Science.gov

Sample records for observatory surface detector

  1. The Surface Detector System of the Pierre Auger Observatory

    SciTech Connect

    Allekotte, I.; Barbosa, A.F.; Bauleo, P.; Bonifazi, C.; Civit, B.; Escobar, C.O.; Garcia, B.; Guedes, G.; Gomez Berisso, M.; Harton, J.L.; Healy, M.; /Cuyo U. /Buenos Aires, CONICET /Natl. Tech. U., San Rafael /Campinas State U. /UEFS, Feira de Santana /Bahia U. /BUAP, Puebla /Santiago de Compostela U. /Fermilab /UCLA /Colorado State U.

    2007-11-01

    The Pierre Auger Observatory is designed to study cosmic rays with energies greater than 10{sup 19} eV. Two sites are envisaged for the observatory, one in each hemisphere, for complete sky coverage. The southern site of the Auger Observatory, now approaching completion in Mendoza, Argentina, features an array of 1600 water-Cherenkov surface detector stations covering 3000 km{sup 2}, together with 24 fluorescence telescopes to record the air shower cascades produced by these particles. The two complementary detector techniques together with the large collecting area form a powerful instrument for these studies. Although construction is not yet complete, the Auger Observatory has been taking data stably since January 2004 and the first physics results are being published. In this paper we describe the design features and technical characteristics of the surface detector stations of the Pierre Auger Observatory.

  2. New electronics for the surface detectors of the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Kleifges, M.

    2016-07-01

    The Pierre Auger Observatory is the largest installation worldwide for the investigation of ultra-high energy cosmic rays. Air showers are detected using a hybrid technique with 27 fluorescence telescopes and 1660 water-Cherenkov detectors (WCD) distributed over about 3000 km2. The Auger Collaboration has decided to upgrade the electronics of the WCD and complement the surface detector with scintillators (SSD). The objective is to improve the separation between the muonic and the electron/photon shower component for better mass composition determination during an extended operation period of 8-10 years. The surface detector electronics records data locally and generates time stamps based on the GPS timing. The performance of the detectors is significantly improved with a higher sampling rate, an increased dynamic range, new generation of GPS receivers, and FPGA integrated CPU power. The number of analog channels will be increased to integrate the new SSD, but the power consumption needs to stay below 10 W to be able to use the existing photovoltaic system. In this paper, the concept of the additional SSD is presented with a focus on the design and performance of the new surface detector electronics.

  3. Timing calibration and synchronization of surface and fluorescence detectors of the Pierre Auger Observatory

    SciTech Connect

    Allison, P.; Bellido, J.; Bertou, Xavier; Covault, C.E.; Fick, B.E.; Gemmeke, H.; Kleifges, M.; Mostafa, M.; Menshikov, A.; Meyer, F.; Pryke, C.; Sommers, P.; Vanderpan, E.; Vernotte, F.; Wiencke, L.

    2005-08-01

    Reconstruction of cosmic ray arrival directions for Surface Detectors (SD) and Fluorescence Detectors (FD) of the Pierre Auger Observatory requires accurate timing (25 nanoseconds or better) between measurements at individual detectors and instrument triggers. Timing systems for both SD and FD are based on Motorola Oncore UT+ GPS receivers installed into custom-built time-tagging circuits that are calibrated in the laboratory to a statistical precision of better than 15 ns. We describe timing calibration and synchronization methods applied in the field for both the SD and the FD systems in four areas: (1) checks of timing offsets within the SD using co-located station pairs and timing residuals on reconstructed showers, (2) calibration within the FD using a custom-build LED calibration system, (3) calibration between SD and FD using laser signals fed simultaneously into an SD station and across the FD via the Central Laser Facility (CLF), and (4) studies of synchronization between FD and SD through the analysis of events detected by both systems, called hybrid events. These hybrid events allow for a much more accurate reconstruction of the shower and for relatively tight constraints on timing calibration offsets. We demonstrate that statistical and systematic timing uncertainties have no significant impact on the event reconstruction.

  4. Azimuthal asymmetry in the risetime of the surface detector signals of the Pierre Auger Observatory

    DOE PAGES

    Aab, Alexander

    2016-04-07

    The azimuthal asymmetry in the risetime of signals in Auger surface detector stations is a source of information on shower development. The azimuthal asymmetry is due to a combination of the longitudinal evolution of the shower and geometrical effects related to the angles of incidence of the particles into the detectors. The magnitude of the effect depends upon the zenith angle and state of development of the shower and thus provides a novel observable, (secθ)max, sensitive to the mass composition of cosmic rays above 3 x 1018 eV. By comparing measurements with predictions from shower simulations, we find for bothmore » of our adopted models of hadronic physics (QGSJETII-04 and EPOS-LHC) an indication that the mean cosmic-ray mass increases slowly with energy, as has been inferred from other studies. However, the mass estimates are dependent on the shower model and on the range of distance from the shower core selected. Furthermore, the method has uncovered further deficiencies in our understanding of shower modelling that must be resolved before the mass composition can be inferred from (secθ)max.« less

  5. Azimuthal asymmetry in the risetime of the surface detector signals of the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Aab, A.; Abreu, P.; Aglietta, M.; Ahn, E. J.; Al Samarai, I.; Albuquerque, I. F. M.; Allekotte, I.; Allison, P.; Almela, A.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Alves Batista, R.; Ambrosio, M.; Anchordoqui, L.; Andrada, B.; Andringa, S.; Aramo, C.; Arqueros, F.; Arsene, N.; Asorey, H.; Assis, P.; Aublin, J.; Avila, G.; Awal, N.; Badescu, A. M.; Baus, C.; Beatty, J. J.; Becker, K. H.; Bellido, J. A.; Berat, C.; Bertaina, M. E.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blaess, S. G.; Blanco, A.; Blazek, J.; Bleve, C.; Blümer, H.; Boháčová, M.; Boncioli, D.; Bonifazi, C.; Borodai, N.; Botti, A. M.; Brack, J.; Brancus, I.; Bretz, T.; Bridgeman, A.; Briechle, F. L.; Buchholz, P.; Bueno, A.; Buitink, S.; Buscemi, M.; Caballero-Mora, K. S.; Caccianiga, B.; Caccianiga, L.; Cancio, A.; Candusso, M.; Caramete, L.; Caruso, R.; Castellina, A.; Cataldi, G.; Cazon, L.; Cester, R.; Chavez, A. G.; Chiavassa, A.; Chinellato, J. A.; Chirinos Diaz, J. C.; Chudoba, J.; Clay, R. W.; Colalillo, R.; Coleman, A.; Collica, L.; Coluccia, M. R.; Conceição, R.; Contreras, F.; Cooper, M. J.; Coutu, S.; Covault, C. E.; Cronin, J.; Dallier, R.; D'Amico, S.; Daniel, B.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; de Jong, S. J.; De Mauro, G.; de Mello Neto, J. R. T.; De Mitri, I.; de Oliveira, J.; de Souza, V.; Debatin, J.; Deligny, O.; Dhital, N.; Di Giulio, C.; Di Matteo, A.; Díaz Castro, M. L.; Diogo, F.; Dobrigkeit, C.; Docters, W.; D'Olivo, J. C.; Dorofeev, A.; dos Anjos, R. C.; Dova, M. T.; Dundovic, A.; Ebr, J.; Engel, R.; Erdmann, M.; Erfani, M.; Escobar, C. O.; Espadanal, J.; Etchegoyen, A.; Falcke, H.; Fang, K.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Fick, B.; Figueira, J. M.; Filevich, A.; Filipčič, A.; Fratu, O.; Freire, M. M.; Fujii, T.; Fuster, A.; Gallo, F.; García, B.; Garcia-Pinto, D.; Gate, F.; Gemmeke, H.; Gherghel-Lascu, A.; Ghia, P. L.; Giaccari, U.; Giammarchi, M.; Giller, M.; Głas, D.; Glaser, C.; Glass, H.; Golup, G.; Gómez Berisso, M.; Gómez Vitale, P. F.; González, N.; Gookin, B.; Gordon, J.; Gorgi, A.; Gorham, P.; Gouffon, P.; Griffith, N.; Grillo, A. F.; Grubb, T. D.; Guarino, F.; Guedes, G. P.; Hampel, M. R.; Hansen, P.; Harari, D.; Harrison, T. A.; Harton, J. L.; Hasankiadeh, Q.; Haungs, A.; Hebbeker, T.; Heck, D.; Heimann, P.; Herve, A. E.; Hill, G. C.; Hojvat, C.; Hollon, N.; Holt, E.; Homola, P.; Hörandel, J. R.; Horvath, P.; Hrabovský, M.; Huege, T.; Insolia, A.; Isar, P. G.; Jandt, I.; Jansen, S.; Jarne, C.; Johnsen, J. A.; Josebachuili, M.; Kääpä, A.; Kambeitz, O.; Kampert, K. H.; Kasper, P.; Katkov, I.; Keilhauer, B.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Krause, R.; Krohm, N.; Kuempel, D.; Kukec Mezek, G.; Kunka, N.; Kuotb Awad, A.; LaHurd, D.; Latronico, L.; Lauscher, M.; Lautridou, P.; Lebrun, P.; Leigui de Oliveira, M. A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; Lopes, L.; López, R.; López Casado, A.; Lucero, A.; Malacari, M.; Mallamaci, M.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, V.; Mariş, I. C.; Marsella, G.; Martello, D.; Martinez, H.; Martínez Bravo, O.; Masías Meza, J. J.; Mathes, H. J.; Mathys, S.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mayotte, E.; Mazur, P. O.; Medina, C.; Medina-Tanco, G.; Mello, V. B. B.; Melo, D.; Menshikov, A.; Messina, S.; Micheletti, M. I.; Middendorf, L.; Minaya, I. A.; Miramonti, L.; Mitrica, B.; Molina-Bueno, L.; Mollerach, S.; Montanet, F.; Morello, C.; Mostafá, M.; Moura, C. A.; Müller, G.; Muller, M. A.; Müller, S.; Naranjo, I.; Navas, S.; Necesal, P.; Nellen, L.; Nelles, A.; Neuser, J.; Nguyen, P. H.; Niculescu-Oglinzanu, M.; Niechciol, M.; Niemietz, L.; Niggemann, T.; Nitz, D.; Nosek, D.; Novotny, V.; Nožka, H.; Núñez, L. A.; Ochilo, L.; Oikonomou, F.; Olinto, A.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Papenbreer, P.; Parente, G.; Parra, A.; Paul, T.; Pech, M.; Pekala, J.; Pelayo, R.; Peña-Rodriguez, J.; Pepe, I. M.; Pereira, L. A. S.; Perrone, L.; Petermann, E.; Peters, C.; Petrera, S.; Phuntsok, J.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.; Platino, M.; Plum, M.; Porowski, C.; Prado, R. R.; Privitera, P.; Prouza, M.; Quel, E. J.; Querchfeld, S.; Quinn, S.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Reinert, D.; Revenu, B.; Ridky, J.; Risse, M.; Ristori, P.; Rizi, V.; Rodrigues de Carvalho, W.; Rodriguez Rojo, J.; Rogozin, D.; Rosado, J.; Roth, M.; Roulet, E.; Rovero, A. C.; Saffi, S. J.; Saftoiu, A.; Salazar, H.; Saleh, A.; Salesa Greus, F.; Salina, G.; Sanabria Gomez, J. D.; Sánchez, F.; Sanchez-Lucas, P.; Santos, E. M.; Santos, E.; Sarazin, F.; Sarkar, B.; Sarmento, R.; Sarmiento-Cano, C.; Sato, R.; Scarso, C.; Schauer, M.; Scherini, V.; Schieler, H.; Schmidt, D.; Scholten, O.; Schoorlemmer, H.; Schovánek, P.; Schröder, F. G.; Schulz, A.; Schulz, J.; Schumacher, J.; Sciutto, S. J.; Segreto, A.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sigl, G.; Sima, O.; Śmiałkowski, A.; Šmída, R.; Snow, G. R.; Sommers, P.; Sonntag, S.; Sorokin, J.; Squartini, R.; Stanca, D.; Stanič, S.; Stapleton, J.; Stasielak, J.; Strafella, F.; Stutz, A.; Suarez, F.; Suarez Durán, M.; Sudholz, T.; Suomijärvi, T.; Supanitsky, A. D.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Taborda, O. A.; Tapia, A.; Tepe, A.; Theodoro, V. M.; Timmermans, C.; Todero Peixoto, C. J.; Tomankova, L.; Tomé, B.; Tonachini, A.; Torralba Elipe, G.; Torres Machado, D.; Travnicek, P.; Trini, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van Aar, G.; van Bodegom, P.; van den Berg, A. M.; van Vliet, A.; Varela, E.; Vargas Cárdenas, B.; Varner, G.; Vasquez, R.; Vázquez, J. R.; Vázquez, R. A.; Veberič, D.; Verzi, V.; Vicha, J.; Videla, M.; Villaseñor, L.; Vorobiov, S.; Wahlberg, H.; Wainberg, O.; Walz, D.; Watson, A. A.; Weber, M.; Weindl, A.; Wiencke, L.; Wilczyński, H.; Winchen, T.; Wittkowski, D.; Wundheiler, B.; Wykes, S.; Yang, L.; Yapici, T.; Yelos, D.; Yushkov, A.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zepeda, A.; Zimmermann, B.; Ziolkowski, M.; Zong, Z.; Zuccarello, F.; Pierre Auger Collaboration

    2016-04-01

    The azimuthal asymmetry in the risetime of signals in Auger surface detector stations is a source of information on shower development. The azimuthal asymmetry is due to a combination of the longitudinal evolution of the shower and geometrical effects related to the angles of incidence of the particles into the detectors. The magnitude of the effect depends upon the zenith angle and state of development of the shower and thus provides a novel observable, (sec θ )max , sensitive to the mass composition of cosmic rays above 3 ×1018 eV . By comparing measurements with predictions from shower simulations, we find for both of our adopted models of hadronic physics (QGSJETII-04 and EPOS-LHC) an indication that the mean cosmic-ray mass increases slowly with energy, as has been inferred from other studies. However, the mass estimates are dependent on the shower model and on the range of distance from the shower core selected. Thus the method has uncovered further deficiencies in our understanding of shower modeling that must be resolved before the mass composition can be inferred from (sec θ )max.

  6. Limit on the diffuse flux of ultrahigh energy tau neutrinos with the surface detector of the Pierre Auger Observatory

    SciTech Connect

    Abraham, J.; De La Vega, G.; Garcia, B.; Videla, M.; Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Conceicao, R.; Goncalves, P.; Pimenta, M.; Santo, C. E.; Tome, B.; Aglietta, M.; Bonino, R.; Castellina, A.; Chiavassa, A.; Fulgione, W.; Gorgi, A.; Lucero, A.

    2009-05-15

    Data collected at the Pierre Auger Observatory are used to establish an upper limit on the diffuse flux of tau neutrinos in the cosmic radiation. Earth-skimming {nu}{sub {tau}} may interact in the Earth's crust and produce a {tau} lepton by means of charged-current interactions. The {tau} lepton may emerge from the Earth and decay in the atmosphere to produce a nearly horizontal shower with a typical signature, a persistent electromagnetic component even at very large atmospheric depths. The search procedure to select events induced by {tau} decays against the background of normal showers induced by cosmic rays is described. The method used to compute the exposure for a detector continuously growing with time is detailed. Systematic uncertainties in the exposure from the detector, the analysis, and the involved physics are discussed. No {tau} neutrino candidates have been found. For neutrinos in the energy range 2x10{sup 17} eV

  7. Selection and reconstruction of very inclined air showers with the Surface Detector of the Pierre Auger Observatory

    SciTech Connect

    Newton, D.; /Santiago de Compostela U.

    2007-06-01

    The water-Cherenkov tanks of the Pierre Auger Observatory can detect particles at all zenith angles and are therefore well-suited for the study of inclined and horizontal air showers (60 degrees < {theta} < 90 degrees). Such showers are characterized by a dominance of the muonic component at ground, and by a very elongated and asymmetrical footprint which can even exhibit a lobular structure due to the bending action of the geomagnetic field. Dedicated algorithms for the selection and reconstruction of such events, as well as the corresponding acceptance calculation, have been set up on basis of muon maps obtained from shower simulations.

  8. Performance of the fluorescence detectors of the pierre auger observatory

    SciTech Connect

    Bellido, Jose A.; /Adelaide U.

    2005-08-01

    Fluorescence detectors of the Pierre Auger Observatory have been operating in a stable manner since January 2004. After a brief review of the physical characteristics of the detectors, the associated atmospheric monitoring, the calibration infrastructure and the detector aperture, we will describe the steps required for the reconstruction of fluorescence event data, with emphasis on the shower profile parameters and primary energy.

  9. Calibration of the Pierre Auger Observatory fluorescence detectors and the effect on measurements

    NASA Astrophysics Data System (ADS)

    Gookin, Ben

    The Pierre Auger Observatory is a high-energy cosmic ray observatory located in Malargue, Mendoza, Argentina. It is used to probe the highest energy particles in the Universe, with energies greater than 1018 eV, which strike the Earth constantly. The observatory uses two techniques to observe the air shower initiated by a cosmic ray: a surface detector composed of an array of more than 1600 water Cherenkov tanks covering 3000 km2, and 27 nitrogen fluorescence telescopes overlooking this array. The Cherenkov detectors run all the time and therefore have high statistics on the air showers. The fluorescence detectors run only on clear moonless nights, but observe the longitudinal development of the air shower and make a calorimetric measure of its energy. The energy measurement from the the fluorescence detectors is used to cross calibrate the surface detectors, and makes the measurements made by the Auger Observatory surface detector highly model-independent. The calibration of the fluorescence detectors is then of the utmost importance to the measurements of the Observatory. Described here are the methods of the absolute and multi-wavelength calibration of the fluorescence detectors, and improvements in each leading to a reduction in calibration uncertainties to 4% and 3.5%, respectively. Also presented here are the effects of introducing a new, and more detailed, multi-wavelength calibration on the fluorescence detector energy estimation and the depth of the air shower maximum measurement, leading to a change of 1+-0.03% in the absolute energy scale at 1018 eV, and a negligible change in the measurement on shower maximum.

  10. The water Cherenkov detectors of the HAWC Observatory

    NASA Astrophysics Data System (ADS)

    Longo, Megan; Mostafa, Miguel

    2012-10-01

    The High Altitude Water Cherenkov (HAWC) observatory is a very high-energy gamma-ray detector which is currently under construction at 4100 m in Sierra Negra, Mexico. The observatory will be composed of an array of 300 Water Cherenkov Detectors (WCDs). Each WCD consists of a 5 m tall by 7.3 m wide steel tank containing a hermetically sealed plastic bag, called a bladder, which is filled with 200,000 liters of purified water. The detectors are each equipped with four upward-facing photomultiplier tubes (PMTs), anchored to the bottom of the bladder. At Colorado State University (CSU) we have the only full-size prototype outside of the HAWC site. It serves as a testbed for installation and operation procedures for the HAWC observatory. The WCD at CSU has been fully operational since March 2011, and has several components not yet present at the HAWC site. In addition to the four HAWC position PMTs, our prototype has three additional PMTs, including one shrouded (dark) PMT. We also have five scintillator paddles, four buried underneath the HAWC position PMTs, and one freely moving paddle above the volume of water. These extra additions will allow us to work on muon reconstruction with a single WCD. We will describe the analysis being done with the data taken with the CSU prototype, its impact on the HAWC detector, and future plans for the prototype.

  11. Pocked surface neutron detector

    DOEpatents

    McGregor, Douglas; Klann, Raymond

    2003-04-08

    The detection efficiency, or sensitivity, of a neutron detector material such as of Si, SiC, amorphous Si, GaAs, or diamond is substantially increased by forming one or more cavities, or holes, in its surface. A neutron reactive material such as of elemental, or any compound of, .sup.10 B, .sup.6 Li, .sup.6 LiF, U, or Gd is deposited on the surface of the detector material so as to be disposed within the cavities therein. The portions of the neutron reactive material extending into the detector material substantially increase the probability of an energetic neutron reaction product in the form of a charged particle being directed into and detected by the neutron detector material.

  12. Simulation for Iron Calorimeter prototype detector of India-based Neutrino Observatory

    SciTech Connect

    Ghosh, Tapasi; Chattopadhyay, Subhasis

    2010-03-30

    The India-based Neutrino Observatory (INO) collaboration is proposing to build a 50 kton magnetized iron calorimeter (ICAL) detector in an underground laboratory to be located in South India. As a first step towards building the ICAL detector, a 35 ton prototype of the same design has been set up on the surface to track cosmic ray muons. This paper discusses the prototype detector geometry simulation by GEANT4, and the detector response to the cosmic muons. We have developed a track fitting procedure based on the Kalman Filter technique for the prototype detector when the detector is exposed to single muon tracks. The relevant track parameters i.e., momentum, direction and charge are reconstructed and analyzed. Finally we show the resolution of reconstructed momenta.

  13. A New Event Detector Designed for the Seismic Research Observatories

    USGS Publications Warehouse

    Murdock, James N.; Hutt, Charles R.

    1983-01-01

    A new short-period event detector has been implemented on the Seismic Research Observatories. For each signal detected, a printed output gives estimates of the time of onset of the signal, direction of the first break, quality of onset, period and maximum amplitude of the signal, and an estimate of the variability of the background noise. On the SRO system, the new algorithm runs ~2.5x faster than the former (power level) detector. This increase in speed is due to the design of the algorithm: all operations can be performed by simple shifts, additions, and comparisons (floating point operations are not required). Even though a narrow-band recursive filter is not used, the algorithm appears to detect events competitively with those algorithms that employ such filters. Tests at Albuquerque Seismological Laboratory on data supplied by Blandford suggest performance commensurate with the on-line detector of the Seismic Data Analysis Center, Alexandria, Virginia.

  14. Neutral-current detectors for the Sudbury Neutrino Observatory

    SciTech Connect

    Hime, A.; SNO Collaboration

    1997-09-01

    With its heavy water target, the Sudbury Neutrino Observatory has the unique opportunity to measure both the {sup 8}B flux of electron neutrinos from the Sun and the flux of all active neutrino species independently, thus offering a direct and model-independent test of a neutrino oscillation solution to the solar neutrino problem. The authors report on the physics intent and design of a discrete method of neutral-current detection in the Sudbury neutrino observatory that will utilize ultra-low background {sup 3}He proportional counters dispersed throughout the heavy water volume. Projections of background in all components of the detector are considered in an analysis of the ability to extract the neutral-current signal and the neutral-current to charged-current ratio.

  15. The exposure of the hybrid detector of the Pierre Auger Observatory

    SciTech Connect

    Not Available

    2010-06-01

    The Pierre Auger Observatory is a detector for ultra-high energy cosmic rays. It consists of a surface array to measure secondary particles at ground level and a fluorescence detector to measure the development of air showers in the atmosphere above the array. The 'hybrid' detection mode combines the information from the two subsystems. We describe the determination of the hybrid exposure for events observed by the fluorescence telescopes in coincidence with at least one water-Cherenkov detector of the surface array. A detailed knowledge of the time dependence of the detection operations is crucial for an accurate evaluation of the exposure. We discuss the relevance of monitoring data collected during operations, such as the status of the fluorescence detector, background light and atmospheric conditions, that are used in both simulation and reconstruction.

  16. Performance of the Pierre Auger Observatory surface array

    SciTech Connect

    Bertou, Xavier

    2005-07-01

    The surface detector of the Pierre Auger Observatory is a 1600 water Cherenkov tank array on a triangular 1.5 km grid. The signals from each tank are read out using three 9'' photomultipliers and processed at a sampling frequency of 40MHz, from which a local digital trigger efficiently selects shower candidates. GPS signals are used for time synchronization and a wireless communication system connects all tanks to the central data acquisition system. Power is provided by a stand-alone solar panel system. With large ambient temperature variations, that can reach over 20 degrees in 24 hours, high salinity, dusty air, high humidity inside the tank, and remoteness of access, the performance and reliability of the array is a challenge. Several key parameters are constantly monitored to ensure consistent operation. The Surface Array has currently over 750 detectors and has been in reliable operation since January 2004. Good uniformity in the response of different detectors and good long term stability is observed.

  17. Calibration of the surface array of the Pierre Auger Observatory

    SciTech Connect

    Aglietta, M.; Allison, P.S.; Arneodo, F.; Barnhill, D.; Bauleo, P.; Beatty, J.J.; Bertou, Xavier; Bonifazi, C.; Busca, N.; Creusot, A.; Dornic, D.; Etchegoyen, A.; Filevitch, A.; Ghia, P.L.; Grunfeld, C.M.; Lhenry-Yvon, I.; Medina, M.C.; Moreno, E.; Navarra, G.; Nitz, D.; Ohnuki, T.

    2005-08-01

    The ground array of the Pierre Auger Observatory consists of 1600 water Cherenkov detectors, deployed over 3000 km{sup 2}. The remoteness and large number of detectors required a simple, automatic remote calibration procedure. The primary physics calibration is based on the average charge deposited by a vertical and central throughgoing muon, determined with good precision at the detector via a novel rate-based technique and later with higher precision via charge histograms. This value is named the vertical-equivalent muon (VEM). The VEM and the other parameters needed to maintain this calibration over the full energy range and to assess the quality of the detector are measured every minute. This allows an accurate determination of the energy deposited in each detector when an atmospheric cosmic ray shower occurs.

  18. Background canceling surface alpha detector

    DOEpatents

    MacArthur, Duncan W.; Allander, Krag S.; Bounds, John A.

    1996-01-01

    A background canceling long range alpha detector which is capable of providing output proportional to both the alpha radiation emitted from a surface and to radioactive gas emanating from the surface. The detector operates by using an electrical field between first and second signal planes, an enclosure and the surface or substance to be monitored for alpha radiation. The first and second signal planes are maintained at the same voltage with respect to the electrically conductive enclosure, reducing leakage currents. In the presence of alpha radiation and radioactive gas decay, the signal from the first signal plane is proportional to both the surface alpha radiation and to the airborne radioactive gas, while the signal from the second signal plane is proportional only to the airborne radioactive gas. The difference between these two signals is proportional to the surface alpha radiation alone.

  19. Background canceling surface alpha detector

    DOEpatents

    MacArthur, D.W.; Allander, K.S.; Bounds, J.A.

    1996-06-11

    A background canceling long range alpha detector which is capable of providing output proportional to both the alpha radiation emitted from a surface and to radioactive gas emanating from the surface. The detector operates by using an electrical field between first and second signal planes, an enclosure and the surface or substance to be monitored for alpha radiation. The first and second signal planes are maintained at the same voltage with respect to the electrically conductive enclosure, reducing leakage currents. In the presence of alpha radiation and radioactive gas decay, the signal from the first signal plane is proportional to both the surface alpha radiation and to the airborne radioactive gas, while the signal from the second signal plane is proportional only to the airborne radioactive gas. The difference between these two signals is proportional to the surface alpha radiation alone. 5 figs.

  20. Prototype muon detectors for the AMIGA component of the Pierre Auger Observatory

    DOE PAGES

    Aab, Alexander

    2016-02-17

    AMIGA (Auger Muons and Infill for the Ground Array) is an upgrade of the Pierre Auger Observatory to extend its range of detection and to directly measure the muon content of the particle showers. It consists of an infill of surface water-Cherenkov detectors accompanied by buried scintillator detectors used for muon counting. The main objectives of the AMIGA engineering array, referred to as the Unitary Cell, are to identify and resolve all engineering issues as well as to understand the muon-number counting uncertainties related to the design of the detector. The mechanical design, fabrication and deployment processes of the muonmore » counters of the Unitary Cell are described in this document. These muon counters modules comprise sealed PVC casings containing plastic scintillation bars, wavelength-shifter optical fibers, 64 pixel photomultiplier tubes, and acquisition electronics. The modules are buried approximately 2.25 m below ground level in order to minimize contamination from electromagnetic shower particles. The mechanical setup, which allows access to the electronics for maintenance, is also described in addition to tests of the modules' response and integrity. As a result, the completed Unitary Cell has measured a number of air showers of which a first analysis of a sample event is included here.« less

  1. Prototype muon detectors for the AMIGA component of the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    The Pierre Augur Collaboration

    2016-02-01

    AMIGA (Auger Muons and Infill for the Ground Array) is an upgrade of the Pierre Auger Observatory to extend its range of detection and to directly measure the muon content of the particle showers. It consists of an infill of surface water-Cherenkov detectors accompanied by buried scintillator detectors used for muon counting. The main objectives of the AMIGA engineering array, referred to as the Unitary Cell, are to identify and resolve all engineering issues as well as to understand the muon-number counting uncertainties related to the design of the detector. The mechanical design, fabrication and deployment processes of the muon counters of the Unitary Cell are described in this document. These muon counters modules comprise sealed PVC casings containing plastic scintillation bars, wavelength-shifter optical fibers, 64 pixel photomultiplier tubes, and acquisition electronics. The modules are buried approximately 2.25 m below ground level in order to minimize contamination from electromagnetic shower particles. The mechanical setup, which allows access to the electronics for maintenance, is also described in addition to tests of the modules' response and integrity. The completed Unitary Cell has measured a number of air showers of which a first analysis of a sample event is included here.

  2. Study of the Fluorescence Detector Upgrade of the Auger Observatory of Cosmic Rays

    SciTech Connect

    Melo, D. G.; Micheletti, M. I.; Etchegoyen, A.; Rovero, A. C.

    2007-10-26

    The Pierre Auger Observatory (PAO) consists of two kinds of detectors: fluorescence detectors (FD) and surface detectors (SD). In this work we evaluate the effect, on the number and quality of the reconstructed events, of new telescopes (or 'eyes') with an enhanced field of view (FOV) up to approximately 60 degrees in elevation. By using numerical simulations, we calculated the mean total efficiency of the eye, the resolution of reconstruction of the basic parameters that characterize the primary cosmic rays (CR) and the elongation rate. To do this, we considered showers of protons and irons with energies of log(E/eV) between 17.50 and 18.25, impinging inside a circular area, placed in front of the eye at distances varying between 3.5 and 11 km. The extension of the FOV of the eye turns to be very convenient for the selected energy range, due to the fact that the atmospheric depths where the showers develop their maximum number of secondary particles (X{sub max}) are directly observed by the extended eye in most of the cases. Being this X{sub max} a parameter sensible to the chemical composition of the primary cosmic ray, its correct determination is very important in composition studies.

  3. Electronics and data acquisition system for the ICAL prototype detector of India-based neutrino observatory

    NASA Astrophysics Data System (ADS)

    Behere, A.; Bhuyan, M.; Chandratre, V. B.; Dasgupta, S.; Datar, V. M.; Kalmani, S. D.; Lahamge, S. M.; Mondal, N. K.; Mukhopadhyay, P. K.; Nagaraj, P.; Nagesh, B. K.; Pal, S.; Rao, Shobha K.; Samuel, D.; Saraf, M. N.; Satyanarayana, B.; Shastrakar, R. S.; Shinde, R. R.; Sudheer, K. M.; Upadhya, S. S.; Verma, P.

    2013-02-01

    The India-based Neutrino Observatory (INO) collaboration has proposed to build a 50 kton magnetized Iron Calorimeter (ICAL) detector with the primary goal to study neutrino oscillations, employing Resistive Plate Chambers (RPCs) as active detector elements. A prototype of the ICAL detector has been built in order to develop and characterize the intrinsic sub-systems, like RPCs, gas system, electronics and data acquisition system, etc. This paper describes in detail the readout electronics as well as the VME-based data acquisition system for the prototype detector.

  4. Search for WIMPs with NaI(Tl) detectors at Oto Cosmo Observatory

    NASA Astrophysics Data System (ADS)

    Yoshida, S.; Ejiri, H.; Fushimi, K.; Hayashi, K.; Kishimoto, T.; Kudomi, N.; Kume, K.; Kuramoto, H.; Matsuoka, K.; Ohsumi, H.; Takahisa, K.; Tsujimoto, Y.; Umehara, S.

    2003-06-01

    The cold dark matter search has been carried out at Oto Cosmo Observatory with the large volume NaI(Tl) scintillators of ELEGANT V(ELE-V). The new limits on WIMPs could be obtained by the analysis of the annual modulation. Recently, the performance of NaI(Tl) detector in ELE-V was successfully improved. these are also discussed.

  5. Surface layer characterization at Paranal Observatory

    NASA Astrophysics Data System (ADS)

    Lombardi, G.; Melnick, J.; Hinojosa Goñi, R. H.; Navarrete, J.; Sarazin, M.; Berdja, A.; Tokovinin, A.; Wilson, R.; Osborn, J.; Butterley, T.; Shepherd, H.

    2010-07-01

    In this paper the Paranal Surface Layer characterization is presented. Causes, physics and behavior of the SL above Paranal surface are discussed. The analysis is developed using data from different turbulence profilers operated during several campaigns between 2007 and 2009. Instruments used are SL-SLODAR, DIMM, Elevated DIMM, MASS, Lunar Scintillometer and Ultrasonic Anemometers with temperature sensors positioned at different strategic heights.

  6. Detector for Particle Surface Contamination

    NASA Technical Reports Server (NTRS)

    Mogan, Paul A. (Inventor); Schwindt, Christian J. (Inventor); Mattson, Carl B. (Inventor)

    1999-01-01

    A system and method for detecting and quantizing particle fallout contamination particles which are collected on a transparent disk or other surface employs an optical detector, such as a CCD camera, to obtain images of the disk and a computer for analyzing the images. From the images, the computer detects, counts and sizes particles collected on the disk The computer also determines, through comparison to previously analyzed images, the particle fallout rate, and generates an alarm or other indication if the rate exceeds a maximum allowable value. The detector and disk are disposed in a housing having an aperture formed therein for defining the area on the surface of the disk which is exposed to the particle fallout. A light source is provided for evenly illuminating the disk. A first drive motor slowly rotates the disk to increase the amount of its surface area which is exposed through the aperture to the particle fallout. A second motor is also provided for incrementally scanning the disk in a radial direction back and forth over the camera so that the camera eventually obtains images of the entire surface of the disk which is exposed to the particle fallout.

  7. VME-based data acquisition system for the India-based Neutrino Observatory prototype detector

    NASA Astrophysics Data System (ADS)

    Bhuyan, M.; Chandratre, V. B.; Dasgupta, S.; Datar, V. M.; Kalmani, S. D.; Lahamge, S. M.; Mondal, N. K.; Nagaraj, P.; Pal, S.; Rao, S. K.; Redij, A.; Samuel, D.; Saraf, M. N.; Satyanarayana, B.; Shinde, R. R.; Upadhya, S. S.

    2012-01-01

    The India-based Neutrino Observatory (INO) collaboration has proposed to build a 50 kton Iron-Calorimeter (ICAL) to study neutrino oscillations. About 28,800 Resistive Plate Chambers will be used as active detector elements in this experiment. Preliminary studies are currently underway and as a part of it, a prototype detector was developed which now serves as a cosmic-ray telescope and as a test-bench to study the indigenously built RPCs. A VME-based data acquisition system was designed for this prototype system. Modern software tools were used in the designing of the DAQ software. The design and development of this DAQ system are discussed.

  8. Searching for liquid water in Europa by using surface observatories.

    PubMed

    Khurana, Krishan K; Kivelson, Margaret G; Russell, Christopher T

    2002-01-01

    Liquid water, as far as we know, is an indispensable ingredient of life. Therefore, locating reservoirs of liquid water in extraterrestrial bodies is a necessary prerequisite to searching for life. Recent geological and geophysical observations from the Galileo spacecraft, though not unambiguous, hint at the possibility of a subsurface ocean in the Jovian moon Europa. After summarizing present evidence for liquid water in Europa, we show that electromagnetic and seismic observations made from as few as two surface observatories comprising a magnetometer and a seismometer offer the best hope of unambiguous characterization of the three-dimensional structure of the ocean and the deeper interior of this icy moon. The observatories would also help us infer the composition of the icy crust and the ocean water. PMID:12449858

  9. A Water Cherenkov Detector prototype for the HAWC Gamma-Ray Observatory

    NASA Astrophysics Data System (ADS)

    Longo, Megan; Mostafa, Miguel; Salesa Greus, Francisco; Warner, David

    2011-10-01

    A full-size Water Cherenkov Detector (WCD) prototype for the High Altitude Water Cherenkov (HAWC) gamma-ray Observatory was deployed, and is currently being operated at Colorado State University (CSU). The HAWC Observatory will consist of 300 WCDs at the very high altitude (4100m) site in Sierra Negra, Mexico. Each WCD will have 4 baffled upward-facing Photomultiplier Tubes (PMTs) anchored to the bottom of a self made multilayer hermetic plastic bag containing 200,000 liters of purified water, inside a 5m deep by 7.3m diameter steel container. The full size WCD at CSU is the only full size prototype outside of the HAWC site. It is equipped with seven HAWC PMTs and has scintillators both under and above the volume of water. It has been in operation since March 1, 2011. This prototype also has the same laser calibration system that the detectors deployed at the HAWC site will have. The CSU WCD serves as a testbed for the different subsystems before deployment at high altitude, and for optimizing the location of the PMTs, the design of the light collectors, deployment procedures, etc. Simulations of the light inside the detectors and the expected signals in the PMTs can also be benchmarked with this prototype.

  10. Development of a TES-Based Anti-Coincidence Detector for Future X-ray Observatories

    NASA Technical Reports Server (NTRS)

    Bailey, Catherine

    2011-01-01

    Microcalorimeters onboard future x-ray observatories require an anti-coincidence detector to remove environmental backgrounds. In order to most effectively integrate this anticoincidence detector with the main microcalorimeter array, both instruments should use similar read-out technology. The detectors used in the Cryogenic Dark Matter Search (CDMS) use a phonon measurement technique that is well suited for an anti-coincidence detector with a microcalorimeter array using SQUID readout. This technique works by using a transition-edge sensor (TES) connected to superconducting collection fins to measure the athermal phonon signal produced when an event occurs in the substrate crystal. Energy from the event propagates through the crystal to the superconducting collection fins, creating quasiparticles, which are then trapped as they enter the TES where they produce a signal. We are currently developing a prototype anti-coincidence detector for future x-ray missions and have recently fabricated test devices with Mo/Au TESs and Al collection fins. We will present results from the first tests of these devices which indicate a proof of concept that quasiparticle trapping is occurring in these materials.

  11. The Detector Subsystem for the SXS Instrument on the Astro-H Observatory

    NASA Technical Reports Server (NTRS)

    Porter, Frederick; Adams, J. S.; Brown, G. V.; Chervenak, J. A.; Chiao, M. P.; Fujimoto, R.; Ishisaki, Y.; Kelley, R. L.; Kilbourne, C. A.; McCammon, D.; Mitsuda, K.; Ohashi, T.; Szymkowiak, A. E.; Takei, Y.; Tashiro, M.; Yamasaki, N.

