kick, Glide, Pole! Cross-Country Skiing Fun, which was published in last issue, discussed how to select cross-country ski equipment, dress for the activity and the biomechanics of the diagonal stride. Part II focuses on teaching the diagonal stride technique and begins with a progression of indoor activities. Incorporating this fun,…

  12. POLE mutations in families predisposed to cutaneous melanoma

    DEFF Research Database (Denmark)

    Aoude, Lauren G; Heitzer, Ellen; Johansson, Peter;

    2015-01-01

    whole-genome and exome data from probands of 34 melanoma families lacking pathogenic mutations in known high penetrance melanoma susceptibility genes: CDKN2A, CDK4, BAP1, TERT, POT1, ACD and TERF2IP. We found a novel germline mutation, POLE p.(Trp347Cys), in a 7-case cutaneous melanoma family...

  13. Pole-Based Approximation of the Fermi-Dirac Function

    Institute of Scientific and Technical Information of China (English)

    Lin LIN; Jianfeng LU; Lexing YING; Weinan E

    2009-01-01

    Two approaches for the efficient rational approximation of the Fermi-Dirac function are discussed: one uses the contour integral representation and conformal map-ping, and the other is based on a version of the multipole representation of the Fermi-Dirac function that uses only simple poles. Both representations have logarithmic computational complexity. They are of great interest for electronic structure calculations.

  14. Particles as S-matrix poles: hadron democracy

    International Nuclear Information System (INIS)

    The connection between two theoretical ideas of the 1950s is traced in this article, namely that hadrons are nonfundamental, ''composite'' particles and that all physically observable particles correspond to singularities of an analytic scattering matrix. The S matrix theory developed by Werner Heisenberg in the early forties now incorporated the concepts of unitarity, invariance, analyticity and causality. The meson-exchange force meant that poles must be present in nucleon-nuclear and pion-nucleon scattering as predicted by dispersion relations. Experimental work in accessible regions determined pole residues. Pole residue became associated with force strength and pole position with particle mass. In 1959, the author discovered the so-called ''bootstrap'' theory the rho meson as a force generates a rho particle. By the end of the 1950s it was clear that all hadrons had equal status, each being bound states of other hadrons, sustained by hadron exchange forces and that hadrons are self-generated by an S-matrix bootstrap mechanism that determines all their properties. (UK)

  15. Charge quantisation without magnetic poles: A topological approach to electromagnetism

    Science.gov (United States)

    Solha, Romero

    2016-01-01

    The present work provides a theoretical explanation for the quantisation of electric charges, an open problem since Millikan's oil drop experiment in 1909. This explanation is based solely on Maxwell's theory, it recasts Electromagnetic theory under the language of complex line bundles; therefore, neither magnetic poles nor quantum mechanics are invoked.

  16. The triple-pole pomeron: Regge theory and DGLAP evolution

    OpenAIRE

    Soyez, G.

    2003-01-01

    We will explain how it is possible to link Regge theory with DGLAP evolution using a triple-pole pomeron model. We will first show that Regge theory can be used to constrain the initial condition for DGLAP evolution. We will then spell out a method to extract Regge couplings at high Q^2 using DGLAP evolution.

  17. Finite Element Analysis of Boron Diffusion in Wooden Poles

    DEFF Research Database (Denmark)

    Krabbenhøft, Kristian; Hoffmeyer, P.; Bechgaard, C.;

    2003-01-01

    The problem of describing the migration of dissolved boron in wood is treated with special reference to the commonly used remedial treatment of wooden poles. The governing equations are derived and discussed together with some of the material parameters required. The equations are solved by the f...... by the finite element method and, finally, results showing the effect of different treatment strategies are presented....

  18. Finite element analysis of boron diffusion in wooden Poles

    DEFF Research Database (Denmark)

    Krabbenhøft, Kristian; Hoffmeyer, Preben; Bechgaard, Carl;

    2004-01-01

    The problem of describing the migration of dissolved boron in wood is treated with special reference to the commonly used remedial treatment of wooden poles. The governing equations are derived and discussed together with some of the material parameters required. The equations are solved by the f...... by the finite element method and, finally, results showing the effect of different treatment strategies are presented....

  19. Finite Element Analysis of Boron Diffusion in Wooden Poles

    DEFF Research Database (Denmark)

    Krabbenhøft, Kristian; Hoffmeyer, Preben; Bechgaard, Carl;

    2004-01-01

    The problem of describing the migration of dissolved boron in wood is treated with special reference to the commonly used remedial treatment of wooden poles. The governing equations are derived and discussed together with some of the material parameters required. The equations are solved by the f...... by the finite element method and, finally, results showing the effect of different treatment strategies are presented....

  20. Type II parametric downconversion in a poled fiber

    OpenAIRE

    Zhu, Eric Y.; Lee-Kim Koon, Edward A.; Qian, Lee-Kim; Helt, L. G.; Liscidini, Marco; Sipe, J. E.; Corbari, Costantino; Canagasabey, Albert; Ibsen, Morten; Kazansky, Peter G.

    2011-01-01

    We report photon-pair generation at the 1.5-?m telecom band via continuous-wave type-II parametric downconversion in a birefringent periodically-poled silica fiber. The time- and polarization-correlations of the downconverted light are examined

  1. Poling process optimization of piezo nano composite PZT/polimer

    Science.gov (United States)

    Ridlo, M. Rosyid; Lestari, Titik; Mardiyanto, Oemry, Achiar

    2013-09-01

    The objective of poling process is to make the electric dipole directions to be parallel in the inside perovskite crystal of piezo materials. In simply way, poling was carried out by giving the two sides of a piezo material by highly electrical potential. More parallel of electrical dipoles, it is more strength the piezo characteristics. The optimization involved control of temperature, time depth and the electrical voltage. The samples was prepared by solgel method with precursor tetrabutyl titanat Ti(OC4H9)4, zirconium nitrat Zr(NO3)4ṡ5H2O, Pb(CH3COO)2ṡ3H2O and solution ethylene glycol. Molar ratio Pb:Zr:Ti = 1,1:0,52:0,48 with concidering lossed Pb. Result of solgel process is nano powder PZT. The formed nano powder PZT was then mixed with polimer PVDF and pressed 10 MPa at 150 °C with the size 15 mm in diameter. After poling, piezoelectric constant d33 was measured. The highest d33 = 45 pC/N was found at poling parameters V = 5 kV/ mm, T = 120 °C dan time depth = 1 hours.

  2. Bacterial diversity in snow on North Pole ice floes

    DEFF Research Database (Denmark)

    Hauptmann, Aviaja Zenia Edna Lyberth; Stibal, Marek; Bælum, Jacob;

    2014-01-01

    The microbial abundance and diversity in snow on ice floes at three sites near the North Pole was assessed using quantitative PCR and 454 pyrosequencing. Abundance of 16S rRNA genes in the samples ranged between 43 and 248 gene copies per millilitre of melted snow. A total of 291,331 sequences we...

  3. Poled-glass devices: Influence of surfaces and interfaces

    DEFF Research Database (Denmark)

    Fage-Pedersen, Jacob; Jacobsen, Rune Shim; Kristensen, Martin

    2007-01-01

    Devices in periodically poled glass must have a large periodic variation of the built-in field. We show that the periodic variation can be severely degraded by charge dynamics taking place at the external (glass–air) interface or at internal (glass–glass) interfaces if the interfaces have imperfe...

  4. Liz Taylor : minu van Gogh pole natsidele kuulunud

    Index Scriptorium Estoniae

    2004-01-01

    Elizabeth Taylor palus kohtult otsust, et talle kuuluvat 15 miljonit dollarit maksvat Vincent van Goghi maali "Vaade Saint-Remy varjupaigale" pole natsid Margarete Mauthneri juudiperekonna käest vägivaldselt ära võtnud. E. Taylori isa ostis maali 1963. a. Londonis oksjonilt

  5. Avoidance of a Landau Pole by Flat Contributions in QED

    CERN Document Server

    Klaczynski, Lutz

    2013-01-01

    We consider massless Quantum Electrodynamics in momentum scheme and further an ap- proach based on Dyson{Schwinger equations to approximate both the ?-function and the renormalized photon self-energy [Y11]. Starting from the Callan-Symanzik equation, we derive a renormalization group (RG) recursion identity which implies a non-linear ODE for the anomalous dimension and extract a su?cient but not necessary criterion for the existence of a Landau pole. This criterion implies a nec- essary condition for QED to have no such pole. Solving the di?erential equation exactly for a toy model case, we integrate the corresponding RG equation for the running coupling and ?nd that even though the ?-function entails a Landau pole it exhibits a at contribution capable of decreasing its growth, in other cases possibly to the extent that such a pole is avoided altogether. Finally, by applying the recursion identity, we compute the photon propagator and investigate the e?ect of at contributions on both spacelike and timelike ph...

  6. CROWtm FIELD DEMONSTRATION WITH BELL LUMBER AND POLE

    Energy Technology Data Exchange (ETDEWEB)

    Lyle A. Johnson, Jr.; L. John Fahy

    2002-03-01

    In 1990, efforts were initiated to implement an in-situ remediation project for the contaminated aquifer at the Bell Lumber and Pole Company (Bell Pole) site in New Brighton, Minnesota. The remediation project involves the application of the Contained Recovery of Oily Waste (CROW{trademark}) process, which consists of hot-water injection to displace and recover nonaqueous phase liquids. While reviewing the site evaluation information, it became apparent that better site characterization would enhance the outcome of the project. Additional coring indicated that the areal extent of the contaminated soils was approximately eight times greater than initially believed. Because of the uncertainties, in 1993, a pilot test was conducted that provided containment and organic recovery information that assisted in the design of the full-scale CROW process demonstration. After reviewing the cost ramifications of implementing the full-scale CROW field demonstration, Bell Pole approached Western Research Institute (WRI) with a request for a staged, sequential site remediation. Bell Pole's request for the change in the project scope was prompted by budgetary constraints. Bell Pole felt that although a longer project might be more costly, by extending the length of the project, the yearly cost burden would be more manageable. After considering several options, WRI recommended implementing a phased approach to remediate the contaminated area. Phase 1 involves a CROW process demonstration to remediate the upgradient one-third of the contaminated area, which contains the largest amount of free organic material. The Bell Pole Phase 1 CROW demonstration began in mid-1995 and was operated until January 2001. The operation of the demonstration was satisfactory, although at less than the design conditions. During the demonstration, 25,502,902 gal of hot water was injected and 83,155 gal of organics was transferred to the storage tank. During operations more than 65% of the produced

  7. Plotter of pole figure using data from x-ray diffraction

    International Nuclear Information System (INIS)

    Any polycrystalline aggregate normally has a preferred crystallographic orientation, or texture which depends on its thermal and or mechanical history. Preferred orientation is best described by means of a pole figure. A pole figure is a stereographic projection which shows the variation in pole density with pole orientation, for a selected set of crystal planes. In this work, computer programs was developed to plot pole figures. The corrected intensities are calculated and directly transmitted to the plotter. The different intensities levels are represented by different colors in the pole figure. (author)

  8. Inferior patellar pole fragmentation in children: just a normal variant?

    International Nuclear Information System (INIS)

    Fragmentary ossification of the inferior patella is often dismissed as a normal variant in children younger than 10 years of age. The purpose of this study was to determine whether fragmentary inferior patellar pole ossification is a normal variant or is associated with symptoms or signs of pathology using MRI and clinical exam findings as reference. A retrospective review was performed on 150 patients ages 5-10 years who underwent 164 knee radiography and MRI exams (45.1% male, mean age: 7.8 years). The presence or absence of inferior patellar pole fragmentation on radiography was correlated with the presence or absence of edema-like signal on MR images. Clinical notes were reviewed for the presence of symptoms or signs referable to the inferior patellar pole. These data were compared with a 1:1 age- and sex-matched control group without inferior pole fragmentation. Statistical analysis was performed using two-tailed t-tests. Forty of 164 (24.4%) knee radiographs showed fragmentary ossification of the inferior patella. Of these 40 knees, 62.5% (25/40) had edema-like signal of the inferior patellar bone marrow compared with 7.5% (3/40) of controls (P = 0.035). Patients with fragmentary ossification at the inferior patella had a significantly higher incidence of documented focal inferior patellar pain compared with controls (20% vs. 2.5%, P = 0.015). Inferior patellar pole fragmentation in children 5 to 10 years of age may be associated with localized symptoms and bone marrow edema-like signal and should not be routinely dismissed as a normal variant of ossification. (orig.)

  9. Inferior patellar pole fragmentation in children: just a normal variant?

    Energy Technology Data Exchange (ETDEWEB)

    Kan, J.H.; Vogelius, Esben S.; Orth, Robert C.; Guillerman, R.P.; Jadhav, Siddharth P. [Texas Children' s Hospital, E.B. Singleton Pediatric Radiology, Houston, TX (United States)

    2015-06-15

    Fragmentary ossification of the inferior patella is often dismissed as a normal variant in children younger than 10 years of age. The purpose of this study was to determine whether fragmentary inferior patellar pole ossification is a normal variant or is associated with symptoms or signs of pathology using MRI and clinical exam findings as reference. A retrospective review was performed on 150 patients ages 5-10 years who underwent 164 knee radiography and MRI exams (45.1% male, mean age: 7.8 years). The presence or absence of inferior patellar pole fragmentation on radiography was correlated with the presence or absence of edema-like signal on MR images. Clinical notes were reviewed for the presence of symptoms or signs referable to the inferior patellar pole. These data were compared with a 1:1 age- and sex-matched control group without inferior pole fragmentation. Statistical analysis was performed using two-tailed t-tests. Forty of 164 (24.4%) knee radiographs showed fragmentary ossification of the inferior patella. Of these 40 knees, 62.5% (25/40) had edema-like signal of the inferior patellar bone marrow compared with 7.5% (3/40) of controls (P = 0.035). Patients with fragmentary ossification at the inferior patella had a significantly higher incidence of documented focal inferior patellar pain compared with controls (20% vs. 2.5%, P = 0.015). Inferior patellar pole fragmentation in children 5 to 10 years of age may be associated with localized symptoms and bone marrow edema-like signal and should not be routinely dismissed as a normal variant of ossification. (orig.)

  10. The Sun, the Moon and Firmament in Chukchi Mythology and on the Relations of Celestial Bodies and Sacrifices

    Directory of Open Access Journals (Sweden)

    Ülo Siimets

    2006-01-01

    Full Text Available This article gives a brief overview of the most common Chukchi myths, notions and beliefs related to celestial bodies at the end of the 19th and during the 20th century. The firmament of Chukchi world view is connected with their main source of subsistence – reindeer herding. Chukchis are one of the very few Siberian indigenous people who have preserved their religion. Similarly to many other nations, the peoples of the Far North as well as Chukchis personify the Sun, the Moon and stars. The article also points out thesimilarities between Chukchi notions and these of other peoples. Till now Chukchi reindeer herders seek the supposed help or influence of a constellation or planet when making important sacrifices (for example, offering sacrifices in a full moon. According to the Chukchi religion the most important celestial character is the Sun. It is spoken of as an individual being (vaśrgśn. In addition to the Sun, the Creator, Dawn, Zenith, Midday and the North Star also belong to the ranks of special (superior beings. The Moon in Chukchi mythology is a man and a being in one person. It is as the ketlja (evil spiritof the Sun. Chukchi myths about several stars (such as the North Star and Betelgeuse resemble to a great extent these of other peoples.

  11. An analytical model for the celestial distribution of polarized light, accounting for polarization singularities, wavelength and atmospheric turbidity

    Science.gov (United States)

    Wang, Xin; Gao, Jun; Fan, Zhiguo; Roberts, Nicholas W.

    2016-06-01

    We present a computationally inexpensive analytical model for simulating celestial polarization patterns in variable conditions. We combine both the singularity theory of Berry et al (2004 New J. Phys. 6 162) and the intensity model of Perez et al (1993 Sol. Energy 50 235-245) such that our single model describes three key sets of data: (1) the overhead distribution of the degree of polarization as well as the existence of neutral points in the sky; (2) the change in sky polarization as a function of the turbidity of the atmosphere; and (3) sky polarization patterns as a function of wavelength, calculated in this work from the ultra-violet to the near infra-red. To verify the performance of our model we generate accurate reference data using a numerical radiative transfer model and statistical comparisons between these two methods demonstrate no significant difference in almost all situations. The development of our analytical model provides a novel method for efficiently calculating the overhead skylight polarization pattern. This provides a new tool of particular relevance for our understanding of animals that use the celestial polarization pattern as a source of visual information.

  12. Introduction on background medium theory about celestial body motion orbit and foundation of fractional-dimension calculus about self-similar fractal measure calculation

    Science.gov (United States)

    Yan, Kun

    2007-04-01

    In this paper, by discussing the basic hypotheses about the continuous orbit and discrete orbit in two research directions of the background medium theory for celestial body motion, the concrete equation forms and their summary of the theoretic frame of celestial body motion are introduced. Future more, by discussing the general form of Binet's equation of celestial body motion orbit and it's solution of the advance of the perihelion of planets, the relations and differences between the continuous orbit theory and Newton's gravitation theory and Einstein's general relativity are given. And by discussing the fractional-dimension expanded equation for the celestial body motion orbits, the concrete equations and the prophesy data of discrete orbit or stable orbits of celestial bodies which included the planets in the Solar system, satellites in the Uranian system, satellites in the Earth system and satellites obtaining the Moon obtaining from discrete orbit theory are given too. Especially, as the preliminary exploration and inference to the gravitation curve of celestial bodies in broadly range, the concept for the ideal black hole with trend to infinite in mass density difficult to be formed by gravitation only is explored. By discussing the position hypothesis of fractional-dimension derivative about general function and the formula form the hypothesis of fractional-dimension derivative about power function, the concrete equation formulas of fractional-dimension derivative, differential and integral are described distinctly further, and the difference between the fractional-dimension derivative and the fractional-order derivative are given too. Subsequently, the concrete forms of measure calculation equations of self-similar fractal obtaining by based on the definition of form in fractional-dimension calculus about general fractal measure are discussed again, and the differences with Hausdorff measure method or the covering method at present are given. By applying

  13. The Interactive Climate and Vegetation Along the Pole-Equator Belts Simulated by a Global Coupled Model

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The interaction between climate and vegetation along four Pole-Equator-Pole (PEP) belts were explored using a global two-way coupled model, AVIM-GOALS, which links the ecophysiological processes at the land surface with the general circulation model (GCM). The PEP belts are important in linking the climate change with the variation of sea and land, including terrestrial ecosystems. Previous PEP belts studies have mainly focused on the paleoclimate variation and its reconstruction. This study analyzes and discusses the interaction between modern climate and vegetation represented by leaf area index (LAI) and net primary production (NPP). The results show that the simulated LAI variation, corresponding to the observed LAI variation, agrees with the peak-valley variation of precipitation in these belts. The annual mean NPP simulated by the coupled model is also consistent with PIK NPP data in its overall variation trend along the four belts, which is a good example to promote global ecological studies by coupling the climate and vegetation models. A large discrepancy between the simulated and estimated LAI emerges to the south of 15°N along PEP 3 and to the south of 18°S in PEP 1S, and the discrepancy for the simulated NPP and PIK data in the two regions is relatively smaller in contrast to the LAI difference. Precipitation is a key factor affecting vegetation variation, and the overall trend of LAI and NPP corresponds more obviously to precipitation variation than temperature change along most parts of these PEP belts.