    2011-01-01

    The Soft X-ray Spectrometer (SXS) instrument on the Astro-H observatory is based on a 36 pixel x-ray calorimeter array cooled to 50 mK in a sophisticated spaceflight cryostat. The SXS is a true spatial-spectral instrument, where each spatially discrete pixel functions as a high-resolution spectrometer. Here we discuss the SXS detector subsystem that includes the detector array, the anticoincidence detector, the first stage amplifiers, the thermal and mechanical staging of the detector, and the cryogenic bias electronics. The design of the SXS detector subsystem has significant heritage from the Suzaku/XRS instrument but has some important modifications that increase performance margins and simplify the focal plane assembly. Notable improvements include x-ray absorbers with significantly lower heat capacity, improved load resistors, improved thermometry, and a decreased sensitivity to thermal radiation. These modifications have yielded an energy resolution of 3.5-4.0 eV FWHM at 6 keV for representative devices in the laboratory, giving considerable margin against the 7 eV instrument requirement. We expect similar performance in flight

  12. Apollo 17 lunar surface cosmic ray detector

    NASA Technical Reports Server (NTRS)

    Walker, R. M.

    1974-01-01

    The objectives and selected data are presented for the Apollo 17 Lunar Surface Cosmic Ray Experiment (LSCRE) for the purpose of introducing an analysis of three of the separate detectors contained within in LSCRE package. The mica detector for measuring heavy solar wind, and the lexan stack and glass detectors for measuring energetic particles in space are discussed in terms of their deployment, exposure time, calibration, and data yield. Relevant articles on solar particles, interplanetary ions, and cosmic ray nuclei are also included.

  13. Towards a gravitational wave observatory designer: sensitivity limits of spaceborne detectors

    NASA Astrophysics Data System (ADS)

    Barke, S.; Wang, Y.; Esteban Delgado, J. J.; Tröbs, M.; Heinzel, G.; Danzmann, K.

    2015-05-01

    The most promising concept for low frequency (millihertz to hertz) gravitational wave observatories are laser interferometric detectors in space. It is usually assumed that the noise floor for such a detector is dominated by optical shot noise in the signal readout. For this to be true, a careful balance of mission parameters is crucial to keep all other parasitic disturbances below shot noise. We developed a web application that uses over 30 input parameters and considers many important technical noise sources and noise suppression techniques to derive a realistic position noise budget. It optimizes free parameters automatically and generates a detailed report on all individual noise contributions. Thus one can easily explore the entire parameter space and design a realistic gravitational wave observatory. In this document we describe the different parameters, present all underlying calculations, and compare the final observatory’s sensitivity with astrophysical sources of gravitational waves. We use as an example parameters currently assumed to be likely applied to a space mission proposed to be launched in 2034 by the European Space Agency. The web application itself is publicly available on the Internet at http://spacegravity.org/designer. Future versions of the web application will incorporate the frequency dependence of different noise sources and include a more detailed model of the observatory’s residual acceleration noise.

  14. Surface purity control during XMASS detector refurbishment

    SciTech Connect

    Kobayashi, Kazuyoshi

    2015-08-17

    The XMASS project aims at detecting dark matter, pp and {sup 7}Be solar neutrinos, and neutrino less double beta decay using large volume of pure liquid xenon. The first physics target of the XMASS project is to detect dark matter with 835 kg liquid xenon. After the commissioning runs, XMASS detector was refurbished to minimize the background contribution mainly from PMT sealing material and we restarted data taking in November 2013. We report how we control surface purity, especially how we prevent radon daughter accumulation on the detector copper surface, during XMASS detector refurbishment. The result and future plan of XMASS are also reported.

  15. Measurement of the Muon Atmospheric Production Depth with the Water Cherenkov Detectors of the Pierre Auger Observatory

    SciTech Connect

    Molina Bueno, Laura

    2015-09-01

    Ultra-high-energy cosmic rays (UHECR) are particles of uncertain origin and composition, with energies above 1 EeV (1018 eV or 0.16 J). The measured flux of UHECR is a steeply decreasing function of energy. The largest and most sensitive apparatus built to date to record and study cosmic ray Extensive Air Showers (EAS) is the Pierre Auger Observatory. The Pierre Auger Observatory has produced the largest and finest amount of data ever collected for UHECR. A broad physics program is being carried out covering all relevant topics of the field. Among them, one of the most interesting is the problem related to the estimation of the mass composition of cosmic rays in this energy range. Currently the best measurements of mass are those obtained by studying the longitudinal development of the electromagnetic part of the EAS with the Fluorescence Detector. However, the collected statistics is small, specially at energies above several tens of EeV. Although less precise, the volume of data gathered with the Surface Detector is nearly a factor ten larger than the fluorescence data. So new ways to study composition with data collected at the ground are under investigation. The subject of this thesis follows one of those new lines of research. Using preferentially the time information associated with the muons that reach the ground, we try to build observables related to the composition of the primaries that initiated the EAS. A simple phenomenological model relates the arrival times with the depths in the atmosphere where muons are produced. The experimental confirmation that the distributions of muon production depths (MPD) correlate with the mass of the primary particle has opened the way to a variety of studies, of which this thesis is a continuation, with the aim of enlarging and improving its range of applicability. We revisit the phenomenological model which is at the root of the analysis and discuss a new way to improve some aspects of the model. We carry

  16. The detector response matrices of the burst and transient source experiment (BATSE) on the Compton Gamma Ray Observatory

    NASA Technical Reports Server (NTRS)

    Pendleton, Geoffrey N.; Paciesas, William S.; Mallozzi, Robert S.; Koshut, Tom M.; Fishman, Gerald J.; Meegan, Charles A.; Wilson, Robert B.; Horack, John M.; Lestrade, John Patrick

    1995-01-01

    The detector response matrices for the Burst And Transient Source Experiment (BATSE) on board the Compton Gamma Ray Observatory (CGRO) are described, including their creation and operation in data analysis. These response matrices are a detailed abstract representation of the gamma-ray detectors' operating characteristics that are needed for data analysis. They are constructed from an extensive set of calibration data coupled with a complex geometry electromagnetic cascade Monte Carlo simulation code. The calibration tests and simulation algorithm optimization are described. The characteristics of the BATSE detectors in the spacecraft environment are also described.

  17. Surface wave chemical detector using optical radiation

    DOEpatents

    Thundat, Thomas G.; Warmack, Robert J.

    2007-07-17

    A surface wave chemical detector comprising at least one surface wave substrate, each of said substrates having a surface wave and at least one measurable surface wave parameter; means for exposing said surface wave substrate to an unknown sample of at least one chemical to be analyzed, said substrate adsorbing said at least one chemical to be sensed if present in said sample; a source of radiation for radiating said surface wave substrate with different wavelengths of said radiation, said surface wave parameter being changed by said adsorbing; and means for recording signals representative of said surface wave parameter of each of said surface wave substrates responsive to said radiation of said different wavelengths, measurable changes of said parameter due to adsorbing said chemical defining a unique signature of a detected chemical.

  18. Observed On-Orbit Background of the ACIS Detector on the Chandra X-Ray Observatory

    NASA Technical Reports Server (NTRS)

    Plucinsky, P. P.; Virani, S. N.

    2000-01-01

    We have analyzed calibration data acquired during the Orbital Activation and Checkout (OAC) phase of the Chandra X-ray Observatory (CXO) mission in order to characterize the background of the Advanced CCD Imaging Spectrometer (ACIS) produced by charged particles and non-cosmic X-rays. The ACIS instrument contains 8 Front-Illuminated (FI) CCDs and 2 Back-Illuminated (BI) CCDs. The FI and BI CCD)s exhibit dramatically different responses to enhancements in the particle flux. The F1 CCDs show relatively little increase in the overall count rate, typical increases are 1 - 3 counts/s; the BI CCDs show large excursions to as high as 100 counts/s. The duration of these intervals of enhanced background are highly variable ranging from 100 s to 5000 s. The spatial distribution of these background events is relatively flat across the power-law. The events produce morphologies which are similar to cosmic X-ray events, so that morphology alone cannot be used as a rejection criterion. We explore the correlation of these times of high background with the data from Chandra's on-board radiation monitor, the EPHIN (Electron, Proton, Helium Instrument particle detector) instrument and archival data from the Advanced Composition Explorer (ACE) satellite. We discuss strategies for observers to identify and exclude times of high background and to model and subtract the background events from their data.

  19. Acceptance and Angular Resolution of an Infill Array for the Pierre Auger Surface Detector

    SciTech Connect

    Medina, C.; Gomez Berisso, M.; Allekotte, I.; Etchegoyen, A.; Supanitsky, D.; Medina-Tanco, G.

    2007-02-12

    The Pierre Auger Observatory has been designed to study the highest-energy cosmic rays in nature (E {>=} 1019 eV). The determination of their arrival direction, energy and composition is performed by the analysis of the atmospheric showers they produce. The Auger Surface Array will consist of 1600 water Cerenkov detectors placed in an equilateral triangular grid of 1.5 km. In this paper we show how adding a ''small'' area of surface detectors at half the above mentioned spacing would make it possible to lower the detection threshold by one order of magnitude, thus allowing the Observatory to reach lower energies where the cross-over from galactic to extragalactic sources is expected. We also analyze the angular resolution that can be attained with such an infill array.

  20. Microtextured Silicon Surfaces for Detectors, Sensors & Photovoltaics

    SciTech Connect

    Carey, JE; Mazur, E

    2005-05-19

    With support from this award we studied a novel silicon microtexturing process and its application in silicon-based infrared photodetectors. By irradiating the surface of a silicon wafer with intense femtosecond laser pulses in the presence of certain gases or liquids, the originally shiny, flat surface is transformed into a dark array of microstructures. The resulting microtextured surface has near-unity absorption from near-ultraviolet to infrared wavelengths well below the band gap. The high, broad absorption of microtextured silicon could enable the production of silicon-based photodiodes for use as inexpensive, room-temperature multi-spectral photodetectors. Such detectors would find use in numerous applications including environmental sensors, solar energy, and infrared imaging. The goals of this study were to learn about microtextured surfaces and then develop and test prototype silicon detectors for the visible and infrared. We were extremely successful in achieving our goals. During the first two years of this award, we learned a great deal about how microtextured surfaces form and what leads to their remarkable optical properties. We used this knowledge to build prototype detectors with high sensitivity in both the visible and in the near-infrared. We obtained room-temperature responsivities as high as 100 A/W at 1064 nm, two orders of magnitude higher than standard silicon photodiodes. For wavelengths below the band gap, we obtained responsivities as high as 50 mA/W at 1330 nm and 35 mA/W at 1550 nm, close to the responsivity of InGaAs photodiodes and five orders of magnitude higher than silicon devices in this wavelength region.

  1. Studies of the Sudbury Neutrino Observatory detector and sonoluminescence using a sonoluminescent source

    NASA Astrophysics Data System (ADS)

    McDonald, Douglas Steven

    The Sudbury Neutrino Observatory (SNO) is the first heavy water Cerenkov solar neutrino detector. 1000 metric tonnes of heavy water is used as a neutrino target and detection medium. SNO is designed to measure the flux and energy spectrum of high energy solar electron neutrinos via charged current interactions of electron neutrinos with deuterons in the heavy water. SNO can also measure the total high energy solar neutrino flux of neutrinos of all flavors via neutral current interactions with deuterons. The physics of solar models and solar neutrinos is presented. The physics of SNO and the SNO detector are described in detail. Two sonoluminescence sources were developed for use in calibrations of the SNO detector. The sonoluminescence source outperformed the standard SNO optical source, a nitrogen laser with a diffuser ball, by 25% in measurements of photomultiplier tube timing accuracy. Two systematic effects with the SNO electronics were discovered. Electronic crosstalk between channels has been measured for charges greater than 5 photoelectrons. An efficient cut has been developed to minimize this systematic error with an upper limit on signal loss of 0.4% times the PMT occupancy. Electronics crosstalk will affect solar neutrino analyses as it falsely adds PMT hits to some fraction of the events. A small anticorrelation of photomultiplier charges for electronics channels in close proximity has been measured. It has been shown that this subtle effect does not affect the number of photons detected, only the photomultiplier charges. A SL source and the SNO detector were used to study three properties of sonoluminescence. An analysis of SL data with regard to back-to-back photon correlations is presented. The results are consistent with no back-to- back photon correlations with an upper limit on the strength of back-to-back photon correlations of 3.16% for unfiltered SL light, and 0.5% for filtered SL light (λ = 420 nm) at the 95% confidence level. The SL photon

  2. The Radio Observatory on the Lunar Surface for Solar studies

    NASA Astrophysics Data System (ADS)

    Lazio, T. Joseph W.; MacDowall, R. J.; Burns, Jack O.; Jones, D. L.; Weiler, K. W.; Demaio, L.; Cohen, A.; Paravastu Dalal, N.; Polisensky, E.; Stewart, K.; Bale, S.; Gopalswamy, N.; Kaiser, M.; Kasper, J.

    2011-12-01

    The Radio Observatory on the Lunar Surface for Solar studies (ROLSS) is a concept for a near-side low radio frequency imaging interferometric array designed to study particle acceleration at the Sun and in the inner heliosphere. The prime science mission is to image the radio emission generated by Type II and III solar radio burst processes with the aim of determining the sites at and mechanisms by which the radiating particles are accelerated. Specific questions to be addressed include the following: (1) Isolating the sites of electron acceleration responsible for Type II and III solar radio bursts during coronal mass ejections (CMEs); and (2) Determining if and the mechanism(s) by which multiple, successive CMEs produce unusually efficient particle acceleration and intense radio emission. Secondary science goals include constraining the density of the lunar ionosphere by searching for a low radio frequency cutoff to solar radio emission and constraining the low energy electron population in astrophysical sources. Key design requirements on ROLSS include the operational frequency and angular resolution. The electron densities in the solar corona and inner heliosphere are such that the relevant emission occurs at frequencies below 10 MHz. Second, resolving the potential sites of particle acceleration requires an instrument with an angular resolution of at least 2°, equivalent to a linear array size of approximately 1000 m. Operations would consist of data acquisition during the lunar day, with regular data downlinks. No operations would occur during lunar night. ROLSS is envisioned as an interferometric array, because a single aperture would be impractically large. The major components of the ROLSS array are 3 antenna arms arranged in a Y shape, with a central electronics package (CEP) located at the center. The Y configuration for the antenna arms both allows for the formation of reasonably high dynamic range images on short time scales as well as relatively easy

  3. Operations of and Future Plans for the Pierre Auger Observatory

    SciTech Connect

    Abraham, : J.; Abreu, P.; Aglietta, M.; Aguirre, C.; Ahn, E.J.; Allard, D.; Allekotte, I.; Allen, J.; Alvarez-Muniz, J.; Ambrosio, M.; Anchordoqui, L.

    2009-06-01

    These are presentations to be presented at the 31st International Cosmic Ray Conference, in Lodz, Poland during July 2009. It consists of the following presentations: (1) Performance and operation of the Surface Detectors of the Pierre Auger Observatory; (2) Extension of the Pierre Auger Observatory using high-elevation fluorescence telescopes (HEAT); (3) AMIGA - Auger Muons and Infill for the Ground Array of the Pierre Auger Observatory; (4) Radio detection of Cosmic Rays at the southern Auger Observatory; (5) Hardware Developments for the AMIGA enhancement at the Pierre Auger Observatory; (6) A simulation of the fluorescence detectors of the Pierre Auger Observatory using GEANT 4; (7) Education and Public Outreach at the Pierre Auger Observatory; (8) BATATA: A device to characterize the punch-through observed in underground muon detectors and to operate as a prototype for AMIGA; and (9) Progress with the Northern Part of the Pierre Auger Observatory.

  4. Greenland Neutrino Observatory (GNO): A New Detector for Ultra-high Energy Neutrinos

    NASA Astrophysics Data System (ADS)

    Vieregg, Abigail

    2014-03-01

    Neutrinos travel virtually unimpeded through the universe, making them unique messenger particles for cosmic sources and carrying information about very distant sources that would otherwise be unavailable. The observation of ultra-high energy (UHE) neutrinos (E >1018 eV) would also allow a measurement of weak interaction couplings at center of mass energies well beyond that of the LHC and reveal the origin of the highest energy cosmic rays. We are planning to deploy a new array of radio detectors for UHE neutrinos near the surface of the ice at Summit Station in Greenland, a year-round NSF station that sits atop 3 km of ice at the height of the Greenland plateau. The full array will have the sensitivity required to discover neutrinos produced through the so-called GZK process (the interaction of the highest energy cosmic rays with cosmic microwave background photons) even in the most pessimistic of models and will detect ~ 10 events per year at the high-energy portion (E >1015 eV) of the observed IceCube astrophysical neutrino spectrum with sub-degree pointing resolution. We are planning to deploy our first module in the summer of 2014.

  5. Electron-beam studies of Schottky-barrier detector surfaces

    NASA Technical Reports Server (NTRS)

    Peckerar, M. C.

    1973-01-01

    Review of the surface anomalies occurring in Schottky-barrier particle detectors identifiable by means of an electron beam technique employed by Czaja (1965) for analyzing defects in diode structures. The technique is shown to make possible the detection and identification of the following anomalies: (1) chemical contamination of the detector surface; (2) mechanical damage of the wafer substrates; (3) damage introduced in semiconductor surface preparation; (4) radiation damage; and (5) defective surface metallization.

  6. Charged particle detectors with active detector surface for partial energy deposition of the charged particles and related methods

    DOEpatents

    Gerts, David W; Bean, Robert S; Metcalf, Richard R

    2013-02-19

    A radiation detector is disclosed. The radiation detector comprises an active detector surface configured to generate charge carriers in response to charged particles associated with incident radiation. The active detector surface is further configured with a sufficient thickness for a partial energy deposition of the charged particles to occur and permit the charged particles to pass through the active detector surface. The radiation detector further comprises a plurality of voltage leads coupled to the active detector surface. The plurality of voltage leads is configured to couple to a voltage source to generate a voltage drop across the active detector surface and to separate the charge carriers into a plurality of electrons and holes for detection. The active detector surface may comprise one or more graphene layers. Timing data between active detector surfaces may be used to determine energy of the incident radiation. Other apparatuses and methods are disclosed herein.

  7. Silicon surface barrier detectors used for liquid hydrogen density measurement

    NASA Technical Reports Server (NTRS)

    James, D. T.; Milam, J. K.; Winslett, H. B.

    1968-01-01

    Multichannel system employing a radioisotope radiation source, strontium-90, radiation detector, and a silicon surface barrier detector, measures the local density of liquid hydrogen at various levels in a storage tank. The instrument contains electronic equipment for collecting the density information, and a data handling system for processing this information.

  8. Focal-surface detector for heavy ions

    DOEpatents

    Erskine, John R.; Braid, Thomas H.; Stoltzfus, Joseph C.

    1979-01-01

    A detector of the properties of individual charged particles in a beam includes a gridded ionization chamber, a cathode, a plurality of resistive-wire proportional counters, a plurality of anode sections, and means for controlling the composition and pressure of gas in the chamber. Signals generated in response to the passage of charged particles can be processed to identify the energy of the particles, their loss of energy per unit distance in an absorber, and their angle of incidence. In conjunction with a magnetic spectrograph, the signals can be used to identify particles and their state of charge. The detector is especially useful for analyzing beams of heavy ions, defined as ions of atomic mass greater than 10 atomic mass units.

  9. Description and preliminary test results of a detector prototype for the TUS space fluorescence observatory

    NASA Astrophysics Data System (ADS)

    Cordero, A.; Garipov, G.; Khrenov, B.; Martinez, O.; Murrieta, T.; Robledo, C.; Rodriguez, L.; Salazar, H.; Villasenor, L.

    We discuss a general scheme of the optics and electronics read out as well as preliminary test results of a detector prototype for the space fluorescence telescope TUS (FD-TUS). The mirror of this prototype is coupled to an 8 by 8 pixel camera. Each of the 64 pixels is read by one PMT of 13 mm diameter (Hamamatsu model R1463) . The optics design is a multi-hexagonal segmented telescope with focal distance of 1.5m and 2 square meter area. The optics design is optimized to have a light collection efficiency greater then 50% for all the pixel positions. The fluorescence detector is being tested at the high mountain site Sierra La Negra near Puebla City in Mexico (600g/cm2). The FD-TUS will observe EAS tracks at energies of about 1 EeV at distances 25-50km,and zenith angles greater than 45 degree with direction tracks perpendicular to the FD axis.

  10. Surface Leakage Mechanisms in III-V Infrared Barrier Detectors

    NASA Astrophysics Data System (ADS)

    Sidor, D. E.; Savich, G. R.; Wicks, G. W.

    2016-09-01

    Infrared detector epitaxial structures employing unipolar barriers exhibit greatly reduced dark currents compared to simple pn-based structures. When correctly positioned within the structure, unipolar barriers are highly effective at blocking bulk dark current mechanisms. Unipolar barriers are also effective at suppressing surface leakage current in infrared detector structures employing absorbing layers that possess the same conductivity type in their bulk and at their surface. When an absorbing layer possesses opposite conductivity types in its bulk and at its surface, unipolar barriers are not solutions to surface leakage. This work reviews empirically determined surface band alignments of III-V semiconductor compounds and modeled surface band alignments of both gallium-free and gallium-containing type-II strained layer superlattice material systems. Surface band alignments are used to predict surface conductivity types in several detector structures, and the relationship between surface and bulk conductivity types in the absorbing layers of these structures is used as the basis for explaining observed surface leakage characteristics.

  11. SWIR hyperspectral imaging detector for surface residues

    NASA Astrophysics Data System (ADS)

    Nelson, Matthew P.; Mangold, Paul; Gomer, Nathaniel; Klueva, Oksana; Treado, Patrick

    2013-05-01

    ChemImage has developed a SWIR Hyperspectral Imaging (HSI) sensor which uses hyperspectral imaging for wide area surveillance and standoff detection of surface residues. Existing detection technologies often require close proximity for sensing or detecting, endangering operators and costly equipment. Furthermore, most of the existing sensors do not support autonomous, real-time, mobile platform based detection of threats. The SWIR HSI sensor provides real-time standoff detection of surface residues. The SWIR HSI sensor provides wide area surveillance and HSI capability enabled by liquid crystal tunable filter technology. Easy-to-use detection software with a simple, intuitive user interface produces automated alarms and real-time display of threat and type. The system has potential to be used for the detection of variety of threats including chemicals and illicit drug substances and allows for easy updates in the field for detection of new hazardous materials. SWIR HSI technology could be used by law enforcement for standoff screening of suspicious locations and vehicles in pursuit of illegal labs or combat engineers to support route-clearance applications- ultimately to save the lives of soldiers and civilians. In this paper, results from a SWIR HSI sensor, which include detection of various materials in bulk form, as well as residue amounts on vehicles, people and other surfaces, will be discussed.

  12. Geothermal climate change observatory in south India 1: Borehole temperatures and inferred surface temperature histories

    NASA Astrophysics Data System (ADS)

    Akkiraju, Vyasulu V.; Roy, Sukanta

    Temperature-depth profiles measured in boreholes contain records of changes in surface ground temperature over the past few centuries. We have recently set up a geothermal climate change observatory at the Choutuppal campus of National Geophysical Research Institute (17.29 °N, 78.92 °E) to measure subsurface temperature changes on annual to decadal timescales and quantify how well they track surface temperature changes. The site is located about 60 km to the east of Hyderabad in south India, in a designated reserved forest land and far from potential urban heat islands. In April 2009, two boreholes were drilled to depths of 210 m and 21 m respectively after careful site selection to minimize perturbations to the subsurface temperatures on account of groundwater flow in the borehole, large thermal conductivity contrasts and rugged topography. Temperature measurements in the two holes are being carried out periodically. Analysis of equilibrium temperature-depth profile in the 210 m deep borehole reveals at least two ongoing events that started during the past Century: (i) surface ground warming of 0.5 ± 0.1 °C over the past 92 ± 7 years, and (ii) a more recent cooling of ∼1 °C over the past ∼39 years, probably representing local changes to surface vegetation caused by the presence of a thicker grass cover throughout the year inside the campus since 1967 AD compared to the short cropping of grass outside it. The inferred surface ground warming is consistent with estimates from temperature measurements in three other boreholes (170-300 m deep) distributed in a 10 × 5 km 2 area in the vicinity of the observatory (mean: 0.5 ± 0.1 °C over the past 93 ± 21 years), and is characteristic of the Interior Peninsula region of south India.

  13. Effects of surface reflectance on skylight polarization measurements at the Mauna Loa Observatory

    NASA Astrophysics Data System (ADS)

    Dahlberg, Andrew R.; Pust, Nathan J.; Shaw, Joseph A.

    2011-08-01

    An all-sky imaging polarimeter was deployed in summer 2008 to the Mauna Loa Observatory in Hawaii to study clear-sky atmospheric skylight polarization. The imager operates in five wavebands in the visible and near infrared spectrum and has a fisheye lens for all-sky viewing. This paper describes the deployment and presents comparisons of the degree of skylight polarization observed to similar data observed by Coulson with a principal-plane scanning polarimeter in the late 1970s. In general, the results compared favorably to those of Coulson. In addition, we present quantitative results correlating a variation of the maximum degree of polarization over a range of 70-85% to fluctuation in underlying surface reflectance and upwelling radiance data from the GOES satellite.

  14. Effects of surface reflectance on skylight polarization measurements at the Mauna Loa Observatory.

    PubMed

    Dahlberg, Andrew R; Pust, Nathan J; Shaw, Joseph A

    2011-08-15

    An all-sky imaging polarimeter was deployed in summer 2008 to the Mauna Loa Observatory in Hawaii to study clear-sky atmospheric skylight polarization. The imager operates in five wavebands in the visible and near infrared spectrum and has a fisheye lens for all-sky viewing. This paper describes the deployment and presents comparisons of the degree of skylight polarization observed to similar data observed by Coulson with a principal-plane scanning polarimeter in the late 1970s. In general, the results compared favorably to those of Coulson. In addition, we present quantitative results correlating a variation of the maximum degree of polarization over a range of 70-85% to fluctuation in underlying surface reflectance and upwelling radiance data from the GOES satellite. PMID:21934965

  15. Measuring wintertime surface fluxes at the Tiksi observatory in northern Sakha (Yakutia)

    NASA Astrophysics Data System (ADS)

    Laurila, Thomas; Aurela, Mika; Hatakka, Juha; Tuovinen, Juha-Pekka; Asmi, Eija; Kondratyev, Vladimir; Ivakhov, Victor; Reshetnikov, Alexander; Makshtas, Alexander; Uttal, Taneil

    2013-04-01

    Tiksi hydrometeorological observatory has been equipped by new instrumentation for meteorology, turbulence, trace gas and aerosols studies as a joint effort by National Oceanic and Atmospheric Administration (NOAA), Roshydromet (Yakutian Hydrometeorological Service, Arctic and Antarctic Research Institute and Voeikov Main Geophysical Observatory units) and the Finnish Meteorological Institute (FMI). The site is close to the coast of the Laptev Sea on deep permafrost soil with low tundra vegetation and patches of arctic semidesert. Near-by terrain is gently sloping to the south. Further away they are hills in the NE- and W-directions. Turbulence (3-d wind components and sonic temperature) was measured at 10 Hz by USA-1Scientific sonic by Metek, Gmbh. Concentrations of CO2 and H2O were measured by LiCor LI7000 analyzer and CH4 concentrations by Los Gatos RMT200 analyzer. Measurement height was 2.5m. Active layer freeze up took place in extended October period. Methane and carbon dioxide emissions were observed up to early December. Emissions to the atmosphere were enhanced by turbulence created by high wind speeds. Midwinter conditions existed from the end of October to the beginning of April based on rather constant negative net radiation between 20-30 Wm-2 that cools the surface and forms highly stable stratification. Weather conditions are characterized by either low or high wind speed modes. Roughly half of the time wind speed was low, below 2 ms-1. Then, katabatic winds were common and air temperature was between -40..-30°C. High wind speeds, up to 24 ms-1, were observed during synoptic disturbances which lasted typically a few days. In this presentation we will show climatology of surface layer characteristics in late autumn and winter. We will show frequency of well-developed turbulence vs. katabatic low wind speed conditions and related atmospheric stability. The effect of wind speed on methane and carbon dioxide emissions during the freezing period will be

  16. Intial performance from the NOvA surface prototype detector

    SciTech Connect

    Muether, M.; /Fermilab

    2011-09-01

    NOvA, the NuMI Off-Axis {nu}{sub e} Appearance experiment, will study {nu}{sub {mu}} {yields} {nu}{sub e} oscillations characterized by the mixing angle {Theta}{sub 13}. Provided {Theta}{sub 13} is large enough, NOvA may ultimately determine the ordering of the neutrino masses and measure CP violation in neutrino oscillations. A complementary pair of detectors will be constructed {approx}14 mrad off beam axis to optimize the energy profile of the neutrinos. This system consists of a surface based 14 kTon liquid scintillator tracking volume located 810 km from the main injector source (NuMI) in Ash River, Minnesota and a smaller underground 222 Ton near detector at the Fermilab. The first neutrino signals at the Ash River Site are expected prior to the 2012 accelerator shutdown. In the meantime, a near detector surface prototype has been completed and neutrinos from two Fermilab sources have been observed using the same highly segmented PVC and liquid scintillator detector system that will be deployed in the full scale experiment. Design and initial performance characteristics of this prototype system are being fed back into the design for the full NOvA program.

  17. Studies of Cosmic Ray Composition and Air Shower Structure with the Pierre Auger Observatory

    SciTech Connect

    Abraham, : J.; Abreu, P.; Aglietta, M.; Aguirre, C.; Ahn, E.J.; Allard, D.; Allekotte, I.; Allen, J.; Alvarez-Muniz, J.; Ambrosio, M.; Anchordoqui, L.

    2009-06-01

    These are presentations to be presented at the 31st International Cosmic Ray Conference, in Lodz, Poland during July 2009. It consists of the following presentations: (1) Measurement of the average depth of shower maximum and its fluctuations with the Pierre Auger Observatory; (2) Study of the nuclear mass composition of UHECR with the surface detectors of the Pierre Auger Observatory; (3) Comparison of data from the Pierre Auger Observatory with predictions from air shower simulations: testing models of hadronic interactions; (4) A Monte Carlo exploration of methods to determine the UHECR composition with the Pierre Auger Observatory; (5) The delay of the start-time measured with the Pierre Auger Observatory for inclined showers and a comparison of its variance with models; (6) UHE neutrino signatures in the surface detector of the Pierre Auger Observatory; and (7) The electromagnetic component of inclined air showers at the Pierre Auger Observatory.

  18. Study of the surface ionization detector for gas chromatography.

    PubMed

    Li, Weiwei; Wu, Dapeng; Chen, Shiheng; Peng, Hong; Guan, Yafeng

    2011-09-23

    The structure of the surface ionization detector (SID) and the operation parameters of GC-SID were investigated to reduce peak tailing and to enhance sensitivity. The performances of the GC-SID, including its repeatability, linearity, sensitivity, selectivity, and tolerance towards water vapor, were evaluated systematically. Compared with nitrogen-phosphorus detector (NPD), the SID was able to detect fg level triethylamine, and selectively respond to alkylamines, some anilines, and some nitrogen heterocyclic compounds. Among alkylamines, the SID sensitivity to diisobutylamine was rather small. Even so, it was also still 10 times higher than that on NPD. The SID selectivity, defined as the sensitivity ratio between triethylamine and various tested non-nitrogen compounds, was higher than 10(6). It was found that the SID is highly tolerant towards water vapor, allowing direct injection of water sample. Finally, the GC-SID was applied to directly measure trace amines in headspace gases of rotted meat and trace simazine in tap water. The SID sensitivity to simazine was proven to be 5 times higher than that on flame ionization detector (FID). This study suggests that the SID is a promising GC detector. PMID:21839459

  19. The Cosmic Ray Energy Spectrum and Related Measurements with the Pierre Auger Observatory

    SciTech Connect

    Abraham, : J.; Abreu, P.; Aglietta, M.; Aguirre, C.; Ahn, E.J.; Allard, D.; Allekotte, I.; Allen, J.; Alvarez-Muniz, J.; Ambrosio, M.; Anchordoqui, L.

    2009-06-01

    These are presentations to be presented at the 31st International Cosmic Ray Conference, in Lodz, Poland during July 2009. It consists of the following presentations: (1) Measurement of the cosmic ray energy spectrum above 10{sup 18} eV with the Pierre Auger Observatory; (2) The cosmic ray flux observed at zenith angles larger than 60 degrees with the Pierre Auger Observatory; (3) Energy calibration of data recorded with the surface detectors of the Pierre Auger Observatory; (4) Exposure of the Hybrid Detector of The Pierre Auger Observatory; and (5) Energy scale derived from Fluorescence Telescopes using Cherenkov Light and Shower Universality.

  20. Solar Cycle and Anthropogenic Forcing of Surface-Air Temperature at Armagh Observatory, Northern Ireland

    NASA Technical Reports Server (NTRS)

    Wilson, Robert M.

    2010-01-01

    A comparison of 10-yr moving average (yma) values of Armagh Observatory (Northern Ireland) surface-air temperatures with selected solar cycle indices (sunspot number (SSN) and the Aa geomagnetic index (Aa)), sea-surface temperatures in the Nino 3.4 region, and Mauna Loa carbon dioxide (CO2) (MLCO2) atmospheric concentration measurements reveals a strong correlation (r = 0.686) between the Armagh temperatures and Aa, especially, prior to about 1980 (r = 0.762 over the interval of 1873-1980). For the more recent interval 1963-2003, the strongest correlation (r = 0.877) is between Armagh temperatures and MLCO2 measurements. A bivariate fit using both Aa and Mauna Loa values results in a very strong fit (r = 0.948) for the interval 1963-2003, and a trivariate fit using Aa, SSN, and Mauna Loa values results in a slightly stronger fit (r = 0.952). Atmospheric CO2 concentration now appears to be the stronger driver of Armagh surface-air temperatures. An increase of 2 C above the long-term mean (9.2 C) at Armagh seems inevitable unless unabated increases in anthropogenic atmospheric gases can be curtailed. The present growth in 10-yma Armagh temperatures is about 0.05 C per yr since 1982. The present growth in MLCO2 is about 0.002 ppmv, based on an exponential fit using 10-yma values, although the growth appears to be steepening, thus, increasing the likelihood of deleterious effects attributed to global warming.

  1. Decadal variability in core surface flows deduced from geomagnetic observatory monthly means

    NASA Astrophysics Data System (ADS)

    Whaler, K. A.; Olsen, N.; Finlay, C. C.

    2016-10-01

    Monthly means of the magnetic field measurements at ground observatories are a key data source for studying temporal changes of the core magnetic field. However, when they are calculated in the usual way, contributions of external (magnetospheric and ionospheric) origin may remain, which make them less favourable for studying the field generated by dynamo action in the core. We remove external field predictions, including a new way of characterizing the magnetospheric ring current, from the data and then calculate revised monthly means using robust methods. The geomagnetic secular variation (SV) is calculated as the first annual differences of these monthly means, which also removes the static crustal field. SV time-series based on revised monthly means are much less scattered than those calculated from ordinary monthly means, and their variances and correlations between components are smaller. On the annual to decadal timescale, the SV is generated primarily by advection in the fluid outer core. We demonstrate the utility of the revised monthly means by calculating models of the core surface advective flow between 1997 and 2013 directly from the SV data. One set of models assumes flow that is constant over three months; such models exhibit large and rapid temporal variations. For models of this type, less complex flows achieve the same fit to the SV derived from revised monthly means than those from ordinary monthly means. However, those obtained from ordinary monthly means are able to follow excursions in SV that are likely to be external field contamination rather than core signals. Having established that we can find models that fit the data adequately, we then assess how much temporal variability is required. Previous studies have suggested that the flow is consistent with torsional oscillations (TO), solid body-like oscillations of fluid on concentric cylinders with axes aligned along the Earth's rotation axis. TO have been proposed to explain decadal

  2. Decadal variability in core surface flows deduced from geomagnetic observatory monthly means

    NASA Astrophysics Data System (ADS)

    Whaler, K. A.; Olsen, N.; Finlay, C. C.

    2016-07-01

    Monthly means of the magnetic field measurements at ground observatories are a key data source for studying temporal changes of the core magnetic field. However, when they are calculated in the usual way, contributions of external (magnetospheric and ionospheric) origin may remain, which make them less favourable for studying the field generated by dynamo action in the core. We remove external field predictions, including a new way of characterising the magnetospheric ring current, from the data and then calculate revised monthly means using robust methods. The geomagnetic secular variation (SV) is calculated as the first annual differences of these monthly means, which also removes the static crustal field. SV time series based on revised monthly means are much less scattered than those calculated from ordinary monthly means, and their variances and correlations between components are smaller. On the annual to decadal timescale, the SV is generated primarily by advection in the fluid outer core. We demonstrate the utility of the revised monthly means by calculating models of the core surface advective flow between 1997 and 2013 directly from the SV data. One set of models assumes flow that is constant over three months; such models exhibit large and rapid temporal variations. For models of this type, less complex flows achieve the same fit to the SV derived from revised monthly means than those from ordinary monthly means. However, those obtained from ordinary monthly means are able to follow excursions in SV that are likely to be external field contamination rather than core signals. Having established that we can find models that fit the data adequately, we then assess how much temporal variability is required. Previous studies have suggested that the flow is consistent with torsional oscillations (TO), solid body-like oscillations of fluid on concentric cylinders with axes aligned along the Earth's rotation axis. TO have been proposed to explain decadal

  3. The Planet Mercury Surface Spectroscopy and Analysis from the Kuiper Airborne Observatory and Analysis and Modeling to Determine Surface Composition

    NASA Technical Reports Server (NTRS)

    Sprague, Ann

    1997-01-01

    We had two successful flights to observe Mercury from the Kuiper Airborne Observatory (KAO) using High-efficiency Infrared Faint-Object Grating Spectrograph (HIFOGS). Flights were May 8, 1995 (eastern elongation) and July 6, 1995 (western elongation) For the observations one half of the primary mirror was covered to prevent sunlight from entering the telescope. All equipment and the airplane and its crew performed well. These flights were historical firsts for the KAO and for spectroscopy of Mercury in that it was the first time any spectroscopic observations of Mercury from above the Earth's atmosphere had been made. It was the first time the KAO had been used to @bserve an object less than 30 degrees from the Sun. Upon completion of the basic data reduction it became obvious that extensive modeling and analysis would be required to understand the data. It took three years of a graduate student's time and part time the PI to do the thermal modeling and the spectroscopic analysis. This resulted in a lengthy publication. A copy of this publication is attached and has all the data obtained in both KAO flights and the results clearly presented. Notable results are: (1) The observations found an as yet unexplained 5 micron emission enhancement that we think may be a real characteristic of Mercury's surface but could have an instrumental cause; (2) Ground-based measurements or an emission maximum at 7.7 microns were corroborated. The chemical composition of Mercury's surface must be feldspathic in order to explain spectra features found in the data obtained during the KAO flights.