  14. Amplitude-phase calculations of Regge poles obtained from coupled radial Dirac equations

    Energy Technology Data Exchange (ETDEWEB)

    Thylwe, K-E [KTH-Mechanics, Royal lnstitute of Technology, S-100 44 Stockholm (Sweden); McCabe, P, E-mail: ket@mech.kth.se [CCDC, 12 Union Road, CB2 1EZ, Cambridge (United Kingdom)

    2011-07-08

    A recently developed amplitude-phase method for spinor-wave solutions is applied to the calculations of Regge pole positions and residues of Dirac particles. At a given energy the Dirac spin causes two sets of Regge poles that tend to coalesce in the non-relativistic limit. For the particular case of equal Lorentz-type vector and scalar potentials there is only one pole string, located very close to the non-relativistic pole string.

  15. Statistics of Titan's South Polar Tropospheric Clouds

    OpenAIRE

    Bouchez, Antonin H.; Brown, Michael E.

    2005-01-01

    We present the first long-term study of the behavior of the sporadically observed tropospheric clouds recently discovered near Titan's south pole. We find that one or more small individual cloud systems is present in the 70°-80° south region during every night of observation. These clouds account for 0.5%-1% of Titan's 2.0 μm flux, consistent with a global cloud cover fraction of 0.2%-0.6%. Clouds observed over multiple-night observing periods remained nearly fixed in brightness and position ...

  16. Two-dimensional multi-pole solitons in nonlocal nonlinear media

    CERN Document Server

    Rotschild, C; Kartashov, Y V; Segev, M; Torner, L; Xu, Z; Cohen, Oren; Kartashov, Yaroslav V.; Rotschild, Carmel; Segev, Mordechai; Torner, Lluis; Xu, Zhiyong

    2006-01-01

    We present the experimental observation of scalar multi-pole solitons in highly nonlocal nonlinear media, including dipole-, tri-pole, quadru-pole, and necklace-type solitons, organized as arrays of out-of-phase bright spots. These complex solitons are meta-stable, but with a large parameters range where the instability is weak, enabling their experimental observation.

  17. Double Trouble: A Rare Case of Bilateral Upper Pole Ureteropelvic Junction Obstruction

    Directory of Open Access Journals (Sweden)

    Craig A. Peters

    2014-09-01

    Full Text Available A 16-year-old girl presented with bilateral back pain caused by bilateral upper pole ureteropelvic junction obstructions; an extremely rare phenomenon. Bilateral robotically assisted upper pole pyeloplasties were preformed at the same setting with an excellent clinical response. Although rare, upper pole ureteropelvic junction obstruction is a defined entity that urologists should be aware of.

  18. Posttraumatic osteonecrosis and nonunion of distal pole of scaphoid

    Directory of Open Access Journals (Sweden)

    Saurabh Kapoor

    2013-01-01

    Full Text Available Posttraumatic osteonecrosis of distal pole of scaphoid is an extremely rare with only two reported cases so far. We present a case of a 30-year-old male with a 2-year-old posttraumatic osteonecrosis and nonunion of distal pole of scaphoid left wrist. He presented with complaints of pain and restriction of movements. There was no evidence of radiocarpal arthritis. He was managed with open reduction and internal fixation with k-wires, supplemented by a pronator quadratus based muscle pedicle bone graft. The fracture union was achieved at 6 months. After 2 years, he had almost complete range of wrist motion and had returned to his preinjury level of functional activity. His MRI (magnetic resonance imaging scans showed evidence of revascularization suggesting successful incorporation of bone graft.

  19. Study of recursive model for pole-zero cancellation circuit

    International Nuclear Information System (INIS)

    The output of charge sensitive amplifier (CSA) is a negative exponential signal with long decay time which will result in undershoot after C-R differentiator. Pole-zero cancellation (PZC) circuit is often applied to eliminate undershoot in many radiation detectors. However, it is difficult to use a zero created by PZC circuit to cancel a pole in CSA output signal accurately because of the influences of electronic components inherent error and environmental factors. A novel recursive model for PZC circuit is presented based on Kirchhoff's Current Law (KCL) in this paper. The model is established by numerical differentiation algorithm between the input and the output signal. Some simulation experiments for a negative exponential signal are carried out using Visual Basic for Application (VBA) program and a real x-ray signal is also tested. Simulated results show that the recursive model can reduce the time constant of input signal and eliminate undershoot. (authors)

  20. Neuromorphic Continuous-Time State Space Pole Placement Adaptive Control

    Institute of Scientific and Technical Information of China (English)

    卢钊; 孙明伟

    2003-01-01

    A neuromorphic continuous-time state space pole assignment adaptive controller is proposed, which is particularly appropriate for controlling a large-scale time-variant state-space model due to the parallely distributed nature of neurocomputing. In our approach, Hopfield neural network is exploited to identify the parameters of a continuous-time state-space model, and a dedicated recurrent neural network is designed to compute pole placement feedback control law in real time. Thus the identification and the control computation are incorporated in the closed-loop, adaptive, real-time control system. The merit of this approach is that the neural networks converge to their solutions very quickly and simultaneously.

  1. Pole assignment for stochastic systems with unknown coefficients

    Institute of Scientific and Technical Information of China (English)

    陈翰馥[1; 曹希仁[2

    2000-01-01

    This paper solves the exact pole assignment problem for the single-input stochastic systems with unknown coefficients under the controllability assumption which is necessary and sufficient for the arbitrary pole assignment for systems with known coefficients. The system noise is required to be mutually independent with zero mean and bounded second moment. Two approaches to solving the problem are proposed: One is the iterative learning approach which can be applied when the state at a fixed time can be repeatedly observed with different feedback gains; the other is the adaptive control approach which works when the trajectories satisfy a nondegeneracy condition. Both methods are essentially based on stochastic approximation, and the feedback gains are recursively given without invoking the certainty-equivalency-principle.

  2. Claw-pole Synchronous Generator for Compressed Air Energy Storage

    Directory of Open Access Journals (Sweden)

    PAVEL Valentina

    2013-05-01

    Full Text Available This paper presents a claw-poles generator for compressed air energy storage systems. It is presented the structure of such a system used for compensating of the intermittency of a small wind energy system. For equipping of this system it is chosen the permanent magnet claw pole synchronous generator obtained by using ring NdFeB permanentmagnets instead of excitation coil. In such a way the complexity of the scheme is reduced and the generator become maintenance free. The new magnetic flux density in the air-gap is calculated by magneticreluctance method and by FEM method and the results are compared with measured values in the old and new generator.

  3. Improvement of Electrochemical Machining Accuracy by Using Dual Pole Tool

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Electrochemical machining (ECM) is one of the best al ternatives for producing complex shapes in advanced materials used in aircraft a nd aerospace industries. However, the reduction of the stray material removal co ntinues to be major challenges for industries in addressing accuracy improvement . This study presents a method of improving machining accuracy in ECM by using a dual pole tool with a metallic bush outside the insulated coating of a cathode tool. The bush is connected with anode and so the el...

  4. Regularization of scattering calculations at R-matrix poles

    International Nuclear Information System (INIS)

    Physical quantities of scattering expressed in terms of the R-matrix are not well defined at R-matrix poles. It is shown that these unphysical singularities can be removed and the regularized expressions are obtained. The method is straightforwardly applicable to various scattering theory quantities such as the reactance matrix, the Green function, the cumulative reaction probability and the density of resonance states. (author)

  5. Tööpuudus 29%, palavikku pole / Rachel Donadio

    Index Scriptorium Estoniae

    Donadio, Rachel

    2010-01-01

    Lõuna-Hispaanias asuvas Cádizis on töötus 29%, ometi pole eurotsooni kõrgeim tööpuuduse määr tekitanud linnas sügavat sotsiaalset rahutust ega massilisi proteste, sest üsna kõrge elukvaliteedi tagavad töötutele kompleksne turvavõrk, mis koosneb varimajandusest, perekonna toetusest ja valitsuse toetusest

  6. Edgar Savisaar : BRS pole piisavalt investeerinud / Raigo Neudorf

    Index Scriptorium Estoniae

    Neudorf, Raigo

    2006-01-01

    Majandus- ja kommunikatsiooniminister on rahul, et riigi ja BRS-iga saavutati kokkulepe ettevõtte aktsiate tagasiostuks, kuid leiab, et BRS pole täitnud võetud investeerimiskohustusi ning seega peab järgnevatel aastatel suunama ettevõtte kaasajastamisse miljardeid kroone. Vt. samas: Jüri Käo: investeeringute kogumaht ületas nõutu; Savisaar: Jüri Käo ajab pada; Pingelised läbirääkimised BRS-iga

  7. Wind stress forcing of the North Sea `pole tide'

    Science.gov (United States)

    O'Connor, William P.; Chao, Benjamin Fong; Zheng, Dawei; Au, Andrew Y.

    2000-08-01

    We conduct numerical simulations of the wind forcing of sea level variations in the North Sea using a barotropic ocean model with realistic geography and bathymetry to examine the forcing of the 14 month `pole tide', which is known to be anomalously large along the Denmark-Netherlands coast. The simulation input is the monthly mean surface wind stress field from the National Centers for Environmental Prediction (NCEP) reanalysis for the 40 year period 1958-1997. The ocean model output sea level response is then compared with 10 coastal tide gauge records from the Permanent Service for Mean Sea Level (PSMSL) over the same period of time. Besides the strong seasonal variations, several prominent quasi-periodicities exist near 7 years, 3 years, 14 months, 9 months and 6.5 months. Correlations and spectral analyses show remarkable agreement between the model output and the observations, particularly in the 14 month, or Chandler, period band. The latter indicates that the enhanced pole tide found in the North Sea along the Denmark-Netherlands coast is actually the coastal set-up response to wind stress forcing with a periodicity of around 14 months. We find no need to invoke a geophysical explanation involving resonance enhancement of the pole tide in the North Sea to explain the observations.

  8. Anomaly poles as common signatures of chiral and conformal anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Armillis, Roberta, E-mail: roberta.armillis@le.infn.i [Dipartimento di Fisica, Universita del Salento and INFN Sezione di Lecce, Via Arnesano, 73100 Lecce (Italy); Coriano, Claudio, E-mail: claudio.coriano@le.infn.i [Dipartimento di Fisica, Universita del Salento and INFN Sezione di Lecce, Via Arnesano, 73100 Lecce (Italy); Department of Physics, University of Crete, Heraklion, Crete (Greece); Delle Rose, Luigi, E-mail: luigi.dellerose@le.infn.i [Dipartimento di Fisica, Universita del Salento and INFN Sezione di Lecce, Via Arnesano, 73100 Lecce (Italy)

    2009-12-07

    One feature of the chiral anomaly, analyzed in a perturbative framework, is the appearance of massless poles which account for it. They are identified by a spectral analysis of the anomaly graph and are usually interpreted as being of an infrared origin. Recent investigations show that their presence is not just confined in the infrared, but that they appear in the effective action under the most general kinematical conditions, even if they decouple in the infrared. Further studies reveal that they are responsible for the non-unitary behaviour of these theories in the ultraviolet (UV) region. We extend this analysis to the case of the conformal anomaly, showing that the effective action describing the interaction of gauge fields with gravity is characterized by anomaly poles that give the entire anomaly and are decoupled in the infrared (IR), in complete analogy with the chiral case. This complements a related analysis by Giannotti and Mottola on the trace anomaly in gravity, in which an anomaly pole has been identified in the corresponding correlator using dispersion theory in the IR. Our extension is based on an exact computation of the off-shell correlation function involving an energy-momentum tensor and two vector currents (the gauge-gauge-graviton vertex) which is responsible for the appearance of the anomaly.

  9. Anomaly Poles as Common Signatures of Chiral and Conformal Anomalies

    CERN Document Server

    Armillis, Roberta; Rose, Luigi Delle

    2009-01-01

    One feature of the chiral anomaly, analyzed in a perturbative framework, is the appearance of massless poles which account for it. They are identified by a spectral analysis of the anomaly graph and are usually interpreted as being of an infrared origin. Recent investigations shown that their presence is not just confined in the infrared, but that they appear in the effective action under the most general kinematical conditions, even if they decouple in the infrared. Further studies reveal that they are responsible for the non-unitary behaviour of these theories in the ultraviolet (UV) region. We extend this analysis to the case of the conformal anomaly, showing that the effective action describing the interaction of gauge fields with gravity is characterized by anomaly poles that give the entire anomaly and are decoupled in the infrared (IR), in complete analogy with the chiral case. This complements a related analysis by Giannotti and Mottola on the trace anomaly in gravity, in which an anomaly pole has bee...

  10. Traditions connected with the pole shift model of the Pleistocene

    CERN Document Server

    Woelfli, Willy

    2010-01-01

    As is well known, during the Last Glacial Maximum, about 20'000 years ago, the ice was asymmetrically distributed around the present North Pole. It reached the region of New York, while east Siberia remained ice free. Mammoths lived in arctic regions of east Siberia, where now their food cannot grow. Therefore the globe must have been turned in such a way that the North Pole was in Greenland. The required rapid geographic pole shift at the end of the ice ages has been shown to be physically possible, on condition that an astronomical object of planetary size in an extremely eccentric orbit existed. In this postulated situation it was red hot and a disk shaped gas cloud reduced the solar radiation on Earth in a time dependent way. A frequent objection to this hypothesis is that the phenomena should be reported in old traditions. This paper quotes such traditions from passages of Platon, Herodotus, Ovid, papyrus Ipuwer, Gilgamesh, the Bible, American Indians and other civilizations. Far from being exhaustive th...

  11. Paleomagnetic study of Siluro-Devonian volcanic rocks from the central Lachlan Orogen: Implications for the apparent pole wander path of Gondwana

    Science.gov (United States)

    VéRard, Christian; Tait, Jennifer; Glen, Richard

    2005-06-01

    The apparent pole wander (APW) path for Gondwana is still not clearly established, in particular, for Silurian-Devonian times. A controversial debate places authors who argue for an "X path," running directly through Africa on a reconstruction of Gondwana against those who advocate a large loop passing by southern South America, the "Y path." Most of the paleomagnetic data used to draw this loop come from the Lachlan Orogen (Australia). A paleomagnetic study was carried out in the well-dated Ambone and Ural volcanics in the central subprovince of Lachlan Orogen, New South Wales. Anisotropy of magnetic susceptibility measurements confirms detailed mapping of the region and shows that these massive dacitic sills and/or lava flows are flat lying. Among the different localities studied, only one yields interpretable paleomagnetic results. Two components of magnetization can be identified: a midtemperature direction yielding a corresponding pole in Australian coordinates λ = 67.9°S/ϕ = 084.4°E (B = 5; n = 21; dp = 17.5°/dm = 23.1°) and a high-temperature direction with a corresponding VGP λ = 24.4°S/ϕ = 060.6°E (B = 5; n = 25; dp = 1.4°/dm = 2.5°). The first is interpreted as corresponding to an Early Carboniferous pole position and can be regarded as an overprint probably related to the Early Carboniferous Kanimblan orogenic event. The second does not correspond to any expected Silurian-Devonian or younger pole position. This magnetization is thought to be primary in origin; however, secular variation has apparently not been averaged out in the single lava flow sampled. Therefore the earliest Devonian paleopole position probably lies in a 30° cone around the obtained VGP, and this position can only match the X-type APW path for Gondwana. It is in particular very different from coeval poles obtained in the eastern subprovince of the Lachlan Orogen, and it is mostly used as key poles supporting the Silurian-Devonian loop for the APW path of Gondwana

  12. Effect of poling time and grid voltage on phase transition and piezoelectricity of poly(vinyledene fluoride) thin films using corona poling

    Science.gov (United States)

    Mahadeva, Suresha K.; Berring, John; Walus, Konrad; Stoeber, Boris

    2013-07-01

    Corona poling was used to create piezoelectric polyvinylidene flouride (PVDF) thin films and the effects of poling time and grid voltage on the electric and physical properties of the samples was studied. Using x-ray diffraction, infrared spectroscopy, and direct measurement of piezoelectricity, the phase transition behaviour and piezoelectric constant of stretched and poled PVDF film was investigated. Results indicate that the poling time and grid voltage have no substantial influence on the phase transition behaviour of PVDF. However, they were found to have a significant effect on the piezoelectric charge constant of PVDF.

  13. Physical model simulation for resistivity tomography. An experimental tank and detection limit for a pole-pole array

    International Nuclear Information System (INIS)

    Underground hydrology is one of important items for the assessment of the high-level radioactive waste disposal. Rock fractures play an important role in local hydrology in fractured rock mass. In order to develop the technique of rock fracture survey, basic study on resistivity tomography has been carried out using an experimental tank 2x2m square and 2.2m in depth. The tank was filled with a NaCl solution to represent a homogeneous geologic media. A multi-electrode representing electrodes that will be arranged in field was used in the tank for a physical model simulation with 4 different sized fracture models. The detection limit of the resistivity tomography using a pole-pole array was discussed based on the results of both the physical and numerical model simulations. (author) 60 refs

  14. Pole-Like Object Extraction from Mobile LIDAR Data

    Science.gov (United States)

    Zheng, Han; Tan, Feitong; Wang, Ruisheng

    2016-06-01

    Object detection and recognition from LiDAR (Light Detection And Ranging) data has been a research topic in the fields of photogrammetry and computer vision. Unlike point clouds collected in well-controlled indoor environments, point clouds in urban environments are more complex due to complexity of the real world. For example, trees sometimes close to signs or buildings, which will cause occlusions in the point clouds. Current object detection or reconstruction algorithms will have problems when recognizing objects with severe occlusions caused by trees etc. In this paper, a robust vegetation removal method and a DBSCAN based pole-like object detection method are proposed. Based on observation that major difference between vegetation and other rigid objects is their penetrability with respect to LiDAR, we introduce a local roughness measure to differentiate rigid objects from non-rigid ones (vegetation in this paper). First, a local sphere with a small radius is generated for each input point. Three principal components of the local sphere are then calculated, and a plane is determined. The roughness is obtained through calculating the standard deviation of distances from all inside points to the plane by a weighted summation of the normalized distances. The further the point to the plane, the smaller the weight is. Finally, a graph cuts based method is introduced to classify the input point sets into two groups. The data term is defined by the normalized roughness of the current point, and the smoothness term is defined by the normalized distance between the point and its nearest neighbour point. In terms of pole-like object detection, first, a uniformed 2D grid is generated through projecting all the points to the XY-plane. The seed points of the pole-like objects are obtained by determining the x and y coordinates by the centres of the highest density cells of the grid and the z coordinate by the mean height of the point sets of each object. Finally, a DBSCAN

  15. POLE-LIKE OBJECT EXTRACTION FROM MOBILE LIDAR DATA

    Directory of Open Access Journals (Sweden)

    H. Zheng

    2016-06-01

    Full Text Available Object detection and recognition from LiDAR (Light Detection And Ranging data has been a research topic in the fields of photogrammetry and computer vision. Unlike point clouds collected in well-controlled indoor environments, point clouds in urban environments are more complex due to complexity of the real world. For example, trees sometimes close to signs or buildings, which will cause occlusions in the point clouds. Current object detection or reconstruction algorithms will have problems when recognizing objects with severe occlusions caused by trees etc. In this paper, a robust vegetation removal method and a DBSCAN based pole-like object detection method are proposed. Based on observation that major difference between vegetation and other rigid objects is their penetrability with respect to LiDAR, we introduce a local roughness measure to differentiate rigid objects from non-rigid ones (vegetation in this paper. First, a local sphere with a small radius is generated for each input point. Three principal components of the local sphere are then calculated, and a plane is determined. The roughness is obtained through calculating the standard deviation of distances from all inside points to the plane by a weighted summation of the normalized distances. The further the point to the plane, the smaller the weight is. Finally, a graph cuts based method is introduced to classify the input point sets into two groups. The data term is defined by the normalized roughness of the current point, and the smoothness term is defined by the normalized distance between the point and its nearest neighbour point. In terms of pole-like object detection, first, a uniformed 2D grid is generated through projecting all the points to the XY-plane. The seed points of the pole-like objects are obtained by determining the x and y coordinates by the centres of the highest density cells of the grid and the z coordinate by the mean height of the point sets of each object

  16. The limit passage of space curvature in problems of celestial mechanics with the generalized Kepler and Hooke potentials

    Science.gov (United States)

    Vozmishcheva, Tatiana

    2016-09-01

    The connection between the problems of celestial mechanics: the Kepler problem, the two-center problem and the two body problem in spaces of constant curvature with the generalized Kepler and Hooke potentials is investigated. The limit passage in the two-center and two body problems in the Lobachevsky space and on a sphere is carried out as λto0 (λ is the curvature of the corresponding space) for the two potentials. The potentials and metrics in spaces under study are written in the gnomonic coordinates. It is shown that as the curvature radius tends to infinity, the generalized gravitational and elastic potentials transform to the Kepler and Hooke forms in the Euclidean space.

  17. The Discovery of the Regular Movements of Celestial Bodies and the Development of Monotheism in the Ancient Near East

    Science.gov (United States)

    Lanfranchi, G. B.

    2011-06-01

    For Ancient Mesopotamians, astronomical phenomena were signs signifying the gods' judgment on human behaviour. Mesopotamian scholars studied celestial phenomena for understanding the gods' will, and strongly developed astrology. From the 8th to the 6th century BC Assyrian and Babylonian astronomers achieved the ability to predict solar and lunar eclipses, and the planets' movements through mathematical calculations. Predictability of astral phenomena solicited the awareness that they are all regular, and that the universe is governed by an eternal, immutable order fixed at its very beginning. This finally favoured the idea that the cosmic order depended on the will of one god only, displacing polytheism in favour of monotheism; and astrology lost its religious importance as a mean to know the divine will.

  18. Zero initial partial derivatives of satellite orbits with respect to force parameters violate the physics of motion of celestial bodies

    Institute of Scientific and Technical Information of China (English)

    XU PeiLiang

    2009-01-01

    Satellite orbits have been routinely used to produce models of the Earth's gravity field. In connection with such productions, the partial derivatives of a satellite orbit with respect to the force parameters to be determined, namely, the unknown harmonic coefficients of the gravitational model, have been first computed by setting the initial values of partial derivatives to zero. In this note, we first design some simple mathematical examples to show that setting the initial values of partial derivatives to zero is generally erroneous mathematically. We then prove that it is prohibited physically. In other words, set-ting the initial values of partial derivatives to zero violates the physics of motion of celestial bodies.

  19. Zero initial partial derivatives of satellite orbits with respect to force parameters violate the physics of motion of celestial bodies

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Satellite orbits have been routinely used to produce models of the Earth’s gravity field. In connection with such productions, the partial derivatives of a satellite orbit with respect to the force parameters to be determined, namely, the unknown harmonic coefficients of the gravitational model, have been first computed by setting the initial values of partial derivatives to zero. In this note, we first design some simple mathematical examples to show that setting the initial values of partial derivatives to zero is generally erroneous mathematically. We then prove that it is prohibited physically. In other words, set-ting the initial values of partial derivatives to zero violates the physics of motion of celestial bodies.

  20. Center of Mass of Two or More Celestial Bodies as a Basis of Comets and «Black Holes» Mechanism

    OpenAIRE

    Eugeny F. Orlov

    2012-01-01

    The article considers the questions, arising during rendezvous of two celestial bodies with equal mass, one of which is the Earth and the consequences of such rendezvous to modern civilization, suggests the idea of centers of galaxies mass with anomalously large values of the gravitational fields, which allows to divide them into two types – material filled and hollow.

  1. Center of Mass of Two or More Celestial Bodies as a Basis of Comets and «Black Holes» Mechanism

    Directory of Open Access Journals (Sweden)

    Eugeny F. Orlov

    2012-04-01

    Full Text Available The article considers the questions, arising during rendezvous of two celestial bodies with equal mass, one of which is the Earth and the consequences of such rendezvous to modern civilization, suggests the idea of centers of galaxies mass with anomalously large values of the gravitational fields, which allows to divide them into two types – material filled and hollow.

  2. Is it possible to reduce the knee joint compression force during level walking with hiking poles?

    DEFF Research Database (Denmark)

    Jensen, S B; Henriksen, M; Aaboe, J;

    2010-01-01

    Walking with hiking poles has become a popular way of exercising. Walking with poles is advocated as a physical activity that significantly reduces the loading of the hip, knee and ankle joints. We have previously observed that pole walking does not lead to a reduction of the load on the knee joint...... estimated by using a biomechanical knee joint model. The results showed that the subjects were able to increase the pole force by 2.4 times the normal pole force. However, this did not lead to a reduction in the knee joint compressive force and we rejected our hypothesis. In conclusion, the use of poles...... during level walking does not seem to reduce knee joint compressive loads. However, it is possible that the use of poles in other populations (e.g. osteoarthritis patients) and in terrain would unload the knee joint. This should be investigated in the future....

  3. [Searching for Rare Celestial Objects Automatically from Stellar Spectra of the Sloan Digital Sky Survey Data Release Eight].

    Science.gov (United States)

    Si, Jian-min; Luo, A-li; Wu, Fu-zhao; Wu, Yi-hong

    2015-03-01

    There are many valuable rare and unusual objects in spectra dataset of Sloan Digital Sky Survey (SDSS) Data Release eight (DR8), such as special white dwarfs (DZ, DQ, DC), carbon stars, white dwarf main-sequence binaries (WDMS), cataclysmic variable (CV) stars and so on, so it is extremely significant to search for rare and unusual celestial objects from massive spectra dataset. A novel algorithm based on Kernel dense estimation and K-nearest neighborhoods (KNN) has been presented, and applied to search for rare and unusual celestial objects from 546 383 stellar spectra of SDSS DR8. Their densities are estimated using Gaussian kernel density estimation, the top 5 000 spectra in descend order by their densities are selected as rare objects, and the top 300 000 spectra in ascend order by their densities are selected as normal objects. Then, KNN were used to classify the rest objects, and simultaneously K nearest neighbors of the 5 000 rare spectra are also selected as rare objects. As a result, there are totally 21 193 spectra selected as initial rare spectra, which include error spectra caused by deletion, redden, bad calibration, spectra consisting of different physically irrelevant components, planetary nebulas, QSOs, special white dwarfs (DZ, DQ, DC), carbon stars, white dwarf main-sequence binaries (WDMS), cataclysmic variable (CV) stars and so on. By cross identification with SIMBAD, NED, ADS and major literature, it is found that three DZ white dwarfs, one WDMS, two CVs with company of G-type star, three CVs candidates, six DC white dwarfs, one DC white dwarf candidate and one BL Lacertae (BL lac) candidate are our new findings. We also have found one special DA white dwarf with emission lines of Ca II triple and Mg I, and one unknown object whose spectrum looks like a late M star with emission lines and its image looks like a galaxy or nebula. PMID:26117907

  4. Measurement of South Pole ice transparency with the IceCube LED calibration system

    CERN Document Server

    Aartsen, M G; Abdou, Y; Ackermann, M; Adams, J; Aguilar, J A; Ahlers, M; Altmann, D; Auffenberg, J; Bai, X; Baker, M; Barwick, S W; Baum, V; Bay, R; Beatty, J J; Bechet, S; Tjus, J Becker; Becker, K -H; Bell, M; Benabderrahmane, M L; BenZvi, S; Berdermann, J; Berghaus, P; Berley, D; Bernardini, E; Bernhard, A; Bertrand, D; Besson, D Z; Binder, G; Bindig, D; Bissok, M; Blaufuss, E; Blumenthal, J; Boersma, D J; Bohaichuk, S; Bohm, C; Bose, D; Böser, S; Botner, O; Brayeur, L; Brown, A M; Bruijn, R; Brunner, J; Buitink, S; Carson, M; Casey, J; Casier, M; Chirkin, D; Christy, B; Clark, K; Clevermann, F; Cohen, S; Cowen, D F; Silva, A H Cruz; Danninger, M; Daughhetee, J; Davis, J C; De Clercq, C; De Ridder, S; Desiati, P; de With, M; DeYoung, T; Díaz-Vélez, J C; Dunkman, M; Eagan, R; Eberhardt, B; Eisch, J; Ellsworth, R W; Euler, S; Evenson, P A; Fadiran, O; Fazely, A R; Fedynitch, A; Feintzeig, J; Feusels, T; Filimonov, K; Finley, C; Fischer-Wasels, T; Flis, S; Franckowiak, A; Franke, R; Frantzen, K; Fuchs, T; Gaisser, T K; Gallagher, J; Gerhardt, L; Gladstone, L; Glüsenkamp, T; Goldschmidt, A; Golup, G; Goodman, J A; Góra, D; Grant, D; Groß, A; Gurtner, M; Ha, C; Ismail, A Haj; Hallgren, A; Halzen, F; Hanson, K; Heereman, D; Heimann, P; Heinen, D; Helbing, K; Hellauer, R; Hickford, S; Hill, G C; Hoffman, K D; Hoffmann, R; Homeier, A; Hoshina, K; Huelsnitz, W; Hulth, P O; Hultqvist, K; Hussain, S; Ishihara, A; Jacobi, E; Jacobsen, J; Japaridze, G S; Jero, K; Jlelati, O; Kaminsky, B; Kappes, A; Karg, T; Karle, A; Kelley, J L; Kiryluk, J; Kislat, F; Kläs, J; Klein, S R; Köhne, J -H; Kohnen, G; Kolanoski, H; Köpke, L; Kopper, C; Kopper, S; Koskinen, D J; Kowalski, M; Krasberg, M; Kroll, G; Kunnen, J; Kurahashi, N; Kuwabara, T; Labare, M; Landsman, H; Larson, M J; Lesiak-Bzdak, M; Leute, J; Lünemann, J; Madsen, J; Maruyama, R; Mase, K; Matis, H S; McNally, F; Meagher, K; Merck, M; Mészáros, P; Meures, T; Miarecki, S; Middell, E; Milke, N; Miller, J; Mohrmann, L; Montaruli, T; Morse, R; Nahnhauer, R; Naumann, U; Niederhausen, H; Nowicki, S C; Nygren, D R; Obertacke, A; Odrowski, S; Olivas, A; Olivo, M; O'Murchadha, A; Paul, L; Pepper, J A; Heros, C Pérez de los; Pfendner, C; Pieloth, D; Pirk, N; Posselt, J; Price, P B; Przybylski, G T; Rädel, L; Rawlins, K; Redl, P; Resconi, E; Rhode, W; Ribordy, M; Richman, M; Riedel, B; Rodrigues, J P; Rott, C; Ruhe, T; Ruzybayev, B; Ryckbosch, D; Saba, S M; Salameh, T; Sander, H -G; Santander, M; Sarkar, S; Schatto, K; Scheel, M; Scheriau, F; Schmidt, T; Schmitz, M; Schoenen, S; Schöneberg, S; Schönherr, L; Schönwald, A; Schukraft, A; Schulte, L; Schulz, O; Seckel, D; Seo, S H; Sestayo, Y; Seunarine, S; Sheremata, C; Smith, M W E; Soiron, M; Soldin, D; Spiczak, G M; Spiering, C; Stamatikos, M; Stanev, T; Stasik, A; Stezelberger, T; Stokstad, R G; Stößl, A; Strahler, E A; Ström, R; Sullivan, G W; Taavola, H; Taboada, I; Tamburro, A; Ter-Antonyan, S; Tilav, S; Toale, P A; Toscano, S; Usner, M; van der Drift, D; van Eijndhoven, N; Van Overloop, A; van Santen, J; Vehring, M; Voge, M; Vraeghe, M; Walck, C; Waldenmaier, T; Wallraff, M; Wasserman, R; Weaver, Ch; Wellons, M; Wendt, C; Westerhoff, S; Whitehorn, N; Wiebe, K; Wiebusch, C H; Williams, D R; Wissing, H; Wolf, M; Wood, T R; Xu, C; Xu, D L; Xu, X W; Yanez, J P; Yodh, G; Yoshida, S; Zarzhitsky, P; Ziemann, J; Zierke, S; Zilles, A; Zoll, M

    2013-01-01

    The IceCube Neutrino Observatory, approximately 1 km^3 in size, is now complete with 86 strings deployed in the Antarctic ice. IceCube detects the Cherenkov radiation emitted by charged particles passing through or created in the ice. To realize the full potential of the detector, the properties of light propagation in the ice in and around the detector must be well understood. This report presents a new method of fitting the model of light propagation in the ice to a data set of in-situ light source events collected with IceCube. The resulting set of derived parameters, namely the measured values of scattering and absorption coefficients vs. depth, is presented and a comparison of IceCube data with simulations based on the new model is shown.

  5. Mesoscale optical turbulence simulations above Dome C, Dome A and South Pole

    CERN Document Server

    Lascaux, Franck; Hagelin, Susanna; 10.1111/j.1365-2966.2010.17709.x

    2010-01-01

    In two recent papers the mesoscale model Meso-NH, joint with the Astro-Meso-NH package, has been validated at Dome C, Antarctica, for the characterization of the optical turbulence. It has been shown that the meteorological parameters (temperature and wind speed, from which the optical turbulence depends on) as well as the Cn2 profiles above Dome C were correctly statistically reproduced. The three most important derived parameters that characterize the optical turbulence above the internal antarctic plateau: the surface layer thickness, the seeing in the free-atmosphere and in the total atmosphere showed to be in a very good agreement with observations. Validation of Cn2 has been performed using all the measurements of the optical turbulence vertical distribution obtained in winter so far. In this paper, in order to investigate the ability of the model to discriminate between different turbulence conditions for site testing, we extend the study to two other potential astronomical sites in Antarctica: Dome A ...

  6. Detecting Cosmic Neutrinos with IceCube at the Earth's South Pole

    Science.gov (United States)

    Kurahashi Neilson, Naoko

    2016-01-01

    The universe has been studied using light since the dawn of astronomy, when starlight captured the human eye. The IceCube Neutrino Observatory views the universe in a different and unique way: in high-energy neutrinos. IceCube's recent discovery of a diffuse flux of astrophysical neutrinos, in other words, the universe glowing in neutrinos from beyond the solar system, started a new era of neutrino astronomy. I will motivate why neutrinos are a necessary messenger in high-energy astronomy. I will discuss the multiple diffuse flux analyses in IceCube that observe the astrophysical flux, and what each can tell us. Spatial analyses that aim to identify the sources of such astrophysical neutrinos will also be discussed, followed by an attempt to reconcile all results, to draw a coherent picture that is the state of neutrino astronomy.

  7. 1-D Air-snowpack modeling of atmospheric nitrous acid at South Pole during ANTCI 2003

    Directory of Open Access Journals (Sweden)

    W. Liao

    2008-12-01

    Full Text Available A 1-D air-snowpack model of HONO has been developed and constrained by observed chemistry and meteorology data. The 1-D model includes molecular diffusion and mechanical dispersion, windpumping in snow, gas phase to quasi-liquid layer phase HONO transfer and quasi-liquid layer nitrate and interstitial air HONO photolysis. Photolysis of nitrate is important as a dominant HONO source inside the snowpack, however, the observed HONO emission from the snowpack was triggered mainly by the equilibrium between quasi liquid layer nitrite and firn air HONO deep down the snow surface (i.e. 30 cm below snow surface. The high concentration of HONO in the firn air is subsequently transported above the snowpack by diffusion and windpumping. The model uncertainties come mainly from lack of measurements and the interpretation of the QLL properties based on the bulk snow measurements. One critical factor is the ionic strength of QLL nitrite, which is estimated here by the bulk snow pH, nitrite concentration, and QLL to bulk snow volume ratio.

  8. Galaxy Populations in the 26 most massive Galaxy Clusters in the South Pole Telescope SZE Survey

    CERN Document Server

    Zenteno, A; Desai, S; Stalder, B; Saro, A; Dietrich, J P; Bayliss, M; Bocquet, S; Chiu, I; Gonzalez, A H; Gangkofner, C; Gupta, N; Hlavacek-Larrondo, J; McDonald, M; Reichardt, C; Rest, A

    2016-01-01

    We present a study of the optical properties of the 26 most massive galaxy clusters selected within the SPT-SZ 2500 deg$^2$ survey. This Sunyaev-Zel'dovich effect selected sample spans a redshift range of 0.10 < z < 1.13. We measure the galaxy radial profile, the luminosity function (LF), and the halo occupation number (HON) using optical data with a typical depth of $m^*$ + 2. The stacked radial profiles are consistent with a NFW profile with a concentration of $2.84^{+0.40}_{-0.37}$ for the red sequence (RS) and $2.36^{+0.38}_{-0.35}$ for the total population. Stacking the data in multiple redshift bins shows a hint of redshift evolution in the concentration when both the total population is used, and when only RS galaxies are used (at 2.1$\\sigma$ and 2.8$\\sigma$, respectively). The stacked LF shows a faint end slope $\\alpha = -1.06^{+0.04}_{-0.03}$ for the total and $\\alpha = -0.80^{+0.04}_{-0.03}$ for the RS population. The redshift evolution of $m^*$ is found to be consistent with a passively evolv...