  4. AMIGA at the Auger observatory: the telecommunications system

    NASA Astrophysics Data System (ADS)

    Platino, M.; Hampel, M. R.; Fiszelew, P.; Almela, A.; Sedoski, A.; De La Vega, G.; Videla, M.; Lucero, A.; Suarez, F.; Wainberg, O.; Yelos, D.; Cancio, A.; Garcia, B.; Etchegoyen, A.

    2013-12-01

    AMIGA is an extension of the Pierre Auger Observatory that will consist of 85 detector pairs, each one composed of a surface water-Cherenkov detector and a buried muon counter. Each muon counter has an area of 30 square meters and is made of scintillator strips, with doped optical fibers glued to them, which guide the light to 64 pixel photomultiplier tubes. The detector pairs are arranged at 433 m and 750 m array spacings. In this paper we present the telecommunications system designed to connect the muon counters with the central data processing system at the observatory campus in Malarg"ue. The telecommunications system consists of a point-to-multipoint radio link designed to connect the 85 muon counters or subscribers to two coordinators located at the Coihueco fluorescence detector building. The link provides TCP/IP remote access to the scintillator modules through router boards installed on each of the surface detectors of AMIGA. This setup provides a flexible LAN configuration for each muon counter connected to a WAN that links all the data generated by the muon counters and the surface detectors to the Central Data Acquisition System, or CDAS, at the observatory campus. We present the design parameters, the proposed telecommunications solution and the laboratory and field tests proposed to guarantee its functioning for the whole data traffic generated between each surface detector and muon counter in the AMIGA array and the CDAS.

  5. Development of the superconducting detectors and read-out for the X-IFU instrument on board of the X-ray observatory Athena

    NASA Astrophysics Data System (ADS)

    Gottardi, L.; Akamatsu, H.; Bruijn, M. P.; den Hartog, R.; den Herder, J.-W.; Jackson, B.; Kiviranta, M.; van der Kuur, J.; van Weers, H.

    2016-07-01

    The Advanced Telescope for High-Energy Astrophysics (Athena) has been selected by ESA as its second large-class mission. The future European X-ray observatory will study the hot and energetic Universe with its launch foreseen in 2028. Microcalorimeters based on superconducting Transition-edge sensor (TES) are the chosen technology for the detectors array of the X-ray Integral Field Unit (X-IFU) on board of Athena. The X-IFU is a 2-D imaging integral-field spectrometer operating in the soft X-ray band (0.3-12 keV). The detector consists of an array of 3840 TESs coupled to X-ray absorbers and read out in the MHz bandwidth using Frequency Domain Multiplexing (FDM) based on Superconducting QUantum Interference Devices (SQUIDs). The proposed design calls for devices with a high filling-factor, high quantum efficiency, relatively high count-rate capability and an energy resolution of 2.5 eV at 5.9 keV. The paper will review the basic principle and the physics of the TES-based microcalorimeters and present the state-of-the art of the FDM read-out.

  6. The Pierre Auger Observatory progress and first results

    SciTech Connect

    Mantsch, Paul M.

    2005-08-01

    The Pierre Auger Observatory was designed for a high statistics, full sky study of cosmic rays at the highest energies. Energy, direction and composition measurements are intended to illuminate the mysteries of the most energetic particles in nature. The Auger Observatory utilizes a surface array together with air fluorescence telescopes which together provide a powerful instrument for air shower reconstruction. The southern part of the Auger Observatory, now under construction in the Province of Mendoza, Argentina, is well over half finished. Active detectors have been recording events for one and a half years. Preliminary results based on this first data set are presented.

  7. Diamond detectors with laser induced surface graphite electrodes

    NASA Astrophysics Data System (ADS)

    Komlenok, M.; Bolshakov, A.; Ralchenko, V.; Konov, V.; Conte, G.; Girolami, M.; Oliva, P.; Salvatori, S.

    2016-11-01

    We report on the response of metal-less CVD polycrystalline-diamond pixel sensors under β-particles irradiation. A 21×21 array of 0.18×0.18 mm2 pixels was realized on one side of a 10.0×10.0×0.5 mm3 polycrystalline diamond substrate by means of laser induced surface graphitization. With the same technique, a large graphite contact, used for detector biasing, was fabricated on the opposite side. A coincidence detecting method was used with two other reference polycrystalline diamond detectors for triggering, instead of commonly used scintillators, positioned in the front and on the back of the sensor-array with respect to the impinging particles trajectory. The collected charge distribution at each pixel was analyzed as a function of the applied bias. No change in the pulse height distribution was recorded by inverting the bias voltage polarity, denoting contacts ohmicity and symmetry. A fairly good pixel response uniformity was obtained: the collected charge most probable value saturates for all the pixels at an electric field strength of about ±0.6 V/μm. Under saturation condition, the average collected charge was equal to =1.64±0.02 fC, implying a charge collection distance of about 285 μm. A similar result, within 2%, was also obtained for 400 MeV electrons at beam test facility at INFN Frascati National Laboratory. Experimental results highlighted that more than 84% of impinging particles involved only one pixel, with no significant observed cross-talk effects.

  8. Detectors

    DOEpatents

    Orr, Christopher Henry; Luff, Craig Janson; Dockray, Thomas; Macarthur, Duncan Whittemore; Bounds, John Alan; Allander, Krag

    2002-01-01

    The apparatus and method provide techniques through which both alpha and beta emission determinations can be made simultaneously using a simple detector structure. The technique uses a beta detector covered in an electrically conducting material, the electrically conducting material discharging ions generated by alpha emissions, and as a consequence providing a measure of those alpha emissions. The technique also offers improved mountings for alpha detectors and other forms of detectors against vibration and the consequential effects vibration has on measurement accuracy.

  9. Grand Observatory

    NASA Technical Reports Server (NTRS)

    Young, Eric W.

    2002-01-01

    Various concepts have been recently presented for a 100 m class astronomical observatory. The science virtues of such an observatory are many: resolving planets orbiting around other stars, resolving the surface features of other stars, extending our temporal reach back toward the beginning (at and before stellar and galactic development), improving on the Next Generation Space Telescope, and other (perhaps as yet) undiscovered purposes. This observatory would be a general facility instrument with wide spectral range from at least the near ultraviolet to the mid infrared. The concept espoused here is based on a practical, modular design located in a place where temperatures remain (and instruments could operate) within several degrees of absolute zero with no shielding or cooling. This location is the bottom of a crater located near the north or south pole of the moon, most probably the South Polar Depression. In such a location the telescope would never see the sun or the earth, hence the profound cold and absence of stray light. The ideal nature of this location is elaborated herein. It is envisioned that this observatory would be assembled and maintained remotely through the use of expert robotic systems. A base station would be located above the crater rim with (at least occasional) direct line-of-sight access to the earth. Certainly it would be advantageous, but not absolutely essential, to have humans travel to the site to deal with unexpected contingencies. Further, observers and their teams could eventually travel there for extended observational campaigns. Educational activities, in general, could be furthered thru extended human presence. Even recreational visitors and long term habitation might follow.

  10. The solid angle (geometry factor) for a spherical surface source and an arbitrary detector aperture

    DOE PAGES

    Favorite, Jeffrey A.

    2016-01-13

    It is proven that the solid angle (or geometry factor, also called the geometrical efficiency) for a spherically symmetric outward-directed surface source with an arbitrary radius and polar angle distribution and an arbitrary detector aperture is equal to the solid angle for an isotropic point source located at the center of the spherical surface source and the same detector aperture.

  11. Using star tracks to determine the absolute pointing of the Fluorescence Detector telescopes of the Pierre Auger Observatory

    SciTech Connect

    De Donato, Cinzia; Sanchez, Federico; Santander, Marcos; Natl.Tech.U., San Rafael; Camin, Daniel; Garcia, Beatriz; Grassi, Valerio; /Milan U. /INFN, Milan

    2005-05-01

    To accurately reconstruct a shower axis from the Fluorescence Detector data it is essential to establish with high precision the absolute pointing of the telescopes. To d that they calculate the absolute pointing of a telescope using sky background data acquired during regular data taking periods. The method is based on the knowledge of bright star's coordinates that provide a reliable and stable coordinate system. it can be used to check the absolute telescope's pointing and its long-term stability during the whole life of the project, estimated in 20 years. They have analyzed background data taken from January to October 2004 to determine the absolute pointing of the 12 telescopes installed both in Los Leones and Coihueco. The method is based on the determination of the mean-time of the variance signal left by a star traversing a PMT's photocathode which is compared with the mean-time obtained by simulating the track of that star on the same pixel.

  12. Energy spectrum measured by the telescope array surface detector

    NASA Astrophysics Data System (ADS)

    Ivanov, Dmitri

    2012-05-01

    Two conflicting measurements of the ultra high energy cosmic ray (UHECR) flux have been reported by the Akeno Giant Air Shower Array (AGASA) and the High Resolution Fly's Eye (HiRes) experiments. HiRes observes a ˜5sigma suppression at E = 1019.75 eV, which is in agreement with the prediction of Greisen-Zatsepin-Kuz'min (GZK) theory. AGASA, in contrast, sees the flux extended well beyond E = 1020 eV with no visible break, suggesting that the flux is limited only by the rate at which the sources can produce the UHECR and not by interaction of energetic particles with the cosmic microwave background, thus challenging the relativistic invariance principle. In response to this discrepancy, a new experiment named the Telescope Array (TA) has been deployed, which combines the detection elements used separately by HiRes and AGASA. We describe the TA surface detector (SD) analysis using a technique new to the field, which consists of a detailed Monte-Carlo (MC) simulation of the SD response to the natural cosmic rays, validating the MC by comparing its distributions with the data, and calculation of the SD aperture from the MC. We will also describe our reconstruction procedure, based solely upon the data, and its application to both data and the MC. Finally, we will describe the energy spectrum resulting from this analysis, which is found to be in excellent agreement with the HiRes result, and as such, is the first confirmation of the GZK effect by a ground array of scintillation counters.

  13. Dual instrument for Flare and CME onset observations - Double solar Coronagraph with Solar Chromospheric Detector and Coronal Multi-channel Polarimeter at Lomnicky stit Observatory

    NASA Astrophysics Data System (ADS)

    Kucera, Ales; Tomczyk, Steven; Rybak, Jan; Sewell, Scott; Gomory, Peter; Schwartz, Pavol; Ambroz, Jaroslav; Kozak, Matus

    2015-08-01

    We report on unique dual instrument developed for simultaneous measurements of velocity and magnetic fields in the solar chromosphere and corona. We describe the technical parameters and capability of the Coronal Multi-channel Polarimeter (CoMP-S) and Solar Chromospheric detector (SCD) mounted at the Double solar coronagraph at Lomnicky Stit Observatory and working simultaneously with strictly parallel pointing of both coronagraphs. The CoMP-S is 2D spectropolarimeter designed for observations of VIS and near-IR emission lines of prominences and corona with operating spectral range: 500 - 1100 nm, sequential measurement of several VIS and near-IR lines. Its field of view is 14 arcmin x 11 arcmin. It consists of 4-stage calcite Lyot filter followed by the ferro-liquid crystal polarizer and four cameras (2 visible, 2 infrared). The capability is to deliver 2D full Stokes I, Q, U, V, using registration with 2 IR cameras (line + background) and 2 VIS cameras (line + background) SCD is a single beam instrument to observe bright chromosphere. It is a combination of tunable filter and polarimeter. Spectral resolution of the SCD ranges from 0.046 nm for observations of the HeI 1083 nm line up to to 25 pm is for observation of the HeI 587.6 nm line. The birefringent filter of the SCD has high spectral resolution, as well as spatial resolution (1.7 arcseconds) and temporal resolution (10 seconds) First results are also reported and discussed.

  14. Integrated Studies of Atmosphere-Surface Exchanges and Processes at the Tiksi Hydrometeorological Observatory in the Russian Far East

    NASA Astrophysics Data System (ADS)

    Uttal, Taneil; Makshtas, Alexander; Laurila, Tuomas

    2013-04-01

    The Tiksi Hydrometeorological Observatory facility has been developed over the last 6 years through a partnership between Russian, U.S. and Finnish agencies responsible for environmental monitoring. The current facility has a clean air facility, a 20 meter tower and an upgraded weather station. Measurements are being made of LW/SW radiation, climate grade meteorological parameters, turbulent fluxes, CO2, methane, aerosols, H2O, greenhouse gases (via flask sampling), black carbon, ozone, surface temperatures and permafrost active layer temperature profiles. Tiksi is located in a boundary region at the confluence of Atlantic and Pacific influences on the Arctic atmosphere; this results in a wide variety of air masses with variable cloud, aerosol and pollutant characteristics in the vicinity of the Tiksi Hydrometeorological Observatory creating a natural laboratory to study the influence that the various source regions of Russia, Northern America, Europe and Central Asia have on regional boundary layer processes. Tiksi is on the edge of the Laptev Sea that is an area of such large ice production that it has been termed "the ice factory of the Arctic Ocean" providing much of the sea ice in the Arctic Ocean. Thus the observatory sensors are frequently influenced by the maritime as well as continental air which is already showing up in multiple data lines as having distinctive properties. An integrated picture is emerging of ozone depletion events, black carbon on snow impacts, methane and CO2 flux seasonal variability, and short-lived temperature events that can be interpreted in the context of feed-backs with the local off-shore ice conditions and on-shore active layer morphology. This presentation summaries preliminary results with an emphasis on identifying linkages being study lines that are typically conducted separately.

  15. The Landscape Evolution Observatory: a large-scale controllable infrastructure to study coupled Earth-surface processes

    USGS Publications Warehouse

    Pangle, Luke A.; DeLong, Stephen B.; Abramson, Nate; Adams, John; Barron-Gafford, Greg A.; Breshears, David D.; Brooks, Paul D.; Chorover, Jon; Dietrich, William E.; Dontsova, Katerina; Durcik, Matej; Espeleta, Javier; Ferre, T. P. A.; Ferriere, Regis; Henderson, Whitney; Hunt, Edward A.; Huxman, Travis E.; Millar, David; Murphy, Brendan; Niu, Guo-Yue; Pavao-Zuckerman, Mitch; Pelletier, Jon D.; Rasmussen, Craig; Ruiz, Joaquin; Saleska, Scott; Schaap, Marcel; Sibayan, Michael; Troch, Peter A.; Tuller, Markus; van Haren, Joost; Zeng, Xubin

    2015-01-01

    Zero-order drainage basins, and their constituent hillslopes, are the fundamental geomorphic unit comprising much of Earth's uplands. The convergent topography of these landscapes generates spatially variable substrate and moisture content, facilitating biological diversity and influencing how the landscape filters precipitation and sequesters atmospheric carbon dioxide. In light of these significant ecosystem services, refining our understanding of how these functions are affected by landscape evolution, weather variability, and long-term climate change is imperative. In this paper we introduce the Landscape Evolution Observatory (LEO): a large-scale controllable infrastructure consisting of three replicated artificial landscapes (each 330 m2 surface area) within the climate-controlled Biosphere 2 facility in Arizona, USA. At LEO, experimental manipulation of rainfall, air temperature, relative humidity, and wind speed are possible at unprecedented scale. The Landscape Evolution Observatory was designed as a community resource to advance understanding of how topography, physical and chemical properties of soil, and biological communities coevolve, and how this coevolution affects water, carbon, and energy cycles at multiple spatial scales. With well-defined boundary conditions and an extensive network of sensors and samplers, LEO enables an iterative scientific approach that includes numerical model development and virtual experimentation, physical experimentation, data analysis, and model refinement. We plan to engage the broader scientific community through public dissemination of data from LEO, collaborative experimental design, and community-based model development.

  16. The Landscape Evolution Observatory: A large-scale controllable infrastructure to study coupled Earth-surface processes

    NASA Astrophysics Data System (ADS)

    Pangle, Luke A.; DeLong, Stephen B.; Abramson, Nate; Adams, John; Barron-Gafford, Greg A.; Breshears, David D.; Brooks, Paul D.; Chorover, Jon; Dietrich, William E.; Dontsova, Katerina; Durcik, Matej; Espeleta, Javier; Ferre, T. P. A.; Ferriere, Regis; Henderson, Whitney; Hunt, Edward A.; Huxman, Travis E.; Millar, David; Murphy, Brendan; Niu, Guo-Yue; Pavao-Zuckerman, Mitch; Pelletier, Jon D.; Rasmussen, Craig; Ruiz, Joaquin; Saleska, Scott; Schaap, Marcel; Sibayan, Michael; Troch, Peter A.; Tuller, Markus; van Haren, Joost; Zeng, Xubin

    2015-09-01

    Zero-order drainage basins, and their constituent hillslopes, are the fundamental geomorphic unit comprising much of Earth's uplands. The convergent topography of these landscapes generates spatially variable substrate and moisture content, facilitating biological diversity and influencing how the landscape filters precipitation and sequesters atmospheric carbon dioxide. In light of these significant ecosystem services, refining our understanding of how these functions are affected by landscape evolution, weather variability, and long-term climate change is imperative. In this paper we introduce the Landscape Evolution Observatory (LEO): a large-scale controllable infrastructure consisting of three replicated artificial landscapes (each 330 m2 surface area) within the climate-controlled Biosphere 2 facility in Arizona, USA. At LEO, experimental manipulation of rainfall, air temperature, relative humidity, and wind speed are possible at unprecedented scale. The Landscape Evolution Observatory was designed as a community resource to advance understanding of how topography, physical and chemical properties of soil, and biological communities coevolve, and how this coevolution affects water, carbon, and energy cycles at multiple spatial scales. With well-defined boundary conditions and an extensive network of sensors and samplers, LEO enables an iterative scientific approach that includes numerical model development and virtual experimentation, physical experimentation, data analysis, and model refinement. We plan to engage the broader scientific community through public dissemination of data from LEO, collaborative experimental design, and community-based model development.

  17. Beta Cage: A New, Large-Area Multi-Wire Screening Detector For Surface Beta Contamination

    SciTech Connect

    Shutt, T.; Schnee, R.W.; Dahl, C.E.; Viveiros, L. de; Gaitskell, R.J.

    2005-09-08

    We report on a design study for a new, dedicated, low-radioactive-background screening detector for low-energy beta-emitting contamination on surfaces. The detector, a large-area gaseous detector with multi-wire proportional readout, has sufficient sensitivity to screen materials at the level needed for the proposed SuperCDMS 1 ton dark matter experiment. Such capability does not currently exist. This detector would have additional applications in low-radioactive-background physics experiments, and radioactive trace analysis, such as 14C dating.

  18. Heated Surface Temperatures Measured by Infrared Detector in a Cascade Environment

    NASA Technical Reports Server (NTRS)

    Boyle, Robert J.

    2002-01-01

    Investigators have used infrared devices to accurately measure heated surface temperatures. Several of these applications have been for turbine heat transfer studies involving film cooling and surface roughness, typically, these measurements use an infrared camera positioned externally to the test section. In cascade studies, where several blades are used to ensure periodic flow, adjacent blades block the externally positioned camera's views of the test blade. To obtain a more complete mapping of the surface temperatures, researchers at the NASA Glenn Research Center fabricated a probe with an infrared detector to sense the blade temperatures. The probe size was kept small to minimize the flow disturbance. By traversing and rotating the probe, using the same approach as for total pressure surveys, one can find the blade surface temperatures. Probe mounted infrared detectors are appropriate for measuring surface temperatures where an externally positioned infrared camera is unable to completely view the test object. This probe consists of a 8-mm gallium arsenide (GaAs) lens mounted in front of a mercury-cadmium-zinc-tellurium (HgCdZnTe) detector. This type of photovoltaic detector was chosen because of its high sensitivity to temperature when the detector is uncooled. The particular application is for relatively low surface temperatures, typically ambient to 100 C. This requires a detector sensitive at long wavelengths. The detector is a commercial product enclosed in a 9-mm-diameter package. The GaAs lens material was chosen because of its glass-like hardness and its good long-wavelength transmission characteristics. When assembled, the 6.4-mm probe stem is held in the traversing actuator. Since the entire probe is above the measurement plane, the flow field disturbance in the measurement plane is minimized. This particular probe body is somewhat wider than necessary, because it was designed to have replaceable detectors and lenses. The signal for the detector is

  19. Astronomical observatory for shuttle. Phase A study

    NASA Technical Reports Server (NTRS)

    Guthals, D. L.

    1973-01-01

    The design, development, and configuration of the astronomical observatory for shuttle are discussed. The characteristics of the one meter telescope in the spaceborne observatory are described. A variety of basic spectroscopic and image recording instruments and detectors which will permit a large variety of astronomical observations are reported. The stDC 37485elines which defined the components of the observatory are outlined.

  20. The Central laser facility at the Pierre Auger Observatory

    SciTech Connect

    Arqueros, F.; Bellido, J.; Covault, C.; D'Urso, D.; Di Giulio, C.; Facal, P.; Fick, B.; Guarino, F.; Malek, M.; Matthews, J.A.J.; Matthews, J.; Meyhandan, R.; Monasor, M.; Mostafa, M.; Petrinca, P.; Roberts, M.; Sommers, P.; Travnicek, P.; Valore, L.; Verzi, V.; Wiencke, Lawrence; /Utah U.

    2005-07-01

    The Central Laser Facility is located near the middle of the Pierre Auger Observatory in Argentina. It features a UV laser and optics that direct a beam of calibrated pulsed light into the sky. Light scattered from this beam produces tracks in the Auger optical detectors which normally record nitrogen fluorescence tracks from cosmic ray air showers. The Central Laser Facility provides a ''test beam'' to investigate properties of the atmosphere and the fluorescence detectors. The laser can send light via optical fiber simultaneously to the nearest surface detector tank for hybrid timing analyses. We describe the facility and show some examples of its many uses.

  1. Carnegie Observatories

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    The Carnegie Observatories were founded in 1902 by George Ellery Hale. Their first facility was the MOUNT WILSON OBSERVATORY, located in the San Gabriel Mountains above Pasadena, California. Originally a solar observatory, it moved into stellar, galactic and extragalactic research with the construction of the 60 in (1.5 m), and 100 in (2.5 m) telescopes, each of which was the largest in the world...

  2. Method for growing a back surface contact on an imaging detector used in conjunction with back illumination

    NASA Technical Reports Server (NTRS)

    Blacksberg, Jordana (Inventor); Hoenk, Michael Eugene (Inventor); Nikzad, Shouleh (Inventor)

    2010-01-01

    A method is provided for growing a back surface contact on an imaging detector used in conjunction with back illumination. In operation, an imaging detector is provided. Additionally, a back surface contact (e.g. a delta-doped layer, etc.) is grown on the imaging detector utilizing a process that is performed at a temperature less than 450 degrees Celsius.

  3. EFFECT OF SURFACE PREPARATION TECHNIQUE ON THE RADIATION DETECTOR PERFORMANCEOF CDZNTE

    SciTech Connect

    Duff, M

    2007-05-23

    Synthetic CdZnTe (CZT) semiconducting crystals are highly suitable for the room temperature-based detection of gamma radiation. The surface preparation of Au contacts on surfaces of CZT detectors is typically conducted after (1) polishing to remove artifacts from crystal sectioning and (2) chemical etching, which removes residual mechanical surface damage however etching results in a Te rich surface layer that is prone to oxidize. Our studies show that CZT surfaces that are only polished (as opposed to polished and etched) can be contacted with Au and will yield lower surface currents. Due to their decreased dark currents, these as-polished surfaces can be used in the fabrication of gamma detectors exhibiting a higher performance than polished and etched surfaces with relatively less peak tailing and greater energy resolution. CdZnTe or ''CZT'' crystals are attractive to use in homeland security applications because they detect radiation at room temperature and do not require low temperature cooling as with silicon- and germanium-based detectors. Relative to germanium and silicon detectors, CZT is composed of higher Z elements and has a higher density, which gives it greater ''stopping power'' for gamma rays making a more efficient detector. Single crystal CZT materials with high bulk resistivity ({rho}>10{sup 10} {Omega} x cm) and good mobility-lifetime products are also required for gamma-ray spectrometric applications. However, several factors affect the detector performance of CZT are inherent to the as grown crystal material such as the presence of secondary phases, point defects and the presence of impurities (as described in a literature review by R. James and researchers). These and other factors can limit radiation detector performance such as low resistivity, which causes a large electronic noise and the presence of traps and other heterogeneities, which result in peak tailing and poor energy resolution.

  4. Understanding the Spatiotemporal Structures in Atmosphere-Land Surface Exchange at the Jülich Observatory for Cloud Evolution

    NASA Astrophysics Data System (ADS)

    Marke, T.; Crewell, S.; Loehnert, U.; Rascher, U.; Schween, J. H.

    2015-12-01

    This study aims at identifying spatial and temporal patterns of surface-atmosphere exchange parameters from highly-resolved and long-term observations. For this purpose, a combination of continuous ground-based measurements and dedicated aircraft campaigns using state-of-the-art remote sensing instrumentation at the Jülich Observatory for Cloud Evolution (JOYCE) is available. JOYCE provides a constantly growing multi-year data set for detailed insight into boundary layer processes and patterns related to surface conditions since 2011. The JOYCE site is embedded in a rural environment with different crop types. The availability of a scanning microwave radiometer and cloud radar is a unique component of JOYCE. The hemispheric scans of the ground-based radiometer allow the identification and quantification of horizontal gradients in water vapor and liquid water path measurements. How these gradients are connected to near-surface fluxes and the topography depending on the mean wind flow and surface fluxes is investigated by exploring the long-term data set. Additionally, situations with strong coupling to the surface can be identified by observing the atmospheric turbulence and stability within the boundary layer, using different lidar systems. Furthermore, the influence of thin liquid water clouds, which are typical for the boundary layer development, on the radiation field and the interaction with the vegetation is examined. Applying a synergistic statistical retrieval approach, using passive microwave and infrared observations, shows an improvement in retrieving thin liquid cloud microphysical properties. The role of vegetation is assessed by exploiting the time series of the sun-induced chlorophyll fluorescence (SIF) signal measured at the ground level using automated measurements. For selected case studies, a comparison to maps of hyperspectral reflectance and SIF obtained from an airborne high-resolution imaging spectrometer is realized.

  5. Surface ozone distributions and variations from 1973-1984: Measurements at the NOAA Geophysical Monitoring for Climatic Change Baseline Observatories

    NASA Astrophysics Data System (ADS)

    Oltmans, Samuel J.; Komhyr, Walter D.

    1986-04-01

    Surface ozone data are presented from up to 12 years of continuous measurements at Point Barrow, Alaska; Mauna Loa, Hawaii; American Samoa, South Pacific; and South Pole, Antarctica. Annual cycle characteristics of the data are described relative to atmospheric mixing and transport processes that give rise to the observed annual ozone distributions. Both positive and negative long-term trends are exhibited by the data. From examination of trends in the seasonal and monthly data, it is concluded that the cause of the trends is most likely a fluctuation over the years in the stratospheric-tropospheric exchange and tropospheric circulation processes that distribute ozone within the troposphere, coupled with tropospheric circulation disturbances such as those associated with the El Niño/Southern Oscillation events of 1976 and 1982-1983. Because the positive ozone trend at Barrow occurs during summer months, photochemical ozone production in increasingly polluted Arctic air cannot be ruled out. Ozonesonde data are used to show that the surface ozone observations at Mauna Loa observatory in the downslope wind regimes, and at South Pole, are representative of ozone measurements in the free troposphere, and that the ozone trends observed at Point Barrow and Samoa are likely representative of the lower free troposphere even though the measurements are made in air modified within the boundary layer.

  6. Astronomical observatories

    NASA Technical Reports Server (NTRS)

    Ponomarev, D. N.

    1983-01-01

    The layout and equipment of astronomical observatories, the oldest scientific institutions of human society are discussed. The example of leading observatories of the USSR allows the reader to familiarize himself with both their modern counterparts, as well as the goals and problems on which astronomers are presently working.

  7. Measurements of Physical and Gas Exchanges between the Atmosphere and Surface at the Tiksi Hydrometeorological Observatory

    NASA Astrophysics Data System (ADS)

    Uttal, T.; Grachev, A. A.; Makshtas, A. P.; Repina, I.; Persson, O. P.; Laurila, T. J.; Crepinsek, S.

    2013-12-01

    In recent years a number of Arctic stations have installed micro-meteorological towers in recognition of the need to explicitly quantify the detailed exchanges between the surface and the atmosphere. One of the newer installations is a 20 meter tower in Tiksi, Russia that is located at 71.58N, 128.92E in the Russian Far East. The Tiksi tower is equipped with temperature, humidity and wind sensors at several levels (allowing the calculation of turbulent heat fluxes and fine scale characterization of the near-surface boundary layer) and H2O/CO2 sensors, It is located in near proximity to measurements of incoming and outgoing solar radiation (allowing energy balance calculations), and CH4 sensors, surface O3 measurements (allowing detection of ozone depletion events), and ancillary measurements of snow depth and permafrost active layer temperature profiles. An integrated analysis will look at the variability of these physical and chemical exchanges and variations over one annual cycle with an emphasis on detecting connections and linkages. This network of measurements supports the International Arctic Systems for Observing the Atmosphere (www.iasoa.org) and Global Cryosphere Watch (http://globalcryospherewatch.org/)

  8. Rejection of Alpha Surface Background in Non-scintillating Bolometric Detectors: The ABSuRD Project

    NASA Astrophysics Data System (ADS)

    Biassoni, M.; Brofferio, C.; Bucci, C.; Canonica, L.; di Vacri, M. L.; Gorla, P.; Pavan, M.; Yeh, M.

    2016-08-01

    Due to their excellent energy resolution values and the vast choice of possible materials, bolometric detectors are currently widely used in the physics of rare events. A limiting aspect for bolometers rises from their inability to discriminate among radiation types or surface from bulk events. It has been demonstrated that the main limitation to sensitivity for purely bolometric detectors is represented by surface alpha contaminations, causing a continuous background that cannot be discriminated. A new scintillation-based technique for the rejection of surface alpha background in non-scintillating bolometric experiments is proposed in this work. The idea is to combine a scintillating and a high sensitivity photon detector with a non-scintillating absorber. We present results showing the possibility to reject events due to alpha decay at or nearby the surface of the crystal.

  9. Detection of very inclined showers with the Auger Observatory

    SciTech Connect

    Nellen, Lukas; /Mexico U., ICN

    2005-07-01

    The Pierre Auger Observatory can detect air showers with high efficiency at large zenith angles with both the fluorescence and surface detectors. Since half the available solid angle corresponds to zeniths between 60 and 90 degrees, a large number of inclined events can be expected and are indeed observed. In this paper, we characterize the inclined air showers detected by the Observatory and we present the aperture for inclined showers and an outlook of the results that can be obtained in future studies of the inclined data set.

  10. Study of cloud enhanced surface UV radiation at the atmospheric observatory of Southern Patagonia, Río Gallegos, Argentina

    NASA Astrophysics Data System (ADS)

    Wolfram, Elian A.; Salvador, Jacobo; Orte, Facundo; Bulnes, Daniela; D'Elia, Raul; Antón, Manuel; Alados-Arboledas, Lucas; Quel, Eduardo

    2013-05-01

    Ozone and ultraviolet (UV) radiation are two important issues in the study of Earth's atmosphere. The anthropogenic perturbation of the ozone layer has induced change in the amount of UV radiation that reaches the Earth's surface, mainly through the Antarctic ozone hole. Also clouds have been identified as the main modulator of UV amount over short time scales. While clouds can decrease direct radiation, they can produce an increase in the diffuse component, and as a consequence the surface UV radiation may be higher than during an equivalent clear sky scenario. In particular this situation can be important when a low ozone column and partially cloud coverered skies occur simultaneously. These situations happen frequently in southern Patagonia, where the CEILAP Lidar Division has established the Atmospheric Observatory of Southern Patagonia, an atmospheric remote sensing site near the city of Río Gallegos (51°55'S, 69°14'W). In this paper, the impact of clouds on UV radiation is investigated by the use of ground based measurements from the passive remote sensing instruments operating at this site, mainly broad and moderate narrow band filter radiometers. Cloud modification factors (CMF, ratio between the measured UV radiation in a cloudy sky and the simulated radiation under cloud-free conditions) are evaluated for the study site. CMFs higher than 1 are found during spring and summer time, when lower total ozone columns, higher solar elevations and high cloud cover occur simultaneously, producing extreme erythemal irradiance at the ground surface. Enhancements as high as 25% were registered. The maximum duration of the enhancement was around 30 minutes. This produces dangerous sunbathing conditions for the Río Gallegos citizen.

  11. Surface Passivation of CdZnTe Detector by Hydrogen Peroxide Solution Etching

    NASA Technical Reports Server (NTRS)

    Hayes, M.; Chen, H.; Chattopadhyay, K.; Burger, A.; James, R. B.

    1998-01-01

    The spectral resolution of room temperature nuclear radiation detectors such as CdZnTe is usually limited by the presence of conducting surface species that increase the surface leakage current. Studies have shown that the leakage current can be reduced by proper surface preparation. In this study, we try to optimize the performance of CdZnTe detector by etching the detector with hydrogen peroxide solution as function of concentration and etching time. The passivation effect that hydrogen peroxide introduces have been investigated by current-voltage (I-V) measurement on both parallel strips and metal-semiconductor-metal configurations. The improvements on the spectral response of Fe-55 and 241Am due to hydrogen peroxide treatment are presented and discussed.

  12. Analysis of Surface Chemistry and Detector Performance of Chemically Process CdZnTe crystals

    SciTech Connect

    HOSSAIN, A.; Yang, G.; Sutton, J.; Zergaw, T.; Babalola, O. S.; Bolotnikov, A. E.; Camarda. ZG. S.; Gul, R.; Roy, U. N., and James, R. B.

    2015-10-05

    The goal is to produce non-conductive smooth surfaces for fabricating low-noise and high-efficiency CdZnTe devices for gamma spectroscopy. Sample preparation and results are discussed. The researachers demonstrated various bulk defects (e.g., dislocations and sub-grain boundaries) and surface defects, and examined their effects on the performance of detectors. A comparison study was made between two chemical etchants to produce non-conductive smooth surfaces. A mixture of bromine and hydrogen peroxide proved more effective than conventional bromine etchant. Both energy resolution and detection efficiency of CZT planar detectors were noticeably increased after processing the detector crystals using improved chemical etchant and processing methods.

  13. Tartu Observatory

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Tartu Observatory (TO) is a research institution in Estonia accommodating the northernmost 1.5 m telescope in the world. It is located in Estonia, about 20 km south-west of Tartu in the village of Tõravere (58°16'08''.4 N, 26°27'32''.4 E). TO performs research in astrophysics and atmospheric physics and popularizes those branches of science. TO was founded in 1808 as an observatory of Tartu Unive...

  14. Taosi Observatory

    NASA Astrophysics Data System (ADS)

    Sun, Xiaochun

    Taosi observatory is the remains of a structure discovered at the later Neolithic Taosi site located in Xiangfen County, Shanxi Province, in north-central China. The structure is a walled enclosure on a raised platform. Only rammed-earth foundations of the structure remained. Archaeoastronomical studies suggest that this structure functioned as an astronomical observatory. Historical circumstantial evidence suggests that it was probably related to the legendary kingdom of Yao from the twenty-first century BC.

  15. The Front-End Cards of the Pierre Auger Surface Detectors: Test Results and Performance in the Field

    NASA Astrophysics Data System (ADS)

    Szadkowski, Z.; Bäcker, T.; Becker, K.-H.; Buchholz, P.; Fleck, I.; Grigat, M.; Kamper, K.-H.; Rammes, M.; Rautenberg, J.; Taşcău, O.

    The Pierre Auger Observatory, presently under construction in Argentina, is nearing completion. The instrument is designed to measure the highest energy cosmic rays with unprecedented resolution and statistics. Its surface array comprises 1600 water Cherenkov detectors distributed over an area of 3000 km2. The Cherenkov light of each tank is detected by three 9-inch photomultipliers from which the signals of the anode and last dynode are digitized each by 10 bit 40 MHz FADCs. An Altera Cyclone FPGA is employed to generate different local triggers and to handle the data transfer to a communication board. The low-power budget, large environmental temperature variations, and the long-term operation impose special constraints to the Front-End cards. After discussing the design of the cards we present an automized test-bench including a climate chamber which has been set up in order to test the large number of boards prior to installation in the field. The qualification procedure and the results obtained in the laboratory are presented. Data collected during operation in the field demonstrate a very good performance and reliability of the Front-End cards.

  16. Land-surface studies with a directional neutron detector.

    SciTech Connect

    Desilets, Darin; Brennan, James S.; Mascarenhas, Nicholas; Marleau, Peter

    2009-09-01

    Direct measurements of cosmic-ray neutron intensity were recorded with a neutron scatter camera developed at SNL. The instrument used in this work is a prototype originally designed for nuclear non-proliferation work, but in this project it was used to characterize the response of ambient neutrons in the 0.5-10 MeV range to water located on or above the land surface. Ambient neutron intensity near the land surface responds strongly to the presence of water, suggesting the possibility of an indirect method for monitoring soil water content, snow water equivalent depth, or canopy intercepted water. For environmental measurements the major advantage of measuring neutrons with the scatter camera is the limited (60{sup o}) field of view that can be obtained, which allows observations to be conducted at a previously unattainable spatial scales. This work is intended to provide new measurements of directional fluxes which can be used in the design of new instruments for passively and noninvasively observing land-surface water. Through measurements and neutron transport modeling we have demonstrated that such a technique is feasible.

  17. Keele Observatory

    NASA Astrophysics Data System (ADS)

    Theodorus van Loon, Jacco; Albinson, James; Bagnall, Alan; Bryant, Lian; Caisley, Dave; Doody, Stephen; Johnson, Ian; Klimczak, Paul; Maddison, Ron; Robinson, StJohn; Stretch, Matthew; Webb, John

    2015-08-01

    Keele Observatory was founded by Dr. Ron Maddison in 1962, on the hill-top campus of Keele University in central England, hosting the 1876 Grubb 31cm refractor from Oxford Observatory. It since acquired a 61cm research reflector, a 15cm Halpha solar telescope and a range of other telescopes. Run by a group of volunteering engineers and students under directorship of a Keele astrophysicist, it is used for public outreach as well as research. About 4,000 people visit the observatory every year, including a large number of children. We present the facility, its history - including involvement in the 1919 Eddington solar eclipse expedition which proved Albert Einstein's theory of general relativity - and its ambitions to erect a radio telescope on its site.