  9. From DeepCore to PINGU. Measuring atmospheric neutrino oscillations at the South Pole

    Science.gov (United States)

    Yáñez, J. P.

    2016-04-01

    Very large volume neutrino telescopes (VLVNTs) observe atmospheric neutrinos over a wide energy range (GeV to TeV), after they travel distances as large as the Earth's diameter. DeepCore, the low energy extension of IceCube, has started making meaningful measurements of the neutrino oscillation parameters θ23 and | Δm232| by analyzing the atmospheric flux at energies above 10 GeV. PINGU, a proposed project to lower DeepCore's energy threshold, aims to use the same flux to further increase the precision with which these parameters are known, and eventually determine the sign of Δm232. The latest results from DeepCore, and the planned transition to PINGU, are discussed here.

  10. From DeepCore to PINGU: Measuring atmospheric neutrino oscillations at the South Pole

    CERN Document Server

    ,

    2016-01-01

    Very large volume neutrino telescopes (VLVNTs) observe atmospheric neutrinos over a wide energy range (GeV to TeV), after they travel distances as large as the Earth's diameter. DeepCore, the low energy extension of IceCube, has started making meaningful measurements of the neutrino oscillation parameters $\\theta_{23}$ and $|\\Delta m^2_{32}|$ by analyzing the atmospheric flux at energies above 10 GeV. PINGU, a proposed project to lower DeepCore's energy threshold, aims to use the same flux to further increase the precision with which these parameters are known, and eventually determine the sign of $\\Delta m^2_{32}$. The latest results from DeepCore, and the planned transition to PINGU, are discussed here.

  11. The synergy between the dark energy survey and the South pole telescope

    International Nuclear Information System (INIS)

    The Dark Energy Survey (DES) has recently completed its science verification (SV) phase, collecting data over 150 deg2 of sky. In this work we analyze to what extent it is beneficial to supplement the analysis of DES data with cosmic microwave background (CMB) lensing data. We provide forecasts for both DES-SV and for the full survey covering 5000 deg2. We show that data presently available from DES-SV and SPT-SZ would allow a ∼8% measurement of the linear galaxy bias in three out of four redshift bins. We further show that a joint analysis of cosmic shear, galaxy density, and CMB lensing data allows to break the degeneracy between the shear multiplicative bias, the linear galaxy bias, and the normalization of the matter power spectrum. We show that these observables can thus be self-calibrated to the percent or sub-percent level, depending on the quality of available data and the fraction of overlap of the footprints and priors included in the analysis.

  12. Low frequency observations of linearly polarized structures in the interstellar medium near the south Galactic pole

    CERN Document Server

    Lenc, Emil; Sun, X H; Sadler, E M; Willis, A G; Barry, N; Beardsley, A P; Bell, M E; Bernardi, G; Bowman, J D; Briggs, F; Callingham, J R; Cappallo, R J; Carroll, P; Corey, B E; de Oliveira-Costa, A; Deshpande, A A; Dillon, J S; Dwarkanath, K S; Emrich, D; Ewall-Wice, A; Feng, L; For, B -Q; Goeke, R; Greenhill, L J; Hancock, P; Hazelton, B J; Hewitt, J N; Hindson, L; Hurley-Walker, N; Johnston-Hollitt, M; Jacobs, D C; Kapinska, A D; Kaplan, D L; Kasper, J C; Kim, H -S; Kratzenberg, E; Line, J; Loeb, A; Lonsdale, C J; Lynch, M J; McKinley, B; McWhirter, S R; Mitchell, D A; Morales, M F; Morgan, E; Morgan, J; Murphy, T; Neben, A R; Oberoi, D; Offringa, A R; Ord, S M; Paul, S; Pindor, B; Pober, J C; Prabu, T; Procopio, P; Riding, J; Rogers, A E E; Roshi, A; Shankar, N Udaya; Sethi, S K; Srivani, K S; Staveley-Smith, L; Subrahmanyan, R; Sullivan, I S; Tegmark, M; Thyagarajan, Nithyanandan; Tingay, S J; Trott, C; Waterson, M; Wayth, R B; Webster, R L; Whitney, A R; Williams, A; Williams, C L; Wu, C; Wyithe, J S B; Zheng, Q

    2016-01-01

    We present deep polarimetric observations at 154 MHz with the Murchison Widefield Array (MWA), covering 625 deg^2 centered on RA=0 h, Dec=-27 deg. The sensitivity available in our deep observations allows an in-band, frequency-dependent analysis of polarized structure for the first time at long wavelengths. Our analysis suggests that the polarized structures are dominated by intrinsic emission but may also have a foreground Faraday screen component. At these wavelengths, the compactness of the MWA baseline distribution provides excellent snapshot sensitivity to large-scale structure. The observations are sensitive to diffuse polarized emission at ~54' resolution with a sensitivity of 5.9 mJy beam^-1 and compact polarized sources at ~2.4' resolution with a sensitivity of 2.3 mJy beam^-1 for a subset (400 deg^2) of this field. The sensitivity allows the effect of ionospheric Faraday rotation to be spatially and temporally measured directly from the diffuse polarized background. Our observations reveal large-sca...

  13. Requirements for a New Detector at the South Pole Receiving an Accelerator Neutrino Beam

    CERN Document Server

    Tang, Jian

    2011-01-01

    There are recent considerations to increase the photomultiplier density in the IceCube detector array beyond that of DeepCore, which will lead to a lower detection threshold and a huge fiducial mass for the neutrino detection. This initiative is known as "Phased IceCube Next Generation Upgrade" (PINGU). We discuss the possibility to send a neutrino beam from one of the major accelerator laboratories in the Northern hemisphere to such a detector. Such an experiment would be unique in the sense that it would be the only neutrino beam where the baseline crosses the Earth's core. We study the detector requirements for a beta beam, a neutrino factory beam, and a superbeam, where we consider both the cases of small theta_13 and large theta_13, as suggested by the recent T2K hint. We illustrate that a flavor-clean beta beam best suits the requirements of such a detector, in particular, that PINGU may replace a magic baseline detector for small values of theta_13 -- even in the absence of any energy resolution capabi...

  14. PINGU: A Vision for Neutrino and Particle Physics at the South Pole

    CERN Document Server

    ,

    2016-01-01

    The Precision IceCube Next Generation Upgrade (PINGU) is a proposed low-energy in-fill extension to the IceCube Neutrino Observatory. With detection technology modeled closely on the successful IceCube example, PINGU will provide a 6Mton effective mass for neutrino detection with an energy threshold of a few GeV. With an unprecedented sample of over 60,000 atmospheric neutrinos per year in this energy range, PINGU will make highly competitive measurements of neutrino oscillation parameters in an energy range over an order of magnitude higher than long-baseline neutrino beam experiments. PINGU will measure the mixing parameters $\\theta_{\\rm 23}$ and $\\Delta m^2_{\\rm 32}$, including the octant of $\\theta_{\\rm 23}$ for a wide range of values, and determine the neutrino mass ordering at $3\\sigma$ median significance within 4 years of operation. PINGU's high precision measurement of the rate of ${\

  15. Laparoscopic upper pole heminephroureterectomy in children: Seven-year experience

    Directory of Open Access Journals (Sweden)

    Antonio Marte

    2015-01-01

    Full Text Available Background: Minimally invasive surgery is the current approach to perform heminephroureterectomy (HN in children. This can be obtained through a transperitoneal (TP or a retroperitoneal approach. Here, we report our experience using a TP approach. Materials and Methods: From 2005 to 2014, 22 TP laparoscopic upper poles HN were performed at our institution. There were nine girls and 13 boys aged between 20 months and 6 years (mean age 3.9. Eight patients were diagnosed prenatally, 17 patients presented with urinary tract infection (UTI and three with vomiting and failure to thrive. The indication for HN was reflux nephropathy and UTI in non-functioning upper pole in 19 patients and cystic dysplasia in 1 patient. The surgical technique involved the following steps: Cystoscopic recognition; positioning of 3-4 trocar (right HN; identification of the kidney (detachment of the colon; isolation and low ligation of the dilated ureter; decrossing from renal vessels; section of the parenchyma by LigaSure; haemostasis with clips and LigaSure; drain. Results: The mean operative time was 154 min (range: 81-220 min. All patients were discharged from the 2 nd to 4 th day. Neither major complication nor conversion was recorded. 1 patient presented leakage of urine for 7 days from the drainage which resolved spontaneously. At ultrasound follow-up, 5 patients showed a secondary perirenal cyst, 2-5 cm diameter that resolved spontaneously. Conclusion: The results indicate that laparoscopic upper pole heminephrectomy is the treatment of choice in cases of non-functioning dilated lower segments of duplicated kidneys. The use of laparoscopic approach offers a good working space, a good visual control of the vessels and allows a very low isolation of the ureteral stump which counterbalance the peritoneal violation.

  16. Bacterial diversity in snow on North Pole ice floes

    DEFF Research Database (Denmark)

    Hauptmann, Aviaja Zenia Edna Lyberth; Stibal, Marek; Bælum, Jacob;

    2014-01-01

    The microbial abundance and diversity in snow on ice floes at three sites near the North Pole was assessed using quantitative PCR and 454 pyrosequencing. Abundance of 16S rRNA genes in the samples ranged between 43 and 248 gene copies per millilitre of melted snow. A total of 291,331 sequences were...... sites clustered together when compared to the underlying environments of sea ice and ocean water. The Shannon indices ranged from 2.226 to 3.758, and the Chao1 indices showed species richness between 293 and 353 for the three samples. The relatively low abundances and diversity found in the samples...

  17. AN ALGEBRAIC METHOD FOR POLE PLACEMENT IN MULTIVARIABLE SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    M. de la Sen

    2001-01-01

    This paper considers the pole placement in multivariable systems involving known delays by using dynamic controllers subject to multirate sampling. The controller parametrizations are calculated from algebraic equations which are solved by using the Kronecker product of matrices. It is pointed out that the sampling periods can be selected in a convenient way for the solvability of such equations under rather weak conditions provided that the continuous plant is spectrally controllable. Some overview about the use of nonuniform sampling is also given in order to improve the system's performance.

  18. Ülikoolid pole mängukannid / Sirje Tohver

    Index Scriptorium Estoniae

    Tohver, Sirje

    2001-01-01

    TPÜ korraldas 16. märtsil̀ 2001 ümarlaua "Ülikoolid pole mängukannid", kus oli arutusel riikliku koolitustellimuse vähenemine avalik-õiguslikele ülikoolidele. Osalesid TPÜ filoloogiateaduskonna dekaan dots. H. Mattisen, kultuuriteaduskonna dekaan prof. A. Avarand, akadeemiline prorektor dots. L. Jõgi, teadus- ja arendusprorektor prof. P. Normak, haridusminister T. Lukas, TPÜ rektor prof. M. Arvisto ja EKA rektor prof. A. Keskküla, TTÜ rektor prof. A. Keevallik, EMA õppeprorektor A. Pung

  19. South Korea

    International Nuclear Information System (INIS)

    South Korea aspires to become a major nuclear supplier in the world nuclear market. There is no doubt that South Korea has great potential to fulfill these aspirations. South Korea is well positioned in terms of competitiveness, market relationships, institutional capability, ability to deliver, and commitment to nonproliferation values. As a mercantilist state, South Korea hopes to capitalize on its close relationships with transnational nuclear corporations in this endeavor. It hopes to participate in two- or three-way joint ventures---especially with the American firms that have traditionally predominated in the South Korean domestic nuclear business---to market their nuclear wares abroad. This paper is divided into four parts. The first section describes South Korea's intent to become a nuclear supplier in the 1990s. It delineates the networks of prior transactions and relationships that South Korea may use to penetrate export markets. The second section reviews South Korea's nuclear export potential, particularly its technological acquisitions from the domestic nuclear program. These capabilities will determine the rate at which South Korea can enter specific nuclear markets. The third section describes the institutional framework in South Korea for the review and approval of nuclear exports

  20. DETECTION AND CLASSIFICATION OF POLE-LIKE OBJECTS FROM MOBILE MAPPING DATA

    Directory of Open Access Journals (Sweden)

    K. Fukano

    2015-08-01

    Full Text Available Laser scanners on a vehicle-based mobile mapping system can capture 3D point-clouds of roads and roadside objects. Since roadside objects have to be maintained periodically, their 3D models are useful for planning maintenance tasks. In our previous work, we proposed a method for detecting cylindrical poles and planar plates in a point-cloud. However, it is often required to further classify pole-like objects into utility poles, streetlights, traffic signals and signs, which are managed by different organizations. In addition, our previous method may fail to extract low pole-like objects, which are often observed in urban residential areas. In this paper, we propose new methods for extracting and classifying pole-like objects. In our method, we robustly extract a wide variety of poles by converting point-clouds into wireframe models and calculating cross-sections between wireframe models and horizontal cutting planes. For classifying pole-like objects, we subdivide a pole-like object into five subsets by extracting poles and planes, and calculate feature values of each subset. Then we apply a supervised machine learning method using feature variables of subsets. In our experiments, our method could achieve excellent results for detection and classification of pole-like objects.

  1. The Effect of Polar Vortex Disturbances on Mesopause Gravity Wave Drag in Relation to Mesopause Pole-to-Pole Coupling

    Science.gov (United States)

    de Wit, R.; Hibbins, R. E.; Espy, P. J.

    2014-12-01

    Gravity waves (GWs) play an important role in the dynamics of the mesosphere/lower thermosphere (MLT) region, linking the lower to the upper atmosphere. GW filtering by the background zonal wind is furthermore believed to be the fundamental mechanism coupling the winter stratosphere to the summer polar mesopause, in which increased planetary wave (PW) activity in the former is related to enhanced temperatures in the latter through a chain of global MLT temperature anomalies. During major Sudden Stratospheric Warmings (SSWs) the interaction between PWs and the background flow leads to increased polar stratospheric temperatures and a reversal of the climatological winds from eastward to westward. As a result, large changes in GW filtering conditions occur, making SSWs an excellent tool to empirically test the inter-hemispheric coupling mechanism. In this study, mesopause GW forcing derived from meteor radar observations over Trondheim, Norway (63°N, 10°E) during the January 2013 major SSW is discussed in light of the polar vortex strength and selective filtering conditions over the same location to show the coupling between the polar winter stratosphere and MLT. Global temperature observations obtained with the Aura Microwave Limb Sounder (MLS) are subsequently used to study the temperature signature of the SSW in the MLT region over the winter pole in relation to the observed GW forcing. Furthermore, the temperature effect of the SSW throughout the middle atmosphere is tracked, away from the winter pole toward the summer pole, and compared to the temperature structure expected from the inter-hemispheric coupling mechanism.

  2. Effects of slotting and unipolar flux on magnetic pull in a two-pole induction motor with an extra four-pole stator winding

    Energy Technology Data Exchange (ETDEWEB)

    Sinervo, A.

    2013-06-01

    This thesis is about the radial magnetic forces between the rotor and stator in twopole induction machines. The magnetic forces arise from rotor eccentricity. The asymmetric air-gap makes the flux density on one side of the rotor stronger than on the opposite side. This produces magnetic pull. The magnetic flux density distribution in the air-gap can be expressed with spatial harmonics, i.e. flux densities with different pole-pair numbers. In two-pole machines, the main part of the magnetic force is produced by the interaction of two- and fourpole flux unless the four-pole flux is damped by parallel paths in the stator winding or an extra four-pole stator winding. The rest of the force comes from the interaction of two-pole and unipolar flux and from the higher harmonics of the air-gap flux of which the slot harmonics are a major part. The force caused by the higher harmonics and the unipolar flux is studied in the case where a four-pole stator winding is used to reduce the four-pole flux. The higher harmonics are found to produce, in addition to the traditional unbalanced magnetic pull, a force similar to the effect of the unipolar flux and the two can be distinguished only by measuring the unipolar flux. In measurements at various operation points, the higher harmonics are found to produce much more force than the unipolar flux and two-pole flux but the unipolar flux is still significant. The four-pole winding also is used to actively control the four-pole flux and the magnetic forces. Designing the controller requires a low order model of the system. Such a model is derived and the effect of the slot harmonics and the unipolar flux are included in the model. Different measurements techniques and methods are presented to identify and validate the control model. The operation point dependence of the system dynamics is studied via measurements. All results are obtained from a 30 kW test motor. The rotor of the test machine has a long flexible shaft on external

  3. Uncertainty maps for asteroid shape and pole solutions

    Science.gov (United States)

    Bartczak, Przemyslaw; Dudzinski, Grzegorz

    2016-10-01

    SAGE (Shaping Asteroids with Genetic Evolution) inversion method is based on genetic algorithm to obtain pole solutions, rotation periods and non-convex shapes of asteroids (Bartczak et.al, 2014). During the process computer graphics methods are used to compare model's synthetic lightcurves to photometric observations. The method is suitable for modelling both single and binary objects. A modelling run starts with a sphere, with no assumptions about the shape, and subsequently it converges to a stable spin and shape solution. Center of mas and moment of inertia are calculated for each model.Modelling of an asteroid consists of multiple runs of the process, each of them following different path towards a stable solution. As a result we obtain a family of solutions. If enough data is provided, solutions are consistent with each other and can be used for error estimation.We choose only the best models from a family of solutions, meaning every model that fits 5% threshold above best χ2 found. By comparing them we are able to construct a map of uncertainties for the shape, showing areas in good and poor agreement with chosen models. Such map can then be represented with a 3D visualisation. Moreover, we create a map of errors for pole solutions and periods.

  4. Severity of seabed spatial competition decreases towards the poles.

    Science.gov (United States)

    Barnes, D K A; Neutel, A M

    2016-04-25

    For more than a century ecologists have considered that competitive interactions between species are more intense at low latitudes [1,2]. This is frequently invoked as either an explanation or a consequence of higher species richness in the tropics, also suggesting that competition shifts from intra- to inter-specific towards the tropics [1]. Another common assumption is that within a community, intraspecific competition needs to be relatively strong, compared to inter-specific competition, in order to enable stable coexistence of species [3]. However, many analyses have found no consistent large scale geographic patterns in the intensity of intra- or interspecific competition [4]. Here, we show a clear latitudinal trend in contest competition for space in nearshore marine environments, for bryozoans (sessile, colonial, suspension feeding animals). Bryozoans form species-rich assemblages with other encrusting fauna and flora (corraline algae), and are highly abundant across the globe [5]. We find that whilst the intensity of competition (percentage of bryozoan colonies involved in direct physical spatial interactions with bryozoan or other encrusters) differed little with latitude, its severity (percentage of bryozoan colonies involved in contests with a win/loss outcome, leading to death of the loser) was three times lower at the poles than in the tropics. The cause of this change in severity was a strong shift in taxonomic relatedness of competitors, from interactions between species of different families dominating at lower latitudes, to mainly intraspecific competition at the poles.

  5. Semantic representations in the temporal pole predict false memories.

    Science.gov (United States)

    Chadwick, Martin J; Anjum, Raeesa S; Kumaran, Dharshan; Schacter, Daniel L; Spiers, Hugo J; Hassabis, Demis

    2016-09-01

    Recent advances in neuroscience have given us unprecedented insight into the neural mechanisms of false memory, showing that artificial memories can be inserted into the memory cells of the hippocampus in a way that is indistinguishable from true memories. However, this alone is not enough to explain how false memories can arise naturally in the course of our daily lives. Cognitive psychology has demonstrated that many instances of false memory, both in the laboratory and the real world, can be attributed to semantic interference. Whereas previous studies have found that a diverse set of regions show some involvement in semantic false memory, none have revealed the nature of the semantic representations underpinning the phenomenon. Here we use fMRI with representational similarity analysis to search for a neural code consistent with semantic false memory. We find clear evidence that false memories emerge from a similarity-based neural code in the temporal pole, a region that has been called the "semantic hub" of the brain. We further show that each individual has a partially unique semantic code within the temporal pole, and this unique code can predict idiosyncratic patterns of memory errors. Finally, we show that the same neural code can also predict variation in true-memory performance, consistent with an adaptive perspective on false memory. Taken together, our findings reveal the underlying structure of neural representations of semantic knowledge, and how this semantic structure can both enhance and distort our memories.

  6. Transient Broad Specular Reflections from Titan's North Pole

    Science.gov (United States)

    Dhingra, Rajani D.; Barnes, Jason W.

    2016-10-01

    In 2014, Cassini observed rough patches or transient broad specular reflections on one of Titan's seas, Punga Mare. These observations were made by the Visual and Infrared Mapping Spectrometer (VIMS). The rough patches were interpreted to be waves on the surface of the hydrocarbon sea with slopes of 60 ± 10. Although long anticipated, this was an important observation since there was no detection of waves in the initial flybys of north polar lakes and seas until the northern summer approached.We have analyzed several recent VIMS flybys of Titan's north pole looking for these rough surfaces. Our observations are classified as clouds, mudflats, specular reflections, or waves based on VIMS color composites. We observe waves in at least two seas at the north pole, Ligeia Mare and Kraken Mare. In addition, we also observe specular reflections from the shoreline or land, indicating the wet sidewalk effect or mudflat in other flybys. Wet sidewalk observations indicate a recent rainfall event causing diffuse specular reflection.These new observations help us understand more about the weather conditions and sea-wind interaction generating waves on the seas.

  7. Towards a research pole in photonics in Western Romania

    Science.gov (United States)

    Duma, Virgil-Florin; Negrutiu, Meda L.; Sinescu, Cosmin; Rominu, Mihai; Miutescu, Eftimie; Burlea, Amelia; Vlascici, Miomir; Gheorghiu, Nicolae; Cira, Octavian; Hutiu, Gheorghe; Mnerie, Corina; Demian, Dorin; Marcauteanu, Corina; Topala, Florin; Rolland, Jannick P.; Voiculescu, Ioana; Podoleanu, Adrian G.

    2014-07-01

    We present our efforts in establishing a Research Pole in Photonics in the future Arad-Timisoara metropolitan area projected to unite two major cities of Western Romania. Research objectives and related training activities of various institutions and groups that are involved are presented in their evolution during the last decade. The multi-disciplinary consortium consists principally of two universities, UAVA (Aurel Vlaicu University of Arad) and UMF (Victor Babes Medicine and Pharmacy University of Timisoara), but also of the Arad County Emergency University Hospital and several innovative SMEs, such as Bioclinica S.A. (the largest array of medical analysis labs in the region) and Inteliform S.R.L. (a competitive SME focused on mechatronics and mechanical engineering). A brief survey of the individual and joint projects of these institutions is presented, together with their teaching activities at graduate and undergraduate level. The research Pole collaborates in R&D, training and education in biomedical imaging with universities in USA and Europe. Collaborative activities, mainly on Optical Coherence Tomography (OCT) projects are presented in a multidisciplinary approach that includes optomechatronics, precision mechanics and optics, dentistry, medicine, and biology.

  8. Severity of seabed spatial competition decreases towards the poles.

    Science.gov (United States)

    Barnes, D K A; Neutel, A M

    2016-04-25

    For more than a century ecologists have considered that competitive interactions between species are more intense at low latitudes [1,2]. This is frequently invoked as either an explanation or a consequence of higher species richness in the tropics, also suggesting that competition shifts from intra- to inter-specific towards the tropics [1]. Another common assumption is that within a community, intraspecific competition needs to be relatively strong, compared to inter-specific competition, in order to enable stable coexistence of species [3]. However, many analyses have found no consistent large scale geographic patterns in the intensity of intra- or interspecific competition [4]. Here, we show a clear latitudinal trend in contest competition for space in nearshore marine environments, for bryozoans (sessile, colonial, suspension feeding animals). Bryozoans form species-rich assemblages with other encrusting fauna and flora (corraline algae), and are highly abundant across the globe [5]. We find that whilst the intensity of competition (percentage of bryozoan colonies involved in direct physical spatial interactions with bryozoan or other encrusters) differed little with latitude, its severity (percentage of bryozoan colonies involved in contests with a win/loss outcome, leading to death of the loser) was three times lower at the poles than in the tropics. The cause of this change in severity was a strong shift in taxonomic relatedness of competitors, from interactions between species of different families dominating at lower latitudes, to mainly intraspecific competition at the poles. PMID:27115685

  9. Elemental Mercury Diffusion Processes and Concentration at the Lunar Poles

    Science.gov (United States)

    Moxley, Frederick; Killen, Rosemary M.; Hurley, Dana M.

    2011-01-01

    In 2009, the Lyman Alpha Mapping Project (LAMP) spectrograph onboard the Lunar Reconnaissance Orbiter (LRO) spacecraft made the first detection of element mercury (Hg) vapor in the lunar exosphere after the Lunar Crater Observing and Sensing Satellite (LCROSS) Centaur rocket impacted into the Cabeus crater in the southern polar region of the Moon. The lunar regolith core samples from the Apollo missions determined that Hg had a devolatilized pattern with a concentration gradient increasing with depth, in addition to a layered pattern suggesting multiple episodes of burial and volatile loss. Hg migration on the lunar surface resulted in cold trapping at the poles. We have modeled the rate at which indigenous Hg is lost from the regolith through diffusion out of lunar grains. We secondly modeled the migration of Hg vapor in the exosphere and estimated the rate of cold-trapping at the poles using a Monte Carlo technique. The Hg vapor may be lost from the exosphere via ionization, Jeans escape, or re-impact into the surface causing reabsorption.

  10. The coupled characteristics of the physical process between sea ice of two poles and Tibetan land surface

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In order to discuss the characteristics of sea ice change of strong signal area on Antarctic and Arctic and the correlation between the thermal state on the land surface of Tibetan Plateau and the atmosphere circulation of North Hemisphere or the climate changes in China, and to study the feedback mechanism among “three-pole” factors, the earlier stage “three-pole” strong signal characteristics by using statistic methods such as teleconnection,which affect the regional climate changes in China and East Asia. The cross-correlation feature and coupling effect between ice caps of North and South pole and water-thermal state on Tibetan Plateau surface are discussed as well. The contribution of three-pole's earlier stage factors to China's summer climate change and the influence of its dynamic structure are compared here. The formation mechanisms of global climate change and regional climate change of China are investigated from the aspect of qualitative correlation mode of global sea-land-air-ice.

  11. Comparison of estimated residual strength and groundline decay of replaced transmission poles with actual measurements

    Energy Technology Data Exchange (ETDEWEB)

    Bhuyan, G.S.; Palylyk, R.A. [Powertech Labs., Inc., Surrey, BC (Canada); Hsu, P.; Kilvert, B.; Zolotoochin, A. [British Columbia Hydro, Vancouver, BC (Canada)

    1995-12-31

    Residual strengths of ten 45-55 foot long western red cedar (WC) poles, removed from a line after 28 to 36 years of service, were measured by destructive tests. Effectiveness of the EDM Poletest instrument for predicting residual strength of these poles was assessed. Effectiveness of the Resistograph, an instrumented drill for locating and sizing heart rot near the groundline of these poles, was investigated. Prediction of residual strength of the the individual WC poles using the Poletest instrument was found to be unreliable. Bending strength of the good fibre of the WC poles after 28-36 years of service ranged from 1630 to 5920 psi. The resistograph instrumented drill was able to detect and quantify above groundline internal decays accurately. Recommendations concerning pole maintenance, testing, and replacement were made, taking into account the results obtained in these tests.. 3 refs., 9 figs.

  12. Influence of the absorptive part of the complex potential on the S-matrix poles

    International Nuclear Information System (INIS)

    A global method for all S-matrix poles analysis is used for non-relativistic scattering by a central rectangular potential V(r)=g V(r), with g of C . The pole function k=kl(g) is analysed by constructing the Riemann surface over the g-plane, on which k=kl(g) is a single valued and analytic function. A new class of poles is identified. The effect of the imaginary part of the potential on the S-matrix poles belonging to the old and new class of poles is clarified. Occurrence of the Σ-hypernuclear state poles as a function of the potential absorption is discussed. (authors)

  13. Pole-Like Street Furniture Decompostion in Mobile Laser Scanning Data

    Science.gov (United States)

    Li, F.; Oude Elberink, S.; Vosselman, G.

    2016-06-01

    Automatic semantic interpretation of street furniture has become a popular topic in recent years. Current studies detect street furniture as connected components of points above the street level. Street furniture classification based on properties of such components suffers from large intra class variability of shapes and cannot deal with mixed classes like traffic signs attached to light poles. In this paper, we focus on the decomposition of point clouds of pole-like street furniture. A novel street furniture decomposition method is proposed, which consists of three steps: (i) acquirement of prior-knowledge, (ii) pole extraction, (iii) components separation. For the pole extraction, a novel global pole extraction approach is proposed to handle 3 different cases of street furniture. In the evaluation of results, which involves the decomposition of 27 different instances of street furniture, we demonstrate that our method decomposes mixed classes street furniture into poles and different components with respect to different functionalities.

  14. Development and validation of system for measuring poling forces during Nordic walking

    Directory of Open Access Journals (Sweden)

    Jakub Krejčí

    2013-09-01

    Full Text Available BACKGROUND: Recently, the popularity of Nordic walking (NW has been rising steadily. Many scientific studies researched the promising and beneficial effects of this form of physical activity. However, only a few studies provided data about the forces acting on the poles. We did not find a commercially available system that enables the measurement of the poling forces. OBJECTIVE: The objective of this paper was to develop and validate a system for measuring the poling forces during NW. METHODS: Strain gauge force tranducers were mounted below the grips of standard NW poles. The transducer signals were amplified and converted to digital form for transmitting to a personal computer. Special software was developed for processing the measured data and the calculation method of output variables was described. Validation of the system was performed using a Kistler force plate. Poling cycles with peak force of about 150 N were imitated by pressing the pole over a force plate. RESULTS: A function sample of the measurement system was constructed. Validation yielded the mean absolute error of 1.1 N in case of poling cycles without pole impacts or 3.0 N in case of poling cycles with impacts. CONCLUSIONS: The validation result of our system is comparable to the results of similar systems used for measurements during cross-country skiing. The system enables independent measurement of the poling forces on both poles and the duration of measurement can be up to one hour. The system provides a tool that can be used to answer a number of questions that researches raise about NW. Understanding of the biomechanical and physiological aspects of poling action can constitute a scientific basis for promoting, teaching and training of NW.

  15. Iron Pole Shape Optimization of IPM Motors Using an Integrated Method

    Directory of Open Access Journals (Sweden)

    JABBARI, A.

    2010-02-01

    Full Text Available An iron pole shape optimization method to reduce cogging torque in Interior Permanent Magnet (IPM motors is developed by using the reduced basis technique coupled by finite element and design of experiments methods. Objective function is defined as the minimum cogging torque. The experimental design of Taguchi method is used to build the approximation model and to perform optimization. This method is demonstrated on the rotor pole shape optimization of a 4-poles/24-slots IPM motor.

  16. Lower Pole Calyceal Stone and Lithotripsy are Issues with Clearance Fact or Reality?

    Directory of Open Access Journals (Sweden)

    M. Hammad Ather

    2013-12-01

    Full Text Available The lower pole calyceal (LPC stone continues to be an enigma. The complex anatomy of the lower pole collecting system, along with other factors like acute pelvi calyceal angle and narrow and long infundibulum, are some of the complicating factors affecting stone clearance. There have been many studies assessing the impact of collecting system anatomy and most conclude that the complex anatomy of the lower pole collecting system does impact the overall stone-free rate.

  17. MOLA: Seasonal Snow Variations on Mars: Slow Flyover of the Martian North Pole

    Science.gov (United States)

    2001-01-01

    MOLA: Seasonal Snow Variations on Mars: Slow Flyover of the Martian North Pole: False Color. This is a visualization of the topography near the Martian north pole as measured with the MOLA instrument. This particular animation shows a slow zoom to the surface of the pole, a flyover of the polar cap and a slow zoom out. The surface color is based on the elevation of the topography.

  18. Control of forward stimulated polariton scattering in periodically-poled KTP crystals.

    Science.gov (United States)

    Jang, Hoon; Strömqvist, Gustav; Pasiskevicius, Valdas; Canalias, Carlota

    2013-11-01

    We report suppression of forward stimulated polariton scattering (SPS) in χ((2)) structured media. Periodic poling in KTiOPO(4) (KTP) leads to the destructive interference of phonon-polariton waves, which is responsible for the dependence of the SPS threshold on the poling period. This was confirmed by comparing the SPS thresholds in periodically-poled KTP (PPKTP) crystals with different poling periods. Further confirming the physical picture, we studied the changes in the Stokes power distribution as a function of the rotation angle of the PPKTP crystal. PMID:24216950

  19. Time domain oscillating poles: Stability redefined in Memristor based Wien-oscillators

    KAUST Repository

    Talukdar, Abdul Hafiz Ibne

    2012-07-28

    Traditionally, the necessary and sufficient condition for any system to be oscillating is that its poles are located on the imaginary (jω) axis. In this paper, for the first time, we have shown that systems can oscillate with time-domain oscillating poles. The idea is verified using a Memristor based Wien oscillator. Sustained oscillations are observed without having the poles of the system fixed on the imaginary axis and the oscillating behavior of the system poles is reported. The oscillating resistance and triangular shape of FFT are also demonstrated with mathematical reasoning and simulation results to support the unusual and surprising characteristics. © 2009 IEEE.

  20. Resonances and poles in isoscattering microwave networks and graphs

    CERN Document Server

    Lawniczak, Michal; Sirko, Leszek

    2014-01-01

    Can one hear the shape of a graph? This is a modification of the famous question of Mark Kac "Can one hear the shape of a drum?" which can be asked in the case of scattering systems such as quantum graphs and microwave networks. It addresses an important mathematical problem whether scattering properties of such systems are uniquely connected to their shapes? Recent experimental results based on a characteristics of graphs such as the cumulative phase of the determinant of the scattering matrices indicate a negative answer to this question (O. Hul, M. Lawniczak, S. Bauch, A. Sawicki, M. Kus, L. Sirko, Phys. Rev. Lett 109, 040402 (2012).). In this paper we consider important local characteristics of graphs such as structures of resonances and poles of the determinant of the scattering matrices. Using these characteristics we study experimentally and theoretically properties of graphs and directly confirm that the pair of graphs considered in the cited paper is isoscattering. The experimental results are compar...

  1. The Atacama Cosmology Telescope: Physical Properties of Sunyaev-Zel'dovich Effect Clusters on the Celestial Equator

    CERN Document Server

    Menanteau, Felipe; Barrientos, L Felipe; Battaglia, Nicholas; Bond, J Richard; Crichton, Devin; Das, Sudeep; Devlin, Mark J; Dünner, Rolando; Gralla, Megan; Hajian, Amir; Hasselfield, Matthew; Hilton, Matt; Hincks, Adam D; Hughes, John P; Infante, Leopoldo; Kosowsky, Arthur; Marriage, Tobias A; Marsden, Danica; Moodley, Kavilan; Niemack, Michael D; Nolta, Michael R; Page, Lyman A; Partridge, Bruce; Reese, Erik D; Schmitt, Benjamin L; Sievers, Jon; Spergel, David N; Staggs, Suzanne T; Switzer, Eric; Wollack, Edward J

    2012-01-01

    We present the optical and X-ray properties of 68 galaxy clusters selected via the Sunyaev-Zel'dovich Effect at 148 GHz by the Atacama Cosmology Telescope (ACT). Our sample, from an area of 504 square degrees centered on the celestial equator, is divided into two regions. The main region uses 270 square degrees of the ACT survey that overlaps with the co-added ugriz imaging from the Sloan Digital Sky Survey (SDSS) over Stripe 82 plus additional near-infrared pointed observations with the Apache Point Observatory 3.5-meter telescope. We confirm a total of 49 clusters to z~1.3, of which 22 (all at z>0.55) are new discoveries. For the second region the regular-depth SDSS imaging allows us to confirm 19 more clusters up to z~0.7, of which 10 systems are new. We present the optical richness, photometric redshifts, and separation between the SZ position and the brightest cluster galaxy (BCG). We find no significant offset between the cluster SZ centroid and BCG location and a weak correlation between optical richne...

  2. The Orientation and Precession of the Pole of Saturn - Revised

    Science.gov (United States)

    Jacobson, Robert A.; French, R. G.

    2011-04-01

    The effort to determine the orientation and precession of Saturn's pole is currently motivated by three needs: to orient the Saturn gravity field for ephemeris development and spacecraft navigation, to orient the Saturn ring plane for studies of ring structure and dynamics, and to determine Saturn's polar moment of inertia for studies of Saturn's interior. Boué, G. and Laskar, J. (2006 Icarus 185, 312) published an informative theoretical discussion of polar motion applicable to Saturn. However, their model cannot be easily used in practice. Jacobson (2007 BAAS 39, 317) presented a pole model in the standard IAU trigometric series representation based on the rigid body rotational equations of motion with couples exerted by the Sun, Titan, and Iapetus. He determined the orientation and precession by fitting Saturn ring occultation measurements, in particular: the radio occultation of Voyager 1, the occultation of the star δSco seen with the Voyager 2 Ultraviolet Spectrometer, the 1989 occultation of the star 28 Sgr seen from the Earth, the 1991 occultation of the star GSC 6323-01396 seen from HST, and ring plane crossing times (Nicholson and French, 1997 BAAS 29, 1097). We have since acquired measurements from the 1995 occultation of the star GSC 5249-01240 seen from HST and the re-reduced meansurements of the 1991 occultation (French et al. 2010 AJ 139, 1649). In this paper we present our current results using the occultation data together with satellite astrometry and tracking of the Voyager and Cassini spacecraft. We also discuss future plans for the incorporation of Cassini ring occultation observations.