  18. The Pierre Auger Cosmic Ray Observatory

    NASA Astrophysics Data System (ADS)

    Pierre Auger Collaboration

    2015-10-01

    The Pierre Auger Observatory, located on a vast, high plain in western Argentina, is the world's largest cosmic ray observatory. The objectives of the Observatory are to probe the origin and characteristics of cosmic rays above 1017 eV and to study the interactions of these, the most energetic particles observed in nature. The Auger design features an array of 1660 water Cherenkov particle detector stations spread over 3000 km2 overlooked by 24 air fluorescence telescopes. In addition, three high elevation fluorescence telescopes overlook a 23.5 km2, 61-detector infilled array with 750 m spacing. The Observatory has been in successful operation since completion in 2008 and has recorded data from an exposure exceeding 40,000 km2 sr yr. This paper describes the design and performance of the detectors, related subsystems and infrastructure that make up the Observatory.

  19. WNCC Observatory

    NASA Astrophysics Data System (ADS)

    Snyder, L. F.

    2003-05-01

    Western Nevada Community College (WNCC), located in Carson City, Nevada, is a small two year college with only 6,000 students. Associate degrees and Cer- tificates of Achievement are awarded. The college was built and started classes in 1971 and about 12 years ago the chair of the physics department along with a few in administration had dreams of building a small observatory for education. Around that time a local foundation, Nevada Gaming Foundation for Education Excellence, was looking for a beneficiary in the education field to receive a grant. They decided an observatory at the college met their criteria. Grants to the foundation instigated by Senators, businesses, and Casinos and donations from the local public now total $1.3 million. This paper will explain the different facets of building the observatory, the planning, construction, telescopes and equipment decisions and how we think it will operate for the public, education and research. The organization of local volunteers to operate and maintain the observatory and the planned re- search will be explained.

  20. Yellowstone Volcano Observatory

    USGS Publications Warehouse

    Venezky, Dina Y.; Lowenstern, Jacob

    2008-01-01

    Eruption of Yellowstone's Old Faithful Geyser. Yellowstone hosts the world's largest and most diverse collection of natural thermal features, which are the surface expression of magmatic heat at shallow depths in the crust. The Yellowstone system is monitored by the Yellowstone Volcano Observatory (YVO), a partnership among the U.S. Geological Survey (USGS), Yellowstone National Park, and the University of Utah. YVO is one of five USGS Volcano Hazards Program observatories that monitor U.S. volcanoes for science and public safety. Learn more about Yellowstone and YVO at http://volcanoes.usgs.gov/yvo.

  1. X-ray photoemission analysis of chemically modified TlBr surfaces for improved radiation detectors

    DOE PAGES

    Nelson, A. J.; Voss, L. F.; Beck, P. R.; Graff, R. T.; Conway, A. M.; Nikolic, R. J.; Payne, S. A.; Lee, J. -S.; Kim, H.; Cirignano, L.; et al

    2013-01-12

    We subjected device-grade TlBr to various chemical treatments used in room temperature radiation detector fabrication to determine the resulting surface composition and electronic structure. As-polished TlBr was treated separately with HCl, SOCl2, Br:MeOH and HF solutions. High-resolution photoemission measurements on the valence band electronic structure and Tl 4f, Br 3d, Cl 2p and S 2p core lines were used to evaluate surface chemistry and shallow heterojunction formation. Surface chemistry and valence band electronic structure were correlated with the goal of optimizing the long-term stability and radiation response.

  2. The hybrid energy spectrum of Telescope Array's Middle Drum Detector and surface array

    NASA Astrophysics Data System (ADS)

    Abbasi, R. U.; Abe, M.; Abu-Zayyad, T.; Allen, M. G.; Anderson, R.; Azuma, R.; Barcikowski, E.; Belz, J. W.; Bergman, D. R.; Blake, S. A.; Cady, R.; Chae, M. J.; Cheon, B. G.; Chiba, J.; Chikawa, M.; Cho, W. R.; Fujii, T.; Fukushima, M.; Goto, T.; Hanlon, W.; Hayashi, Y.; Hayashida, N.; Hibino, K.; Honda, K.; Ikeda, D.; Inoue, N.; Ishii, T.; Ishimori, R.; Ito, H.; Ivanov, D.; Jui, C. C. H.; Kadota, K.; Kakimoto, F.; Kalashev, O.; Kasahara, K.; Kawai, H.; Kawakami, S.; Kawana, S.; Kawata, K.; Kido, E.; Kim, H. B.; Kim, J. H.; Kim, J. H.; Kitamura, S.; Kitamura, Y.; Kuzmin, V.; Kwon, Y. J.; Lan, J.; Lim, S. I.; Lundquist, J. P.; Machida, K.; Martens, K.; Matsuda, T.; Matsuyama, T.; Matthews, J. N.; Minamino, M.; Mukai, K.; Myers, I.; Nagasawa, K.; Nagataki, S.; Nakamura, T.; Nonaka, T.; Nozato, A.; Ogio, S.; Ogura, J.; Ohnishi, M.; Ohoka, H.; Oki, K.; Okuda, T.; Ono, M.; Oshima, A.; Ozawa, S.; Park, I. H.; Pshirkov, M. S.; Rodriguez, D. C.; Rubtsov, G.; Ryu, D.; Sagawa, H.; Sakurai, N.; Sampson, A. L.; Scott, L. M.; Shah, P. D.; Shibata, F.; Shibata, T.; Shimodaira, H.; Shin, B. K.; Shin, H. S.; Smith, J. D.; Sokolsky, P.; Springer, R. W.; Stokes, B. T.; Stratton, S. R.; Stroman, T. A.; Suzawa, T.; Takamura, M.; Takeda, M.; Takeishi, R.; Taketa, A.; Takita, M.; Tameda, Y.; Tanaka, H.; Tanaka, K.; Tanaka, M.; Thomas, S. B.; Thomson, G. B.; Tinyakov, P.; Tkachev, I.; Tokuno, H.; Tomida, T.; Troitsky, S.; Tsunesada, Y.; Tsutsumi, K.; Uchihori, Y.; Udo, S.; Urban, F.; Vasiloff, G.; Wong, T.; Yamane, R.; Yamaoka, H.; Yamazaki, K.; Yang, J.; Yashiro, K.; Yoneda, Y.; Yoshida, S.; Yoshii, H.; Zollinger, R.; Zundel, Z.

    2015-08-01

    The Telescope Array experiment studies ultra high energy cosmic rays using a hybrid detector. Fluorescence telescopes measure the longitudinal development of the extensive air shower generated when a primary cosmic ray particle interacts with the atmosphere. Meanwhile, scintillator detectors measure the lateral distribution of secondary shower particles that hit the ground. The Middle Drum (MD) fluorescence telescope station consists of 14 telescopes from the High Resolution Fly's Eye (HiRes) experiment, providing a direct link back to the HiRes measurements. Using the scintillator detector data in conjunction with the telescope data improves the geometrical reconstruction of the showers significantly, and hence, provides a more accurate reconstruction of the energy of the primary particle. The Middle Drum hybrid spectrum is presented and compared to that measured by the Middle Drum station in monocular mode. Further, the hybrid data establishes a link between the Middle Drum data and the surface array. A comparison between the Middle Drum hybrid energy spectrum and scintillator Surface Detector (SD) spectrum is also shown.

  3. NOvA detector technology with intial performance from the surface prototype

    SciTech Connect

    Muether, M.; /Fermilab

    2011-09-01

    NOvA, the NuMI Off-Axis {nu}{sub e} Appearance experiment, will study {nu}{sub {mu}} {yields} {nu}{sub e} oscillations characterized by the mixing angle {Theta}{sub 13}. Provided {Theta}{sub 13} is large enough, NOvA may ultimately determine the ordering of the neutrino masses and measure CP violation in neutrino oscillations. A complementary pair of detectors will be constructed {approx}14 mrad off beam axis to optimize the energy profile of the neutrinos. This system consists of a surface based 14 kTon liquid scintillator tracking volume located 810 km from the main injector source (NuMI) in Ash River, Minnesota and a smaller underground 222 Ton near detector at the Fermilab. The first neutrino signals at the Ash River Site are expected prior to the 2012 accelerator shutdown. In the meantime, a near detector surface prototype has been completed and neutrinos from two Fermilab sources have been observed using the same highly segmented PVC and liquid scintillator detector system that will be deployed in the full scale experiment. Design and initial performance characteristics of this prototype system are being fed back into the design for the full NOvA program.

  4. NASA'S Great Observatories

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Why are space observatories important? The answer concerns twinkling stars in the night sky. To reach telescopes on Earth, light from distant objects has to penetrate Earth's atmosphere. Although the sky may look clear, the gases that make up our atmosphere cause problems for astronomers. These gases absorb the majority of radiation emanating from celestial bodies so that it never reaches the astronomer's telescope. Radiation that does make it to the surface is distorted by pockets of warm and cool air, causing the twinkling effect. In spite of advanced computer enhancement, the images finally seen by astronomers are incomplete. NASA, in conjunction with other countries' space agencies, commercial companies, and the international community, has built observatories such as the Hubble Space Telescope, the Compton Gamma Ray Observatory, and the Chandra X-ray Observatory to find the answers to numerous questions about the universe. With the capabilities the Space Shuttle provides, scientist now have the means for deploying these observatories from the Shuttle's cargo bay directly into orbit.

  5. Development of a near-infrared detector and a fiber-optic integral field unit for a space solar observatory SOLAR-C

    NASA Astrophysics Data System (ADS)

    Katsukawa, Yukio; Kamata, Yukiko; Anan, Tetsu; Hara, Hirohisa; Suematsu, Yoshinori; Bando, Takamasa; Ichimoto, Kiyoshi; Shimizu, Toshifumi

    2016-07-01

    We are developing a high sensitivity and fast readout near-infrared (NIR) detector and an integral field unit (IFU) for making spectro-polarimetric observations of rapidly varying chromospheric spectrum lines, such as He I 1083 nm and Ca II 854 nm, in the next space-based solar mission SOLAR-C. We made tests of a 1.7 μm cutoff H2RG detector with the SIDECAR ASIC for the application in SOLAR-C. It's important to verify its perfor- mance in the temperature condition around -100 °C, which is hotter than the typical temperature environment used for a NIR detector. We built a system for testing the detector between -70 °C and -140 °C. We verified linearity, read-out noise, and dark current in both the slow and fast readout modes. We found the detector has to be cooled down lower than -100 °C because of significant increase of the number of hot pixels in the hotter environment. The compact and polarization maintenance IFU was designed using fiber-optic ribbons consisting of rectangular cores which exhibit good polarization maintenance. A Silicone adhesive DC-SE9187L was used to hold the fragile fiber-optic ribbons in a metal housing. Polarization maintenance property was confirmed though polarization calibration as well as temperature control are required to suppress polarization crosstalk and to achieve the polarization accuracy in SOLAR-C.

  6. Determination of sultopride and tiapride in serum by gas chromatography using a surface ionisation detector.

    PubMed

    Kamizono, A; Inotsume, N; Miyamoto, K; Ueda, K; Miyakawa, T; Arimoto, H; Nakano, M

    1991-06-14

    A sensitive and selective method has been developed for the determination of sultopride and tiapride in serum using gas chromatography with a surface ionisation detector. No interfering peaks from endogenous substances were observed. The method showed good reproducibility and accuracy, and the standard curve was linear up to 2 micrograms/ml with a correlation coefficient of 0.999. This method is applicable to pharmacokinetic studies and therapeutic drug monitoring of sultopride and tiapride.

  7. Hanohano: Hawaiian antineutrino observatory

    NASA Astrophysics Data System (ADS)

    Maricic, Jelena; Hanohano Collaboration

    2010-01-01

    Design studies are underway for the deep ocean antineutrino observatory Hanohano. The 10 kton monolitic underwater detector will be able to make precision measurement of neutrino mixing parameters (including θ13 and neutrino mass hierarchy) if stationed around 60 km offshore, from the nuclear reactor. Hanohano will be a mobile detector and placing it in a mid-Pacific location will provide the first ever flux measurement of geoneutrinos (antineutrinos emitted in the radioactive decay series of uranium and thorium), coming from the Earth's mantle and perform a sensitivity search for a hypothetical natural fission reactor in the Earth's core. Additional deployment at a different mid-ocean location will lead to tests of lateral heterogeneity of uranium and thorium in the Earth's mantle. These measurements would provide an important insight into deep-Earth geophysics, mantle composition and understanding of the Earth's heat flow and sources of energy inside the Earth.

  8. PASSIVATION OF SEMICONDUCTOR SURFACES FOR IMPROVED RADIATION DETECTORS: X-RAY PHOTOEMISSION ANALYSIS

    SciTech Connect

    Nelson, A; Conway, A; Reinhardt, C; Ferreira, J; Nikolic, R; Payne, S

    2007-12-10

    Surface passivation of device-grade radiation detector materials was investigated using x-ray photoelectron spectroscopy in combination with transport property measurements before and after various chemical treatments. Specifically Br-MeOH (2% Br), KOH with NH{sub 4}F/H{sub 2}O{sub 2} and NH{sub 4}OH solutions were used to etch, reduce and oxidize the surface of Cd{sub (1-x)}Zn{sub x}Te semiconductor crystals. Scanning electron microscopy was used to evaluate the resultant microscopic surface morphology. Angle-resolved high-resolution photoemission measurements on the valence band electronic structure and core lines were used to evaluate the surface chemistry of the chemically treated surfaces. Metal overlayers were then deposited on these chemically treated surfaces and the I-V characteristics measured. The measurements were correlated to understand the effect of interface chemistry on the electronic structure at these interfaces with the goal of optimizing the Schottky barrier height for improved radiation detector devices.

  9. Effect of an alcohol-based caries detector on the surface tension of sodium hypochlorite preparations.

    PubMed

    Rossi-Fedele, Giampiero; Guastalli, Andrea R

    2015-01-01

    The purpose of this study was to evaluate the effect of an alcohol-based caries detector (Kurakay) on the surface tension of a conventional sodium hypochlorite (NaOCl) preparation, and a product containing a surface-active agent (Chlor-XTRA). The surface tensions of the following solutions were tested: NaOCl, a mixture of NaOCl and Kurakay 9:1 w/w, Chlor-XTRA, a mixture of Chlor-XTRA and Kurakay 9:1 w/w. Ten measurements per test solution were made at 20°C, using an optical method called the "Pendant drop method", with a commercially available apparatus. The addition of Kurakay reduced the surface tension for NaOCl (p<0.05) whilst no significant difference was detected for Chlor-XTRA (p>0.05). Statistically significant differences between the NaOCl and Chlor-XTRA groups were found (p<0.05). The addition of an alcohol-based caries detector resulted in a reduction of the original surface tension values for NaOCl only. Taking into account the fact that mixtures of NaOCl and Kurakay have been used to assess the penetration of root canal irrigants in vitro, the related changes in surface tension are a possible source of bias.

  10. Technology Development Plan for the Baseline Detector System of the X-Ray Microcalorimeter Spectrometer (XMS) of the International X-Ray Observatory (IXO)

    NASA Technical Reports Server (NTRS)

    Kilbourne, C. A.; Boriese, W. B.

    2010-01-01

    The primary purpose of this document is to present the technology development plan for the XMS detector system. It covers the current status (including assessment of the Technology Readiness Level, TRL, and a justification of the level assigned), the roadmap to progress to a level between TRL 5 and TRL 6 by the middle of 2012, and an assessment of the associated cost. A secondary purpose of this document is to address the Action Items raised at the XMS Phase-A Study Mid-Term Review that pertain to the detector system (AI #4, #8, and #9).

  11. Short range laser obstacle detector. [for surface vehicles using laser diode array

    NASA Technical Reports Server (NTRS)

    Kuriger, W. L. (Inventor)

    1973-01-01

    A short range obstacle detector for surface vehicles is described which utilizes an array of laser diodes. The diodes operate one at a time, with one diode for each adjacent azimuth sector. A vibrating mirror a short distance above the surface provides continuous scanning in elevation for all azimuth sectors. A diode laser is synchronized with the vibrating mirror to enable one diode laser to be fired, by pulses from a clock pulse source, a number of times during each elevation scan cycle. The time for a given pulse of light to be reflected from an obstacle and received is detected as a measure of range to the obstacle.

  12. Surface dose measurements with commonly used detectors: a consistent thickness correction method.

    PubMed

    Reynolds, Tatsiana A; Higgins, Patrick

    2015-01-01

    The purpose of this study was to review application of a consistent correction method for the solid state detectors, such as thermoluminescent dosimeters (chips (cTLD) and powder (pTLD)), optically stimulated detectors (both closed (OSL) and open (eOSL)), and radiochromic (EBT2) and radiographic (EDR2) films. In addition, to compare measured surface dose using an extrapolation ionization chamber (PTW 30-360) with other parallel plate chambers RMI-449 (Attix), Capintec PS-033, PTW 30-329 (Markus) and Memorial. Measurements of surface dose for 6MV photons with parallel plate chambers were used to establish a baseline. cTLD, OSLs, EDR2, and EBT2 measurements were corrected using a method which involved irradiation of three dosimeter stacks, followed by linear extrapolation of individual dosimeter measurements to zero thickness. We determined the magnitude of correction for each detector and compared our results against an alternative correction method based on effective thickness. All uncorrected surface dose measurements exhibited overresponse, compared with the extrapolation chamber data, except for the Attix chamber. The closest match was obtained with the Attix chamber (-0.1%), followed by pTLD (0.5%), Capintec (4.5%), Memorial (7.3%), Markus (10%), cTLD (11.8%), eOSL (12.8%), EBT2 (14%), EDR2 (14.8%), and OSL (26%). Application of published ionization chamber corrections brought all the parallel plate results to within 1% of the extrapolation chamber. The extrapolation method corrected all solid-state detector results to within 2% of baseline, except the OSLs. Extrapolation of dose using a simple three-detector stack has been demonstrated to provide thickness corrections for cTLD, eOSLs, EBT2, and EDR2 which can then be used for surface dose measurements. Standard OSLs are not recommended for surface dose measurement. The effective thickness method suffers from the subjectivity inherent in the inclusion of measured percentage depth-dose curves and is not

  13. Ice Observatory

    NASA Astrophysics Data System (ADS)

    blugerman, n.

    2015-10-01

    My project is to make ice observatories to perceive astral movements as well as light phenomena in the shape of cosmic rays and heat, for example.I find the idea of creating an observation point in space, that in time will change shape and eventually disappear, in consonance with the way we humans have been approaching the exploration of the universe since we started doing it. The transformation in the elements we use to understand big and small transformations, within the universe elements.

  14. Implementation of Surface Detector Option in SCALE SAS4 Shielding Module

    SciTech Connect

    Broadhead, B.L.; Emmett, M.B.; Tang, J.S.

    1999-11-17

    The Shielding Analysis Sequence No. 4 (SAS4) in the Standardized Cask Analysis and Licensing Evaluation System (SCALE) is designed to aid the novice user in the preparation of detailed three-dimensional models and radiation protection studies of transportation or storage packages containing spent fuel from a nuclear reactor facility. The underlying methodology in these analyses is the Monte Carlo particle-tracking approach as incorporated into the MORSE-SGC computer code. The use of these basic procedures is enhanced via the automatic generation of the biasing parameters in the SAS4 sequence, which dramatically increases the calculational efficiency of most standard shielding problems. Until recently the primary mechanism for dose estimates in SAS4 was the use of point detectors, which were effective for single-dose locations, but inefficient for quantification of dose-rate profiles. This paper describes the implementation of a new surface detector option for SAS4 with automatic discretization of the detector surface into multiple segments or subdetectors. Results from several sample problems are given and discussed.

  15. SU-E-T-91: Correction Method to Determine Surface Dose for OSL Detectors

    SciTech Connect

    Reynolds, T; Higgins, P

    2014-06-01

    Purpose: OSL detectors are commonly used in clinic due to their numerous advantages, such as linear response, negligible energy, angle and temperature dependence in clinical range, for verification of the doses beyond the dmax. Although, due to the bulky shielding envelope, this type of detectors fails to measure skin dose, which is an important assessment of patient ability to finish the treatment on time and possibility of acute side effects. This study aims to optimize the methodology of determination of skin dose for conventional accelerators and a flattening filter free Tomotherapy. Methods: Measurements were done for x-ray beams: 6 MV (Varian Clinac 2300, 10×10 cm{sup 2} open field, SSD = 100 cm) and for 5.5 MV (Tomotherapy, 15×40 cm{sup 2} field, SAD = 85 cm). The detectors were placed at the surface of the solid water phantom and at the reference depth (dref=1.7cm (Varian 2300), dref =1.0 cm (Tomotherapy)). The measurements for OSLs were related to the externally exposed OSLs measurements, and further were corrected to surface dose using an extrapolation method indexed to the baseline Attix ion chamber measurements. A consistent use of the extrapolation method involved: 1) irradiation of three OSLs stacked on top of each other on the surface of the phantom; 2) measurement of the relative dose value for each layer; and, 3) extrapolation of these values to zero thickness. Results: OSL measurements showed an overestimation of surface doses by the factor 2.31 for Varian 2300 and 2.65 for Tomotherapy. The relationships: SD{sup 2300} = 0.68 × M{sup 2300}-12.7 and SDτoμo = 0.73 × Mτoμo-13.1 were found to correct the single OSL measurements to surface doses in agreement with Attix measurements to within 0.1% for both machines. Conclusion: This work provides simple empirical relationships for surface dose measurements using single OSL detectors.

  16. Surface passivation effects on the performance of p-planar HPGe radiation detector

    NASA Astrophysics Data System (ADS)

    Khizar, Muhammad; Wang, Guojian; Mei, Dongming

    2013-03-01

    Surface passivation of HPGe detectors are always critical to reduce or eliminate the surface effects responsible for limiting both the leakage current and breakdown voltages of these devices. Among the critical part of any HPGe detector is the intrinsic surface, where the full bias voltage is applied at 77K. Typically, in order to make these surfaces electrically passive, and to avoid surface leakage currents, a thick layer of SiO2 is deposited by using different high temperature dry/wet deposition techniques. However, surface passivation using such techniques can result modifying the electric field, by compromising the charge collection in the volume near the contact surfaces. Another option is the amorphous germanium (a-Ge), which acts as a passivant as well as bi-polar blocking contacts. In this study, we have designed a controlled experiment to use Ge oxidation contact as a passivation layer by testing the electrical behavior of the crystal after each oxidation treatment. For this, a high quality a-Ge layer (~ 100 nm to 150 nm) is deposited at 1.5x106 torr using low temperature RF plasma sputtering deposition technique. Among the key characteristics of the deposited passivation layer includes the depositions rates, the precursors (pre-mixed (H2 ~ 15% and Ar) flow rates, plasma power, chamber pressure, and target to-substrate distance. We show the results from our study using home grown HPGe crystals at USD. This work is supported by DOE grant DE-FG02-10ER46709 and the state of South Dakota.

  17. Demonstration of surface electron rejection with interleaved germanium detectors for dark matter searches

    SciTech Connect

    Agnese, R.; Balakishiyeva, D.; Saab, T.; Welliver, B.; Anderson, A. J.; Figueroa-Feliciano, E.; Hertel, S. A.; McCarthy, K. A.; Basu Thakur, R.; Bauer, D. A.; Holmgren, D.; Hsu, L.; Loer, B.; Schmitt, R.; Borgland, A.; Brandt, D.; Brink, P. L.; Do Couto E Silva, E.; Godfrey, G. L.; Hasi, J. [SLAC National Accelerator Laboratory Collaboration: The SuperCDMS Collaboration; and others

    2013-10-14

    The SuperCDMS experiment in the Soudan Underground Laboratory searches for dark matter with a 9-kg array of cryogenic germanium detectors. Symmetric sensors on opposite sides measure both charge and phonons from each particle interaction, providing excellent discrimination between electron and nuclear recoils, and between surface and interior events. Surface event rejection capabilities were tested with two {sup 210}Pb sources producing ∼130 beta decays/hr. In ∼800 live hours, no events leaked into the 8–115 keV signal region, giving upper limit leakage fraction 1.7 × 10{sup −5} at 90% C.L., corresponding to < 0.6 surface event background in the future 200-kg SuperCDMS SNOLAB experiment.

  18. Demonstration of Surface Electron Rejection with Interleaved Germanium Detectors for Dark Matter Searches

    SciTech Connect

    Agnese, R.; Anderson, A. J.; Balakishiyeva, D.; Basu Thakur, R.; Bauer, D. A.; Borgland, A.; Brandt, D.; Brink, P. L.; Bunker, R.; Cabrera, B.; Caldwell, D. O.; Cerdeno, D. G.; Chagani, H.; Cherry, M.; Cooley, J.; Cornell, B.; Crewdson, C. H.; Cushman, Priscilla B.; Daal, M.; Di Stefano, P. C.; Do Couto E Silva, E.; Doughty, T.; Esteban, L.; Fallows, S.; Figueroa-Feliciano, E.; Fox, J.; Fritts, M.; Godfrey, G. L.; Golwala, S. R.; Hall, Jeter C.; Harris, H. R.; Hasi, J.; Hertel, S. A.; Hines, B. A.; Hofer, T.; Holmgren, D.; Hsu, L.; Huber, M. E.; Jastram, A.; Kamaev, O.; Kara, B.; Kelsey, M. H.; Kenany, S.; Kennedy, A.; Kenney, C. J.; Kiveni, M.; Koch, K.; Loer, B.; Lopez Asamar, E.; Mahapatra, R.; Mandic, V.; Martinez, C.; McCarthy, K. A.; Mirabolfathi, N.; Moffatt, R. A.; Moore, D. C.; Nadeau, P.; Nelson, R. H.; Novak, L.; Page, K.; Partridge, R.; Pepin, M.; Phipps, A.; Prasad, K.; Pyle, M.; Qiu, H.; Radpour, R.; Rau, W.; Redl, P.; Reisetter, A.; Resch, R. W.; Ricci, Y.; Saab, T.; Sadoulet, B.; Sander, J.; Schmitt, R.; Schneck, K.; Schnee, Richard; Scorza, S.; Seitz, D.; Serfass, B.; Shank, B.; Speller, D.; Tomada, A.; Villano, A. N.; Welliver, B.; Wright, D. H.; Yellin, S.; Yen, J. J.; Young, B. A.; Zhang, J.

    2013-10-17

    The SuperCDMS experiment in the Soudan Underground Laboratory searches for dark matter with a 9-kg array of cryogenic germanium detectors. Symmetric sensors on opposite sides measure both charge and phonons from each particle interaction, providing excellent discrimination between electron and nuclear recoils, and between surface and interior events. Furthermore, surface event rejection capabilities were tested with two 210Pb sources producing ~130 beta decays/hr. We found that in ~800 live hours, no events leaked into the 8–115 keV signal region, giving upper limit leakage fraction 1.7 x 10-5 at 90% C.L., corresponding to<0.6 surface event background in the future 200-kg SuperCDMS SNOLAB experiment.

  19. IonCCD detector for miniature sector-field mass spectrometer: investigation of peak shape and detector surface artifacts induced by keV ion detection.

    PubMed

    Hadjar, Omar; Schlathölter, Thomas; Davila, Stephen; Catledge, Shane A; Kuhn, Ken; Kassan, Scott; Kibelka, Gottfried; Cameron, Chad; Verbeck, Guido F

    2011-10-01

    A recently described ion charge coupled device detector IonCCD (Sinha and Wadsworth, Rev. Sci. Instrum. 76(2), 2005; Hadjar, J. Am. Soc. Mass Spectrom. 22(4), 612-624, 2011) is implemented in a miniature mass spectrometer of sector-field instrument type and Mattauch-Herzog (MH)-geometry (Rev. Sci. Instrum. 62(11), 2618-2620, 1991; Burgoyne, Hieftje and Hites J. Am. Soc. Mass Spectrom. 8(4), 307-318, 1997; Nishiguchi, Eur. J. Mass Spectrom. 14(1), 7-15, 2008) for simultaneous ion detection. In this article, we present first experimental evidence for the signature of energy loss the detected ion experiences in the detector material. The two energy loss processes involved at keV ion kinetic energies are electronic and nuclear stopping. Nuclear stopping is related to surface modification and thus damage of the IonCCD detector material. By application of the surface characterization techniques atomic force microscopy (AFM) and X-ray photoelectrons spectroscopy (XPS), we could show that the detector performance remains unaffected by ion impact for the parameter range observed in this study. Secondary electron emission from the (detector) surface is a feature typically related to electronic stopping. We show experimentally that the properties of the MH-mass spectrometer used in the experiments, in combination with the IonCCD, are ideally suited for observation of these stopping related secondary electrons, which manifest in reproducible artifacts in the mass spectra. The magnitude of the artifacts is found to increase linearly as a function of detected ion velocity. The experimental findings are in agreement with detailed modeling of the ion trajectories in the mass spectrometer. By comparison of experiment and simulation, we show that a detector bias retarding the ions or an increase of the B-field of the IonCCD can efficiently suppress the artifact, which is necessary for quantitative mass spectrometry.

  20. Alignment of sources and detectors on breast surface for noncontact diffuse correlation tomography of breast tumors

    PubMed Central

    Huang, Chong; Lin, Yu; He, Lian; Irwin, Daniel; Szabunio, Margaret M.; Yu, Guoqiang

    2016-01-01

    Noncontact diffuse correlation tomography (ncDCT) is an emerging technology for 3D imaging of deep tissue blood flow distribution without distorting hemodynamic properties. To adapt the ncDCT for imaging in vivo breast tumors, we designed a motorized ncDCT probe to scan over the breast surface. A computer-aided design (CAD)-based approach was proposed to create solid volume mesh from arbitrary breast surface obtained by a commercial 3D camera. The sources and detectors of ncDCT were aligned on the breast surface through ray tracing to mimic the ncDCT scanning with CAD software. The generated breast volume mesh along with the boundary data of ncDCT at the aligned source and detector pairs were used for finite-element-method-based flow image reconstruction. We evaluated the accuracy of source alignments on mannequin and human breasts; largest alignment errors were less than 10% in both tangential and radial directions of scanning. The impact of alignment errors (assigned 10%) on the tumor reconstruction was estimated using computer simulations. The deviations of simulated tumor location and blood flow contrast resulted from the alignment errors were 0.77 mm (less than the node distance of 1 mm) and 1%, respectively, which result in minor impact on flow image reconstruction. Finally, a case study on a human breast tumor was conducted and a tumor-to-normal flow contrast was reconstructed, demonstrating the feasibility of ncDCT in clinical application. PMID:26479823

  1. Estimation of methane emission flux at landfill surface using laser methane detector: Influence of gauge pressure.

    PubMed

    Park, Jin-Kyu; Kang, Jong-Yun; Lee, Nam-Hoon

    2016-08-01

    The aim of this study was to investigate the possibility of measuring methane emission fluxes, using surface methane concentration and gauge pressure, by analyzing the influence of gauge pressure on the methane emission flux and the surface methane concentration, as well as the correlation between the methane emission flux and surface methane concentrations. The surface methane concentration was measured using a laser methane detector. Our results show a positive linear relationship between the surface methane concentration and the methane emission flux. Furthermore, the methane emission flux showed a positive linear relationship with the gauge pressure; this implies that when the surface methane concentration and the surface gauge pressure are measured simultaneously, the methane emission flux can be calculated using Darcy's law. A decrease in the vertical permeability was observed when the gauge pressure was increased, because reducing the vertical permeability may lead to a reduced landfill gas emission to the atmosphere, and landfill gas would be accumulated inside the landfill. Finally, this method is simple and can allow for a greater number of measurements during a relatively shorter period. Thus, it provides a better representation of the significant space and time variations in methane emission fluxes. PMID:27401161

  2. Estimation of methane emission flux at landfill surface using laser methane detector: Influence of gauge pressure.

    PubMed

    Park, Jin-Kyu; Kang, Jong-Yun; Lee, Nam-Hoon

    2016-08-01

    The aim of this study was to investigate the possibility of measuring methane emission fluxes, using surface methane concentration and gauge pressure, by analyzing the influence of gauge pressure on the methane emission flux and the surface methane concentration, as well as the correlation between the methane emission flux and surface methane concentrations. The surface methane concentration was measured using a laser methane detector. Our results show a positive linear relationship between the surface methane concentration and the methane emission flux. Furthermore, the methane emission flux showed a positive linear relationship with the gauge pressure; this implies that when the surface methane concentration and the surface gauge pressure are measured simultaneously, the methane emission flux can be calculated using Darcy's law. A decrease in the vertical permeability was observed when the gauge pressure was increased, because reducing the vertical permeability may lead to a reduced landfill gas emission to the atmosphere, and landfill gas would be accumulated inside the landfill. Finally, this method is simple and can allow for a greater number of measurements during a relatively shorter period. Thus, it provides a better representation of the significant space and time variations in methane emission fluxes.

  3. Investigating ion-surface collisions with a niobium superconducting tunnel junction detector in a time-of-flight mass spectrometer

    SciTech Connect

    Westmacott, G.; Zhong, F.; Frank, M.; Friedrich, S.; Labov, S.; Benner, W.H.

    1999-12-01

    The performance of an energy sensitive, niobium superconducting tunnel junction detector is investigated by measuring the pulse height produced by impacting molecular and atomic ions at different kinetic energies. Ions are produced by laser resorption and matrix-assisted laser desorption in a time-of-flight mass spectrometer. Results show that the STJ detector pulse height decreases for increasing molecular ion mass, passes through a minimum at around 2000 Da, and the increases with increasing mass of molecular ions above 2000Da. The detector does not show a decline in sensitivity for high mass ions as is observed with microchannel plate ion detectors. These detector plus height measurements are discussed in terms of several physical mechanisms involved in an ion-surface collision.

  4. Haystack Observatory

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Radio astronomy programs comprise three very-long-baseline interferometer projects, ten spectral line investigations, one continuum mapping in the 0.8 cm region, and one monitoring of variable sources. A low-noise mixer was used in mapping observations of 3C273 at 31 GHz and in detecting of a new methyl alcohol line at 36,169 MHz in Sgr B2. The new Mark 2 VLBI recording terminal was used in galactic H2O source observations using Haystack and the Crimean Observatory, USSR. One feature in W29 appears to have a diameter of 0.3 millisec of arc and a brightness temperature of 1.4 x 10 to the 15th power K. Geodetic baseline measurements via VLBI between Green Bank and Haystack are mutually consistent within a few meters. Radar investigations of Mercury, Venus, Mars, and the Moon have continued. The favorable opposition of Mars and improvements in the radar permit measurements on a number of topographic features with unprecedented accuracy, including scarps and crater walls. The floor of Mare Serenitatis slopes upward towards the northeast and is also the location of a strong gravitational anomaly.

  5. Microwave detection of cosmic ray showers at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Facal, Pedro

    2012-03-01

    Microwave emission from the electromagnetic cascade induced in the atmosphere by ultra-high energy cosmic rays (UHECR) may allow for a novel detection technique, which combines the advantages of the well-established fluorescence technique - the reconstruction of the shower profile - with a 100% duty cycle, minimal atmospheric attenuation and the use of low-cost commercial equipment. Two complementary techniques are currently being pursued at the Pierre Auger Observatory. AMBER (Air-shower Microwave Bremsstrahlung Experimental Radiometer), MIDAS (Microwave Detection of Air Showers) and FDWave are prototypes for a large imaging dish antenna. In EASIER (Extensive Air Shower Identification using Electron Radiometer), the microwave emission is detected by antenna horns located on each surface detector of the Auger Observatory. MIDAS is a self-triggering system while AMBER, FDWave, and EASIER use the trigger from the Auger detectors to record the emission. The coincident detection of UHECR by the microwave prototype detectors and the fluorescence and surface detectors will prove the viability of this novel technique. The status of microwave R&D activities at the Pierre Auger Observatory will be reported.

  6. A compendium of results from long-range alpha detector soil surface monitoring: June 1992--May 1994

    SciTech Connect

    Garner, S.E.; Bounds, J.A.; Allander, K.S.; Johnson, J.D.; MacArthur, D.W.; Caress, R.W.

    1994-11-01

    Soil surface monitors based on long-range alpha detector (LRAD) technology are being used to monitor alpha contamination at various sites in the Department of Energy complex. These monitors, the large soil-surface monitor (LSSM) and the small soil-surface monitor (SSSM), were used to help characterize sites at Fernald, Ohio, and active or inactive firing sites at Sandia National Laboratories and Los Alamos National Laboratory. Monitoring results are presented herein in chronological order.

  7. Study of surface recombination on cleaved and passivated edges of Si detectors

    NASA Astrophysics Data System (ADS)

    Gaubas, E.; Ceponis, T.; Vaitkus, J. V.; Fadeyev, V.; Ely, S.; Galloway, Z.; F-W Sadrozinski, H.; Christophersen, M.; Phlips, B. F.; Gorelov, I.; Hoeferkamp, M.; Metcalfe, J.; Seidel, S.

    2016-03-01

    The effectiveness of the passivation of a cleaved boundary of large area strip detectors has been studied by using Al2O3 formed by atomic layer deposition technology for p-Si structures and Si x N y grown on n-Si by plasma enhanced chemical vapour deposition. The parameters of bulk and surface recombinations have been examined in a contactless mode implemented through analysis of the microwave-probed photoconductivity transients. Rather efficient and reproducible passivation, revealed through the reduction of surface recombination velocities from ˜2 × 104 to 5 × 103 cm s-1 for n-Si and from ˜2 × 104 to 3 × 102 cm s-1 for p-Si samples, has been obtained. The existence of trapping centres together with recombination defects has been revealed at the cleaved interface within the passivating layer. It has been revealed that the impact of surface recombination is negligible when bulk radiation defects are dominant in samples irradiated with fluences >1014 neq cm-2.

  8. The Sudbury Neutrino Observatory

    NASA Astrophysics Data System (ADS)

    Ewan, G. T.

    1992-04-01

    The Sudbury Neutrino Observatory (SNO) detector is a 1000 ton heavy water (D2O) Cherenkov detector designed to study neutrinos from the sun and other astrophysical sources. The use of heavy water allows both electron neutrinos and all other types of neutrinos to be observed by three complementary reactions. The detector will be sensitive to the electron neutrino flux and energy spectrum shape and to the total neutrino flux irrespective of neutrino type. These measurements will provide information on both vacuum neutrino oscillations and matter-enhanced oscillations, the MSW effect. In the event of a supernova it will be very sensitive to muon and tau neutrinos as well as the electron neutrinos emitted in the initial burst, enabling sensitive mass measurements as well as providing details of the physics of stellar collapse. On behalf of the Sudbury Neutrino Observatory (SNO) Collaboration : H.C . Evans, G.T . Ewan, H.W. Lee, J .R . Leslie, J .D. MacArthur, H .-B . Mak, A.B . McDonald, W. McLatchie, B.C . Robertson, B. Sur, P. Skensved (Queen's University) ; C.K . Hargrove, H. Mes, W.F. Davidson, D. Sinclair, 1 . Blevis, M. Shatkay (Centre for Research in Particle Physics) ; E.D. Earle, G.M. Milton, E. Bonvin, (Chalk River Laboratories); J .J . Simpson, P. Jagam, J . Law, J .-X . Wang (University of Guelph); E.D . Hallman, R.U. Haq (Laurentian University); A.L. Carter, D. Kessler, B.R . Hollebone (Carleton University); R. Schubank . C.E . Waltha m (University of British Columbia); R.T. Kouzes, M.M. Lowry, R.M. Key (Princeton University); E.W. Beier, W. Frati, M. Newcomer, R. Van Berg (University of Penn-sylvania), T.J . Bowles, P.J . Doe, S.R . Elliott, M.M. Fowler, R.G.H. Robertson, D.J . Vieira, J .B . Wilhelmy, J .F. Wilker-son, J .M. Wouters (Los Alamos National Laboratory) ; E. Norman, K. Lesko, A. Smith, R. Fulton, R. Stokstad (Lawrence Berkeley Laboratory), N.W. Tanner, N. JCIILY, P. Trent, J . Barton, D.L . Wark (University of Oxford).