  3. Co-activation based parcellation of the human frontal pole.

    Science.gov (United States)

    Ray, K L; Zald, D H; Bludau, S; Riedel, M C; Bzdok, D; Yanes, J; Falcone, K E; Amunts, K; Fox, P T; Eickhoff, S B; Laird, A R

    2015-12-01

    Historically, the human frontal pole (FP) has been considered as a single architectonic area. Brodmann's area 10 is located in the frontal lobe with known contributions in the execution of various higher order cognitive processes. However, recent cytoarchitectural studies of the FP in humans have shown that this portion of cortex contains two distinct cytoarchitectonic regions. Since architectonic differences are accompanied by differential connectivity and functions, the frontal pole qualifies as a candidate region for exploratory parcellation into functionally discrete sub-regions. We investigated whether this functional heterogeneity is reflected in distinct segregations within cytoarchitectonically defined FP-areas using meta-analytic co-activation based parcellation (CBP). The CBP method examined the co-activation patterns of all voxels within the FP as reported in functional neuroimaging studies archived in the BrainMap database. Voxels within the FP were subsequently clustered into sub-regions based on the similarity of their respective meta-analytically derived co-activation maps. Performing this CBP analysis on the FP via k-means clustering produced a distinct 3-cluster parcellation for each hemisphere corresponding to previously identified cytoarchitectural differences. Post-hoc functional characterization of clusters via BrainMap metadata revealed that lateral regions of the FP mapped to memory and emotion domains, while the dorso- and ventromedial clusters were associated broadly with emotion and social cognition processes. Furthermore, the dorsomedial regions contain an emphasis on theory of mind and affective related paradigms whereas ventromedial regions couple with reward tasks. Results from this study support previous segregations of the FP and provide meta-analytic contributions to the ongoing discussion of elucidating functional architecture within human FP. PMID:26254112

  4. Update on Pluto and Its 5 Moons Obeying the Quantization of Angular Momentum per Unit Mass Constraint of Quantum Celestial Mechanics

    OpenAIRE

    Potter F.

    2016-01-01

    In July, 2015, the New Horizons spacecraft passing by Pluto did not discover any more moons. Therefore, we know the Pluto system total angular momentum to within 2.4%, more accurately than any other system with more than two orbiting bodies. We there- fore update our previous analysis to determine whether a definitive test of the quantum celestial mechanics (QCM) angular momentum constraint can now be achieved.

  5. Update on Pluto and Its 5 Moons Obeying the Quantization of Angular Momentum per Unit Mass Constraint of Quantum Celestial Mechanics

    Directory of Open Access Journals (Sweden)

    Potter F.

    2016-01-01

    Full Text Available In July, 2015, the New Horizons spacecraft passing by Pluto did not discover any more moons. Therefore, we know the Pluto system total angular momentum to within 2.4%, more accurately than any other system with more than two orbiting bodies. We there- fore update our previous analysis to determine whether a definitive test of the quantum celestial mechanics (QCM angular momentum constraint can now be achieved.

  6. El recurso a la intercesión celestial en la hora de la muerte. Un estudio sobre los testamentos navarros.

    OpenAIRE

    García-de-la-Borbolla, Á. (Ángeles)

    2005-01-01

    El recurso a la intercesión celestial en la hora de la muerte fue una constante en la actitud del hombre medieval con respecto a la muerte. Las donaciones de la alta Edad Media y los testamentos de la baja Edad Media muestran el activo papel de los santos, mártires y confesores, la Virgen María, madre de Dios, y Cristo, para la salvación eterna de los fieles.

  7. Photometric behaviour of eta Carinae, a celestial Chinese lantern: 1974-1998

    Science.gov (United States)

    van Genderen, A. M.; Sterken, C.; de Groot, M.; Burki, G.

    1999-03-01

    -ray/hot spot, with a life-time of at most a few months, could also be the cause of the instantanious physical change of the luminous disk mentioned above (and its 5.52 y modulation) visible in the UV, since both happen at the same time. Apart from the 5.52 y period in the UV, we found a striking 200 d-oscillation, also in the UV, during the last orbital cycle beween 1992.5 and 1998.0. Its possible explanation depends on whether it is cyclic or truly periodic (in the latter case eta Car could hide a triple star). Based on observations obtained at the former Leiden Southern Station in South Africa and the European Southern Observatory at La Silla, Chile

  8. Effect of materials and manufacturing on the bending stiffness of vaulting poles

    Science.gov (United States)

    Davis, C. L.; Kukureka, S. N.

    2012-09-01

    The increase in the world record height achieved in pole vaulting can be related to the improved ability of the athletes, in terms of their fitness and technique, and to the change in materials used to construct the pole. For example in 1960 there was a change in vaulting pole construction from bamboo to glass fibre reinforced polymer (GFRP) composites. The lighter GFRP pole enabled the athletes to have a faster run-up, resulting in a greater take-off speed, giving them more kinetic energy to convert into potential energy and hence height. GFRP poles also have a much higher failure stress than bamboo, so the poles were engineered to bend under the load of the athlete, thereby storing elastic strain energy that can be released as the pole straightens, resulting in greater energy efficiency. The bending also allowed athletes to change their vaulting technique from a style that involved the body remaining almost upright during the vault to one where the athlete goes over the bar with their feet upwards. Modern vaulting poles can be made from GFRP and/or carbon fibre reinforced polymer (CFRP) composites. The addition of carbon fibres maintains the mechanical properties of the pole, but allows a reduction in the weight. The number and arrangement of the fibres determines the mechanical properties, in particular the bending stiffness. Vaulting poles are also designed for an individual athlete to take into account each athlete’s ability and physical characteristics. The poles are rated by ‘weight’ to allow athletes to select an appropriate pole for their ability. This paper will review the development of vaulting poles and the requirements to maximize performance. The properties (bending stiffness and pre-bend) and microstructure (fibre volume fraction and lay-up) of typical vaulting poles will be discussed. Originally published as Davis C L and Kukureka S N (2004) Effect of materials and manufacturing on the bending stiffness of vaulting poles The Engineering of

  9. Schistosomes in South African penguins.

    Science.gov (United States)

    Aldhoun, Jitka A; Horne, Elizabeth C

    2015-01-01

    During the years 2009-2012, faeces of African penguins (Spheniscus demersus L.) from South African rehabilitation centres were examined for helminths. In total, 46 out 555 samples (8.29 %), mostly belonging to adult birds, were found to contain oval schistosome eggs with a spine on one pole. Their dimensions were 153.21 ± 9.07 × 87.14 ± 8.67 μm. Selected DNA fragments (18S, 28S and ITS rDNA) were sequenced and compared to other schistosome isolates deposited in GenBank. The shape of the eggs suggests that they belong to the genus Gigantobilharzia; however, due to the insufficient stage of knowledge of the genus and limited number of species available for comparison, we were not able to assign the isolate unambiguously to this genus based on either the egg morphology or the results of molecular analysis.

  10. Water Ice Permafrost at Lunar Poles: Observational Evidence from Lend Instrument Onboard Lro

    Science.gov (United States)

    Mitrofanov, I.; Sanin, A.; Litvak, M.; Boynton, W. V.; Chin, G.; Evans, L. G.; Garvin, J.; Harshman, K.; McClanahan, T. R.; Milikh, G. M.; Sagdeev, R.; Starr, R. D.

    2012-12-01

    Lunar Exploration Neutron Detector (LEND) of LRO measured the flux of epithermal neutrons with high spatial resolution of 10 km for the amplitude of 50 km. The LEND data from the polar caps above 80degree latitude were tested for the presence of local spots of epithermal Neutron Suppression Regions (NSRs) [1, 2]. Six such spots have been found, five at South pole and one at North pole. One of them, NSR S4 in the Cabeus crater, has been suggested, as the best impact site for direct evaluation of the content of lunar volatiles, including the water, by LCROSS instruments [3]. And indeed, a lot of water has been found in the plume, corresponding to 5.6 +/- 2.4 weight % [4]. Another interesting spot NSR S1 is identified with the crater Shoemaker, which PSR perfectly coincides with the contour of the strong neutron suppression. It was shown [5] that there is very good agreement between the profile of the crater depth and the decrease of the flux of epithermal neutrons. Concluding the LEND data analysis of NSRs, one may present two main results: (1) Only two of NSRs are associated with PSRs (Cabeus and Shoemaker), another large PSRs do not manifest a signature of local neutron suppression. (2) There are several NSRs, which have surface illuminated by Sun light. These results could be interpreted by the model of water ice perma-frost, which suggest that NSRs are associated with spots with permanently cold regolith with stable water ice in the porosity volume. In PSRs, the ice bearing layer is the upper most one. If the surface of NSR is periodically illuminated, the ice bearing layer should lie below the top layer of ice-free regolith. During a night, the cold top layer absorbs water molecules from the exosphere (still illuminated nearby hills could be source of these molecules). During a day, the top layer is heated, and water molecules diffuse from the porosity volume into the both directions: upward to exosphere, and downward to the cold layer of permafrost. Such

  11. High-resolution second-harmonic microscopy of poled silica waveguides

    DEFF Research Database (Denmark)

    Beermann, Jonas; Bozhevolnyi, Sergey I.; Pedersen, Kjeld;

    2003-01-01

    A second-harmonic scanning optical microscopy (SHSOM) apparatus operating in reflection is used for high-resolution imaging of second-order optical non-linearities (SONs) in electric-field poled silica-based waveguides. SHSOM of domain walls in a periodically poled KTiOPO4 crystal is performed...

  12. Risk Management in the Original Extreme Sporting Event: The Pole Vault

    Science.gov (United States)

    Bemiller, Jim; Hardin, Robin

    2010-01-01

    The pole vault was considered the ultimate test of physical ability and daring before the advent of modern extreme sports such as skateboarding, snowboarding, and mountain biking. The inherent risks of the pole vault have been well documented. The National Center for Catastrophic Sport Injury Research reported in 2007 that the catastrophic injury…

  13. Threshold for strong thermal dephasing in periodically poled KTP in external cavity frequency doubling

    DEFF Research Database (Denmark)

    Lundeman, Jesper Holm; Jensen, Ole Bjarlin; Andersen, Peter E.;

    2009-01-01

    We present a measurement series of the efficiency of periodically poled KTP used for second-harmonic generation in an external phase-locked cavity. Due to the high absorption (0.01 cm^−1) in the PPKTP crystal at the pump wavelength a strong thermal dephasing of the periodically poled grating is o...

  14. 49 CFR 234.243 - Wire on pole line and aerial cable.

    Science.gov (United States)

    2010-10-01

    ... Maintenance, Inspection, and Testing Maintenance Standards § 234.243 Wire on pole line and aerial cable. Wire... transmission line operating at voltage of 750 volts or more shall be placed not less than 4 feet above the... 49 Transportation 4 2010-10-01 2010-10-01 false Wire on pole line and aerial cable....

  15. An improved torque density Modulated Pole Machine for low speed high torque applications

    DEFF Research Database (Denmark)

    Washington, J. G.; Atkinson, G. J.; Baker, N. J.;

    2012-01-01

    This paper presents a new topology for three-phase Modulated Pole Machines. This new topology the “Combined Phase Modulated Pole Machine” is analysed and compared to the more traditional technology of three separate single phase units stacked axially with a separation between phases. Three- dimen...

  16. THE INSPECTION METHOD OF INTERCELL CONNECTIONS AND POLE TERMINALS OF LEAD-ACID STORAGE BATTERIES

    Directory of Open Access Journals (Sweden)

    V. A. Dzenzersjkyj

    2010-06-01

    Full Text Available The inspection method of intercell connections and pole terminals of lead-acid storage batteries is upgraded. The method allows reducing losses from rejects, increasing reliability of check of intercell connections and pole terminals, improving the quality of storage batteries.

  17. Reducing hot-short cracking in iridium GTA welding using four-pole oscillation

    International Nuclear Information System (INIS)

    Hot-short cracking, an intrinsic problem in iridium welding, has been reduced using four-pole magnetic arc oscillation. For given batches of iridium, reject rates have been reduced from 26% to 2%. The mechanics of the four-pole oscillator, the microstructural effects and the causes for improvement are discussed

  18. Design of a mosquito trap support pole for use with CDC miniature light traps.

    Science.gov (United States)

    Evans, Christopher L; Wozniak, Arthur; McKenna, Bruce; Vaughan, David R; Dowda, Michael C

    2005-03-01

    A mosquito trap support pole constructed from polyvinyl chloride and aluminum pipes was designed to hang a Centers for Disease Control and Prevention miniature light trap and dry ice container. Miniature light traps normally hang from tree branches. The trap support pole is designed to hang traps and dry ice bait in areas where no suitable trees exist. PMID:15825774

  19. The practice of pole dance as a leisure activity in Denmark

    DEFF Research Database (Denmark)

    Jensen, Andorra Lynn

    2015-01-01

    The aim of this study is to explore the how pole dance is practiced as a form of leisure activity in Denmark. The methodical approach is qualitative and inspired by ethnography. I have conducted a field study where I have observed and participated in the pole dance culture in Copenhagen from May ...

  20. Germline variants in POLE are associated with early onset mismatch repair deficient colorectal cancer

    NARCIS (Netherlands)

    Elsayed, F.A.; Kets, C.M.; Ruano, D.; Akker, B. van den; Mensenkamp, A.R.; Schrumpf, M.; Nielsen, M.; Wijnen, J.T.; Tops, C.M.; Ligtenberg, M.J.; Vasen, H.F.A.; Hes, F.J.; Morreau, H.; Wezel, T. van

    2015-01-01

    Germline variants affecting the exonuclease domains of POLE and POLD1 predispose to multiple colorectal adenomas and/or colorectal cancer (CRC). The aim of this study was to estimate the prevalence of previously described heterozygous germline variants POLE c.1270C>G, p.(Leu424Val) and POLD1 c.14

  1. Laser assisted modification of poled silver-doped nanocomposite soda-lime glass

    OpenAIRE

    Drevinskas Rokas; Beresna Martynas; Deparis Olivier; Kazansky Peter G.

    2013-01-01

    Thermal poling assisted homogenization of polydisperse Ag nanoparticles embedded in the soda-lime glass is demonstrated. The homogenization leads to the narrowing of the localized surface plasmon resonance. The subsequent irradiation with linearly polarized ultrashort laser pulses induces spectrally defined and four times larger dichroism than in non-poled sample.

  2. Laser assisted modification of poled silver-doped nanocomposite soda-lime glass

    Directory of Open Access Journals (Sweden)

    Drevinskas Rokas

    2013-11-01

    Full Text Available Thermal poling assisted homogenization of polydisperse Ag nanoparticles embedded in the soda-lime glass is demonstrated. The homogenization leads to the narrowing of the localized surface plasmon resonance. The subsequent irradiation with linearly polarized ultrashort laser pulses induces spectrally defined and four times larger dichroism than in non-poled sample.

  3. Autonomous navigation method of high elliptical orbit satellite based on celestial navigation and GPS%基于天文/GPS的HEO卫星自主导航方法

    Institute of Scientific and Technical Information of China (English)

    王鹏; 张迎春

    2015-01-01

    为了实现大椭圆轨道(HEO)卫星高精度自主导航,提出一种将直接敏感地平天文导航与全球定位系统(GPS)相结合的组合导航方法.首先,分析卫星轨道��2运动模型及其所受空间摄动,建立卫星轨道动力学模型;然后,分析单一使用天文导航和GPS的优缺点,根据HEO卫星对GPS的可见性,提出在远地点只采用天文导航,而在近地点采用以天文导航为主、适时引入GPS信号进行位速测量辅助修正的方法.通过计算机仿真和结果分析表明了所提出的设计方法导航精度比单一天文导航提高72.4%∼85.6%.%In order to realize autonomous and continuous navigation information outputs for high elliptical orbit(HEO) satellite, new integrated navigation system is proposed based on celestial navigation of directly sensing stellar and global positioning system(GPS) navigation. Firstly, satellite orbit motion model is established on the satellite orbit dynamics��2 model and suffered space perturbation. Moreover, performances of single-use celestial navigation or GPS are analyzed. When the satellite is near the apogee, observation system is established by using only celestial navigation. When the satellite is near the perigee, the estimate covariance is revised through incoming GPS signal to improve the celestial navigation estimate. The autonomous navigation system is designed and simulating. The results of computer simulation show that the navigation accuracy is improved by 72.4%∼85.6%compared with the celestial navigation method.

  4. Glass fiber -reinforced plastic tapered poles for transmission and distribution lines: development and experimental study

    International Nuclear Information System (INIS)

    A research project to develop lightweight poles for use in power transmission and distribution lines and involving the use of glass fiber-reinforced plastic using the filament winding process is described. Twelve full scale specimen poles were designed, fabricated and subjected to cantilever bending to test failure modes. The test parameters included fiber orientation, ratio of longitudinal-to-circumferential fiber, and the number of layers. Results showed that local buckling was the most dominant failure mode, attributable to the high radius-to-thickness ratio of the specimen poles. Overall, however, these fiber-reinforced plastic poles compared favourably to wooden poles in carrying capacity with significant weight reduction. Lateral displacement at ultimate loads did not exceed the acceptable limit of 10 per cent of the specimen free length. 7 refs., 3 tabs., 2 figs

  5. Nonlinear optical polyimide with high thermal stability prepared by simultaneous poling and polymerization

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The high Tg polyimide embedded with a novel imidazol-typed chromophore 2-[5-(4-nitrostilbenyl)thienyl]- 4,5-di(4-aminophenyl)imidazole (NSTDAPI) was prepared using the "simultaneous poling and polymerization" technique. The glass transition temperature (Tg) is 304℃ and the initial decomposition temperature (Td) is 330℃. The in-situ second harmonic generation (in-situ SHG) measurement was performed to study its poling behavior and the stability of the poling-induced orientation. The nonlinear optical (NLO) coefficient d33 of poled polyimide film is 32.2 pm/V at 1064 nm fundamental wavelength. The SHG signal of the poled polymer film was quite stable below 200℃, and then began to decay rapidly above 220°C. The half-decay temperature of dipole orientation for the film is 250℃.

  6. North Pole ice thickness and association with ice motion history 1977-1992

    Science.gov (United States)

    Shy, Timothy L.; Walsh, John E.

    Ice drafts measured by U.S. Navy submarine sonar near the North Pole from 1977 to 1992 were used together with Arctic Ocean drifting buoy data from 1979 to 1992 to investigate North Pole ice thickness changes during this 15-year period. A primary objective was to determine dynamical forcing mechanisms and associated time scales relevant to ice thickness variation. North Pole ice thickness showed much interannual variability, and no systematic decrease of ice thickness was observed. Changes in ice thickness were closely associated with long-term directional deviation of ice motion from geostrophic wind-forcing, and with ice convergence and divergence at the North Pole during the 1-2 weeks prior to submarine measurement. The geographic origin of ice within the Arctic Ocean was not associated with its eventual thickness at the North Pole.