  9. Structural and Electronic Properties of Gold Contacts on CdZnTe with Different Surface Finishes for Radiation Detector Applications

    NASA Astrophysics Data System (ADS)

    Tari, S.; Aqariden, F.; Chang, Y.; Ciani, A.; Grein, C.; Li, Jin; Kioussis, N.

    2014-08-01

    State-of-the-art room-temperature, high-resolution x-ray and gamma-ray semiconductor detectors can be fabricated from CdZnTe (CZT) crystals. The structural and electronic properties of the CZT surface, especially the contact interfaces, can have a substantial effect on radiation detector performance, for example leakage current, signal-to-noise ratio, and energy resolution, especially for soft x-rays and large pixilated arrays. Atomically smooth and defect-free surfaces are desirable for high-performance CZT-based detectors; chemo-mechanical polishing (CMP) is typically performed to produce such surfaces. The electrical behavior of the metal/CZT interface varies substantially with surface preparation before contact deposition, and with choice of metal and deposition technique. We report a systematic study of the structural and electronic properties of gold (Au) contacts on CZT prepared with different surface finishes. We observed subsurface damage under Au contacts on CMP-finished CZT and abrupt interfaces for Au on chemically-polished (CP) CZT. Schottky barrier formation was observed for Au contacts, irrespective of surface finish, and less charge trapping and low surface resistance were observed for CP-finished surfaces. Pre-deposition surface treatment produced interfaces free from oxide layers.

  10. Dynamic of the atmospheric boundary layer from the isotopic composition of surface water vapor at the Maïdo Observatory (La Réunion, Indian Ocean)

    NASA Astrophysics Data System (ADS)

    Guilpart, Etienne; Vimeux, Francoise; Metzger, Jean-Marc; Evan, Stephanie; Brioude, Jerome; Cattani, Olivier

    2016-04-01

    Projections of tropical and subtropical precipitation strongly differ from one climate model to another, both in sign and in amplitude. This is the case for example in some parts of the West Indian Ocean. The causes of those uncertainties are numerous and a better understanding of humid processes in the tropical atmosphere is needed. We propose to address this burning question by using water stables isotopes. We have been measuring the isotopic composition of surface water vapor at the atmospheric Observatory of Maïdo located at La Reunion Island (21°S, 55°E, 2200m a.s.l) since November 2014. Our results exhibit a strong diurnal cycle all over the year (except during cyclonic activity), with almost constant isotopic values during the day (around -13.5±0.6‰ for oxygen 18 from November 2014 to November 2015) and variable and very depleted isotopic values during the night (down to -35‰ for oxygen 18 over the same period) associated with low humidity levels. We will show in this presentation that the diurnal isotopic variations are associated to a strong air masses mixing. During the day, the isotopic composition of the vapor is typical of marine boundary layer (BL) moisture transported from the close Ocean and lifted up to the Maïdo station. During the night, the depleted values and the low humidity could trace free troposphere moisture, which is consistent with previous studies suggesting that the Maïdo Observatory is above the BL during the night. We will explore the influence of the daily BL development on our observations, using a set of atmospheric vertical profiles done on site in May 2015 during the BIOMAIDO campaign. At last, we will discuss the most isotopic depleted values recorded in our observations during the night as a possible consequence of regional strong subsidences.

  11. ESO's Two Observatories Merge

    NASA Astrophysics Data System (ADS)

    2005-02-01

    , a unique instrument capable of measuring stellar radial velocities with an unsurpassed accuracy better than 1 m/s, making it a very powerful tool for the discovery of extra-solar planets. In addition, astronomers have also access to the 2.2-m ESO/MPG telescope with its Wide Field Imager camera. A new control room, the RITZ (Remote Integrated Telescope Zentrum), allows operating all three ESO telescopes at La Silla from a single place. The La Silla Observatory is also the first world-class observatory to have been granted certification for the International Organization for Standardization (ISO) 9001 Quality Management System. Moreover, the infrastructure of La Silla is still used by many of the ESO member states for targeted projects such as the Swiss 1.2-m Euler telescope and the robotic telescope specialized in the follow-up of gamma-ray bursts detected by satellites, the Italian REM (Rapid Eye Mount). In addition, La Silla is in charge of the APEX (Atacama Pathfinder Experiment) 12-m sub-millimetre telescope which will soon start routine observations at Chajnantor, the site of the future Atacama Large Millimeter Array (ALMA). The APEX project is a collaboration between the Max Planck Society in Germany, Onsala Observatory in Sweden and ESO. ESO also operates Paranal, home of the Very Large Telescope (VLT) and the VLT Interferometer (VLTI). Antu, the first 8.2-m Unit Telescope of the VLT, saw First Light in May 1998, starting what has become a revolution in European astronomy. Since then, the three other Unit Telescopes - Kueyen, Melipal and Yepun - have been successfully put into operation with an impressive suite of the most advanced astronomical instruments. The interferometric mode of the VLT (VLTI) is also operational and fully integrated in the VLT data flow system. In the VLTI mode, one state-of-the-art instrument is already available and another will follow soon. With its remarkable resolution and unsurpassed surface area, the VLT is at the forefront of

  12. The studies of Schottky-diode based co-plane detector for surface plasmon resonance sensing

    NASA Astrophysics Data System (ADS)

    Liu, Chien-Sheng; Wen, Tsun-Yu; Wang, Da-Shin; Lin, Chii-Wann

    2010-08-01

    The Surface Plasmon Resonance (SPR) is a label-free, highly sensitive and real time sensing technique and has been extensively applied to biosensing and assay for decades. In a conventional SPR biosensor, a prism is used to create the total reflection in which the evanescent wave can excite the surface plasmon mode at the metal-dielectric interface at certain angle, at which condition the reflectivity of incident TM-polarized vanished as measured by a far-field photodetector. This is the optical detection of surface plasmon resonance. In this research, zinc oxide (ZnO) was used as the dielectric thin-film material above the gold surface on the glass substrate to form a co-plane Schottky diode; this structure is designed to be an alternative way to detect SPR. The strength of plasmonic field is possible to be monitored by measuring the photocurrent under the reverse bias. According to our experimental results, the measured photocurrents with TM-polarized illumination (representing the SPR case), TE-polarized illumination (non-SPR case) and no illumination conditions under DC -1.5V bias are -76.158mA (2.5μA), -76.085mA (3.6μA) and -76.089mA (3.4μA), respectively. Based on the results, we have demonstrated this Schottky diode based co-plane device has the potential to be used as the SPR detector and provides a possible solution for the need of a low-cost, miniaturized, electronically integrated, and portable SPR biosensor in the near future.

  13. Light-Sharing Interface for dMiCE Detectors Using Sub-Surface Laser Engraving

    PubMed Central

    Hunter, William C. J.; Miyaoka, Robert S.; MacDonald, Lawrence; McDougald, Wendy; Lewellen, Thomas K.

    2015-01-01

    We have previously reported on dMiCE, a method of resolving depth or interaction (DOI) in a pair of discrete crystals by encoding light sharing properties as a function of depth in the interface of a crystal-element pair. A challenge for this method is the cost and repeatability of interface treatment for each crystal pair. In this work, we report our preliminary results on using sub-surface laser engraving (SSLE) as a means of forming this depth-dependent interface in a dMiCE detector. A surplus first-generation SSLE system was used to create a partially reflective layer 100-microns thick at the boundary between two halves of a 1.4-by-2.9-by-20 mm3 LYSO crystal. The boundary of these paired crystal elements was positioned between two 3-mm wide Silicon photomultiplier arrays. The responses of these two photodetectors were acquired for an ensemble of 511-keV photons collimated to interact at a fixed depth in just one crystal element. Interaction position was then varied to measure detector response as a function of depth, which was then used to maximum-likelihood positions. Despite use of sub-optimal SSLE processing we found an average DOI resolution of 3.4 mm for front-sided readout and 3.9 mm for back-sided readout while obtaining energy resolutions on the order of 10%. We expect DOI resolution can be improved significantly by optimizing the SSLE process and pattern. PMID:25914421

  14. Sudbury Neutrino Observatory

    SciTech Connect

    Beier, E.W.

    1992-03-01

    This document is a technical progress report on work performed at the University of Pennsylvania during the current year on the Sudbury Neutrino Observatory project. The motivation for the experiment is the measurement of neutrinos emitted by the sun. The Sudbury Neutrino Observatory (SNO) is a second generation dedicated solar neutrino experiment which will extend the results of our work with the Kamiokande II detector by measuring three reactions of neutrinos rather than the single reaction measured by the Kamiokande experiment. The collaborative project includes physicists from Canada, the United Kingdom, and the United States. Full funding for the construction of this facility was obtained in January 1990, and its construction is estimated to take five years. The motivation for the SNO experiment is to study the fundamental properties of neutrinos, in particular the mass and mixing parameters, which remain undetermined after decades of experiments in neutrino physics utilizing accelerators and reactors as sources of neutrinos. To continue the study of neutrino properties it is necessary to use the sun as a neutrino source. The long distance to the sun makes the search for neutrino mass sensitive to much smaller mass than can be studied with terrestrial sources. Furthermore, the matter density in the sun is sufficiently large to enhance the effects of small mixing between electron neutrinos and mu or tau neutrinos. This experiment, when combined with the results of the radiochemical {sup 37}Cl and {sup 71}Ga experiments and the Kamiokande II experiment, should extend our knowledge of these fundamental particles, and as a byproduct, improve our understanding of energy generation in the sun.

  15. Measurement of the Muon Production Depths at the Pierre Auger Observatory

    DOE PAGES

    Collica, Laura

    2016-09-08

    The muon content of extensive air showers is an observable sensitive to the primary composition and to the hadronic interaction properties. The Pierre Auger Observatory uses water-Cherenkov detectors to measure particle densities at the ground and therefore is sensitive to the muon content of air showers. We present here a method which allows us to estimate the muon production depths by exploiting the measurement of the muon arrival times at the ground recorded with the Surface Detector of the Pierre Auger Observatory. The analysis is performed in a large range of zenith angles, thanks to the capability of estimating and subtracting the electromagnetic component, and for energies betweenmore » $$10^{19.2}$$ and $$10^{20}$$ eV.« less

  16. Measurement of the muon production depths at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Collica, Laura

    2016-09-01

    The muon content of extensive air showers is an observable sensitive to the primary composition and to the hadronic interaction properties. The Pierre Auger Observatory uses water-Cherenkov detectors to measure particle densities at the ground and therefore is sensitive to the muon content of air showers. We present here a method which allows us to estimate the muon production depths by exploiting the measurement of the muon arrival times at the ground recorded with the Surface Detector of the Pierre Auger Observatory. The analysis is performed in a large range of zenith angles, thanks to the capability of estimating and subtracting the electromagnetic component, and for energies between 1019.2 and 1020eV.

  17. Portable coastal observatories

    USGS Publications Warehouse

    Frye, Daniel; Butman, Bradford; Johnson, Mark; von der Heydt, Keith; Lerner, Steven

    2000-01-01

    Ocean observational science is in the midst of a paradigm shift from an expeditionary science centered on short research cruises and deployments of internally recording instruments to a sustained observational science where the ocean is monitored on a regular basis, much the way the atmosphere is monitored. While satellite remote sensing is one key way of meeting the challenge of real-time monitoring of large ocean regions, new technologies are required for in situ observations to measure conditions below the ocean surface and to measure ocean characteristics not observable from space. One method of making sustained observations in the coastal ocean is to install a fiber optic cable from shore to the area of interest. This approach has the advantage of providing power to offshore instruments and essentially unlimited bandwidth for data. The LEO-15 observatory offshore of New Jersey (yon Alt et al., 1997) and the planned Katama observatory offshore of Martha's Vineyard (Edson et al., 2000) use this approach. These sites, along with other cabled sites, will play an important role in coastal ocean science in the next decade. Cabled observatories, however, have two drawbacks that limit the number of sites that are likely to be installed. First, the cable and the cable installation are expensive and the shore station needed at the cable terminus is often in an environmentally sensitive area where competing interests must be resolved. Second, cabled sites are inherently limited geographically to sites within reach of the cable, so it is difficult to cover large areas of the coastal ocean.

  18. Systematic study of atmosphere-induced influences and uncertainties on shower reconstruction at the Pierre Auger Observatory

    SciTech Connect

    Prouza, Michael; Collaboration, for the Pierre Auger

    2007-06-01

    A wide range of atmospheric monitoring instruments is employed at the Pierre Auger Observatory : two laser facilities, elastic lidar stations, aerosol phase function monitors, a horizontal attenuation monitor, star monitors, weather stations, and balloon soundings. We describe the impact of analyzed atmospheric data on the accuracy of shower reconstructions, and in particular study the effect of the data on the shower energy and the depth of shower maximum (X{sub max}). These effects have been studied using the subset of 'golden hybrid' events--events observed with high quality in the fluorescence and surface detector -- used in the calibration of the surface detector energy spectrum.

  19. Golden legacy from ESA's observatory

    NASA Astrophysics Data System (ADS)

    2003-07-01

    ISO was the first space observatory able to see the sky in infrared light. Using its eyes, we have discovered many new phenomena that have radically changed our view of the Universe. Everybody knows that when something is heated it glows. However, things also glow with a light our eyes cannot detect at room temperature: infrared light. Infrared telescopes do not work well on the Earth’s surface because such light is absorbed by the atmosphere. ISO looked at the cold parts of the universe, usually the 'cold and dusty' parts. It peered into clouds of dust and gas where stars were being born, observing for the first time the earliest stages of star formation. It discovered, for example, that stars begin to form at temperatures as low as -250°C or less. Scientists were able to follow the evolution of dust from where it is produced (that is, old stars - the massive 'dust factories') to the regions where it forms new planetary systems. ISO found that most young stars are surrounded by discs of dust that could harbour planets. The observatory also analysed the chemical composition of cosmic dust, thereby opening up a new field of research, ‘astromineralogy’. With ISO we have been able to discover the presence of water in many different regions in space. Another new discipline, 'astrochemistry', was boosted when ISO discovered that the water molecule is common in the Universe, even in distant galaxies, and complex organic molecules like benzene readily form in the surroundings of some stars. "ISO results are impacting most fields of astronomical research, almost literally from comets to cosmology," explains Alberto Salama, ISO Project Scientist. "Some results answer questions. Others open new fields. Some are already being followed up by existing telescopes; others have to await future facilities." When ISO's operational life ended, in 1998, its observations became freely available to the world scientific community via ISO’s data archive. In May 2003 the

  20. NASA's Great Observatories Paper Model Kits.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC. Education Dept.

    The Hubble Space Telescope, the most complex and sensitive optical telescope ever made, was built to study the cosmos from low-Earth orbit for 10 to 15 years or more. The Compton Gamma Ray Observatory is a complex spacecraft fitted with four different gamma ray detectors, each of which concentrates on different but overlapping energy range and was…

  1. Novel Surface Preparation and Contacts for CdZnTe Nuclear Radiation Detectors Using Patterned Films of Semiconductors and Insulators

    NASA Astrophysics Data System (ADS)

    Burger, Arnold; Groza, Michael; Conway, Adam; Payne, Steve

    2013-04-01

    The semiconductor Cadmium Zinc Telluride (CZT) has emerged as the material of choice for room temperature detection of X-rays and gamma-rays. The detectors will cover the energy range from 30 keV to several MeV, and will achieve excellent 662 keV energy resolution. The development of high resolution gamma ray detectors based on CZT is dependent on low electronic noise levels. One common source of noise is the surface leakage current, which limits the performance of advanced readout schemes such as the coplanar grid and pixelated architectures with steering grids. Excessive bulk leakage current can result from one of several surface effects: leaky native oxides, unsatisfied bonds, and surface damage. We propose to fabricate and test oriented [111] CZT crystals with thicknesses up to 1.5 cm with an innovative detection technique based on co-planar or other electron only transport designs using plasma processing, thin film sputtering, chemical passivation and wet etching techniques. Compared to conventional pixel detectors, the proposed contact configuration needs lower power consumption and a lower cost. The detector design can be used for building very low-cost handheld radiation detection devices.

  2. Charge management for gravitational-wave observatories using UV LEDs

    SciTech Connect

    Pollack, S. E.; Turner, M. D.; Schlamminger, S.; Hagedorn, C. A.; Gundlach, J. H.

    2010-01-15

    Accumulation of electrical charge on the end mirrors of gravitational-wave observatories can become a source of noise limiting the sensitivity of such detectors through electronic couplings to nearby surfaces. Torsion balances provide an ideal means for testing gravitational-wave technologies due to their high sensitivity to small forces. Our torsion pendulum apparatus consists of a movable plate brought near a plate pendulum suspended from a nonconducting quartz fiber. A UV LED located near the pendulum photoejects electrons from the surface, and a UV LED driven electron gun directs photoelectrons towards the pendulum surface. We have demonstrated both charging and discharging of the pendulum with equivalent charging rates of {approx}10{sup 5}e/s, as well as spectral measurements of the pendulum charge resulting in a white noise level equivalent to 3x10{sup 5}e/{radical}(Hz).

  3. Charge management for gravitational-wave observatories using UV LEDs

    NASA Astrophysics Data System (ADS)

    Pollack, S. E.; Turner, M. D.; Schlamminger, S.; Hagedorn, C. A.; Gundlach, J. H.

    2010-01-01

    Accumulation of electrical charge on the end mirrors of gravitational-wave observatories can become a source of noise limiting the sensitivity of such detectors through electronic couplings to nearby surfaces. Torsion balances provide an ideal means for testing gravitational-wave technologies due to their high sensitivity to small forces. Our torsion pendulum apparatus consists of a movable plate brought near a plate pendulum suspended from a nonconducting quartz fiber. A UV LED located near the pendulum photoejects electrons from the surface, and a UV LED driven electron gun directs photoelectrons towards the pendulum surface. We have demonstrated both charging and discharging of the pendulum with equivalent charging rates of ˜105e/s, as well as spectral measurements of the pendulum charge resulting in a white noise level equivalent to 3×105e/Hz.

  4. HAWC: The high altitude water Cherenkov observatory

    NASA Astrophysics Data System (ADS)

    Goodman, Jordan A.

    2013-02-01

    The High Altitude Water Cherenkov Observatory (HAWC) is currently being deployed at 4100m above sea level on the Vulcan Sierra Negra near Puebla, Mexico. The HAWC observatory will consist of 250-300 Water Cherenkov Detectors totaling approximately 22,000 m2 of instrumented area. The water Cherenkov technique allows HAWC to have a nearly 100% duty cycle and large field of view, making the HAWC observatory an ideal instrument for the study of transient phenomena. With its large effective area, excellent angular and energy resolutions, and efficient gamma-hadron separation, HAWC will survey the TeV gamma-ray sky, measure spectra of galactic sources from 1 TeV to beyond 100 TeV, and map galactic diffuse gamma ray emission. The science goals, instrument performance and status of the HAWC observatory will be presented.

  5. The Boulder magnetic observatory

    USGS Publications Warehouse

    Love, Jeffrey J.; Finn, Carol A.; Pedrie, Kolby L.; Blum, Cletus C.

    2015-08-14

    The Boulder magnetic observatory has, since 1963, been operated by the Geomagnetism Program of the U.S. Geological Survey in accordance with Bureau and national priorities. Data from the observatory are used for a wide variety of scientific purposes, both pure and applied. The observatory also supports developmental projects within the Geomagnetism Program and collaborative projects with allied geophysical agencies.

  6. the Large Aperture GRB Observatory

    SciTech Connect

    Bertou, Xavier

    2009-04-30

    The Large Aperture GRB Observatory (LAGO) aims at the detection of high energy photons from Gamma Ray Bursts (GRB) using the single particle technique (SPT) in ground based water Cherenkov detectors (WCD). To reach a reasonable sensitivity, high altitude mountain sites have been selected in Mexico (Sierra Negra, 4550 m a.s.l.), Bolivia (Chacaltaya, 5300 m a.s.l.) and Venezuela (Merida, 4765 m a.s.l.). We report on the project progresses and the first operation at high altitude, search for bursts in 6 months of preliminary data, as well as search for signal at ground level when satellites report a burst.

  7. Seismic surface-wave dispersion profiling versus shear-wave refraction tomography on a granite-micaschists contact at Plœmeur hydrological observatory (France)

    NASA Astrophysics Data System (ADS)

    Pasquet, S.; Bodet, L.; Dhemaied, A.; Guérin, R.; Longuevergne, L.; Faycal, R.

    2013-12-01

    Despite well-known generation and detection issues, shear (S-) wave-related techniques grow in popularity with the increase of multicomponent data acquisitions in hydrocarbon exploration. In the meantime, recent studies demonstrated that pressure (P-) wave reflection, P-wave refraction and surface-wave dispersion data could be simultaneously acquired and analyzed for the characterization of the investigated medium. Retrieving 2D P-wave velocity (Vp) and S-wave velocity (Vs) sections with a single standard acquisition setup appears promising and attractive in terms of time and equipment costs, more particularly in the context of near-surface applications (at depth lower than 100 m). The literature even shows recent attempts of using Vp/Vs ratio to estimate hydrological parameters of aquifer systems. But refraction tomography and surface-wave dispersion inversion obviously involve distinct characteristics of the wavefield and different assumptions about the medium. The methods consequently provide results of different resolutions and investigation depths. We addressed these issues thanks to a seismic survey conducted on a well-known granite-micaschists contact at Plœmeur hydrological observatory (France). We performed simultaneous P-wave refraction tomography and surface-wave profiling, along with SH-wave refraction tomography, on a line intersecting the contact zone. The combined interpretation of Vp and Vs sections retrieved from refraction tomography helps defining the lateral extent of the contact zone, when only one section is insufficient. As for surface-wave profiling, we used offset moving windows and dispersion stacking techniques to extract a collection of local dispersion measurements along the line. We then inverted each dispersion curve separately and reconstructed a pseudo-2D Vs section along the profile. Three different window sizes were tested. They provide sections evidently different in terms of lateral resolution and investigation depth. To select

  8. ESO's Two Observatories Merge

    NASA Astrophysics Data System (ADS)

    2005-02-01

    , a unique instrument capable of measuring stellar radial velocities with an unsurpassed accuracy better than 1 m/s, making it a very powerful tool for the discovery of extra-solar planets. In addition, astronomers have also access to the 2.2-m ESO/MPG telescope with its Wide Field Imager camera. A new control room, the RITZ (Remote Integrated Telescope Zentrum), allows operating all three ESO telescopes at La Silla from a single place. The La Silla Observatory is also the first world-class observatory to have been granted certification for the International Organization for Standardization (ISO) 9001 Quality Management System. Moreover, the infrastructure of La Silla is still used by many of the ESO member states for targeted projects such as the Swiss 1.2-m Euler telescope and the robotic telescope specialized in the follow-up of gamma-ray bursts detected by satellites, the Italian REM (Rapid Eye Mount). In addition, La Silla is in charge of the APEX (Atacama Pathfinder Experiment) 12-m sub-millimetre telescope which will soon start routine observations at Chajnantor, the site of the future Atacama Large Millimeter Array (ALMA). The APEX project is a collaboration between the Max Planck Society in Germany, Onsala Observatory in Sweden and ESO. ESO also operates Paranal, home of the Very Large Telescope (VLT) and the VLT Interferometer (VLTI). Antu, the first 8.2-m Unit Telescope of the VLT, saw First Light in May 1998, starting what has become a revolution in European astronomy. Since then, the three other Unit Telescopes - Kueyen, Melipal and Yepun - have been successfully put into operation with an impressive suite of the most advanced astronomical instruments. The interferometric mode of the VLT (VLTI) is also operational and fully integrated in the VLT data flow system. In the VLTI mode, one state-of-the-art instrument is already available and another will follow soon. With its remarkable resolution and unsurpassed surface area, the VLT is at the forefront of

  9. Ultrahigh Energy Neutrinos at the Pierre Auger Observatory

    DOE PAGES

    Abreu, P.; Aglietta, M.; Ahlers, M.; Ahn, E. J.; Albuquerque, I. F. M.; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Almela, A.; et al

    2013-01-01

    The observation of ultrahigh energy neutrinos (UHE ν s) has become a priority in experimental astroparticle physics. UHE ν s can be detected with a variety of techniques. In particular, neutrinos can interact in the atmosphere (downward-going ν ) or in the Earth crust (Earth-skimming ν ), producing air showers that can be observed with arrays of detectors at the ground. With the surface detector array of the Pierre Auger Observatory we can detect these types of cascades. The distinguishing signature for neutrino events is the presence of very inclined showers produced close to the ground (i.e., after havingmore » traversed a large amount of atmosphere). In this work we review the procedure and criteria established to search for UHE ν s in the data collected with the ground array of the Pierre Auger Observatory. This includes Earth-skimming as well as downward-going neutrinos. No neutrino candidates have been found, which allows us to place competitive limits to the diffuse flux of UHE ν s in the EeV range and above.« less

  10. Preliminary investigation of KTN as a surface acoustic wave infrared/thermal detector

    SciTech Connect

    Korsah, Kofi

    2005-01-01

    This paper presents the results of preliminary investigations of thin films of KTN (KTa1−xNbxO3) surface acoustic wave (SAW) structures for their suitability as thermal detectors. The goal is to use the technique for infrared (IR) detection and imaging. The thin films (0.6 m) of K(Ta1−xNbx)O3 [x = 0.5] epitaxial films were grown and polished on KTaO3 (0 0 1) substrates approximately 1 mm thick. SAW resonators with a center frequency of approximately 480 MHz were fabricated using these substrates. To form the basis of comparison to commonly used, thermally sensitive SAW substrates, SAW devices using lithium niobate (LiNbO3) as the substrate material were also fabricated. The phase response as a function of temperature for the KTN as well as the LiNbO3 SAW devices was measured with a network analyzer. The largest phase change exhibited by the LiNbO3 was about −4.7 / C, whereas the largest phase change exhibited by the KTN was about twice as much (11 / C). Assuming a worst case network analyzer phase resolution of 0.5 , this corresponds to a temperature resolution of 0.1 C for the LiNbO3 and 0.05 C for the KTN. By comparison, typical sensitivity of (uncooled) microbolometers is of the order of 50 mK. We believe that with improved fabrication and signal processing, the KTN/SAW-based detection approach can achieve a temperature resolution of better than 50 mK.

  11. X-RAY PHOTOEMISSION ANALYSIS OF PASSIVATED Cd(1-x)ZnxTe SURFACES FOR IMPROVED RADIATION DETECTORS

    SciTech Connect

    Nelson, A; Conway, A; Reinhardt, C; Ferreira, J; Nikolic, R; Payne, S

    2008-05-12

    Surface passivation of device-grade CdZnTe was investigated using x-ray photoelectron spectroscopy in combination with transport property measurements after Br-MeOH (2% Br) and KOH/NH{sub 4}F/H{sub 2}O{sub 2} solutions were used to etch and oxidize the surface. High-resolution photoemission measurements on the valence band electronic structure and core lines were used to evaluate the surface chemistry of the chemically treated surfaces. Metal overlayers were then deposited on these chemically treated surfaces and the I-V characteristics measured. The measurements were correlated to understand the effect of interface chemistry on the electronic structure at these interfaces with the goal of optimizing the Schottky barrier height for radiation detector devices.

  12. Compton Gamma-Ray Observatory

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This photograph shows the Compton Gamma-Ray Observatory being released from the Remote Manipulator System (RMS) arm aboard the Space Shuttle Atlantis during the STS-35 mission in April 1991. The GRO reentered the Earth's atmosphere and ended its successful mission in June 2000. For nearly 9 years, GRO's Burst and Transient Source Experiment (BATSE), designed and built by the Marshall Space Flight Center, kept an unblinking watch on the universe to alert scientist to the invisible, mysterious gamma-ray bursts that had puzzled them for decades. By studying gamma-rays from objects like black holes, pulsars, quasars, neutron stars, and other exotic objects, scientists could discover clues to the birth, evolution, and death of star, galaxies, and the universe. The gamma-ray instrument was one of four major science instruments aboard the Compton. It consisted of eight detectors, or modules, located at each corner of the rectangular satellite to simultaneously scan the entire universe for bursts of gamma-rays ranging in duration from fractions of a second to minutes. In January 1999, the instrument, via the Internet, cued a computer-controlled telescope at Las Alamos National Laboratory in Los Alamos, New Mexico, within 20 seconds of registering a burst. With this capability, the gamma-ray experiment came to serve as a gamma-ray burst alert for the Hubble Space Telescope, the Chandra X-Ray Observatory, and major gound-based observatories around the world. Thirty-seven universities, observatories, and NASA centers in 19 states, and 11 more institutions in Europe and Russia, participated in BATSE's science program.

  13. Compton Gamma-Ray Observatory

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This photograph shows the Compton Gamma-Ray Observatory (GRO) being deployed by the Remote Manipulator System (RMS) arm aboard the Space Shuttle Atlantis during the STS-37 mission in April 1991. The GRO reentered Earth atmosphere and ended its successful mission in June 2000. For nearly 9 years, the GRO Burst and Transient Source Experiment (BATSE), designed and built by the Marshall Space Flight Center (MSFC), kept an unblinking watch on the universe to alert scientists to the invisible, mysterious gamma-ray bursts that had puzzled them for decades. By studying gamma-rays from objects like black holes, pulsars, quasars, neutron stars, and other exotic objects, scientists could discover clues to the birth, evolution, and death of stars, galaxies, and the universe. The gamma-ray instrument was one of four major science instruments aboard the Compton. It consisted of eight detectors, or modules, located at each corner of the rectangular satellite to simultaneously scan the entire universe for bursts of gamma-rays ranging in duration from fractions of a second to minutes. In January 1999, the instrument, via the Internet, cued a computer-controlled telescope at Las Alamos National Laboratory in Los Alamos, New Mexico, within 20 seconds of registering a burst. With this capability, the gamma-ray experiment came to serve as a gamma-ray burst alert for the Hubble Space Telescope, the Chandra X-Ray Observatory, and major gound-based observatories around the world. Thirty-seven universities, observatories, and NASA centers in 19 states, and 11 more institutions in Europe and Russia, participated in the BATSE science program.

  14. A dark-matter search using the final CDMS II dataset and a novel detector of surface radiocontamination

    SciTech Connect

    Ahmed, Zeeshan

    2012-01-01

    Substantial evidence from galaxies, galaxy clusters, and cosmological scales suggests that ~85% of the matter of our universe is invisible. The missing matter, or "dark matter" is likely composed of non-relativistic, non-baryonic particles, which have very rare interactions with baryonic matter and with one another. Among dark matter candidates, Weakly Interacting Massive Particles (WIMPs) are particularly well motivated. In the early universe, thermally produced particles with weak-scale mass and interactions would `freeze out’ at the correct density to be dark matter today. Extensions to the Standard Model of particle physics, such as Supersymmetry, which solve gauge hierarchy and coupling unification problems, naturally provide such particles. Interactions of WIMPs with baryons are expected to be rare, but might be detectable in low-noise detectors. The Cryogenic Dark Matter Search (CDMS) experiment uses ionization- and phonon- sensitive germanium particle detectors to search for such interactions. CDMS detectors are operated at the Soudan Underground Laboratory in Minnesota, within a shielded environment to lower cosmogenic and radioactive background. The combination of phonon and ionization signatures from the detectors provides excellent residual-background rejection. This dissertation presents improved techniques for phonon calibration of CDMS II detectors and the analysis of the final CDMS II dataset with 612 kg-days of exposure. We set a limit of 3.8x10$^{-}$44 cm$^{2}$ on WIMP-nucleon spin-independent scattering cross section for a WIMP mass of 70 GeV/c$^{2}$. At the time this analysis was published, these data presented the most stringent limits on WIMP scattering for WIMP masses over 42 GeV/c$^{2}$, ruling out previously unexplored parameter space. Next-generation rare-event searches such as SuperCDMS, COUPP, and CLEAN will be limited in sensitivity, unless they achieve stringent control of the surface radioactive contamination on their detectors. Low

  15. Combining Surface Treatments with Shallow Slots to Improve the Spatial Resolution Performance of Continuous, Thick LYSO Detectors for PET.

    PubMed

    Kaul, M; Surti, S; Karp, J S

    2013-02-01

    Positron emission tomography (PET) detectors based on continuous scintillation crystals can achieve very good performance and have a number of practical advantages compared to detectors based on a pixelated array of crystals. Our goal is to develop a thick continuous detector with high energy and spatial resolution, along with high γ-photon capture efficiency. We examine the performance of two crystal blocks: a 46 × 46 × 14 mm(3) and a 48 × 48 × 25 mm(3) block of LYSO (Lutetium Yttrium Orthosilicate). Using Maximum Likelihood (ML) positioning based upon the light response function (LRF) in the 14 mm thick crystal, we measure a spatial resolution of 3 mm in the central region of the crystal with degradation near the edges due to reflections off the crystal sides. We also show that we can match the spatial resolution achieved using a 14 mm thick crystal by using a 25 mm thick crystal with slots cut into the gamma entrance surface to narrow the LRF. We also find that we can improve the spatial resolution performance near the detector edges by reducing the reflectivity of the crystal sides, albeit with some loss in energy resolution. PMID:24077642

  16. ISRU-based development of a lunar water astroparticle observatory

    NASA Astrophysics Data System (ADS)

    Ignatiev, Alex; Heiss, Klaus; van Susante, Paul

    2007-06-01

    Lunar Water Astroparticle Observatories are proposed to be fabricated at the Lunar North and South Poles by use of Lunar in situ resources. These observatories will consist, initially, of a 10m×10m×10m basin excavated, to be filled with 1000 metric tons of water from the in situ resources at the Polar Regions. The water basin would be constructed by excavation of a cavity out of the regolith, lined with waterproof material and then filled with water extracted from the adjacent permanently dark crater regions. These permanently dark regions are believed to contain water (ice) at a 1 5% concentration level. This water would be extracted by microwave heating of the regolith, the evolved water vapor and other gases then captured, followed by condensation of the water vapor. The microwave heating would be done with a suspended source rastered over the ice field in a crater. The condensed water would be transported to the detector basins, would fill the basins, which would then be sealed to prevent evaporation to the Moon's environment. The energy for the construction of the cavity detectors and the water extraction would come from solar cell arrays fabricated on the surface of the Moon on crater rims to receive maximum sunlight, and integrated into an electric power system that would supply energy for the microwave melting of the ice, for the motive power for the cavity excavation and, later, for the operation of the detection and measurement systems deployed in and around the water observatory and the processing and the transmission of the data to Earth.

  17. The Little Thompson Observatory

    NASA Astrophysics Data System (ADS)

    Schweitzer, A.; Melsheimer, T.; Rideout, C.; Vanlew, K.

    1998-12-01

    The Little Thompson Observatory is believed to be the first observatory built as part of a high school and accessible to other schools remotely, via the Internet. This observatory is the second member of the Telescopes in Education (TIE) project. Construction is nearly completed and first light is planned for fall 1998. The observatory is located on the grounds of Berthoud High School in northern Colorado. Local schools and youth organizations will have prioritized access to the telescope, and there will also be opportunities for public viewing. After midnight, the telescope will be open to world-wide use by schools via the Internet following the model of the first TIE observatory, the 24" telescope on Mt. Wilson. That telescope has been in use for the past four years by up to 50 schools per month. Students remotely connect to the observatory over the Internet, and then receive the images on their local computers. The observatory grew out of grassroots support from the local community surrounding Berthoud, Colorado, a town of 3,500 residents. TIE has provided the observatory with a Tinsley 18" Cassegrain telescope on a 10-year loan. The facility has been built with tremendous support from volunteers and the local school district. We have applied for an IDEAS grant to provide teacher training workshops which will allow K-12 schools in northern Colorado to make use of the Little Thompson Observatory, including remote observing from classrooms.

  18. The Little Thompson Observatory

    NASA Astrophysics Data System (ADS)

    Schweitzer, A.; Melsheimer, T.; Sackett, C.

    1999-05-01

    The Little Thompson Observatory is believed to be the first observatory built as part of a high school and accessible to other schools remotely, via the Internet. This observatory is the second member of the Telescopes in Education (TIE) project. Construction of the building and dome has been completed, and first light is planned for spring 1999. The observatory is located on the grounds of Berthoud High School in northern Colorado. Local schools and youth organizations will have prioritized access to the telescope, and there will also be opportunities for public viewing. After midnight, the telescope will be open to world-wide use by schools via the Internet following the model of the first TIE observatory, the 24" telescope on Mt. Wilson. Students remotely connect to the observatory over the Internet, and then receive the images on their local computers. The observatory grew out of grassroots support from the local community surrounding Berthoud, Colorado, a town of 3,500 residents. TIE has provided the observatory with a Tinsley 18" Cassegrain telescope on a 10-year loan. The facility has been built with tremendous support from volunteers and the local school district. We have received an IDEAS grant to provide teacher training workshops which will allow K-12 schools in northern Colorado to make use of the Little Thompson Observatory, including remote observing from classrooms.