  7. Membrane recycling at the infranuclear pole of the outer hair cell

    Science.gov (United States)

    Harasztosi, Csaba; Harasztosi, Emese; Gummer, Anthony W.

    2015-12-01

    Rapid endocytic activity of outer hair cells (OHCs) in the guinea-pig cochlea has been already studied using the fluorescent membrane marker FM1-43. It was demonstrated that vesicles were endocytosed at the apical pole of OHCs and transcytosed to the basolateral membrane and through a central strand towards the nucleus. The significance of endocytic activity in the infranuclear region is still not clear. Therefore, in this study endocytic activity at the synaptic pole of OHCs was investigated. Confocal laser scanning microscopy was used to visualize dye uptake of OHCs isolated from the guinea-pig cochlea. Signal intensity changes were quantified in the apical and basal poles relative to the signal at the membrane. Data showed no significant difference in fluorescent signal intensity changes between the opposite poles of the OHC. These results suggest that endocytic activities in both the basal and the apical poles contribute equally to the membrane recycling of OHCs.

  8. South Africa

    International Nuclear Information System (INIS)

    This paper reports that South Africa's main reason for entering the international nuclear market is, and always has been, to sell its uranium abroad. From 1939-45 South Africa took part in the war against Nazi Germany, and the South African government of the time sought to help the Allied war effort in all ways that were practical. Later, during the Cold War, it tried to help build up the West's nuclear arsenal. In 1944, the British government secretly asked General Smuts---prime minister of South Africa since 1939 and a member of Churchill's War Cabinet---to survey South Africa's deposits of uranium. The survey, carried out with U.S. and British help, showed that the deposits were large, generally low-grade, but, in most cases, associated with gold and therefore could be profitably mined. In 1951, South Africa became a significant producer, with lucrative contracts for the sale of all its output to the U.S.-U.K.-Canada Joint Development Agency and one of the three main suppliers to the U.S. nuclear weapons program. In time, government controls eased and uranium production and marketing became a purely commercial operation

  9. Reliability assessment of power pole infrastructure incorporating deterioration and network maintenance

    International Nuclear Information System (INIS)

    There is considerable investment in timber utility poles worldwide, and there is a need to examine the structural reliability and probability based management optimisation of these power distribution infrastructure elements. The work presented in this paper builds on the existing studies in this area through assessment of both treated and untreated timber power poles, with the effects of deterioration and network maintenance incorporated in the analysis. This more realistic assessment approach, with deterioration and maintenance considered, was achieved using event-based Monte Carlo simulation. The output from the probabilistic model is used to illustrate the importance of considering network maintenance in the time-dependent structural reliability assessment of timber power poles. Under wind load, treated and untreated poles designed and maintained in accordance with existing Australian standards were found to have similar failure rates. However, untreated pole networks required approximately twice as many maintenance based pole replacements to sustain the same level of reliability. The effect of four different network maintenance strategies on infrastructure performance was also investigated herein. This assessment highlighted the fact that slight alterations to network maintenance practices can lead to significant changes in performance of timber power pole networks. - Highlights: • A time-dependent structural reliability model was developed for timber power poles. • Deterioration and network maintenance were incorporated into this event based model. • Network maintenance had a significant impact on power pole wind vulnerability. • Treated and untreated poles designed to Australian standards had similar reliability. • Minor alterations to maintenance strategies had large effects on network performance

  10. An Optical Source Catalog of the North Ecliptic Pole Region

    CERN Document Server

    Hwang, Narae; Lee, Hyung Mok; Im, Myungshin; Kim, Taehyun; Matsuhara, Hideo; Wada, Takehiko; Oyabu, Shinki; Pak, Soojong; Chun, Moo-Young; Watarai, Hidenori; Nakagawa, Takao; Pearson, Chris; Takagi, Toshinobu; Hanami, Hitoshi; White, Glenn J

    2007-01-01

    We present a five (u*,g',r',i',z') band optical photometry catalog of the sources in the North Ecliptic Pole (NEP) region based on deep observations made with MegaCam at CFHT. The source catalog covers about 2 square degree area centered at the NEP and reaches depths of about 26 mag for u*, g', r' bands, about 25 mag for i' band, and about 24 mag for z' band (4 sigma detection over an 1 arcsec aperture). The total number of cataloged sources brighter than r'= 23 mag is about 56,000 including both point sources and extended sources. From the investigation of photometric properties using the color-magnitude diagrams and color-color diagrams, we have found that the colors of extended sources are mostly (u*-r') 0.5. This can be used to separate the extended sources from the point sources reliably, even for the faint source domain where typical morphological classification schemes hardly work efficiently. We have derived an empirical color-redshift relation of the red sequence galaxies using the Sloan Digital Sky...

  11. Air Temperature Estimation over the Third Pole Using MODIS LST

    Science.gov (United States)

    Zhang, H.; Zhang, F.; Ye, M.; Che, T.

    2015-12-01

    The Third Pole is centered on the Tibetan Plateau (TP), which is the highest large plateau around the world with extremely complex terrain and climate conditions, resulting in very scarce meteorological stations especially in the vast west region. For these unobserved areas, the remotely sensed land surface temperature (LST) can greatly contribute to air temperature estimation. In our research we utilized the MODIS LST production from both TERRA and AQUA to estimate daily mean air temperature over the TP using multiple statistical models. Other variables used in the models include longitudes, latitudes, Julian day, solar zenith, NDVI and elevation. To select a relatively optimal model, we chose six popular and representative statistical models as candidate models including the multiple linear regression (MLR), the partial least squares regression (PLS), back propagate neural network (BPNN), support vector regression (SVR), random forests (RF) and Cubist regression (CR). The performances of the six models were compared for each possible combination of LSTs at four satellite pass times and two quality situations. Eventually a ranking table consisting of optimal models for each LST combination and quality situation was built up based on the validation results. By this means, the final production is generated providing daily mean air temperature with the least cloud blockage and acceptable accuracy. The average RMSEs of cross validation are mostly around 2℃. Stratified validations were also performed to test the expansibility to unobserved and high-altitude areas of the final models selected.

  12. Using airborne HIAPER Pole-to-Pole Observations (HIPPO) to evaluate model and remote sensing estimates of atmospheric carbon dioxide

    Science.gov (United States)

    Frankenberg, Christian; Kulawik, Susan S.; Wofsy, Steven C.; Chevallier, Frédéric; Daube, Bruce; Kort, Eric A.; O'Dell, Christopher; Olsen, Edward T.; Osterman, Gregory

    2016-06-01

    In recent years, space-borne observations of atmospheric carbon dioxide (CO2) have been increasingly used in global carbon-cycle studies. In order to obtain added value from space-borne measurements, they have to suffice stringent accuracy and precision requirements, with the latter being less crucial as it can be reduced by just enhanced sample size. Validation of CO2 column-averaged dry air mole fractions (XCO2) heavily relies on measurements of the Total Carbon Column Observing Network (TCCON). Owing to the sparseness of the network and the requirements imposed on space-based measurements, independent additional validation is highly valuable. Here, we use observations from the High-Performance Instrumented Airborne Platform for Environmental Research (HIAPER) Pole-to-Pole Observations (HIPPO) flights from 01/2009 through 09/2011 to validate CO2 measurements from satellites (Greenhouse Gases Observing Satellite - GOSAT, Thermal Emission Sounder - TES, Atmospheric Infrared Sounder - AIRS) and atmospheric inversion models (CarbonTracker CT2013B, Monitoring Atmospheric Composition and Climate (MACC) v13r1). We find that the atmospheric models capture the XCO2 variability observed in HIPPO flights very well, with correlation coefficients (r2) of 0.93 and 0.95 for CT2013B and MACC, respectively. Some larger discrepancies can be observed in profile comparisons at higher latitudes, in particular at 300 hPa during the peaks of either carbon uptake or release. These deviations can be up to 4 ppm and hint at misrepresentation of vertical transport. Comparisons with the GOSAT satellite are of comparable quality, with an r2 of 0.85, a mean bias μ of -0.06 ppm, and a standard deviation σ of 0.45 ppm. TES exhibits an r2 of 0.75, μ of 0.34 ppm, and σ of 1.13 ppm. For AIRS, we find an r2 of 0.37, μ of 1.11 ppm, and σ of 1.46 ppm, with latitude-dependent biases. For these comparisons at least 6, 20, and 50 atmospheric soundings have been averaged for GOSAT, TES, and AIRS

  13. Self-Poling of BiFeO3 Thick Films.

    Science.gov (United States)

    Khomyakova, Evgeniya; Sadl, Matej; Ursic, Hana; Daniels, John; Malic, Barbara; Bencan, Andreja; Damjanovic, Dragan; Rojac, Tadej

    2016-08-01

    Bismuth ferrite (BiFeO3) is difficult to pole because of the combination of its high coercive field and high electrical conductivity. This problem is particularly pronounced in thick films. The poling, however, must be performed to achieve a large macroscopic piezoelectric response. This study presents evidence of a prominent and reproducible self-poling effect in few-tens-of-micrometer-thick BiFeO3 films. Direct and converse piezoelectric measurements confirmed that the as-sintered BiFeO3 thick films yield d33 values of up to ∼20 pC/N. It was observed that a significant self-poling effect only appears in cases when the films are heated and cooled through the ferroelectric-paraelectric phase transition (Curie temperature TC ∼ 820 °C). These self-poled films exhibit a microstructure with randomly oriented columnar grains. The presence of a compressive strain gradient across the film thickness cooled from above the TC was experimentally confirmed and is suggested to be responsible for the self-poling effect. Finally, the macroscopic d33 response of the self-poled BiFeO3 film was characterized as a function of the driving-field frequency and amplitude.

  14. New Early Paleozoic Paleomagnetic Poles From NW Argentina: a Reappraisal of Tectonic Models

    Science.gov (United States)

    Spagnuolo, C. M.; Rapalini, A. E.; Astini, R. A.

    2007-05-01

    A paleomagnetic study carried out on Early Ordovician volcanic units in the Famatina Ranges of NW Argentina yielded a pre-tectonic paleomagnetic pole at 32.7°S, 4.3°E, (5.6°/ 8.6°, N=14 sites) that is consistent with four previous Early Ordovician poles from the Famatina - Eastern Puna Eruptive Belt of NW Argentina. However, these five poles are rotated around 50° clockwise respect to the coeval reference pole of Gondwana. Our new results seem to confirm previous models of this belt as a paraauthocthonous rotated terrane on the southwestern margin of Gondwana. However, a recent paleomagnetic pole from the Late Cambrian Mesón Group, at the Eastern Cordillera of NW Argentina, corresponding to the Gondwana foreland (4.5°S, 359.0°E, dp=5.5°, dm=8.8°, n=26 samples) and preliminary paleopoles obtained from the same unit and the latest Cambrian - Early Ordovician Santa Victoria Group at other three localities in the same region, also indicate an anomalous pole position rotated some 40° clockwise respect to the reference pole for Gondwana. These results suggest that the postulated model of a rotated terrane for the Famatina-Eastern Puna belt must be reconsidered. Different alternative scenarios including the possibility of an Early Paleozoic displacement of the whole basement of the Eastern Sierras Pampeanas of Argentina ("Pampia") will be explored.

  15. The effect of dc poling duration on space charge relaxation in virgin XLPE cable peelings

    Science.gov (United States)

    Tzimas, Antonios; Rowland, Simon M.; Dissado, Leonard A.; Fu, Mingli; Nilsson, Ulf H.

    2010-06-01

    The effect of dc poling time upon the time-dependent decay of space charge in insulation peelings of cross-linked polyethylene (XLPE) cable that had not previously experienced either electrical or thermal stressing is investigated. Two dc poling durations were used, 2 h and 26 h at an electric field of 50 kV mm-1 and at ambient temperature. Space charge was measured in the two samples investigated both during space charge accumulation and throughout its subsequent decay. The results show that the length of dc poling plays an important role in the subsequent decay. Despite the fact that both samples have had the same amount of space charge by the end of both short and long poling durations the time dependence of the space charge decay is different. Most of the charge stored in the sample that had experienced the short time poling decays rapidly after voltage removal. On the other hand, the charge that is stored in the sample with the long dc poling duration decays slowly and its decay occurs in two stages. The data, which are analysed by means of the de-trapping theory of space charge decay, imply that the charge stored in the material has occupied energy states with different trap depth ranges. The two poling durations lead to different relative amounts of charge in each of the two trap depth ranges. Possible reasons for this are discussed.

  16. South Africa

    DEFF Research Database (Denmark)

    Brixen, Peter; Tarp, Finn

    1996-01-01

    This paper explores the macroeconomic situation and medium-term perspectives of the South African economy. Three fully quantified and internally consistent scenarios are presented. The projections demonstrate that there is room for increased public spending in real terms to help address South...... Africa's pressing social needs. Moreover, such expansion is possible without falling into a much feared debt trap, provided moderately optimistic assumptions about the future materialize. Yet, if growth and real resource inflows falter, not even considerable moderation will be sufficient to maintain...

  17. Pole coordinates of the asteroid 511 Davida as determined via the amplitude-magnitude method

    Science.gov (United States)

    Zappala, V.; Knezevic, Z.

    1986-01-01

    The Amplitude-Magnitude method is used for the pole determination of the asteroid 511 Davida, using observations from six oppositions. The possible north poles are found to be λ1 = 92°±7°; β1 = 33°±6°, and λ2 = 303°±4°; β2 = 34°±5°, when scattering effect is not taken into account. When scattering is accounted for, solutions not significantly different from (λ1, β1) and (λ2, β2) are obtained. The moderately eccentric and inclined orbit of 511 Davida does not allow the authors to distinguish between the two pole solutions.

  18. Raman probes based on optically-poled double-clad fiber and coupler

    DEFF Research Database (Denmark)

    Brunetti, Anna Chiara; Margulis, Walter; Rottwitt, Karsten

    2012-01-01

    Two fiber Raman probes are presented, one based on an optically-poled double-clad fiber and the second based on an optically-poled double-clad fiber coupler respectively. Optical poling of the core of the fiber allows for the generation of enough 532nm light to perform Raman spectroscopy...... of a sample of dimethyl sulfoxide (DMSO), when illuminating the waveguide with 1064nm laser light. The Raman signal is collected in the inner cladding, from which it is retrieved with either a bulk dichroic mirror or a double-clad fiber coupler. The coupler allows for a substantial reduction of the fiber...

  19. Frequent POLE1 p.S297F mutation in Chinese patients with ovarian endometrioid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Yang; Liu, Fa-Ying; Liu, Huai; Wang, Feng [Key Laboratory of Women' s Reproductive Health of Jiangxi Province, Jiangxi Provincial Maternal and Child Health Hospital, Nanchang, Jiangxi 330006 (China); Central Laboratory, Jiangxi Provincial Maternal and Child Health Hospital, Nanchang, Jiangxi 330006 (China); Li, Wei [Key Laboratory of Women' s Reproductive Health of Jiangxi Province, Jiangxi Provincial Maternal and Child Health Hospital, Nanchang, Jiangxi 330006 (China); Central Laboratory, Jiangxi Provincial Maternal and Child Health Hospital, Nanchang, Jiangxi 330006 (China); Graduate School of Nanchang University, Nanchang, Jiangxi 330031 (China); Huang, Mei-Zhen [Graduate School of Nanchang University, Nanchang, Jiangxi 330031 (China); Jiangxi Provincial Cancer Institute, Jiangxi Provincial Cancer Hospital, Nanchang, Jiangxi 330029 (China); Huang, Yan; Yuan, Xiao-Qun [Key Laboratory of Women' s Reproductive Health of Jiangxi Province, Jiangxi Provincial Maternal and Child Health Hospital, Nanchang, Jiangxi 330006 (China); Central Laboratory, Jiangxi Provincial Maternal and Child Health Hospital, Nanchang, Jiangxi 330006 (China); Graduate School of Nanchang University, Nanchang, Jiangxi 330031 (China); Xu, Xiao-Yun [Graduate School of Nanchang University, Nanchang, Jiangxi 330031 (China); Jiangxi Provincial Cancer Institute, Jiangxi Provincial Cancer Hospital, Nanchang, Jiangxi 330029 (China); Huang, Ou-Ping, E-mail: huangouping@gmail.com [Jiangxi Provincial Cancer Institute, Jiangxi Provincial Cancer Hospital, Nanchang, Jiangxi 330029 (China); He, Ming, E-mail: jxhm56@hotmail.com [Department of Pharmacology and Molecular Therapeutics, Nanchang University School of Pharmaceutical Science, Nanchang 330006 (China)

    2014-03-15

    The catalytic subunit of DNA polymerase epsilon (POLE1) functions primarily in nuclear DNA replication and repair. Recently, POLE1 mutations were detected frequently in colorectal and endometrial carcinomas while with lower frequency in several other types of cancer, and the p.P286R and p.V411L mutations were the potential mutation hotspots in human cancers. Nevertheless, the mutation frequency of POLE1 in ovarian cancer still remains largely unknown. Here, we screened a total of 251 Chinese samples with distinct subtypes of ovarian carcinoma for the presence of POLE1 hotspot mutations by direct sequencing. A heterozygous somatic POLE1 mutation, p.S297F (c.890C>T), but not p.P286R and p.V411L hotspot mutations observed in other cancer types, was identified in 3 out of 37 (8.1%) patients with ovarian endometrioid carcinoma; this mutation was evolutionarily highly conserved from Homo sapiens to Schizosaccharomyces. Of note, the POLE1 mutation coexisted with mutation in the ovarian cancer-associated PPP2R1A (protein phosphatase 2, regulatory subunit A, α) gene in a 46-year-old patient, who was also diagnosed with ectopic endometriosis in the benign ovary. In addition, a 45-year-old POLE1-mutated ovarian endometrioid carcinoma patient was also diagnosed with uterine leiomyoma while the remaining 52-year-old POLE1-mutated patient showed no additional distinctive clinical manifestation. In contrast to high frequency of POLE1 mutations in ovarian endometrioid carcinoma, no POLE1 mutations were identified in patients with other subtypes of ovarian carcinoma. Our results showed for the first time that the POLE1 p.S297F mutation, but not p.P286R and p.V411L hotspot mutations observed in other cancer types, was frequent in Chinese ovarian endometrioid carcinoma, but absent in other subtypes of ovarian carcinoma. These results implicated that POLE1 p.S297F mutation might be actively involved in the pathogenesis of ovarian endometrioid carcinoma, but might not be actively

  20. Frequent POLE1 p.S297F mutation in Chinese patients with ovarian endometrioid carcinoma

    International Nuclear Information System (INIS)