  19. The Pierre Auger Observatory scaler mode for the study of solar activity modulation of galactic cosmic rays

    NASA Astrophysics Data System (ADS)

    Pierre Auger Collaboration; Abreu, P.; Aglietta, M.; Ahn, E. J.; Allard, D.; Allekotte, I.; Allen, J.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Antičić, T.; Anzalone, A.; Aramo, C.; Arganda, E.; Arisaka, K.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Bäcker, T.; Badagnani, D.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Beatty, J. J.; Becker, B. R.; Becker, K. H.; Bellétoile, A.; Bellido, J. A.; BenZvi, S.; Berat, C.; Bergmann, T.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Blümer, H.; Boháčová, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brogueira, P.; Brown, W. C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Burton, R. E.; Busca, N. G.; Caballero-Mora, K. S.; Caramete, L.; Caruso, R.; Castellina, A.; Catalano, O.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Chiavassa, A.; Chinellato, J. A.; Chou, A.; Chudoba, J.; Clay, R. W.; Colombo, E.; Coluccia, M. R.; Conceição, R.; Contreras, F.; Cook, H.; Cooper, M. J.; Coppens, J.; Cordier, A.; Cotti, U.; Coutu, S.; Covault, C. E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; De Domenico, M.; De Donato, C.; de Jong, S. J.; De La Vega, G.; de Mello Junior, W. J. M.; de Mello Neto, J. R. T.; De Mitri, I.; de Souza, V.; de Vries, K. D.; Decerprit, G.; del Peral, L.; Deligny, O.; Della Selva, A.; Dembinski, H.; Denkiewicz, A.; Di Giulio, C.; Diaz, J. C.; Díaz Castro, M. L.; Diep, P. N.; Dobrigkeit, C.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; dos Anjos, J. C.; Dova, M. T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C. O.; Etchegoyen, A.; Facal San Luis, P.; Falcke, H.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Ferrero, A.; Fick, B.; Filevich, A.; Filipčič, A.; Fleck, I.; Fliescher, S.; Fracchiolla, C. E.; Fraenkel, E. D.; Fröhlich, U.; Fuchs, B.; Fulgione, W.; Gamarra, R. F.; Gambetta, S.; García, B.; García Gámez, D.; Garcia-Pinto, D.; Garrido, X.; Gascon, A.; Gelmini, G.; Gemmeke, H.; Gesterling, K.; Ghia, P. L.; Giaccari, U.; Giller, M.; Glass, H.; Gold, M. S.; Golup, G.; Gomez Albarracin, F.; Gómez Berisso, M.; Gonçalves, P.; Gonzalez, D.; Gonzalez, J. G.; Gookin, B.; Góra, D.; Gorgi, A.; Gouffon, P.; Gozzini, S. R.; Grashorn, E.; Grebe, S.; Grigat, M.; Grillo, A. F.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Hague, J. D.; Hansen, P.; Harari, D.; Harmsma, S.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A. E.; Hojvat, C.; Holmes, V. C.; Homola, P.; Hórandel, J. R.; Horneffer, A.; Hrabovský, M.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jiraskova, S.; Kadija, K.; Kaducak, M.; Kampert, K. H.; Karhan, P.; Karova, T.; Kasper, P.; Kégl, B.; Keilhauer, B.; Keivani, A.; Kelley, J. L.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D.-H.; Kotera, K.; Krohm, N.; Krömer, O.; Kruppke-Hansen, D.; Kuehn, F.; Kuempel, D.; Kulbartz, J. K.; Kunka, N.; La Rosa, G.; Lachaud, C.; Lautridou, P.; Leão, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Lemiere, A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; López, R.; Lopez Agüera, A.; Louedec, K.; Lozano Bahilo, J.; Lucero, A.; Ludwig, M.; Lyberis, H.; Maccarone, M. C.; Macolino, C.; Maldera, S.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, V.; Maris, I. C.; Marquez Falcon, H. R.; Marsella, G.; Martello, D.; Martin, L.; Martínez Bravo, O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mazur, P. O.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Meurer, C.; Mičanović, S.; Micheletti, M. I.; Miller, W.; Miramonti, L.; Mollerach, S.; Monasor, M.; Monnier Ragaigne, D.; Montanet, F.; Morales, B.; Morello, C.; Moreno, E.; Moreno, J. C.; Morris, C.; Mostafá, M.; Mueller, S.; Muller, M. A.; Müller, G.; Münchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J. L.; Navas, S.; Necesal, P.; Nellen, L.; Nhung, P. T.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nožka, L.; Nyklicek, M.; Oehlschläger, J.; Olinto, A.; Oliva, P.; Olmos-Gilbaja, V. M.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Parrisius, J.; Parsons, R. D.; Pastor, S.; Paul, T.; Pavlidou c, V.; Payet, K.; Pech, M.; Pękala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrinca, P.; Petrolini, A.; Petrov, Y.; Petrovic, J.; Pfendner, C.; Phan, N.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.; Platino, M.; Ponce, V. H.; Pontz, M.; Privitera, P.; Prouza, M.; Quel, E. J.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Revenu, B.; Ridky, J.; Riggi, S.; Risse, M.; Ristori, P.; Rivera, H.; Rivière, C.; Rizi, V.; Robledo, C.; Rodriguez, G.; Rodriguez Martino, J.; Rodriguez Rojo, J.; Rodriguez-Cabo, I.; Rodríguez-Frías, M. D.; Ros, G.; Rosado, J.; Rossler, T.; Roth, M.; Rouillé-d'Orfeuil, B.; Roulet, E.; Rovero, A. C.; Salamida, F.; Salazar, H.; Salina, G.; Sánchez, F.; Santander, M.; Santo, C. E.; Santos, E.; Santos, E. M.; Sarazin, F.; Sarkar, S.; Sato, R.; Scharf, N.; Scherini, V.; Schieler, H.; Schiffer, P.; Schmidt, A.; Schmidt, F.; Schmidt, T.; Scholten, O.; Schoorlemmer, H.; Schovancova, J.; Schovánek, P.; Schroeder, F.; Schulte, S.; Schüssler, F.; Schuster, D.; Sciutto, S. J.; Scuderi, M.; Segreto, A.; Semikoz, D.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sidelnik, I.; Sigl, G.; Śmiałkowski, A.; Šmída, R.; Snow, G. R.; Sommers, P.; Sorokin, J.; Spinka, H.; Squartini, R.; Stapleton, J.; Stasielak, J.; Stephan, M.; Strazzeri, E.; Stutz, A.; Suarez, F.; Suomijärvi, T.; Supanitsky, A. D.; Šuša, T.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Tamashiro, A.; Tapia, A.; Tarutina, T.; Taşcǎu, O.; Tcaciuc, R.; Tcherniakhovski, D.; Tegolo, D.; Thao, N. T.; Thomas, D.; Tiffenberg, J.; Timmermans, C.; Tiwari, D. K.; Tkaczyk, W.; Todero Peixoto, C. J.; Tomé, B.; Tonachini, A.; Travnicek, P.; Tridapalli, D. B.; Tristram, G.; Trovato, E.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van den Berg, A. M.; Vargas Cárdenas, B.; Vázquez, J. R.; Vázquez, R. A.; Veberič, D.; Venters, T.; Verzi, V.; Videla, M.; Villaseñor, L.; Wahlberg, H.; Wahrlich, P.; Wainberg, O.; Warner, D.; Watson, A. A.; Weber, M.; Weidenhaupt, K.; Weindl, A.; Westerhoff, S.; Whelan, B. J.; Wieczorek, G.; Wiencke, L.; Wilczyńska, B.; Wilczyński, H.; Will, M.; Williams, C.; Winchen, T.; Winders, L.; Winnick, M. G.; Wommer, M.; Wundheiler, B.; Yamamoto a, T.; Younk, P.; Yuan, G.; Yushkov, A.; Zamorano, B.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zaw, I.; Zepeda, A.; Ziolkowski, M.

    2011-01-01

    Since data-taking began in January 2004, the Pierre Auger Observatory has been recording the count rates of low energy secondary cosmic ray particles for the self-calibration of the ground detectors of its surface detector array. After correcting for atmospheric effects, modulations of galactic cosmic rays due to solar activity and transient events are observed. Temporal variations related with the activity of the heliosphere can be determined with high accuracy due to the high total count rates. In this study, the available data are presented together with an analysis focused on the observation of Forbush decreases, where a strong correlation with neutron monitor data is found.

  20. Detection of cosmic rays using microwave radiation at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    San Luis, P. Facal; Pierre Auger Collaboration

    2013-05-01

    Radiation in the microwave band has been measured in coincidence with the passage of a particle beam through a dedicated chamber. This radiation could provide a new technique for the study of ultra high energy cosmic rays, its main advantages being the possibility to instrument a large area with a detector sensitive to the mass compostion of cosmic rays, 100% duty cycle, virtually no atmospheric attenuation and the use of relatively cheap equipment. Cosmic ray detection in the GHz band is being actively pursued at the Pierre Auger Observatory with three different set-ups: MIDAS and AMBER are prototypes of an imaging radio-detector based on a parabolic dish reflector, while EASIER instruments the surface detector stations with a radio system of wide angular coverage. The status of microwave R&D activities at Auger, including the first event detected by EASIER, is reported.

  1. The Norwegian Naval Observatories

    NASA Astrophysics Data System (ADS)

    Pettersen, Bjørn Ragnvald

    2007-07-01

    Archival material has revealed milestones and new details in the history of the Norwegian Naval Observatories. We have identified several of the instrument types used at different epochs. Observational results have been extracted from handwritten sources and an extensive literature search. These allow determination of an approximate location of the first naval observatory building (1842) at Fredriksvern. No physical remains exist today. A second observatory was established in 1854 at the new main naval base at Horten. Its location is evident on military maps and photographs. We describe its development until the Naval Observatory buildings, including archives and instruments, were completely demolished during an allied air bomb raid on 23 February 1945. The first director, C.T.H. Geelmuyden, maintained scientific standards at the the Observatory between 1842 and 1870, and collaborated with university astronomers to investigate, develop, and employ time-transfer by telegraphy. Their purpose was accurate longitude determination between observatories in Norway and abroad. The Naval Observatory issued telegraphic time signals twice weekly to a national network of sites, and as such served as the first national time-service in Norway. Later the Naval Observatory focused on the particular needs of the Navy and developed into an internal navigational service.

  2. INTERMAGNET and magnetic observatories

    USGS Publications Warehouse

    Love, Jeffrey J.; Chulliat, Arnaud

    2012-01-01

    A magnetic observatory is a specially designed ground-based facility that supports time-series measurement of the Earth’s magnetic field. Observatory data record a superposition of time-dependent signals related to a fantastic diversity of physical processes in the Earth’s core, mantle, lithosphere, ocean, ionosphere, magnetosphere, and, even, the Sun and solar wind.

  3. Zelenchukskaya Radio Astronomical Observatory

    NASA Technical Reports Server (NTRS)

    Smolentsev, Sergey; Dyakov, Andrei

    2013-01-01

    This report summarizes information about Zelenchukskaya Radio Astronomical Observatory activities in 2012. Last year a number of changes took place in the observatory to improve some technical characteristics and to upgrade some units to the required status. The report provides an overview of current geodetic VLBI activities and gives an outlook for the future.

  4. Svetloe Radio Astronomical Observatory

    NASA Technical Reports Server (NTRS)

    Smolentsev, Sergey; Rahimov, Ismail

    2013-01-01

    This report summarizes information about the Svetloe Radio Astronomical Observatory activities in 2012. Last year, a number of changes took place in the observatory to improve some technical characteristics and to upgrade some units to their required status. The report provides an overview of current geodetic VLBI activities and gives an outlook for the future.

  5. Einstein Observatory (HEAO-2)

    NASA Astrophysics Data System (ADS)

    Bond, P.; Murdin, P.

    2002-04-01

    The second in the series of HIGH ENERGY ASTROPHYSICAL OBSERVATORIES was launched by an Atlas-Centaur rocket on 13 November 1978. Soon after its insertion into a 470 km circular orbit inclined at 23.5° to the equator, HEAO-2 was named the Einstein Observatory, in celebration of the centenary of Albert Einstein's birth....

  6. The Space Telescope Observatory

    NASA Technical Reports Server (NTRS)

    Bahcall, J. N.; Odell, C. R.

    1979-01-01

    A convenient guide to the expected characteristics of the Space Telescope Observatory for astronomers and physicists is presented. An attempt is made to provide enough detail so that a professional scientist, observer or theorist, can plan how the observatory may be used to further his observing programs or to test theoretical models.

  7. Strasbourg's "Academy" observatory

    NASA Astrophysics Data System (ADS)

    Heck, André

    2011-08-01

    The observing post located on the roof of Strasbourg's 19th-century "Academy" is generally considered as the second astronomical observatory of the city: a transitional facility between the (unproductive) turret lantern at the top of the Hospital Gate and the German (Wilhelminian) Observatory. The current paper reviews recent findings from archives (blueprints, inventories, correspondence, decrees and other documents) shedding some light on this observatory of which virtually nothing was known to this day. While being, thanks to Chrétien Kramp (1760-1826), an effective attempt to establish an actual observatory equipped with genuine instrumentation, the succession of political regimes in France and the continual bidding for moving the university to other locations, together with the faltering of later scholars, torpedoed any significant scientific usage of the place. A meridian instrument with a Cauchoix objective doublet was however recovered by the German observatory and is still existing.

  8. India-based Neutrino Observatory(INO): A Status Report

    SciTech Connect

    Murthy, M. V. N.

    2011-11-23

    We present a status report on the proposed India-based Neutrino Observatory (INO). Various aspects of the INO project such as its location, the present status of the detector development, physics goals and simulation studies are discussed briefly. In particular we focus on physics studies possible with an iron calorimeter detector (ICAL) and the logistics of constructing this detector at INO. Such a detector would make precision measurements of neutrino oscillation parameters with atmospheric neutrinos in the first phase with the possibility of acting as a far-end detector of a future neutrino factory or beta beam.

  9. An upper limit to the photon fraction in cosmic rays above 10**19-eV from the Pierre Auger Observatory

    SciTech Connect

    Abraham, J.; Aglietta, M.; Aguirre, C.; Allard, D.; Allekotte, I.; Allison, P.; Alvarez, C.; Alvarez-Muniz, J.; Ambrosio, M.; Anchordoqui, L.; Anjos, J.C.; /Centro Atomico Bariloche /Buenos Aires, CONICET /La Plata U. /Pierre Auger Observ. /CNEA, San Martin /Adelaide U. /Catholic U. of Bolivia, La Paz /Bolivia U. /Sao Paulo U. /Campinas State U. /UEFS, Feira de Santana

    2006-06-01

    An upper limit of 16% (at 95% c.l.) is derived for the photon fraction in cosmic rays with energies above 10{sup 19} eV, based on observations of the depth of shower maximum performed with the hybrid detector of the Pierre Auger Observatory. This is the first such limit on photons obtained by observing the fluorescence light profile of air showers. This upper limit confirms and improves on previous results from the Haverah Park and AGASA surface arrays. Additional data recorded with the Auger surface detectors for a subset of the event sample, support the conclusion that a photon origin of the observed events is not favored.

  10. Particle Physics with the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Pierog, T.

    2014-06-01

    The Pierre Auger Observatory is the world largest extensive air shower detector. Based on two detection techniques, namely fluorescence telescopes for the observation of the longitudinal development and water Cherenkov detectors for particles at ground, this experiment can be used not only as a cosmic ray observatory, but also to study the basic properties of hadronic interactions leading the development of air showers initiated by these primary cosmic rays. We will show that by using careful data selection it is possible to extract the proton-air inelastic cross-section at energies much higher than that accessible at man-made accelerators. Taking advantage of both detection techniques we will demonstrate that it is also possible to test hadronic interaction models using correlations between different air shower observables, like shower maximum and muons at ground, to reduce the uncertainty due to the unknown beam of cosmic rays.

  11. 4th generation of the 1st level surface detector trigger in the Pierre Auger Observator

    NASA Astrophysics Data System (ADS)

    Szadkowski, Z.

    The proposal of a new 4th generation of the Front-End with the advanced 1st level triggers for the Infill Array of the Pierre Auger Observatory and for the Auger North is described. Newest FPGA chips offer much higher capacity of logic registers and memories, as well as DSP blocks. The calibration channel, previously supported by an external dual-port RAM, has been fully implemented into FPGA chip, through a large internal memory. In turn DSP blocks allowed on implementation of much more sophisticated spectral trigger algorithms. A single chip simplified board design, newer architecture of FPGA reduced resouces utilization and power consumption. Higher sampling in the new Front- End in comparison with previous 40 MHz designs as well as free resources for new detection algotithms can be a good platform for CR radio detection technique at Auger enhancing a duty cycle for the detection of UHECR’s.

  12. Evading surface and detector frequency noise in harmonic oscillator measurements of force gradients

    NASA Astrophysics Data System (ADS)

    Moore, Eric W.; Lee, SangGap; Hickman, Steven A.; Harrell, Lee E.; Marohn, John A.

    2010-07-01

    We introduce and demonstrate a method of measuring small force gradients acting on a harmonic oscillator in which the force-gradient signal of interest is used to parametrically up-convert a forced oscillation below resonance into an amplitude signal at the oscillator's resonance frequency. The approach, which we demonstrate in a mechanically detected electron spin resonance experiment, allows the force-gradient signal to evade detector frequency noise by converting a slowly modulated frequency signal into an amplitude signal.

  13. Measurement of the proton-air cross section with Telescope Array's Middle Drum detector and surface array in hybrid mode

    NASA Astrophysics Data System (ADS)

    Abbasi, R. U.; Abe, M.; Abu-Zayyad, T.; Allen, M.; Azuma, R.; Barcikowski, E.; Belz, J. W.; Bergman, D. R.; Blake, S. A.; Cady, R.; Chae, M. J.; Cheon, B. G.; Chiba, J.; Chikawa, M.; Cho, W. R.; Fujii, T.; Fukushima, M.; Goto, T.; Hanlon, W.; Hayashi, Y.; Hayashida, N.; Hibino, K.; Honda, K.; Ikeda, D.; Inoue, N.; Ishii, T.; Ishimori, R.; Ito, H.; Ivanov, D.; Jui, C. C. H.; Kadota, K.; Kakimoto, F.; Kalashev, O.; Kasahara, K.; Kawai, H.; Kawakami, S.; Kawana, S.; Kawata, K.; Kido, E.; Kim, H. B.; Kim, J. H.; Kim, J. H.; Kitamura, S.; Kitamura, Y.; Kuzmin, V.; Kwon, Y. J.; Lan, J.; Lim, S. I.; Lundquist, J. P.; Machida, K.; Martens, K.; Matsuda, T.; Matsuyama, T.; Matthews, J. N.; Minamino, M.; Mukai, Y.; Myers, I.; Nagasawa, K.; Nagataki, S.; Nakamura, T.; Nonaka, T.; Nozato, A.; Ogio, S.; Ogura, J.; Ohnishi, M.; Ohoka, H.; Oki, K.; Okuda, T.; Ono, M.; Oshima, A.; Ozawa, S.; Park, I. H.; Pshirkov, M. S.; Rodriguez, D. C.; Rubtsov, G.; Ryu, D.; Sagawa, H.; Sakurai, N.; Scott, L. M.; Shah, P. D.; Shibata, F.; Shibata, T.; Shimodaira, H.; Shin, B. K.; Shin, H. S.; Smith, J. D.; Sokolsky, P.; Springer, R. W.; Stokes, B. T.; Stratton, S. R.; Stroman, T. A.; Suzawa, T.; Takamura, M.; Takeda, M.; Takeishi, R.; Taketa, A.; Takita, M.; Tameda, Y.; Tanaka, H.; Tanaka, K.; Tanaka, M.; Thomas, S. B.; Thomson, G. B.; Tinyakov, P.; Tkachev, I.; Tokuno, H.; Tomida, T.; Troitsky, S.; Tsunesada, Y.; Tsutsumi, K.; Uchihori, Y.; Udo, S.; Urban, F.; Vasiloff, G.; Wong, T.; Yamane, R.; Yamaoka, H.; Yamazaki, K.; Yang, J.; Yashiro, K.; Yoneda, Y.; Yoshida, S.; Yoshii, H.; Zollinger, R.; Zundel, Z.; Telescope Array Collaboration

    2015-08-01

    In this work we are reporting on the measurement of the proton-air inelastic cross section σp-air inel using the Telescope Array detector. Based on the measurement of the σp-air inel, the proton-proton cross section σp -p value is also determined at √{s }=9 5-8+5 TeV . Detecting cosmic ray events at ultrahigh energies with the Telescope Array enables us to study this fundamental parameter that we are otherwise unable to access with particle accelerators. The data used in this report are the hybrid events observed by the Middle Drum fluorescence detector together with the surface array detector collected over five years. The value of the σp-air inel is found to be equal to 567.0 ±70.5 [Stat]-25+29[Sys] mb . The total proton-proton cross section is subsequently inferred from Glauber formalism and the Block, Halzen and Stanev QCD inspired fit and is found to be equal to 17 0-44+48[Stat]-17+19[Sys] mb .

  14. The Little Thompson Observatory

    NASA Astrophysics Data System (ADS)

    Schweitzer, A. E.; VanLew, K.; Melsheimer, T.; Sackett, C.

    1999-12-01

    The Little Thompson Observatory is the second member of the Telescopes in Education (TIE) project. Construction of the dome and the remote control system has been completed, and the telescope is now on-line and operational over the Internet. The observatory is located on the grounds of Berthoud High School in northern Colorado. Local schools and youth organizations have prioritized access to the telescope, and there are monthly opportunities for public viewing. In the future, the telescope will be open after midnight to world-wide use by schools following the model of the first TIE observatory, the 24" telescope on Mt. Wilson. Students remotely connect to the observatory over the Internet, and then receive the images on their local computers. The observatory grew out of grassroots support from the local community surrounding Berthoud, Colorado, a town of 3,500 residents. TIE has provided the observatory with a Tinsley 18" Cassegrain telescope on a 10-year loan. The facility has been built with tremendous support from volunteers and the local school district. With funding from an IDEAS grant, we have begun teacher training workshops which will allow K-12 schools in northern Colorado to make use of the Little Thompson Observatory, including remote observing from classrooms.

  15. The Virtual Observatory: I

    NASA Astrophysics Data System (ADS)

    Hanisch, R. J.

    2014-11-01

    The concept of the Virtual Observatory arose more-or-less simultaneously in the United States and Europe circa 2000. Ten pages of Astronomy and Astrophysics in the New Millennium: Panel Reports (National Academy Press, Washington, 2001), that is, the detailed recommendations of the Panel on Theory, Computation, and Data Exploration of the 2000 Decadal Survey in Astronomy, are dedicated to describing the motivation for, scientific value of, and major components required in implementing the National Virtual Observatory. European initiatives included the Astrophysical Virtual Observatory at the European Southern Observatory, the AstroGrid project in the United Kingdom, and the Euro-VO (sponsored by the European Union). Organizational/conceptual meetings were held in the US at the California Institute of Technology (Virtual Observatories of the Future, June 13-16, 2000) and at ESO Headquarters in Garching, Germany (Mining the Sky, July 31-August 4, 2000; Toward an International Virtual Observatory, June 10-14, 2002). The nascent US, UK, and European VO projects formed the International Virtual Observatory Alliance (IVOA) at the June 2002 meeting in Garching, with yours truly as the first chair. The IVOA has grown to a membership of twenty-one national projects and programs on six continents, and has developed a broad suite of data access protocols and standards that have been widely implemented. Astronomers can now discover, access, and compare data from hundreds of telescopes and facilities, hosted at hundreds of organizations worldwide, stored in thousands of databases, all with a single query.

  16. Study of Ultra-High Energy Cosmic Ray composition using Telescope Array's Middle Drum detector and surface array in hybrid mode

    NASA Astrophysics Data System (ADS)

    Abbasi, R. U.; Abe, M.; Abu-Zayyad, T.; Allen, M.; Anderson, R.; Azuma, R.; Barcikowski, E.; Belz, J. W.; Bergman, D. R.; Blake, S. A.; Cady, R.; Chae, M. J.; Cheon, B. G.; Chiba, J.; Chikawa, M.; Cho, W. R.; Fujii, T.; Fukushima, M.; Goto, T.; Hanlon, W.; Hayashi, Y.; Hayashida, N.; Hibino, K.; Honda, K.; Ikeda, D.; Inoue, N.; Ishii, T.; Ishimori, R.; Ito, H.; Ivanov, D.; Jui, C. C. H.; Kadota, K.; Kakimoto, F.; Kalashev, O.; Kasahara, K.; Kawai, H.; Kawakami, S.; Kawana, S.; Kawata, K.; Kido, E.; Kim, H. B.; Kim, J. H.; Kim, J. H.; Kitamura, S.; Kitamura, Y.; Kuzmin, V.; Kwon, Y. J.; Lan, J.; Lim, S. I.; Lundquist, J. P.; Machida, K.; Martens, K.; Matsuda, T.; Matsuyama, T.; Matthews, J. N.; Minamino, M.; Mukai, Y.; Myers, I.; Nagasawa, K.; Nagataki, S.; Nakamura, T.; Nonaka, T.; Nozato, A.; Ogio, S.; Ogura, J.; Ohnishi, M.; Ohoka, H.; Oki, K.; Okuda, T.; Ono, M.; Oshima, A.; Ozawa, S.; Park, I. H.; Pshirkov, M. S.; Rodriguez, D. C.; Rubtsov, G.; Ryu, D.; Sagawa, H.; Sakurai, N.; Sampson, A. L.; Scott, L. M.; Shah, P. D.; Shibata, F.; Shibata, T.; Shimodaira, H.; Shin, B. K.; Shin, H. S.; Smith, J. D.; Sokolsky, P.; Springer, R. W.; Stokes, B. T.; Stratton, S. R.; Stroman, T.; Suzawa, T.; Takamura, M.; Takeda, M.; Takeishi, R.; Taketa, A.; Takita, M.; Tameda, Y.; Tanaka, H.; Tanaka, K.; Tanaka, M.; Thomas, S. B.; Thomson, G. B.; Tinyakov, P.; Tkachev, I.; Tokuno, H.; Tomida, T.; Troitsky, S.; Tsunesada, Y.; Tsutsumi, K.; Uchihori, Y.; Udo, S.; Urban, F.; Vasiloff, G.; Wong, T.; Yamane, R.; Yamaoka, H.; Yamazaki, K.; Yang, J.; Yashiro, K.; Yoneda, Y.; Yoshida, S.; Yoshii, H.; Zollinger, R.; Zundel, Z.

    2015-04-01

    Previous measurements of the composition of Ultra-High Energy Cosmic Rays (UHECRs) made by the High Resolution Fly's Eye (HiRes) and Pierre Auger Observatory (PAO) are seemingly contradictory, but utilize different detection methods, as HiRes was a stereo detector and PAO is a hybrid detector. The five year Telescope Array (TA) Middle Drum hybrid composition measurement is similar in some, but not all, respects in methodology to PAO, and good agreement is evident between data and a light, largely protonic, composition when comparing the measurements to predictions obtained with the QGSJetII-03 and QGSJet-01c models. These models are also in agreement with previous HiRes stereo measurements, confirming the equivalence of the stereo and hybrid methods. The data is incompatible with a pure iron composition, for all models examined, over the available range of energies. The elongation rate and mean values of Xmax are in good agreement with Pierre Auger Observatory data. This analysis is presented using two methods: data cuts using simple geometrical variables and a new pattern recognition technique.

  17. Manastash Ridge Observatory Autoguider Upgrade

    NASA Astrophysics Data System (ADS)

    Lozo, Jason; Huehnerhoff, Joseph; Armstrong, John; Davila, Adrian; Johnson, Courtney; McMaster, Alex; Olinger, Kyle

    2016-06-01

    The Astronomy Undergraduate Engineering Group (AUEG) at the University of Washington has designed and manufactured a novel autoguider system for the 0.8-meter telescope at the Manastash Ridge Observatory in Ellensburg, Washington. The system uses a pickoff mirror placed in the unused optical path, directing the outer field to the guide camera via a system of axi-symmetrically rotating relay mirrors (periscope). This allows the guider to sample nearly 7 times the area that would be possible with the same fixed detector. This system adds closed loop optical feedback to the tracking capabilities of the telescope. When tuned the telescope will be capable of acheiving 0.5 arcsecond tracking or better. Dynamic focusing of the primary optical path will also be an included feature of this system. This unique guider will be a much needed upgrade to the telescope allowing for increased scientific capability.

  18. Muons in air showers at the Pierre Auger Observatory: Measurement of atmospheric production depth

    NASA Astrophysics Data System (ADS)

    Aab, A.; Abreu, P.; Aglietta, M.; Ahlers, M.; Ahn, E. J.; Al Samarai, I.; Albuquerque, I. F. M.; Allekotte, I.; Allen, J.; Allison, P.; Almela, A.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Alves Batista, R.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Aramo, C.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Badescu, A. M.; Barber, K. B.; Bäuml, J.; Baus, C.; Beatty, J. J.; Becker, K. H.; Bellido, J. A.; Berat, C.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Blümer, H.; Boháčová, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brancus, I.; Brogueira, P.; Brown, W. C.; Buchholz, P.; Bueno, A.; Buscemi, M.; Caballero-Mora, K. S.; Caccianiga, B.; Caccianiga, L.; Candusso, M.; Caramete, L.; Caruso, R.; Castellina, A.; Cataldi, G.; Cazon, L.; Cester, R.; Chavez, A. G.; Cheng, S. H.; Chiavassa, A.; Chinellato, J. A.; Chudoba, J.; Cilmo, M.; Clay, R. W.; Cocciolo, G.; Colalillo, R.; Collica, L.; Coluccia, M. R.; Conceição, R.; Contreras, F.; Cooper, M. J.; Coutu, S.; Covault, C. E.; Criss, A.; Cronin, J.; Curutiu, A.; Dallier, R.; Daniel, B.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; De Domenico, M.; de Jong, S. J.; de Mello Neto, J. R. T.; De Mitri, I.; de Oliveira, J.; de Souza, V.; del Peral, L.; Deligny, O.; Dembinski, H.; Dhital, N.; Di Giulio, C.; Di Matteo, A.; Diaz, J. C.; Díaz Castro, M. L.; Diep, P. N.; Diogo, F.; Dobrigkeit, C.; Docters, W.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; Dorosti Hasankiadeh, Q.; Dova, M. T.; Ebr, J.; Engel, R.; Erdmann, M.; Erfani, M.; Escobar, C. O.; Espadanal, J.; Etchegoyen, A.; Facal San Luis, P.; Falcke, H.; Fang, K.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Fernandes, M.; Fick, B.; Figueira, J. M.; Filevich, A.; Filipčič, A.; Fox, B. D.; Fratu, O.; Fröhlich, U.; Fuchs, B.; Fuji, T.; Gaior, R.; García, B.; Garcia Roca, S. T.; Garcia-Gamez, D.; Garcia-Pinto, D.; Garilli, G.; Gascon Bravo, A.; Gate, F.; Gemmeke, H.; Ghia, P. L.; Giaccari, U.; Giammarchi, M.; Giller, M.; Glaser, C.; Glass, H.; Gomez Albarracin, F.; Gómez Berisso, M.; Gómez Vitale, P. F.; Gonçalves, P.; Gonzalez, J. G.; Gookin, B.; Gorgi, A.; Gorham, P.; Gouffon, P.; Grebe, S.; Griffith, N.; Grillo, A. F.; Grubb, T. D.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Hansen, P.; Harari, D.; Harrison, T. A.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Heimann, P.; Herve, A. E.; Hill, G. C.; Hojvat, C.; Hollon, N.; Holt, E.; Homola, P.; Hörandel, J. R.; Horvath, P.; Hrabovský, M.; Huber, D.; Huege, T.; Insolia, A.; Isar, P. G.; Islo, K.; Jandt, I.; Jansen, S.; Jarne, C.; Josebachuili, M.; Kääpä, A.; Kambeitz, O.; Kampert, K. H.; Kasper, P.; Katkov, I.; Kégl, B.; Keilhauer, B.; Keivani, A.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Krause, R.; Krohm, N.; Krömer, O.; Kruppke-Hansen, D.; Kuempel, D.; Kunka, N.; La Rosa, G.; LaHurd, D.; Latronico, L.; Lauer, R.; Lauscher, M.; Lautridou, P.; Le Coz, S.; Leão, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; López, R.; Lopez Agüera, A.; Louedec, K.; Lozano Bahilo, J.; Lu, L.; Lucero, A.; Ludwig, M.; Lyberis, H.; Maccarone, M. C.; Malacari, M.; Maldera, S.; Maller, J.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, V.; Mariş, I. C.; Marsella, G.; Martello, D.; Martin, L.; Martinez, H.; Martínez Bravo, O.; Martraire, D.; Masías Meza, J. J.; Mathes, H. J.; Mathys, S.; Matthews, A. J.; Matthews, J.; Matthiae, G.; Maurel, D.; Maurizio, D.; Mayotte, E.; Mazur, P. O.; Medina, C.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Messina, S.; Meyhandan, R.; Mićanović, S.; Micheletti, M. I.; Middendorf, L.; Minaya, I. A.; Miramonti, L.; Mitrica, B.; Molina-Bueno, L.; Mollerach, S.; Monasor, M.; Monnier Ragaigne, D.; Montanet, F.; Morello, C.; Moreno, J. C.; Mostafá, M.; Moura, C. A.; Muller, M. A.; Müller, G.; Münchmeyer, M.; Mussa, R.; Navarra, G.; Navas, S.; Necesal, P.; Nellen, L.; Nelles, A.; Neuser, J.; Niechciol, M.; Niemietz, L.; Niggemann, T.; Nitz, D.; Nosek, D.; Novotny, V.; Nožka, L.; Ochilo, L.; Olinto, A.; Oliveira, M.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Papenbreer, P.; Parente, G.; Parra, A.; Pastor, S.; Paul, T.; Pech, M.; PÈ©kala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Peters, C.; Petrera, S.; Petrolini, A.; Petrov, Y.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.; Platino, M.; Plum, M.; Porcelli, A.; Porowski, C.; Prado, R. R.; Privitera, P.; Prouza, M.; Purrello, V.; Quel, E. J.; Querchfeld, S.; Quinn, S.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Revenu, B.; Ridky, J.; Riggi, S.; Risse, M.; Ristori, P.; Rizi, V.; Roberts, J.; Rodrigues de Carvalho, W.; Rodriguez Cabo, I.; Rodriguez Fernandez, G.; Rodriguez Rojo, J.; Rodríguez-Frías, M. D.; Ros, G.; Rosado, J.; Rossler, T.; Roth, M.; Roulet, E.; Rovero, A. C.; Rühle, C.; Saffi, S. J.; Saftoiu, A.; Salamida, F.; Salazar, H.; Saleh, A.; Salesa Greus, F.; Salina, G.; Sánchez, F.; Sanchez-Lucas, P.; Santo, C. E.; Santos, E.; Santos, E. M.; Sarazin, F.; Sarkar, B.; Sarmento, R.; Sato, R.; Scharf, N.; Scherini, V.; Schieler, H.; Schiffer, P.; Schmidt, A.; Scholten, O.; Schoorlemmer, H.; Schovánek, P.; Schulz, A.; Schulz, J.; Sciutto, S. J.; Segreto, A.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sidelnik, I.; Sigl, G.; Sima, O.; Śmiałkowski, A.; Šmída, R.; Snow, G. R.; Sommers, P.; Sorokin, J.; Squartini, R.; Srivastava, Y. N.; Stanič, S.; Stapleton, J.; Stasielak, J.; Stephan, M.; Stutz, A.; Suarez, F.; Suomijärvi, T.; Supanitsky, A. D.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Szuba, M.; Taborda, O. A.; Tapia, A.; Tartare, M.; Thao, N. T.; Theodoro, V. M.; Tiffenberg, J.; Timmermans, C.; Todero Peixoto, C. J.; Toma, G.; Tomankova, L.; Tomé, B.; Tonachini, A.; Torralba Elipe, G.; Torres Machado, D.; Travnicek, P.; Trovato, E.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van Aar, G.; van den Berg, A. M.; van Velzen, S.; van Vliet, A.; Varela, E.; Vargas Cárdenas, B.; Varner, G.; Vázquez, J. R.; Vázquez, R. A.; Veberič, D.; Verzi, V.; Vicha, J.; Videla, M.; Villaseñor, L.; Vlcek, B.; Vorobiov, S.; Wahlberg, H.; Wainberg, O.; Walz, D.; Watson, A. A.; Weber, M.; Weidenhaupt, K.; Weindl, A.; Werner, F.; Whelan, B. J.; Widom, A.; Wiencke, L.; Wilczyńska, B.; Wilczyński, H.; Will, M.; Williams, C.; Winchen, T.; Wittkowski, D.; Wundheiler, B.; Wykes, S.; Yamamoto, T.; Yapici, T.; Younk, P.; Yuan, G.; Yushkov, A.; Zamorano, B.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zaw, I.; Zepeda, A.; Zhou, J.; Zhu, Y.; Zimbres Silva, M.; Ziolkowski, M.; Pierre Auger Collaboration

    2014-07-01

    The surface detector array of the Pierre Auger Observatory provides information about the longitudinal development of the muonic component of extensive air showers. Using the timing information from the flash analog-to-digital converter traces of surface detectors far from the shower core, it is possible to reconstruct a muon production depth distribution. We characterize the goodness of this reconstruction for zenith angles around 60° and different energies of the primary particle. From these distributions, we define Xmaxμ as the depth along the shower axis where the production of muons reaches maximum. We explore the potentiality of Xmaxμ as a useful observable to infer the mass composition of ultrahigh-energy cosmic rays. Likewise, we assess its ability to constrain hadronic interaction models.

  19. Radio detection of extensive air showers at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Berat, C.

    2013-08-01

    The Pierre Auger Observatory explores the potential of radio-detection techniques to measure extensive air showers (EAS) induced by ultra-high energy cosmic rays. To study in detail the mechanisms responsible for radio emission in the MHz range, the Auger Engineering Radio Array has been installed at the Observatory. Presently consisting of 24 radio-detection stations, this number will grow to 150 units covering an area of almost 20 km2. Novel detection techniques based on the GHz emission from the EAS are currently being studied. AMBER (Air-shower Microwave Bremsstrahlung Experimental Radiometer) and MIDAS (Microwave Detection of Air Showers) are prototypes for a large imaging dish antenna. In EASIER (Extensive Air Shower Identification using Electron Radiometer), the microwave emission is detected by antenna horns located on each surface detector. MIDAS is a self-triggering system while AMBER and EASIER use the trigger from the Auger detectors to record the emission. The status of these radio-detection R&D efforts at the Pierre Auger Observatory will be reported.

  20. The High-Altitude Water Cherenkov Observatory: First Light

    NASA Astrophysics Data System (ADS)

    Weisgarber, Thomas

    2013-04-01

    The High-Altitude Water Cherenkov (HAWC) Observatory is under construction at Sierra Negra in the state of Puebla in Mexico. Operation began in September 2012, with the first 30 out of the final 300 water Cherenkov detectors deployed and in data acquisition. The HAWC Observatory is designed to record particle air showers from gamma rays and cosmic rays with TeV energies. Though the detector is only 10% complete, HAWC is already the world's largest water Cherenkov detector in the TeV band. In this presentation, I will summarize the performance of the detector to date and discuss preliminary observations of cosmic-ray and gamma-ray sources. I will also describe deployment plans for the remainder of the detector and outline prospects for TeV observations in the coming year.