    The catalytic subunit of DNA polymerase epsilon (POLE1) functions primarily in nuclear DNA replication and repair. Recently, POLE1 mutations were detected frequently in colorectal and endometrial carcinomas while with lower frequency in several other types of cancer, and the p.P286R and p.V411L mutations were the potential mutation hotspots in human cancers. Nevertheless, the mutation frequency of POLE1 in ovarian cancer still remains largely unknown. Here, we screened a total of 251 Chinese samples with distinct subtypes of ovarian carcinoma for the presence of POLE1 hotspot mutations by direct sequencing. A heterozygous somatic POLE1 mutation, p.S297F (c.890C>T), but not p.P286R and p.V411L hotspot mutations observed in other cancer types, was identified in 3 out of 37 (8.1%) patients with ovarian endometrioid carcinoma; this mutation was evolutionarily highly conserved from Homo sapiens to Schizosaccharomyces. Of note, the POLE1 mutation coexisted with mutation in the ovarian cancer-associated PPP2R1A (protein phosphatase 2, regulatory subunit A, α) gene in a 46-year-old patient, who was also diagnosed with ectopic endometriosis in the benign ovary. In addition, a 45-year-old POLE1-mutated ovarian endometrioid carcinoma patient was also diagnosed with uterine leiomyoma while the remaining 52-year-old POLE1-mutated patient showed no additional distinctive clinical manifestation. In contrast to high frequency of POLE1 mutations in ovarian endometrioid carcinoma, no POLE1 mutations were identified in patients with other subtypes of ovarian carcinoma. Our results showed for the first time that the POLE1 p.S297F mutation, but not p.P286R and p.V411L hotspot mutations observed in other cancer types, was frequent in Chinese ovarian endometrioid carcinoma, but absent in other subtypes of ovarian carcinoma. These results implicated that POLE1 p.S297F mutation might be actively involved in the pathogenesis of ovarian endometrioid carcinoma, but might not be actively

  1. Poles, the only true resonant-state signals, are extracted from a worldwide collection of partial wave amplitudes using only one, well controlled pole-extraction method

    CERN Document Server

    Hadžimehmedović, M; Švarc, A; Osmanović, H; Stahov, J

    2011-01-01

    Each and every energy dependent partial-wave analysis is parameterizing the pole positions in a procedure defined by the way how the continuous energy dependence is implemented. These pole positions are, henceforth, inherently model dependent. To reduce this model dependence, we use only one, coupled-channel, unitary, fully analytic method based on the isobar approximation to extract the pole positions from the each available member of the worldwide collection of partial wave amplitudes which are understood as nothing more but a good energy dependent representation of genuine experimental numbers assembled in a form of partial-wave data. In that way, the model dependence related to the different assumptions on the analytic form of the partial-wave amplitudes is avoided, and the true confidence limit for the existence of a particular resonant state, at least in one model, is established. The way how the method works, and first results are demonstrated for the S11 partial wave.

  2. Libration celestial mechanics experiment

    Science.gov (United States)

    Andreev, O. N.; Antonenko, S. A.; Gotlib, V. M.; Zakharkin, G. V.; Linkin, V. M.; Lipatov, A. N.; Makarov, V. S.; Khairulin, B. K.; Khlyustova, L. I.

    2010-10-01

    The exploration of planet moons and minor bodies (Avduevskii et al., 1996) is a basic task for comprehending the nature of the processes occurring in our Solar System. Knowing the current state of the moons, we can better describe their past and look into the future. This knowledge is important, first of all, for understanding the origin of the Solar System. Interest in the Martian moon Phobos has been displayed during recent decades. The interest is caused by some questions to which there have been no answers up until now (Sagdeev et al., 1988; 1989). For example, there is a question regarding the origin of the moon: whether it is an asteroid captured by Mars’ gravitational field or it is an accumulated body in the Martian orbit. In connection with this, it is interesting to conduct studies aimed at answering this question. If Phobos appears to be an asteroid, then investigations regarding the chemical and isotopic compositions of the moon as the primary matter of the Solar System as well as its evolution are of great interest. As of today, we know that Phobos orbits 9400 km from the center of Mars, with the speed of its revolution being so great that it makes one revolution every one-third of a Martian day (7 h 39 min), outrunning the daily spin of Mars. The strong tidal friction occurring due to the Phobos’ position close to Mars reduces the energy of its motion. The moon is slowly approaching the planet’s surface and will make impact with it eventually (this should happen over the course of 100 million years) if by that time Mars’ gravitational field does not tear it to pieces (this should happen over the course of 50 million years). Phobos is an elongated body with dimensions of 27 × 22× 18.6 km. The measurements of the spectral characteristics performed during the Phobos-2 mission (Ksanformality, Moroz, 1995) have indicated that the reflection spectra of Phobos and Deimos differ substantially from those obtained in observations of Mars, as well as from the spectra of carbonaceous chondrites and other asteroid analogs. The latest scientific results demonstrate that the Martian moons most likely belong to class-D asteroids, although the analogy is not perfect. The results of measuring the reflection characteristics display no bound water on the surface of the Martian moons. However, there are estimations, according to which the thermodynamic conditions on these moons are such that water may stay at a certain depth. Clarifying the issue regarding the presence of water (or hydrated molecules) on Phobos is very important not only from the scientific standpoint, but also from the practical one. Phobos is subject to a strong tidal effect by Mars; therefore, it always keeps the same side turned towards Mars. In connection with this, one of the most interesting characteristics of Phobos is libration. Phobos is a very amazing object among the known synchronously orbiting moons of the planets of the Solar System because it has a large amplitude of libration. The libration effect is always present in a several-body system.

  3. THE ATACAMA COSMOLOGY TELESCOPE: PHYSICAL PROPERTIES OF SUNYAEV-ZEL'DOVICH EFFECT CLUSTERS ON THE CELESTIAL EQUATOR {sup ,}

    Energy Technology Data Exchange (ETDEWEB)

    Menanteau, Felipe; Hughes, John P. [Department of Physics and Astronomy, Rutgers University, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Sifon, Cristobal; Barrientos, L. Felipe; Duenner, Rolando; Infante, Leopoldo [Departamento de Astronomia y Astrofisica, Facultad de Fisica, Pontificia Universidad Catolica de Chile, Casilla 306, Santiago 22 (Chile); Battaglia, Nicholas [McWilliams Center for Cosmology, Department of Physics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213 (United States); Bond, J. Richard; Hajian, Amir; Hincks, Adam D. [Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, ON M5S 3H8 (Canada); Crichton, Devin; Gralla, Megan; Marriage, Tobias A. [Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, MD 21218-2686 (United States); Das, Sudeep [High Energy Physics Division, Argonne National Laboratory, 9700 S Cass Avenue, Lemont, IL 60439 (United States); Devlin, Mark J.; Dicker, Simon [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States); Hasselfield, Matthew [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z4 (Canada); Hilton, Matt [Astrophysics and Cosmology Research Unit, School of Mathematics, Statistics and Computer Science, University of KwaZulu-Natal, Durban (South Africa); Kosowsky, Arthur [Physics and Astronomy Department, University of Pittsburgh, 100 Allen Hall, 3941 O' Hara Street, Pittsburgh, PA 15260 (United States); Marsden, Danica [Department of Physics, University of California Santa Barbara, CA 93106 (United States); and others

    2013-03-01

    We present the optical and X-ray properties of 68 galaxy clusters selected via the Sunyaev-Zel'dovich (SZ) effect at 148 GHz by the Atacama Cosmology Telescope (ACT). Our sample, from an area of 504 deg{sup 2} centered on the celestial equator, is divided into two regions. The main region uses 270 deg{sup 2} of the ACT survey that overlaps with the co-added ugriz imaging from the Sloan Digital Sky Survey (SDSS) over Stripe 82 plus additional near-infrared pointed observations with the Apache Point Observatory 3.5 m telescope. We confirm a total of 49 clusters to z Almost-Equal-To 1.3, of which 22 (all at z > 0.55) are new discoveries. For the second region, the regular-depth SDSS imaging allows us to confirm 19 more clusters up to z Almost-Equal-To 0.7, of which 10 systems are new. We present the optical richness, photometric redshifts, and separation between the SZ position and the brightest cluster galaxy (BCG). We find no significant offset between the cluster SZ centroid and BCG location and a weak correlation between optical richness and SZ-derived mass. We also present X-ray fluxes and luminosities from the ROSAT All Sky Survey which confirm that this is a massive sample. One of the newly discovered clusters, ACT-CL J0044.4+0113 at z = 1.1 (photometric), has an integrated XMM-Newton X-ray temperature of kT{sub X} = 7.9 {+-} 1.0 keV and combined mass of M {sub 200a} = 8.2{sup +3.3} {sub -2.5} Multiplication-Sign 10{sup 14} h {sup -1} {sub 70} M {sub Sun }, placing it among the most massive and X-ray-hot clusters known at redshifts beyond z = 1. We also highlight the optically rich cluster ACT-CL J2327.4-0204 (RCS2 2327) at z = 0.705 (spectroscopic) as the most significant detection of the whole equatorial sample with a Chandra-derived mass of M {sub 200a} = 1.9{sup +0.6} {sub -0.4} Multiplication-Sign 10{sup 15} h {sup -1} {sub 70} M {sub Sun }, placing it in the ranks of the most massive known clusters like El Gordo and the Bullet Cluster.

  4. Saturated South

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Heavy rain produced the worst floods in a century in some areas of China causing deaths and forcing whole communities to evacuate Millions have been forced to flee their homes in south China amid floods caused by heavy rainfall since the end of May.

  5. [South] Korea.

    Science.gov (United States)

    1987-04-01

    The Republic of Korea occupies approximately 38,000 square miles in the southern position of a mountaineous peninsula. It shares a land boundary with North Korea. With a population of more than 40 million people, South Korea has 1 of the highest population densities in the world. The language spoken is a Uralic language, closely akin to Japanese, Hungarian, Finnish, and Mongolian, and the traditional religions are Shamanism and Buddhism. Over the course of time, South Korea has been invaded and fought over by its neighbors. The US and the Soviet Union have never been able to reach a unification agreement for North and South Korea. The 3rd Republic era, begun in 1963, saw a time of rapid industrialization and a great deal of economic growth. The 5th Republic began with a new constitution and new elections brought about the election of a president to a 7-year term of office beginning in 1981. Economic growth has been remarkable over the last 25 years despite the fact that North Korea possesses most of the mineral and hydroelectric resources and the existing heavy industrial base built by the Japanese while South Korea has the limited agricultural resources and had, initially, a large unskilled labor pool. Serious industrial growth began in South Korea in the early 1960s and the GNP grew at an annual rate of 10% during the period 1963-78. Current GNP is now, at $2000, well beyond that of its neighbors to the north. The outlook for longterm growth is good; however, the military threat posed by North Korea and the absence of foreign economic assistance has resulted in Korea spending 1/3 of its budget on defense. South Korea is active in international affairs and in the UN. Economic realities have forced Korea to give economics priority in their foreign policy. There has been an on-again, off-again quality to dialogue between the 2 nations. However, the US is committed to maintaining peace on the Korean peninsula. In order to do so, they have supplied manpower and

  6. Application of Corona Discharge for Poling Ferroelectric and Nonlinear Optical Polymers

    OpenAIRE

    Fedosov, S. N.; Sergeeva, A. E.; Revenyuk, T. A.; Butenko, A. F.

    2007-01-01

    Four modifications of the corona triode are described for charging polar polymers with ferroelectric or non-linear optical properties. Advantages of the constant current modification of corona poling are illustrated and discussed.

  7. Discontinuous behaviour of polarization angular parameters at the poles of Poincare sphere

    Science.gov (United States)

    Bieg, B.; Chrzanowski, J.; Kravcov, Yu. A.

    2012-01-01

    The behavior of four angular parameters describing polarization ellipse is analyzed in the vicinity of Poincare sphere poles. It is shown that the phenomenon of step-wise change of azimuthal angle of polarization ellipse at π/2 near poles s3 = ±1 is not accompanied by discontinuities in other parameters of polarization ellipse. In particular the dual system of angular parameters "amplitude-ratio angle and phase difference" do not experience any discontinuities near the poles s3 = ±1. The same is true for the area of polarization ellipse, which is shown to be continuous on the whole Poincare sphere. Analogously, step-wise change of phase difference at π near poles s1 = ±1 is not accompanied by any discontinuities in basic system of angular parameters "azimuth-ellipticity". General features of angular parameters behavior are illustrated by the results of numerical modelling.

  8. Comparison of novel liquid electrodes for silica optical fiber thermal poling

    OpenAIRE

    De Lucia, Francesco; Corbari, Costantino; Keefer, Derek; Sazio, Pier-John

    2016-01-01

    We report experimental analysis of optical fibers thermally poled over long lengths using novel types of internal liquid electrodes to generate effective second-order nonlinearities. Our analysis includes transmission losses, depletion region formation, SHG at telecom pump wavelengths.

  9. Lowering the pump power requirement for squeezed light generation using a periodically poled crystal

    DEFF Research Database (Denmark)

    Andersen, Ulrik Lund; Buchhave, Preben

    2003-01-01

    Observations of continuous wave bright squeezed light from an intra-cavity periodically poled KTP second harmonic generator are presented. The experiment includes characterization of the classical as well as the quantum properties of the system....

  10. Cassini Returns to Saturn's Poles: Seasonal Change in the Polar Vortices

    Science.gov (United States)

    Fletcher, Leigh N.; Orton, G. S.; Irwin, P. G. J.; Sinclair, J. A.; Hesman, B. E.; Hurley, J.; Bjoraker, G. L.; Simon-Miller, A. A.

    2013-01-01

    High inclination orbits during Cassini's solstice mission (2012) are providing us with our first observations of Saturn's high latitudes since the prime mission (2007). Since that time, the northern spring pole has emerged into sunlight and the southern autumn pole has disappeared into winter darkness, allowing us to study the seasonal changes occurring within the polar vortices in response to these dramatic insolation changes. Observations from the Cassini Composite Infrared Spectrometer] have revealed (i) the continued presence of small, cyclonic polar hotspots at both spring and autumn poles; and (ii) the emergence of an infrared-bright polar vortex at the north pole, consistent with the historical record of Saturn observations from the 1980s (previous northern spring).

  11. 76 FR 4078 - Television Broadcasting Services; North Pole and Plattsburgh, NY

    Science.gov (United States)

    2011-01-24

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 73 Television Broadcasting Services; North Pole and Plattsburgh, NY AGENCY: Federal... CFR Part 73 Television, Television broadcasting. For the reasons discussed in the preamble,...

  12. Duality between zeroes and poles in holographic systems with massless fermions and a dipole coupling

    CERN Document Server

    Alsup, James; Siopsis, George; Yeter, Kubra

    2014-01-01

    We discuss the zeroes and poles of the determinant of the retarded Green function ($\\det G_R$) at zero frequency in a holographic system of charged massless fermions interacting via a dipole coupling. For large negative values of the dipole coupling constant $p$, $\\det G_R$ possesses only poles pointing to a Fermi liquid phase. We show that a duality exists relating systems of opposite $p$. This maps poles of $\\det G_R$ at large negative $p$ to zeroes of $\\det G_R$ at large positive $p$, indicating that the latter corresponds to a Mott insulator phase. This duality suggests that the properties of a Mott insulator can be studied by mapping the system to a Fermi liquid. Finally, for small values of $p$, $\\det G_R$ contains both poles and zeroes (pseudo-gap phase).

  13. On the pole content of coupled channels chiral approaches used for the K bar N system

    Science.gov (United States)

    Cieplý, A.; Mai, M.; Meißner, Ulf-G.; Smejkal, J.

    2016-10-01

    Several theoretical groups describe the antikaon-nucleon interaction at low energies within approaches based on the chiral SU(3) dynamics and including next-to-leading order contributions. We present a comparative analysis of the pertinent models and discuss in detail their pole contents. It is demonstrated that the approaches lead to very different predictions for the K- p amplitude extrapolated to subthreshold energies as well as for the K- n amplitude. The origin of the poles generated by the models is traced to the so-called zero coupling limit, in which the inter-channel couplings are switched off. This provides new insights into the pole contents of the various approaches. In particular, different concepts of forming the Λ (1405) resonance are revealed and constraints related to the appearance of such poles in a given approach are discussed.

  14. Transmission Lines or Poles, Electric, electric transmission line, Published in unknown, Kleinschmidt.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset as of unknown. It is described as 'electric transmission line'. Data by this publisher are often provided in UTM...

  15. REGION NORTH OF TEACHER EDUCATION POLICY AND EVALUATION OF POLES OPEN UNIVERSITY SYSTEM OF BRAZIL

    Directory of Open Access Journals (Sweden)

    Celso José da Costa

    2013-03-01

    Full Text Available This text aims to present, in general, the north region and policies for teacher training implemented in the last 5 years, locating in this context the importance of the Brazil Open University system and its supporting poles face as methodology research linked to the project "Institutionalization of Distance Education in Brazil." Greater emphasis will be given to data from the states of Pará and Acre, given that two authors of this text act as coordinators of the poles supporting attendance System Open University of Brazil in these states. We design the text, based on testimony of poles coordinators who participated in participatory research, conducted by the Research Group "Teacher education and information and communication technologies", LANTE / UFF. We aim also to identify the structure and functioning of the Poles face Supporting UAB in the North as well as the assessment tool applied in this region.

  16. Relation Between the Pole Mass and MS Mass of Top Quark in Supersymmetric QCD

    Institute of Scientific and Technical Information of China (English)

    CHEN Shao-Long; FENG Tai-Fu; LI Xue-Qian

    2001-01-01

    We discuss the relation between the pole mass and MS mass of top quark in the framework of the supersymmetric QCD. We find that the supersymmetric contributions are comparable to those of the standard model.

  17. Transmission Lines or Poles, Electric, IPPCalifLine, Published in 2008, Millard County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, was produced all or in part from Other information as of 2008. It is described as 'IPPCalifLine'. Data by this...

  18. Transmission Lines or Poles, Electric, IPPMonaLine, Published in 2007, Millard County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, was produced all or in part from Other information as of 2007. It is described as 'IPPMonaLine'. Data by this...

  19. Transmission Lines or Poles, Electric, UtilityCorridor, Published in 2008, Millard County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, was produced all or in part from Other information as of 2008. It is described as 'UtilityCorridor'. Data by...

  20. Pahane Berlusconi : pole ma teile mingi kääbus / Aadu Hiietamm

    Index Scriptorium Estoniae

    Hiietamm, Aadu, 1954-

    2008-01-01

    Aprillis toimuvate parlamendivalimiste võidus täiesti kindel olev Itaalia ekspeaminister Silvio Berlusconi pole rahul karikatuuridega, mis rõhutavad ta lühikest kasvu. Vt. samas: Soovitus: teenige rohkem!