  1. FPGA based triggers in the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Szadkowski, Z.

    2008-01-01

    The Pierre Auger Observatory is an international project for research on ultra-high energy cosmic rays (UHECR) above 10 19 eV and currently the world largest "hybrid" experiment. The hybrid technique uses both the detection of particles at the ground in water Cherenkov detectors (WCD) and measurements of fluorescence light generated in the atmosphere by the extensive air showers. This technique offers unique possibilities for cross-calibration and reduction of measurement uncertainties. The surface array will contain 1600 surface detector stations distributed over 3000 km2 in the Southern Hemisphere (under construction in Argentina) and 4000 WCD distributed over 10000 km2 at a Northern Hemisphere site in Colorado (deployment planned for 2008). Four fluorescence stations each containing 6 wide-angle Schmidt telescopes and each equipped with 440 PMTs with 1.5° angle resolution and 30 • 30° of field of view are located on the border of the surface array in the Southern Site. The paper presents implementations of the FPGA used for triggering. The use is illustrated with currently working schemes as well as other possible ideas especially promising for the surface detector in which currently used triggers seems to be not effective enough for very inclined and horizontal showers. Proposed new triggers enlarge a simple 1-bit threshold detection to the online analysis of a FADC trace shape. This corresponds to a charge from PMTs or signal power estimation. The next category is spectral triggers analyzing sequential samples in the frequency domain. Digital sigma-delta filters immunize the trigger circuitry on the pedestal variation as results of huge temperature swings. Presented DCT trigger provides native pedestal independence.

  2. Prototype optical SETI observatory

    NASA Astrophysics Data System (ADS)

    Kingsley, Stuart A.

    1996-06-01

    The Optical Search for Extraterrestrial Intelligence (OSETI) is based on the premise that there are ETIs within our galaxy which are targeting star systems like our own with free-space beams. Upon these beams will ride attention- getting beacon signals and wideband data channels. Perhaps the wideband channels form part of a Galactic Information Superhighway, a Galactic Internet to which we are presently oblivious. The Columbus Optical SETI Observatory described in this paper is intended to be a prototype observatory which might lead to a new renaissance in both optical SETI and optical astronomy. It is hoped that the observatory design will be emulated by both the professional and amateur communities. The modern-day OSETI observatory is one that is more affordable than ever. With the aid of reasonably priced automatic telescopes, low-cost PCs, software and signal processing boards, Optical SETI can become accessible to all nations, professional scientific groups, amateur astronomy societies and even individuals.

  3. Global Health Observatory (GHO)

    MedlinePlus

    ... repository Reports Country statistics Map gallery Standards Global Health Observatory (GHO) data Monitoring health for the SDGs ... relevant web pages on the theme. Monitoring the health goal: indicators of overall progress Mortality and global ...

  4. Observatory Improvements for SOFIA

    NASA Technical Reports Server (NTRS)

    Peralta, Robert A.; Jensen, Stephen C.

    2012-01-01

    The Stratospheric Observatory for Infrared Astronomy (SOFIA) is a joint project between NASA and Deutsches Zentrum fuer Luft- und Raumfahrt (DLR), the German Space Agency. SOFIA is based in a Boeing 747 SP and flown in the stratosphere to observe infrared wavelengths unobservable from the ground. In 2007 Dryden Flight Research Center (DFRC) inherited and began work on improving the plane and its telescope. The improvements continue today with upgrading the plane and improving the telescope. The Observatory Verification and Validation (V&V) process is to ensure that the observatory is where the program says it is. The Telescope Status Display (TSD) will provide any information from the on board network to monitors that will display the requested information. In order to assess risks to the program, one must work through the various threats associate with that risk. Once all the risks are closed the program can work towards improving the observatory.

  5. Use of the electrical aerosol detector as an indicator of the surface area of fine particles deposited in the lung.

    PubMed

    Wilson, William E; Stanek, John; Han, Hee-Siew Ryan; Johnson, Tim; Sakurai, Hiromu; Pui, David Y H; Turner, Jay; Chen, Da-Ren; Duthie, Scott

    2007-02-01

    Because of recent concerns about the health effects of ultrafine particles and the indication that particle toxicity is related to surface area, we have been examining techniques for measuring parameters related to the surface area of fine particles, especially in the 0.003- to 0.5-microm size range. In an earlier study, we suggested that the charge attached to particles, as measured by a prototype of the Electrical Aerosol Detector (EAD, TSI Inc., Model 3070), was related to the 1.16 power of the mobility diameter. An inspection of the pattern of particle deposition in the lung as a function of particle size suggested that the EAD measurement might be a useful indicator of the surface area of particles deposited in the lung. In this study, we calculate the particle surface area (micrometer squared) deposited in the lung per cubic centimeter of air inhaled as a function of particle size using atmospheric particle size distributions measured in Minneapolis, MN, and East St. Louis, IL. The correlations of powers of the mobility diameter, Dx, were highest for X = 1.1-1.6 for the deposited surface area and for X = 1.25 with the EAD signal. This overlap suggested a correspondence between the EAD signal and the deposited surface area. The correlation coefficients of the EAD signal and particle surface area deposited in the alveolar and tracheobronchial regions of the lung for three breathing patterns are in the range of Pearson's r = 0.91-0.95 (coefficient of determination, R2 = 0.82-0.90). These statistical relationships suggest that the EAD could serve as a useful indicator of particle surface area deposited in the lung in exposure and epidemiologic studies of the human health effects of atmospheric particles and as a measure of the potential surface area dose for the characterization of occupational environments.

  6. BINoculars: data reduction and analysis software for two-dimensional detectors in surface X-ray diffraction

    PubMed Central

    Roobol, Sander; Onderwaater, Willem; Drnec, Jakub; Felici, Roberto; Frenken, Joost

    2015-01-01

    BINoculars is a tool for data reduction and analysis of large sets of surface diffraction data that have been acquired with a two-dimensional X-ray detector. The intensity of each pixel of a two-dimensional detector is projected onto a three-dimensional grid in reciprocal-lattice coordinates using a binning algorithm. This allows for fast acquisition and processing of high-resolution data sets and results in a significant reduction of the size of the data set. The subsequent analysis then proceeds in reciprocal space. It has evolved from the specific needs of the ID03 beamline at the ESRF, but it has a modular design and can be easily adjusted and extended to work with data from other beamlines or from other measurement techniques. This paper covers the design and the underlying methods employed in this software package and explains how BINoculars can be used to improve the workflow of surface X-ray diffraction measurements and analysis. PMID:26306093

  7. CTK: A new CCD Camera at the University Observatory Jena

    NASA Astrophysics Data System (ADS)

    Mugrauer, M.

    2009-05-01

    The Cassegrain-Teleskop-Kamera (CTK) is a new CCD imager which is operated at the University Observatory Jena since begin of 2006. This article describes the main characteristics of the new camera. The properties of the CCD detector, the CTK image quality, as well as its detection limits for all filters are presented. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University.

  8. Development of a Silicon Drift Detector Array: An X-Ray Fluorescence Spectrometer for Remote Surface Mapping

    NASA Technical Reports Server (NTRS)

    Gaskin, Jessica A.; Carini, Gabriella A.; Wei, Chen; Elsner, Ronald F.; Kramer, Georgiana; De Geronimo, Gianluigi; Keister, Jeffrey W.; Zheng, Li; Ramsey, Brian D.; Rehak, Pavel; Siddons, D. Peter

    2009-01-01

    Over the past three years NASA Marshall Space Flight Center has been collaborating with Brookhaven National Laboratory to develop a modular Silicon Drift Detector (SDD) X-Ray Spectrometer (XRS) intended for fine surface mapping of the light elements of the moon. The value of fluorescence spectrometry for surface element mapping is underlined by the fact that the technique has recently been employed by three lunar orbiter missions; Kaguya, Chandrayaan-1, and Chang e. The SDD-XRS instrument we have been developing can operate at a low energy threshold (i.e. is capable of detecting Carbon), comparable energy resolution to Kaguya (<150 eV at 5.9 keV) and an order of magnitude lower power requirement, making much higher sensitivities possible. Furthermore, the intrinsic radiation resistance of the SDD makes it useful even in radiation-harsh environments such as that of Jupiter and its surrounding moons.

  9. Hawaiian Volcano Observatory

    USGS Publications Warehouse

    Venezky, Dina Y.; Orr, Tim R.

    2008-01-01

    Lava from Kilauea volcano flowing through a forest in the Royal Gardens subdivision, Hawai'i, in February 2008. The Hawaiian Volcano Observatory (HVO) monitors the volcanoes of Hawai'i and is located within Hawaiian Volcanoes National Park. HVO is one of five USGS Volcano Hazards Program observatories that monitor U.S. volcanoes for science and public safety. Learn more about Kilauea and HVO at http://hvo.wr.usgs.gov.

  10. Effect of panel alignment and surface finish on bond strength

    SciTech Connect

    Wouters, J.M.; Doe, P.J.; Baker, W.E.

    1991-10-01

    The flexural strength of bonded acrylic is tested as a function of panel alignment and bond surface finish. Bond strength was shown to be highly dependent on both parameters with only a narrow range of values yielding a high strength bond. This study was performed for the heavy water-containing acrylic vessel for the Sudbury Neutrino Observatory detector.

  11. Advanced Gravitational Wave Detectors

    NASA Astrophysics Data System (ADS)

    Blair, D. G.; Howell, E. J.; Ju, L.; Zhao, C.

    2012-02-01

    Part I. An Introduction to Gravitational Wave Astronomy and Detectors: 1. Gravitational waves D. G. Blair, L. Ju, C. Zhao and E. J. Howell; 2. Sources of gravitational waves D. G. Blair and E. J. Howell; 3. Gravitational wave detectors D. G. Blair, L. Ju, C. Zhao, H. Miao, E. J. Howell, and P. Barriga; 4. Gravitational wave data analysis B. S. Sathyaprakash and B. F. Schutz; 5. Network analysis L. Wen and B. F. Schutz; Part II. Current Laser Interferometer Detectors: Three Case Studies: 6. The Laser Interferometer Gravitational-Wave Observatory P. Fritschel; 7. The VIRGO detector S. Braccini; 8. GEO 600 H. Lück and H. Grote; Part III. Technology for Advanced Gravitational Wave Detectors: 9. Lasers for high optical power interferometers B. Willke and M. Frede; 10. Thermal noise, suspensions and test masses L. Ju, G. Harry and B. Lee; 11. Vibration isolation: Part 1. Seismic isolation for advanced LIGO B. Lantz; Part 2. Passive isolation J-C. Dumas; 12. Interferometer sensing and control P. Barriga; 13. Stabilizing interferometers against high optical power effects C. Zhao, L. Ju, S. Gras and D. G. Blair; Part IV. Technology for Third Generation Gravitational Wave Detectors: 14. Cryogenic interferometers J. Degallaix; 15. Quantum theory of laser-interferometer GW detectors H. Miao and Y. Chen; 16. ET. A third generation observatory M. Punturo and H. Lück; Index.

  12. Environmental effects on lunar astronomical observatories

    NASA Technical Reports Server (NTRS)

    Johnson, Stewart W.; Taylor, G. Jeffrey; Wetzel, John P.

    1992-01-01

    The Moon offers a stable platform with excellent seeing conditions for astronomical observations. Some troublesome aspects of the lunar environment will need to be overcome to realize the full potential of the Moon as an observatory site. Mitigation of negative effects of vacuum, thermal radiation, dust, and micrometeorite impact is feasible with careful engineering and operational planning. Shields against impact, dust, and solar radiation need to be developed. Means of restoring degraded surfaces are probably essential for optical and thermal control surfaces deployed in long-lifetime lunar facilities. Precursor missions should be planned to validate and enhance the understanding of the lunar environment (e.g., dust behavior without and with human presence) and to determine environmental effects on surfaces and components. Precursor missions should generate data useful in establishing keepout zones around observatory facilities where rocket launches and landings, mining, and vehicular traffic could be detrimental to observatory operation.

  13. STK: A new CCD camera at the University Observatory Jena

    NASA Astrophysics Data System (ADS)

    Mugrauer, M.; Berthold, T.

    2010-04-01

    The Schmidt-Teleskop-Kamera (STK) is a new CCD-imager, which is operated since begin of 2009 at the University Observatory Jena. This article describes the main characteristics of the new camera. The properties of the STK detector, the astrometry and image quality of the STK, as well as its detection limits at the 0.9 m telescope of the University Observatory Jena are presented. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University.

  14. Creating Griffith Observatory

    NASA Astrophysics Data System (ADS)

    Cook, Anthony

    2013-01-01

    Griffith Observatory has been the iconic symbol of the sky for southern California since it began its public mission on May 15, 1935. While the Observatory is widely known as being the gift of Col. Griffith J. Griffith (1850-1919), the story of how Griffith’s gift became reality involves many of the people better known for other contributions that made Los Angeles area an important center of astrophysics in the 20th century. Griffith began drawing up his plans for an observatory and science museum for the people of Los Angeles after looking at Saturn through the newly completed 60-inch reflector on Mt. Wilson. He realized the social impact that viewing the heavens could have if made freely available, and discussing the idea of a public observatory with Mt. Wilson Observatory’s founder, George Ellery Hale, and Director, Walter Adams. This resulted, in 1916, in a will specifying many of the features of Griffith Observatory, and establishing a committee managed trust fund to build it. Astronomy popularizer Mars Baumgardt convinced the committee at the Zeiss Planetarium projector would be appropriate for Griffith’s project after the planetarium was introduced in Germany in 1923. In 1930, the trust committee judged funds to be sufficient to start work on creating Griffith Observatory, and letters from the Committee requesting help in realizing the project were sent to Hale, Adams, Robert Millikan, and other area experts then engaged in creating the 200-inch telescope eventually destined for Palomar Mountain. A Scientific Advisory Committee, headed by Millikan, recommended that Caltech Physicist Edward Kurth be put in charge of building and exhibit design. Kurth, in turn, sought help from artist Russell Porter. The architecture firm of John C. Austin and Fredrick Ashley was selected to design the project, and they adopted the designs of Porter and Kurth. Philip Fox of the Adler Planetarium was enlisted to manage the completion of the Observatory and become its

  15. Development from the seafloor to the sea surface of the cabled NEMO-SN1 observatory in the Western Ionian Sea

    NASA Astrophysics Data System (ADS)

    Sparnocchia, Stefania; Beranzoli, Laura; Borghini, Mireno; Durante, Sara; Favali, Paolo; Giovanetti, Gabriele; Italiano, Francesco; Marinaro, Giuditta; Meccia, Virna; Papaleo, Riccardo; Riccobene, Giorgio; Schroeder, Katrin

    2015-04-01

    A prototype of cabled deep-sea observatory has been operating in real-time since 2005 in Southern Italy (East Sicily, 37°30' N - 15°06'E), at 2100 m water depth, 25 km from the harbor of the city of Catania. It is the first-established real-time node of the "European Multidisciplinary Seafloor and water column Observatory" (EMSO, http://www.emso-eu.org) a research infrastructure of the Sector Environment of ESFRI. In the present configuration it consists of two components: the multi-parametric station NEMO-SN1 (TSN branch) equipped with geophysical and environmental sensors for measurements at the seafloor, and the NEMO-OνDE station (TSS branch) equipped with 4 wideband hydrophones. A 28 km long electro-optical cable connects the observatory to a shore laboratory in the Catania harbor, hosting the data acquisition system and supplying power and data transmission to the underwater instrumentation. The NEMO-SN1 observatory is located in an area particularly suited to multidisciplinary studies. The site is one of the most seismically active areas of the Mediterranean (some of the strongest earthquakes occurred in 1169, 1693 and 1908, also causing very intense tsunami waves) and is close to Mount Etna, one of the largest and most active volcanoes in Europe. The deployment area is also a key site for monitoring deep-water dynamics in the Ionian Sea, connecting the Levantine basin to the southern Adriatic basin where intermediate and deep waters are formed, and finally to the western Mediterranean Sea via the Strait of Sicily. The observatory is being further developed under EMSO MedIT (http://www.emso-medit.it/en/), a structural enhancement project contributing to the consolidation and enhancement of the European research infrastructure EMSO in Italian Convergence Regions. In this framework, a new Junction Box will be connected to the TSN branch and will provide wired and wireless (acoustic connections) for seafloor platforms and moorings. This will allow the

  16. Charged particle spectra obtained with the Mars Science Laboratory Radiation Assessment Detector (MSL/RAD) on the surface of Mars

    NASA Astrophysics Data System (ADS)

    Ehresmann, Bent; Zeitlin, Cary; Hassler, Donald M.; Wimmer-Schweingruber, Robert F.; Böhm, Eckart; Böttcher, Stephan; Brinza, David E.; Burmeister, Sönke; Guo, Jingnan; Köhler, Jan; Martin, Cesar; Posner, Arik; Rafkin, Scot; Reitz, Günther

    2014-03-01

    The Radiation Assessment Detector (RAD)—situated inside the Mars Science Laboratory's Curiosity rover—is the first ever instrument to measure the energetic particle radiation environment on the surface of Mars. To fully understand the influence of this surface radiation field in terms of potential hazard to life, a detailed knowledge of its composition is necessary. Charged particles are a major component of this environment, both galactic cosmic rays propagating to the Martian surface and secondary particles created by interactions of these cosmic rays with the atoms of the Martian atmosphere and soil. Here we present particle fluxes for a wide range of ion species, providing detailed energy spectra in the low-energy range (up to several hundred MeV/nucleon particle energy), and integral fluxes for higher energies. In addition to being crucial for the understanding of the hazards of this radiation to possible future manned missions to Mars, the data reported here provide valuable input for evaluating and validating particle transport models currently used to estimate the radiation environment on Mars and elsewhere in space. It is now possible for the first time to compare model results for expected surface particle fluxes with actual ground-based measurements.

  17. The Apollo lunar surface experiment package suprathermal ion detector experiment. [bibliographies

    NASA Technical Reports Server (NTRS)

    1975-01-01

    A compilation of reports and scientific papers is presented for the following topics: (1) the lunar ionosphere; (2) electric potential of the lunar surface; (3) ion activity on the lunar nightside; (4) bow shock protons; (5) magnetosheath and magnetotail; (6) solar wind-neutral gas cloud interactions at the lunar surface; (7) penetrating solar particles; and (8) rocket exhaust products from Apollo missions. Descriptions and photographs of ion detecting equipment at the lunar sites of Apollo 12, 13, 14, and 15 are given.

  18. A novel single-ended readout depth-of-interaction PET detector fabricated using sub-surface laser engraving

    NASA Astrophysics Data System (ADS)

    Uchida, H.; Sakai, T.; Yamauchi, H.; Hakamata, K.; Shimizu, K.; Yamashita, T.

    2016-09-01

    We propose a novel scintillation detector design for positron emission tomography (PET), which has depth of interaction (DOI) capability and uses a single-ended readout scheme. The DOI detector contains a pair of crystal bars segmented using sub-surface laser engraving (SSLE). The two crystal bars are optically coupled to each other at their top segments and are coupled to two photo-sensors at their bottom segments. Initially, we evaluated the performance of different designs of single crystal bars coupled to photomultiplier tubes at both ends. We found that segmentation by SSLE results in superior performance compared to the conventional method. As the next step, we constructed a crystal unit composed of a 3  ×  3  ×  20 mm3 crystal bar pair, with each bar containing four layers segmented using the SSLE. We measured the DOI performance by changing the optical conditions for the crystal unit. Based on the experimental results, we then assessed the detector performance in terms of the DOI capability by evaluating the position error, energy resolution, and light collection efficiency for various crystal unit designs with different bar sizes and a different number of layers (four to seven layers). DOI encoding with small position error was achieved for crystal units composed of a 3  ×  3  ×  20 mm3 LYSO bar pair having up to seven layers, and with those composed of a 2  ×  2  ×  20 mm3 LYSO bar pair having up to six layers. The energy resolution of the segment in the seven-layer 3  ×  3  ×  20 mm3 crystal bar pair was 9.3%-15.5% for 662 keV gamma-rays, where the segments closer to the photo-sensors provided better energy resolution. SSLE provides high geometrical accuracy at low production cost due to the simplicity of the crystal assembly. Therefore, the proposed DOI detector is expected to be an attractive choice for practical small-bore PET systems dedicated to imaging of the brain

  19. A novel single-ended readout depth-of-interaction PET detector fabricated using sub-surface laser engraving

    NASA Astrophysics Data System (ADS)

    Uchida, H.; Sakai, T.; Yamauchi, H.; Hakamata, K.; Shimizu, K.; Yamashita, T.

    2016-09-01

    We propose a novel scintillation detector design for positron emission tomography (PET), which has depth of interaction (DOI) capability and uses a single-ended readout scheme. The DOI detector contains a pair of crystal bars segmented using sub-surface laser engraving (SSLE). The two crystal bars are optically coupled to each other at their top segments and are coupled to two photo-sensors at their bottom segments. Initially, we evaluated the performance of different designs of single crystal bars coupled to photomultiplier tubes at both ends. We found that segmentation by SSLE results in superior performance compared to the conventional method. As the next step, we constructed a crystal unit composed of a 3  ×  3  ×  20 mm3 crystal bar pair, with each bar containing four layers segmented using the SSLE. We measured the DOI performance by changing the optical conditions for the crystal unit. Based on the experimental results, we then assessed the detector performance in terms of the DOI capability by evaluating the position error, energy resolution, and light collection efficiency for various crystal unit designs with different bar sizes and a different number of layers (four to seven layers). DOI encoding with small position error was achieved for crystal units composed of a 3  ×  3  ×  20 mm3 LYSO bar pair having up to seven layers, and with those composed of a 2  ×  2  ×  20 mm3 LYSO bar pair having up to six layers. The energy resolution of the segment in the seven-layer 3  ×  3  ×  20 mm3 crystal bar pair was 9.3%–15.5% for 662 keV gamma-rays, where the segments closer to the photo-sensors provided better energy resolution. SSLE provides high geometrical accuracy at low production cost due to the simplicity of the crystal assembly. Therefore, the proposed DOI detector is expected to be an attractive choice for practical small-bore PET systems dedicated to imaging of the brain

  20. Iranian National Observatory

    NASA Astrophysics Data System (ADS)

    Khosroshahi, H. G.; Danesh, A.; Molaeinezhad, A.

    2016-09-01

    The Iranian National Observatory is under construction at an altitude of 3600m at Gargash summit 300km southern Tehran. The site selection was concluded in 2007 and the site monitoring activities have begun since then, which indicates a high quality of the site with a median seeing of 0.7 arcsec through the year. One of the major observing facilities of the observatory is a 3.4m Alt-Az Ritchey-Chretien optical telescope which is currently under design. This f/11 telescope will be equipped with high resolution medium-wide field imaging cameras as well as medium and high resolution spectrographs. In this review, I will give an overview of astronomy research and education in Iran. Then I will go through the past and present activities of the Iranian National Observatory project including the site quality, telescope specifications and instrument capabilities.

  1. The Collaborative Heliophysics Observatory

    NASA Astrophysics Data System (ADS)

    Hurlburt, N.; Freeland, S.; Cheung, M.; Bose, P.

    2007-12-01

    The Collaborative Heliophysics Observatory (CHO) would provide a robust framework and enabling tools to fully utilize the VOs for scientific discovery and collaboration. Scientists across the realm of heliophysics would be able to create, use and share applications -- either as services using familiar tools or through intuitive workflows -- that orchestrate access to data across all virtual observatories. These applications can be shared freely knowing that proper recognition of data and processing components are acknowledged; that erroneous use of data is flagged; and that results from the analysis runs will in themselves be shared Ð all in a transparent and automatic fashion. In addition, the CHO would incorporate cross-VO models and tools to weave the various virtual observatories into a unified system. These provide starting points for interactions across the solar/heliospheric and heliospheric/magnetospheric boundaries.

  2. Enhanced quantum efficiency of high-purity silicon imaging detectors by ultralow temperature surface modification using Sb doping

    NASA Technical Reports Server (NTRS)

    Blacksberg, Jordana; Hoenk, Michael E.; Elliott, S. Tom; Holland, Stephen E.; Nikzad, Shouleh

    2005-01-01

    A low temperature process for Sb doping of silicon has been developed as a backsurface treatment for high-purity n-type imaging detectors. Molecular beam epitaxy (MBE) is used to achieve very high dopant incorporation in a thin, surface-confined layer. The growth temperature is kept below 450 (deg)C for compatibility with Al-metallized devices. Imaging with MBE-modified 1kx1k charge coupled devices (CCDs) operated in full depletion has been demonstrated. Dark current is comparable to the state-of-the-art process, which requires a high temperature step. Quantum efficiency is improved, especially in the UV, for thin doped layers placed closer to the backsurface. Near 100% internal quantum efficiency has been demonstrated in the ultraviolet for a CCD with a 1.5 nm silicon cap layer.

  3. Graphene oxide/carbon nanoparticle thin film based IR detector: Surface properties and device characterization

    SciTech Connect

    Chowdhury, Farzana Aktar; Hossain, Mohammad Abul; Uchida, Koji; Tamura, Takahiro; Sugawa, Kosuke; Mochida, Tomoaki; Otsuki, Joe; Mohiuddin, Tariq; Boby, Monny Akter; Alam, Mohammad Sahabul

    2015-10-15

    This work deals with the synthesis, characterization, and application of carbon nanoparticles (CNP) adorned graphene oxide (GO) nanocomposite materials. Here we mainly focus on an emerging topic in modern research field presenting GO-CNP nanocomposite as a infrared (IR) radiation detector device. GO-CNP thin film devices were fabricated from liquid phase at ambient condition where no modifying treatments were necessary. It works with no cooling treatment and also for stationary objects. A sharp response of human body IR radiation was detected with time constants of 3 and 36 sec and radiation responsivity was 3 mAW{sup −1}. The current also rises for quite a long time before saturation. This work discusses state-of-the-art material developing technique based on near-infrared photon absorption and their use in field deployable instrument for real-world applications. GO-CNP-based thin solid composite films also offer its potentiality to be utilized as p-type absorber material in thin film solar cell, as well.

  4. Wavelength-selective visible-light detector based on integrated graphene transistor and surface plasmon coupler

    NASA Astrophysics Data System (ADS)

    Smith, Christian W.; Maukonen, Doug; Peale, R. E.; Fredricksen, C. J.; Ishigami, M.; Cleary, J. W.

    2014-06-01

    We have invented a novel photodetector by mating a surface plasmon resonance coupler with a graphene field effect transistor. The device enables wavelength selectivity for spectral sensing applications. Surface plasmon polaritons (SPPs) are generated in a 50 nm thick Ag film on the surface of a prism in the Kretschmann configuration positioned 500 nm from a graphene FET. Incident photons of a given wavelength excite SPPs at a specific incidence angle. These SPP fields excite a transient current whose amplitude follows the angular resonance spectrum of the SPP absorption feature. Though demonstrated first at visible wavelengths, the approach can be extended far into the infrared. We also demonstrate that the resonant current is strongly modulated by gate bias applied to the FET, providing a clear path towards large-scale spectral imagers with locally addressable pixels.

  5. The High-Altitude Water Cherenkov Observatory

    NASA Astrophysics Data System (ADS)

    Mostafá, Miguel A.

    2014-10-01

    The High-Altitude Water Cherenkov (HAWC) observatory is a large field of view, continuously operated, TeV γ-ray experiment under construction at 4,100 m a.s.l. in Mexico. The HAWC observatory will have an order of magnitude better sensitivity, angular resolution, and background rejection than its predecessor, the Milagro experiment. The improved performance will allow us to detect both the transient and steady emissions, to study the Galactic diffuse emission at TeV energies, and to measure or constrain the TeV spectra of GeV γ-ray sources. In addition, HAWC will be the only ground-based instrument capable of detecting prompt emission from γ-ray bursts above 50 GeV. The HAWC observatory will consist of an array of 300 water Cherenkov detectors (WCDs), each with four photomultiplier tubes. This array is currently under construction on the flanks of the Sierra Negra volcano near the city of Puebla, Mexico. The first 30 WCDs (forming an array approximately the size of Milagro) were deployed in Summer 2012, and 100 WCDs will be taking data by May, 2013. We present in this paper the motivation for constructing the HAWC observatory, the status of the deployment, and the first results from the constantly growing array.

  6. Arecibo Observatory for All

    NASA Astrophysics Data System (ADS)

    Isidro, Gloria M.; Pantoja, C. A.; Bartus, P.; La Rosa, C.

    2006-12-01

    We describe new materials available at Arecibo Observatory for visitors with visual impairments. These materials include a guide in Braille that describes the telescope, some basic terms used in radio astronomy and frequently asked questions. We have also designed a tactile model of the telescope. We are interested that blind visitors can participate of the excitement of the visit to the worlds largest radio telescope. We would like to thank the "Fundacion Comunitaria de Puerto Rico" for the scholarship that allowed GMI to work on this project. We would like to express our gratitude to the Arecibo Observatory/NAIC for their support.

  7. WFIRST Observatory Performance

    NASA Technical Reports Server (NTRS)

    Kruk, Jeffrey W.

    2012-01-01

    The WFIRST observatory will be a powerful and flexible wide-field near-infrared facility. The planned surveys will provide data applicable to an enormous variety of astrophysical science. This presentation will provide a description of the observatory and its performance characteristics. This will include a discussion of the point spread function, signal-to-noise budgets for representative observing scenarios and the corresponding limiting sensitivity. Emphasis will be given to providing prospective Guest Observers with information needed to begin thinking about new observing programs.

  8. Cascades Volcano Observatory

    USGS Publications Warehouse

    Venezky, Dina Y.; Driedger, Carolyn; Pallister, John

    2008-01-01

    Washington's Mount St. Helens volcano reawakens explosively on October 1, 2004, after 18 years of quiescence. Scientists at the U.S. Geological Survey's Cascades Volcano Observatory (CVO) study and observe Mount St. Helens and other volcanoes of the Cascade Range in Washington, Oregon, and northern California that hold potential for future eruptions. CVO is one of five USGS Volcano Hazards Program observatories that monitor U.S. volcanoes for science and public safety. Learn more about Mount St. Helens and CVO at http://vulcan.wr.usgs.gov/.

  9. Long Valley Observatory

    USGS Publications Warehouse

    Venezky, Dina Y.; Hill, David

    2008-01-01

    The ~300-year-old lava on Paoha Island in Mono Lake was produced by the most recent eruption in the Long Valley Caldera area in east-central California. The Long Valley Caldera was formed by a massive volcanic eruption 760,000 years ago. The region is monitored by the Long Valley Observatory (LVO), one of five USGS Volcano Hazards Program observatories that monitor U.S. volcanoes for science and public safety. Learn more about the Long Valley Caldera region and LVO at http://volcanoes.usgs.gov/lvo.

  10. Building a Galactic Scale Gravitational Wave Observatory

    NASA Astrophysics Data System (ADS)

    McLaughlin, Maura

    2016-03-01

    Pulsars are rapidly rotating neutron stars with phenomenal rotational stability that can be used as celestial clocks in a variety of fundamental physics experiences. One of these experiments involves using a pulsar timing array of precisely timed millisecond pulsars to detect perturbations due to gravitational waves. The low frequency gravitational waves detectable through pulsar timing will most likely result from an ensemble of supermassive black hole binaries. I will introduce the efforts of the North American Nanohertz Observatory for Gravitational Waves (NANOGrav), a collaboration that monitors over 50 millisecond pulsars with the Green Bank Telescope and the Arecibo Observatory, with a focus on our observation and data analysis methods. I will also describe how NANOGrav has joined international partners through the International Pulsar Timing Array to form a low-frequency gravitational wave detector of unprecedented sensitivity.

  11. Strasbourg's "First" astronomical observatory

    NASA Astrophysics Data System (ADS)

    Heck, André

    2011-08-01

    The turret lantern located at the top of the Strasbourg Hospital Gate is generally considered as the first astronomical observatory of the city, but such a qualification must be treated with caution. The thesis of this paper is that the idea of a tower-observatory was brought back by a local scholar, Julius Reichelt (1637-1717), after he made a trip to Northern Europe around 1666 and saw the "Rundetårn" (Round Tower) recently completed in Copenhagen. There, however, a terrace allowed (and still allows) the full viewing of the sky, and especially of the zenith area where the atmospheric transparency is best. However, there is no such terrace in Strasbourg around the Hospital Gate lantern. Reichelt had also visited Johannes Hevelius who was then developing advanced observational astronomy in Gdansk, but nothing of the kind followed in Strasbourg. Rather, the Hospital Gate observatory was built essentially for the prestige of the city and for the notoriety of the university, and the users of this observing post did not make any significant contributions to the progress of astronomical knowledge. We conclude that the Hospital Gate observatory was only used for rudimentary viewing of bright celestial objects or phenomena relatively low on the horizon.

  12. The IT Observatory.

    ERIC Educational Resources Information Center

    Kent, Kai Iok Tong; Sousa, Antonio C. M.

    1999-01-01

    Describes the IT Observatory, a service of the Macau Productivity and Technology center (CPTTM) that provides information on demand using information technology. The CPTTM is a nonprofit organization funded by the Macau government and private businesses to enhance the productivity of Macau businesses by introducing new technologies and new…

  13. High Energy Astronomy Observatory

    NASA Technical Reports Server (NTRS)

    1980-01-01

    An overview of the High Energy Astronomy Observatory 2 contributions to X-ray astronomy is presented along with a brief description of the satellite and onboard telescope. Observations relating to galaxies and galactic clusters, black holes, supernova remnants, quasars, and cosmology are discussed.

  14. Torun Radio Astronomy Observatory

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Torun Center for Astronomy is located at Piwnice, 15 km north of Torun, Poland. A part of the Faculty of Physics and Astronomy of the Nicolaus Copernicus University, it was created by the union of Torun Radio Astronomy Observatory (TRAO) and the Institute of Astronomy on 1 January 1997....

  15. Arecibo Observatory for All

    ERIC Educational Resources Information Center

    Bartus, P.; Isidro, G. M.; La Rosa, C.; Pantoja, C. A.

    2007-01-01

    We describe new materials available at the Arecibo Observatory for visitors with visual impairments. These materials include a guide in Braille that describes the telescope, explains some basic terms used in radio astronomy, and lists frequently asked questions. We have also designed a tactile model of the telescope. Our interest is in enabling…

  16. Radio detection of cosmic ray induced air showers at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Fliescher, Stefan; Pierre Auger Collaboration

    2012-01-01

    AERA—the Auger Engineering Radio Array—is currently being set up at the southern site of the Pierre Auger Observatory. AERA will explore the potential of the radio-detection technique to cosmic ray induced air showers with respect to the next generation of large-scale surface detectors. As AERA is co-located with the low-energy enhancements of the Pierre Auger Observatory, the observation of air showers in coincidence with the Auger surface and fluorescence detector will allow to study the radio emission processes in detail and to calibrate the radio signal. Finally, the combined reconstruction of shower parameters with three independent techniques promises new insights into the nature of cosmic rays in the transition region from 1017 to 1019 eV.Besides the detection of coherent radiation in the MHz frequency range, the setups AMBER—Air-shower Microwave Bremsstrahlung Experimental Radiometer—and MIDAS—MIcrowave Detection of Air Showers—prepare to check the possibility to detect air showers due the emission of molecular bremsstrahlung in the GHz range at the Auger site.This article presents the status of the radio-detection setups and discusses their physics potential as well as experimental challenges. Special focus is laid on the first stage of AERA which is the startup to the construction of a 20 km2 radio array.

  17. The Liverpool Bay Coastal Observatory

    NASA Astrophysics Data System (ADS)

    Howarth, John; Palmer, Matthew

    2011-11-01

    A pilot Coastal Observatory has been established in Liverpool Bay which integrates (near) real-time measurements with coupled models and whose results are displayed on the web. The aim is to understand the functioning of coastal seas, their response to natural forcing and the consequences of human activity. The eastern Irish Sea is an apt test site, since it encompasses a comprehensive range of processes found in tidally dominated coastal seas, including near-shore physical and biogeochemical processes influenced by estuarine inflows, where both vertical and horizontal gradients are important. Applications include hypernutrification, since the region receives significantly elevated levels of nutrient inputs, shoreline management (coastal flooding and beach erosion/accretion), and understanding present conditions to predict the impact of climate change (for instance if the number and severity of storms, or of high or low river flows, change). The integrated measurement suite which started in August 2002 covers a range of space and time scales. It includes in situ time series, four to six weekly regional water column surveys, an instrumented ferry, a shore-based HF radar system measuring surface currents and waves, coastal tide gauges and visible and infra-red satellite data. The time series enable definition of the seasonal cycle, its inter-annual variability and provide a baseline from which the relative importance of events can be quantified. A suite of nested 3D hydrodynamic, wave and ecosystem models is run daily, focusing on the observatory area by covering the ocean/shelf of northwest Europe (at 12-km resolution) and the Irish Sea (at 1.8 km), and Liverpool Bay at the highest resolution of 200 m. The measurements test the models against events as they happen in a truly 3D context. All measurements and model outputs are displayed freely on the Coastal Observatory website (http://cobs.pol.ac.uk) for an audience of researchers, education, coastal managers and the

  18. Evaluation of a gas chromatograph with a novel surface acoustic wave detector (SAW GC) for screening of volatile organic compounds in Hanford waste tank samples

    SciTech Connect

    Lockrem, L.L.

    1998-01-12

    A novel instrument, a gas chromatograph with a Surface Acoustic Wave Detector (SAW GC), was evaluated for the screening of organic compounds in Hanford tank headspace vapors. Calibration data were developed for the most common organic compounds, and the accuracy and precision were measured with a certified standard. The instrument was tested with headspace samples collected from seven Hanford waste tanks.

  19. Anisotropy studies around the Galactic Centre at EeV energies with the Auger Observatory

    SciTech Connect

    Aglietta, M.; Aguirre, C.; Allard, D.; Allekotte, I.; Allison, P.; Alvarez, C.; Alvarez-Muniz, J.; Ambrosio, M.; Anchordoqui, L.; Anjos, J.C.; Aramo, C.; /Centro Atomico Bariloche /Buenos Aires, IAFE /Buenos Aires, CONICET /Pierre Auger Observ. /La Plata U. /Natl. Tech. U., San Rafael /Adelaide U. /Catholic U. of Bolivia, La Paz /Bolivia U. /Rio de Janeiro, CBPF /Sao Paulo U.

    2006-07-01

    Data from the Pierre Auger Observatory are analyzed to search for anisotropies near the direction of the Galactic Centre at EeV energies. The exposure of the surface array in this part of the sky is already significantly larger than that of the fore-runner experiments. Our results do not support previous findings of localized excesses in the AGASA and SUGAR data. We set an upper bound on a point-like flux of cosmic rays arriving from the Galactic Centre which excludes several scenarios predicting sources of EeV neutrons from Sagittarius A. Also the events detected simultaneously by the surface and fluorescence detectors (the ''hybrid'' data set), which have better pointing accuracy but are less numerous than those of the surface array alone, do not show any significant localized excess from this direction.

  20. OSO-7 Orbiting Solar Observatory program

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The seventh Orbiting Solar Observatory (OSO-7) in the continuing series designed to gather solar and celestial data that cannot be obtained from the earth's surface is described. OSO-7 was launched September 29, 1971. It has been highly successful in returning scientific data giving new and important information about solar flare development, coronal temperature variations, streamer dynamics of plasma flow, and solar nuclear processes. OSO-7 is expected to have sufficient lifetime to permit data comparisons with the Skylab A mission during 1973. The OSO-7 is a second generation observatory. It is about twice as large and heavy as its predecessors, giving it considerably greater capability for scientific measurements. This report reviews mission objectives, flight history, and scientific experiments; describes the observatory; briefly compares OSO-7 with the first six OSO's; and summarizes the performance of OSO-7.

  1. High Energy Astronomy Observatory program

    NASA Technical Reports Server (NTRS)

    Wojtalik, F. S.

    1979-01-01

    The series of three orbiting high energy astronomy observatories that comprise the HEAO program are described. Several unique designs as well as the attitude control and determination system, used for observatory scan rotation of the first and third missions and for precision pointing on the second mission, are analyzed. Attention is given to observatory requirements, design characteristics, and the RGA performance summary.

  2. NASA's Great Observatories: Paper Model.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC.

    This educational brief discusses observatory stations built by the National Aeronautics and Space Administration (NASA) for looking at the universe. This activity for grades 5-12 has students build paper models of the observatories and study their history, features, and functions. Templates for the observatories are included. (MVL)

  3. Design of a Lunar Farside Observatory

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The design of a mantendable lunar farside observatory and science base is presented. A farside observatory will allow high accuracy astronomical observations, as well as the opportunity to perform geological and low gravity studies on the Moon. The requirements of the observatory and its support facilities are determined, and a preliminary timeline for the project development is presented. The primary areas of investigation include observatory equipment, communications, habitation, and surface operations. Each area was investigated to determine the available options, and each option was evaluated to determine the advantages and disadvantages. The options selected for incorporation into the design of the farside base are presented. The observatory equipment deemed most suitable for placement on the lunar farside consist of large optical and radio arrays and seismic equipment. A communications system consisting of a temporary satellite about the L sub 2 libration point and followed by a satellite at the stable L sub 5 libration point was selected. A space station common module was found to be the most practical option for housing the astronauts at the base. Finally, a support system based upon robotic construction vehicles and the use of lunar materials was determined to be a necessary component of the base.

  4. Technical Note: Out-of-field dose measurement at near surface with plastic scintillator detector.

    PubMed

    Bourgouin, Alexandra; Varfalvy, Nicolas; Archambault, Louis

    2016-01-01

    Out-of-field dose depends on multiple factors, making peripheral dosimetry com-plex. Only a few dosimeters have the required features for measuring peripheral dose. Plastic scintillator dosimeters (PSDs) offer numerous dosimetric advantages as required for out-of-field dosimetry. The purpose of this study is to determine the potential of using PSD as a surface peripheral dosimeter. Measurements were performed with a parallel-plate ion chamber, a small volume ion chamber, and with a PSD. Lateral-dose measurements (LDM) at 0.5 cm depth and depth-dose curve (PDD) were made and compared to the dose calculation provided by a treatment planning system (TPS). This study shows that a PSD can measure a dose as low as 0.51 ± 0.17 cGy for photon beam and 0.58 ± 0.20 cGy for electron beam with a difference of 0.2 and 0.1 cGy compared to a parallel-plate ion chamber. This study demonstrates the potential of using PSD as an out-of-field dosimeter since measure-ments with PSD avoid averaging over a too-large depth, at 1 mm diameter, and can make precise measurement at very low dose. Also, electronic equilibrium is easier to reach with PSD due to its small sensitive volume and its water equivalence. PMID:27685131

  5. Alaska Volcano Observatory

    USGS Publications Warehouse

    Venezky, Dina Y.; Murray, Tom; Read, Cyrus

    2008-01-01

    Steam plume from the 2006 eruption of Augustine volcano in Cook Inlet, Alaska. Explosive ash-producing eruptions from Alaska's 40+ historically active volcanoes pose hazards to aviation, including commercial aircraft flying the busy North Pacific routes between North America and Asia. The Alaska Volcano Observatory (AVO) monitors these volcanoes to provide forecasts of eruptive activity. AVO is a joint program of the U.S. Geological Survey (USGS), the Geophysical Institute of the University of Alaska Fairbanks (UAFGI), and the State of Alaska Division of Geological and Geophysical Surveys (ADGGS). AVO is one of five USGS Volcano Hazards Program observatories that monitor U.S. volcanoes for science and public safety. Learn more about Augustine volcano and AVO at http://www.avo.alaska.edu.

  6. Mount Wilson Observatory

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Mount Wilson Observatory, located in the San Gabriel Mountains near Pasadena, California, was founded in 1904 by George Ellery Hale with financial support from Andrew Carnegie. In the 1920s and 1930s, working at the 2.5 m Hooker telescope, Edwin Hubble made two of the most important discoveries in the history of astronomy: first, that `nebulae' are actually island universes—galaxies—each with bil...

  7. Jodrell Bank Observatory

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    The Jodrell Bank Observatory is part of the University of Manchester and was founded by Bernard Lovell in December 1945. Its prime instrument, the 76 m, MK1 radio-telescope, was completed in 1957. It was given a major upgrade in 1971 and is now known as the Lovell Telescope. In its early years it pioneered the technique of long baseline interferometry which led to the discovery of quasars. A majo...

  8. Arecibo Observatory for All

    NASA Astrophysics Data System (ADS)

    Bartus, P.; Isidro, G. M.; La Rosa, C.; Pantoja, C. A.

    We describe new materials available at the Arecibo Observatory for visitors with visual impairments. These materials include a guide in Braille that describes the telescope, explains some basic terms used in radio astronomy, and lists frequently asked questions. We have also designed a tactile model of the telescope. Our interest is in enabling blind visitors to participate in the excitement of visiting the world's largest radio telescope.

  9. The Russian Virtual Observatory

    NASA Astrophysics Data System (ADS)

    Dluzhnevskaya, O. B.; Malkov, O. Yu.; Kilpio, A. A.; Kilpio, E. Yu.; Kovaleva, D. A.; Sat, L. A.

    The Russian Virtual Observatory (RVO) will be an integral component of the International Virtual Observatory (IVO). The RVO has the main goal of integrating resources of astronomical data accumulated in Russian observatories and institutions (databases, archives, digitized glass libraries, bibliographic data, a remote access system to information and technical resources of telescopes etc.), and providing transparent access for scientific and educational purposes to the distributed information and data services that comprise its content. Another goal of the RVO is to provide Russian astronomers with on-line access to the rich volumes of data and metadata that have been, and will continue to be, produced by astronomical survey projects. Centre for Astronomical Data (CAD), among other Russian institutions, has had the greatest experience in collecting and distributing astronomical data for more than 20 years. Some hundreds of catalogs and journal tables are currently available from the CAD repository. More recently, mirrors of main astronomical data resources (VizieR, ADS, etc) are now maintained in CAD. Besides, CAD accumulates and makes available for the astronomical community information on principal Russian astronomical resources.

  10. Megalithic observatory Kokino

    NASA Astrophysics Data System (ADS)

    Cenev, Gj.

    2006-05-01

    In 2001, on the footpath of a mountain peak, near the village of Kokino, archeologist Jovica Stankovski discovered an archeological site from The Bronze Age. The site occupies a large area and is scaled in two levels. Several stone seats (thrones) are dominant in this site and they are pointing towards the east horizon. The high concentration of the movable archeological material found on the upper platform probably indicates its use in a function containing still unknown cult activities. Due to precise measurements and a detailed archaeoastronomical analysis of the site performed in the past three years by Gjore Cenev, physicist from the Planetarium in Skopje, it was shown that the site has characteristics of a sacred site, but also of a Megalithic Observatory. The markers found in this observatory point on the summer and winter solstices and spring and autumn equinoxes. It can be seen that on both sides of the solstice markers, that there are markers for establishing Moon's positions. The markers are crafted in such a way that for example on days when special rites were performed (harvest rites for example) the Sun filled a narrow space of the marker and special ray lighted the man sitting on only one of the thrones, which of course had a special meaning. According to the positions of the markers that are used for Sun marking, especially on the solstice days, it was calculated that this observatory dates from 1800 B.C.

  11. A novel surface-sensitive X-ray absorption spectroscopic detector to study the thermal decomposition of cathode materials for Li-ion batteries

    NASA Astrophysics Data System (ADS)

    Nonaka, Takamasa; Okuda, Chikaaki; Oka, Hideaki; Nishimura, Yusaku F.; Makimura, Yoshinari; Kondo, Yasuhito; Dohmae, Kazuhiko; Takeuchi, Yoji

    2016-09-01

    A surface-sensitive conversion-electron-yield X-ray absorption fine structure (CEY-XAFS) detector that operates at elevated temperatures is developed to investigate the thermal decomposition of cathode materials for Li-ion batteries. The detector enables measurements with the sample temperature controlled from room temperature up to 450 °C. The detector is applied to the LiNi0.75Co0.15Al0.05Mg0.05O2 cathode material at 0% state of charge (SOC) and 50% SOC to examine the chemical changes that occur during heating in the absence of an electrolyte. The combination of surface-sensitive CEY-XAFS and bulk-sensitive transmission-mode XAFS shows that the reduction of Ni and Co ions begins at the surface of the cathode particles at around 150 °C, and propagates inside the particle upon further heating. These changes with heating are irreversible and are more obvious at 50% SOC than at 0% SOC. The fraction of reduced Ni ions is larger than that of reduced Co ions. These results demonstrate the capability of the developed detector to obtain important information for the safe employment of this cathode material in Li-ion batteries.

  12. Search for first harmonic modulation in the right ascension distribution of cosmic rays detected at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Pierre Auger Collaboration; Abreu, P.; Aglietta, M.; Ahn, E. J.; Albuquerque, I. F. M.; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Antičić, T.; Aramo, C.; Arganda, E.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Bäcker, T.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Beatty, J. J.; Becker, B. R.; Becker, K. H.; Bellido, J. A.; Benzvi, S.; Berat, C.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Blümer, H.; Boháčová, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brogueira, P.; Brown, W. C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Burton, R. E.; Caballero-Mora, K. S.; Caramete, L.; Caruso, R.; Castellina, A.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Chiavassa, A.; Chinellato, J. A.; Chou, A.; Chudoba, J.; Clay, R. W.; Coluccia, M. R.; Conceição, R.; Contreras, F.; Cook, H.; Cooper, M. J.; Coppens, J.; Cordier, A.; Cotti, U.; Coutu, S.; Covault, C. E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; de Domenico, M.; de Donato, C.; de Jong, S. J.; de La Vega, G.; de Mello, W. J. M.; de Mello Neto, J. R. T.; de Mitri, I.; de Souza, V.; de Vries, K. D.; Decerprit, G.; Del Peral, L.; Deligny, O.; Dembinski, H.; Denkiewicz, A.; di Giulio, C.; Diaz, J. C.; Díaz Castro, M. L.; Diep, P. N.; Dobrigkeit, C.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; Dos Anjos, J. C.; Dova, M. T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C. O.; Etchegoyen, A.; Facal San Luis, P.; Falcke, H.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Ferrero, A.; Fick, B.; Filevich, A.; Filipčič, A.; Fliescher, S.; Fracchiolla, C. E.; Fraenkel, E. D.; Fröhlich, U.; Fuchs, B.; Gamarra, R. F.; Gambetta, S.; García, B.; García Gámez, D.; Garcia-Pinto, D.; Gascon, A.; Gemmeke, H.; Gesterling, K.; Ghia, P. L.; Giaccari, U.; Giller, M.; Glass, H.; Gold, M. S.; Golup, G.; Gomez Albarracin, F.; Gómez Berisso, M.; Gonçalves, P.; Gonzalez, D.; Gonzalez, J. G.; Gookin, B.; Góra, D.; Gorgi, A.; Gouffon, P.; Gozzini, S. R.; Grashorn, E.; Grebe, S.; Griffith, N.; Grigat, M.; Grillo, A. F.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Hague, J. D.; Hansen, P.; Harari, D.; Harmsma, S.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A. E.; Hojvat, C.; Holmes, V. C.; Homola, P.; Hörandel, J. R.; Horneffer, A.; Hrabovský, M.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jiraskova, S.; Kadija, K.; Kampert, K. H.; Karhan, P.; Karova, T.; Kasper, P.; Kégl, B.; Keilhauer, B.; Keivani, A.; Kelley, J. L.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D.-H.; Kotera, K.; Krohm, N.; Krömer, O.; Kruppke-Hansen, D.; Kuehn, F.; Kuempel, D.; Kulbartz, J. K.; Kunka, N.; La Rosa, G.; Lachaud, C.; Lautridou, P.; Leão, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Lemiere, A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; López, R.; Lopez Agüera, A.; Louedec, K.; Lozano Bahilo, J.; Lucero, A.; Ludwig, M.; Lyberis, H.; Macolino, C.; Maldera, S.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, V.; Maris, I. C.; Marquez Falcon, H. R.; Marsella, G.; Martello, D.; Martin, L.; Martínez Bravo, O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mazur, P. O.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Mertsch, P.; Meurer, C.; Mićanović, S.; Micheletti, M. I.; Miller, W.; Miramonti, L.; Mollerach, S.; Monasor, M.; Monnier Ragaigne, D.; Montanet, F.; Morales, B.; Morello, C.; Moreno, E.; Moreno, J. C.; Morris, C.; Mostafá, M.; Moura, C. A.; Mueller, S.; Muller, M. A.; Müller, G.; Münchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J. L.; Navas, S.; Necesal, P.; Nellen, L.; Nelles, A.; Nhung, P. T.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nožka, L.; Nyklicek, M.; Oehlschläger, J.; Olinto, A.; Oliva, P.; Olmos-Gilbaja, V. M.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Parrisius, J.; Parsons, R. D.; Pastor, S.; Paul, T.; Pech, M.; PeĶala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrinca, P.; Petrolini, A.; Petrov, Y.; Petrovic, J.; Pfendner, C.; Phan, N.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.; Platino, M.; Ponce, V. H.; Pontz, M.; Privitera, P.; Prouza, M.; Quel, E. J.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Revenu, B.; Ridky, J.; Risse, M.; Ristori, P.; Rivera, H.; Rivière, C.; Rizi, V.; Robledo, C.; Rodrigues de Carvalho, W.; Rodriguez, G.; Rodriguez Martino, J.; Rodriguez Rojo, J.; Rodriguez-Cabo, I.; Rodríguez-Frías, M. D.; Ros, G.; Rosado, J.; Rossler, T.; Roth, M.; Rouillé-D'Orfeuil, B.; Roulet, E.; Rovero, A. C.; Rühle, C.; Salamida, F.; Salazar, H.; Salina, G.; Sánchez, F.; Santander, M.; Santo, C. E.; Santos, E.; Santos, E. M.; Sarazin, F.; Sarkar, S.; Sato, R.; Scharf, N.; Scherini, V.; Schieler, H.; Schiffer, P.; Schmidt, A.; Schmidt, F.; Schmidt, T.; Scholten, O.; Schoorlemmer, H.; Schovancova, J.; Schovánek, P.; Schroeder, F.; Schulte, S.; Schuster, D.; Sciutto, S. J.; Scuderi, M.; Segreto, A.; Semikoz, D.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sidelnik, I.; Sigl, G.; Śmiałkowski, A.; Šmída, R.; Snow, G. R.; Sommers, P.; Sorokin, J.; Spinka, H.; Squartini, R.; Stapleton, J.; Stasielak, J.; Stephan, M.; Stutz, A.; Suarez, F.; Suomijärvi, T.; Supanitsky, A. D.; Šuša, T.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Szuba, M.; Tamashiro, A.; Tapia, A.; Taşcău, O.; Tcaciuc, R.; Tegolo, D.; Thao, N. T.; Thomas, D.; Tiffenberg, J.; Timmermans, C.; Tiwari, D. K.; Tkaczyk, W.; Todero Peixoto, C. J.; Tomé, B.; Tonachini, A.; Travnicek, P.; Tridapalli, D. B.; Tristram, G.; Trovato, E.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van den Berg, A. M.; Vargas Cárdenas, B.; Vázquez, J. R.; Vázquez, R. A.; Veberič, D.; Verzi, V.; Videla, M.; Villaseñor, L.; Wahlberg, H.; Wahrlich, P.; Wainberg, O.; Warner, D.; Watson, A. A.; Weber, M.; Weidenhaupt, K.; Weindl, A.; Westerhoff, S.; Whelan, B. J.; Wieczorek, G.; Wiencke, L.; Wilczyńska, B.; Wilczyński, H.; Will, M.; Williams, C.; Winchen, T.; Winders, L.; Winnick, M. G.; Wommer, M.; Wundheiler, B.; Yamamoto, T.; Younk, P.; Yuan, G.; Zamorano, B.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zaw, I.; Zepeda, A.; Ziolkowski, M.

    2011-03-01

    We present the results of searches for dipolar-type anisotropies in different energy ranges above 2.5 × 1017 eV with the surface detector array of the Pierre Auger Observatory, reporting on both the phase and the amplitude measurements of the first harmonic modulation in the right-ascension distribution. Upper limits on the amplitudes are obtained, which provide the most stringent bounds at present, being below 2% at 99% C.L. for EeV energies. We also compare our results to those of previous experiments as well as with some theoretical expectations.

  13. Optical Manufacturing and Testing Requirements Identified by the NASA Science Instruments, Observatories and Sensor Systems Technology Assessment

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip; Barney, Rich; Bauman, Jill; Feinberg, Lee; Mcleese, Dan; Singh, Upendra

    2011-01-01

    In August 2010, the NASA Office of Chief Technologist (OCT) commissioned an assessment of 15 different technology areas of importance to the future of NASA. Technology assessment #8 (TA8) was Science Instruments, Observatories and Sensor Systems (SIOSS). SIOSS assess the needs for optical technology ranging from detectors to lasers, x-ray mirrors to microwave antenna, in-situ spectrographs for on-surface planetary sample characterization to large space telescopes. The needs assessment looked across the entirety of NASA and not just the Science Mission Directorate. This paper reviews the optical manufacturing and testing technologies identified by SIOSS which require development in order to enable future NASA high priority missions.

  14. Comparison of Martian Surface Radiation Predictions to the Measurements of Mars Science Laboratory Radiation Assessment Detector (MSL/RAD)

    NASA Astrophysics Data System (ADS)

    Kim, M. H. Y.; Cucinotta, F.; Zeitlin, C. J.; Hassler, D.; Ehresmann, B.; Rafkin, S. C.; Wimmer-Schweingruber, R. F.; Böttcher, S. I.; Boehm, E.; Guo, J.; Kohler, J.; Martin-Garcia, C.; Reitz, G.; Posner, A.

    2014-12-01

    For the analysis of radiation risks to astronauts and planning exploratory space missions, detailed knowledge of particle spectra is an important factor. Detailed measurements of the energetic particle radiation environment on the surface of Mars have been made by the Mars Science Laboratory Radiation Assessment Detector (MSL-RAD) on the Curiosity rover since August 2012, and particle fluxes for a wide range of ion species (up to several hundred MeV/u) and high energy neutrons (8 - 1000 MeV) have been available for the first 200 sols. Although the data obtained on the surface of Mars for 200 sols are limited in the narrow energy spectra, the simulation results using the Badhwar-O'Neill galactic cosmic ray (GCR) environment model and the high-charge and energy transport (HZETRN) code are compared to the data. For the nuclear interactions of primary GCR through Mars atmosphere and Curiosity rover, the quantum multiple scattering theory of nuclear fragmentation (QMSFRG) is used, which includes direct knockout, evaporation and nuclear coalescence. Daily atmospheric pressure measurements at Gale Crater by the MSL Rover Environmental Monitoring Station are implemented into transport calculations for describing the daily column depth of atmosphere. Particles impinging on top of the Martian atmosphere reach the RAD after traversing varying depths of atmosphere that depend on the slant angles, and the model accounts for shielding of the RAD by the rest of the instrument. Calculations of stopping particle spectra are in good agreement with the RAD measurements for the first 200 sols by accounting changing heliospheric conditions and atmospheric pressure. Detailed comparisons between model predictions and spectral data of various particle types provide the validation of radiation transport models, and thus increase the accuracy of the predictions of future radiation environments on Mars. These contributions lend support to the understanding of radiation health risks to

  15. Comparison of Martian Surface Radiation Predictions to the Measurements of Mars Science Laboratory Radiation Assessment Detector (MSL/RAD)

    NASA Technical Reports Server (NTRS)

    Kim, Myung-Hee Y.; Cucinotta, Francis A.; Zeitlin, Cary; Hassler, Donald M.; Ehresmann, Bent; Rafkin, Scot C. R.; Wimmer-Schweingruber, Robert F; Boettcher, Stephan; Boehm, Eckart; Guo, Jingnan; Koehler, Jan; Martin, Cesar; Reitz, Guenther; Posner, Erik

    2014-01-01

    For the analysis of radiation risks to astronauts and planning exploratory space missions, detailed knowledge of particle spectra is an important factor. Detailed measurements of the energetic particle radiation environment on the surface of Mars have been made by the Mars Science Laboratory Radiation Assessment Detector (MSL-RAD) on the Curiosity rover since August 2012, and particle fluxes for a wide range of ion species (up to several hundred MeV/u) and high energy neutrons (8 - 1000 MeV) have been available for the first 200 sols. Although the data obtained on the surface of Mars for 200 sols are limited in the narrow energy spectra, the simulation results using the Badhwar-O'Neill galactic cosmic ray (GCR) environment model and the high-charge and energy transport (HZETRN) code are compared to the data. For the nuclear interactions of primary GCR through Mars atmosphere and Curiosity rover, the quantum multiple scattering theory of nuclear fragmentation (QMSFRG) is used, which includes direct knockout, evaporation and nuclear coalescence. Daily atmospheric pressure measurements at Gale Crater by the MSL Rover Environmental Monitoring Station are implemented into transport calculations for describing the daily column depth of atmosphere. Particles impinging on top of the Martian atmosphere reach the RAD after traversing varying depths of atmosphere that depend on the slant angles, and the model accounts for shielding of the RAD by the rest of the instrument. Calculations of stopping particle spectra are in good agreement with the RAD measurements for the first 200 sols by accounting changing heliospheric conditions and atmospheric pressure. Detailed comparisons between model predictions and spectral data of various particle types provide the validation of radiation transport models, and thus increase the accuracy of the predictions of future radiation environments on Mars. These contributions lend support to the understanding of radiation health risks to

  16. Upgrade of the Central Laser Facility at the Pierre Auger Observatory and first results

    NASA Astrophysics Data System (ADS)

    Medina-Hernandez, Carlos; Wiencke, Lawrence; Mayotte, Eric; Pierre Auger Collaboration

    2015-04-01

    The Pierre Auger Observatory (PAO) explores the nature and origin of cosmic rays with energies above 1018 eV. It uses a hybrid technique that combines a Fluorescence Detector (FD) and a 3000 Km2 surface Detector (SD) array. Two laser test beam facilities are located near the center of the observatory. The Central Laser Facility (CLF) and the eXtreme Laser Facility (XLF) track the atmospheric conditions during FD's operations and perform additional functions. The CLF was upgraded substantially in 2013 with a solid state laser, new generation GPS, robotic beam calibration system, and better thermal and dust isolation. The upgrade also includes a back scatter Raman Lidar receiver, providing an independent measurement the aerosol optical depth (tau(z,t)). We describe the new features, capabilities, and applications of the updated instrument, including, tau(z,t) calculations for atmospheric monitoring using a data normalized method, laser energy calibration, and steered laser firing for arrival directions studies. We also present the first tau(z,t) results after the upgrade,using two using two independent techniques. One method uses the FD's measurements of the CLF's laser shots in bi-static configuration. The other uses the Raman LIDAR in back scattered configuration.

  17. High Energy Astronomy Observatory (HEAO)-2

    NASA Technical Reports Server (NTRS)

    1975-01-01

    This illustration is a schematic of the High Energy Astronomy Observatory (HEAO)-2 and its experiments. It shows the focal plane instruments (at the right) plus the associated electronics for operating the telescope as it transmitted its observations to the ground. A fifth instrument, the Monitor Proportional Counter, is located near the front of the telescope. Four separate astronomical instruments are located at the focus of this telescope and they could be interchanged for different types of observations as the observatory pointed at interesting areas of the Sky. Two of these instruments produced images; a High Resolution Imaging Detector and an Imaging Proportional Counter. The other two instruments, the Solid State Spectrometer and the Crystal Spectrometer, measured the spectra of x-ray objects. A fifth instrument, the Monitor Proportional Counter, continuously viewed space independently to study a wider band of x-ray wavelengths and to examine the rapid time variations in the sources. The HEAO-2 was nicknamed the Einstein Observatory by its scientific experimenters in honor of the centernial of the birth of Albert Einstein, whose concepts of relativity and gravitation have influenced much of modern astrophysics, particularly x-ray astronomy. The HEAO-2, designed and developed by TRW, Inc. under the project management of the Marshall Space Flight Center, was launched aboard an Atlas/Centaur launch vehicle on November 13, 1978. The HEAO-2 was originally identified as HEAO-B but the designation was changed once the spacecraft achieved orbit.

  18. Astronomical publications of Melbourne Observatory

    NASA Astrophysics Data System (ADS)

    Andropoulos, Jenny Ioanna

    2014-05-01

    During the second half of the 19th century and the first half of the 20th century, four well-equipped government observatories were maintained in Australia - in Melbourne, Sydney, Adelaide and Perth. These institutions conducted astronomical observations, often in the course of providing a local time service, and they also collected and collated meteorological data. As well, some of these observatories were involved at times in geodetic surveying, geomagnetic recording, gravity measurements, seismology, tide recording and physical standards, so the term "observatory" was being used in a rather broad sense! Despite the international renown that once applied to Williamstown and Melbourne Observatories, relatively little has been written by modern-day scholars about astronomical activities at these observatories. This research is intended to rectify this situation to some extent by gathering, cataloguing and analysing the published astronomical output of the two Observatories to see what contributions they made to science and society. It also compares their contributions with those of Sydney, Adelaide and Perth Observatories. Overall, Williamstown and Melbourne Observatories produced a prodigious amount of material on astronomy in scientific and technical journals, in reports and in newspapers. The other observatories more or less did likewise, so no observatory of those studied markedly outperformed the others in the long term, especially when account is taken of their relative resourcing in staff and equipment.

  19. Distributed Observatory Management

    NASA Astrophysics Data System (ADS)

    Godin, M. A.; Bellingham, J. G.

    2006-12-01

    A collection of tools for collaboratively managing a coastal ocean observatory have been developed and used in a multi-institutional, interdisciplinary field experiment. The Autonomous Ocean Sampling Network program created these tools to support the Adaptive Sampling and Prediction (ASAP) field experiment that occurred in Monterey Bay in the summer of 2006. ASAP involved the day-to-day participation of a large group of researchers located across North America. The goal of these investigators was to adapt an array of observational assets to optimize data collection and analysis. Achieving the goal required continual interaction, but the long duration of the observatory made sustained co-location of researchers difficult. The ASAP team needed a remote collaboration tool, the capability to add non-standard, interdisciplinary data sets to the overall data collection, and the ability to retrieve standardized data sets from the collection. Over the course of several months and "virtual experiments," the Ocean Observatory Portal (COOP) collaboration tool was created, along with tools for centralizing, cataloging, and converting data sets into common formats, and tools for generating automated plots of the common format data. Accumulating the data in a central location and converting the data to common formats allowed any team member to manipulate any data set quickly, without having to rely heavily on the expertise of data generators to read the data. The common data collection allowed for the development of a wide range of comparison plots and allowed team members to assimilate new data sources into derived outputs such as ocean models quickly. In addition to the standardized outputs, team members were able to produce their own specialized products and link to these through the collaborative portal, which made the experimental process more interdisciplinary and interactive. COOP was used to manage the ASAP vehicle program from its start in July 2006. New summaries were

  20. Next Generation Virtual Observatories

    NASA Astrophysics Data System (ADS)

    Fox, P.; McGuinness, D. L.

    2008-12-01

    Virtual Observatories (VO) are now being established in a variety of geoscience disciplines beyond their origins in Astronomy and Solar Physics. Implementations range from hydrology and environmental sciences to solid earth sciences. Among the goals of VOs are to provide search/ query, access and use of distributed, heterogeneous data resources. With many of these goals being met and usage increasing, new demands and requirements are arising. In particular there are two of immediate and pressing interest. The first is use of VOs by non-specialists, especially for information products that go beyond the usual data, or data products that are sought for scientific research. The second area is citation and attribution of artifacts that are being generated by VOs. In some sense VOs are re-publishing (re-packaging, or generating new synthetic) data and information products. At present only a few VOs address this need and it is clear that a comprehensive solution that includes publishers is required. Our work in VOs and related semantic data framework and integration areas has lead to a view of the next generation of virtual observatories which the two above-mentioned needs as well as others that are emerging. Both of the needs highlight a semantic gap, i.e. that the meaning and use for a user or users beyond the original design intention is very often difficult or impossible to bridge. For example, VOs created for experts with complex, arcane or jargon vocabularies are not accessible to the non-specialist and further, information products the non-specialist may use are not created or considered for creation. In the second case, use of a (possibly virtual) data or information product (e.g. an image or map) as an intellectual artifact that can be accessed as part of the scientific publication and review procedure also introduces terminology gaps, as well as services that VOs may need to provide. Our supposition is that formalized methods in semantics and semantic web

  1. Strasbourg Observatory Archives Revisited

    NASA Astrophysics Data System (ADS)

    Heck, A.

    2002-12-01

    Official talks in France and Germany after World War I were generally of hatred and revenge. Strasbourg Observatory had just changed nationality (from Prussian to French) for the first time (this would happen again at the outbreak of WWII and after the conflict). Documents show that astronomers did not share the general attitude. For example the inventory book started in German was continued in French after 1918. It is moving to see those different handwritings in two different languages on the same pages -- making of that book a unique document in various respects, but also reminding us that the native language of the region was in fact Alsacian.

  2. NASA's Heliophysics System Observatory

    NASA Astrophysics Data System (ADS)

    Clarke, Steven

    2016-04-01

    NASA formulates and implements a national research program for understanding the Sun and its interactions with the Earth and the solar system and how these phenomena impact life and society. This research provides theory, data, and modeling development services to national and international space weather efforts utilizing a coordinated and complementary fleet of spacecraft, called the Heliophysics System Observatory (HSO), to understand the Sun and its interactions with Earth and the solar system, including space weather. This presentation will focus on NASA's role in space weather research and the contributions the agency continues to provide to the science of space weather, leveraging inter-agency and international collaborations for the benefit of society.

  3. Investigation of crystal surface finish and geometry on single LYSO scintillator detector performance for depth-of-interaction measurement with silicon photomultipliers

    NASA Astrophysics Data System (ADS)

    Bircher, Chad; Shao, Yiping

    2012-11-01

    Depth of Interaction (DOI) information can improve quality of reconstructed images acquired from Positron Emission Tomography (PET), especially in high resolution and compact scanners dedicated for breast, brain, or small animal imaging applications. Additionally, clinical scanners with time of flight capability can also benefit from DOI information. One of the most promising methods of determining DOI in a crystal involves reading the signal from two ends of a scintillation crystal, and calculating the signal ratio between the two detectors. This method is known to deliver a better DOI resolution with rough crystals compared to highly polished crystals. However, what is still not well studied is how much of a tradeoff is involved between spatial, energy, temporal, and DOI resolutions as a function of the crystal surface treatment and geometry with the use of Silicon Photomultipliers (SiPM) as the photo detectors. This study investigates the effects of different crystal surface finishes and geometries on energy, timing and DOI resolutions at different crystal depths. The results show that for LYSO scintillators of 1.5×1.5×20 mm3 and 2×2×20 mm3 with their surfaces finished from 0.5 to 30 μm roughness, almost the same energy and coincidence timing resolutions were maintained, around 15% and 2.4 ns, respectively across different crystal depths, while the DOI resolutions were steadily improved from worse than 5 mm to better than 2 mm. They demonstrate that crystal roughness, with proper surface preparing, does not have a significant effect on the energy and coincidence timing resolutions in the crystals examined, and there does not appear to be a tradeoff between improving DOI resolution and degrading other detector performances. These results will be valuable to guide the selection of crystal surface conditions for developing a DOI measurable PET detector with a full array of LYSO scintillators coupled to SiPM arrays.

  4. Moon exploration: lunar radio observatory

    NASA Astrophysics Data System (ADS)

    Skalsky, Alexandre; Zelenyi, Lev; Rothkaehl, Hanna; Gurvits, Leonid; Sadovski, Andrei; Mogilevsky, Mikhail; Gotlib, Vladimir

    The Moon is an attractive base for fundamental scientific studies. The conducting ionosphere of Earth prevents propagation of radio emission coming from the outer space to the Earth’s surface at frequencies below a few MHz. In contrast, the Moon surrounded by a very thin atmosphere and ionosphere is a perfect site for an ultra-long-wavelength (ULW) facility for studies of cosmic radio emission at frequencies below the Earth’s ionosphere cut-off. This range of frequencies is the last unexplored window in the spectrum of the universe’s electromagnetic emission, The radio facility deployed on the Moon’s surface will be a multidisciplinary tool for addressing a wide range of scientific disciplines from cosmology to astrophysics to planetology, solar-terrestrial physics and geophysics. The Moon-based ULW observatory will be an experimental and observational facility for transformational science. One of the most intriguing objectives for the ULW science is a search for terrestrial-like planets in the exosolar systems, i.e. extra-solar planets possessing an intrinsic magnetic field and magnetospheres interacting with a stellar wind. Such the interaction generates radio emission similar to the Auroral Kilometric Radiation (AKR) of the terrestrial magnetosphere. The intrinsic magnetic field shielding the planetary surface from the cosmic radiation is one of the strong indicators of possible habitability of an exoplanet. ACKNOWLEDGMENTS: This work was supported by the PP RAS 22 grant.

  5. Virtual Energetic Particle Observatory (VEPO)

    NASA Astrophysics Data System (ADS)

    Cooper, J. F.; Lal, N.; McGuire, R. E.; Szabo, A.; Narock, T. W.; Armstrong, T. P.; Manweiler, J. W.; Patterson, J. D.; Hill, M. E.; Vandergriff, J. D.; McKibben, R. B.; Lopate, C.; Tranquille, C.

    2008-12-01

    The Virtual Energetic Particle Observatory (VEPO) focuses on improved discovery, access, and usability of heliospheric energetic particle and ancillary data products from selected spacecraft and sub-orbital instruments of the heliophysics data environment. The energy range of interest extends over the full range of particle acceleration from keV energies of suprathermal seed particles to GeV energies of galactic cosmic ray particles. Present spatial coverage is for operational and legacy spacecraft operating from the inner to the outer heliosphere, e.g. from measurements by the two Helios spacecraft to 0.3 AU to the inner heliosheath region now being traversed by the two Voyager spacecraft. This coverage will eventually be extended inward to ten solar radii by the planned NASA solar probe mission and at the same time beyond the heliopause into the outer heliosheath by continued Voyager operations. The geospace fleet of spacecraft providing near-Earth interplanetary measurements, selected magnetospheric spacecraft providing direct measurements of penetrating interplanetary energetic particles, and interplanetary cruise measurements from planetary spacecraft missions further extend VEPO resources to the domain of geospace and planetary interactions. Ground-based (e.g., neutron monitor) and high-altitude suborbital measurements can expand coverage to the highest energies of galactic cosmic rays affected by heliospheric interaction and of solar energetic particles. Science applications include investigation of solar flare and coronal mass ejection events, acceleration and transport of interplanetary particles within the inner heliosphere, cosmic ray interactions with planetary surfaces and atmospheres, sources of suprathermal and anomalous cosmic ray ions in the outer heliosphere, and solar cycle modulation of galactic cosmic rays. Robotic and human exploration, and eventual habitation, of planetary and space environments beyond the Earth require knowledge of radiation

  6. Virtual Energetic Particle Observatory (VEPO)

    NASA Technical Reports Server (NTRS)

    Cooper, John F.; Lal, Nand; McGuire, Robert E.; Szabo, Adam; Narock, Thomas W.; Armstrong, Thomas P.; Manweiler, Jerry W.; Patterson, J. Douglas; Hill, Matthew E.; Vandergriff, Jon D.; McKibben, Robert B.; Lopate, Clifford; Tranquille, Cecil

    2008-01-01

    The Virtual Energetic Particle Observatory (VEPO) focuses on improved discovery, access, and usability of heliospheric energetic particle and ancillary data products from selected spacecraft and sub-orbital instruments of the heliophysics data environment. The energy range of interest extends over the full range of particle acceleration from keV energies of suprathermal seed particles to GeV energies of galactic cosmic ray particles. Present spatial coverage is for operational and legacy spacecraft operating from the inner to the outer heliosphere, e.g. from measurements by the two Helios spacecraft to 0.3 AU to the inner heliosheath region now being traversed by the two Voyager spacecraft. This coverage will eventually be extended inward to ten solar radii by the planned NASA solar probe mission and at the same time beyond the heliopause into the outer heliosheath by continued Voyager operations. The geospace fleet of spacecraft providing near-Earth interplanetary measurements, selected magnetospheric spacecraft providing direct measurements of penetrating interplanetary energetic particles, and interplanetary cruise measurements from planetary spacecraft missions further extend VEPO resources to the domain of geospace and planetary interactions. Ground-based (e.g., neutron monitor) and high-altitude suborbital measurements can expand coverage to the highest energies of galactic cosmic rays affected by heliospheric interaction and of solar energetic particles. Science applications include investigation of solar flare and coronal mass ejection events. acceleration and transport of interplanetary particles within the inner heliosphere, cosmic ray interactions with planetary surfaces and atmospheres, sources of suprathermal and anomalous cosmic ray ions in the outer heliosphere, and solar cycle modulation of galactic cosmic rays. Robotic and human exploration, and eventual habitation, of planetary and space environments beyond the Earth require knowledge of radiation

  7. Production of mineral surface area within deep weathering profiles at eroding vs. depositional hillslope locations: Christina River Basin Critical Zone Observatory

    NASA Astrophysics Data System (ADS)

    Fisher, B.; Yoo, K.; Aufdenkampe, A. K.; Nater, E.

    2014-12-01

    Geomorphic and biogeochemical processes and hillslope morphology are partly controlled by the extent and degree of chemical weathering between soil and bedrock. The production of mineral specific surface area (SSA) via chemical weathering is a critical variable for mechanistic understanding of weathering and provides an interface between minerals and the soil carbon cycle. We examined two 21-meter deep drill cores in the Laurels Schist at 141 MASL (summit) and 130 MASL (interfluve) in a 900 ha first order watershed in the Laurels Preserve, a forested land use end member in the Christina River Basin CZO. In addition to mineral SSA, we report elemental and mineralogical changes through both weathering profiles. Despite highly variable bedrock composition, mobile elements (Ca & Na) are depleted within 3-5 m below the ground surface, which is consistent with the removal of Ca-Na-plagioclase ((Na,Ca)Al(Si,Al)3O8) at this interval; we consider this depth as a weathering front. The water table in both boreholes was ~123 MASL (5/2014), which is well below the weathering front, suggesting that weathering processes are not coupled with groundwater interactions in this system. Clay XRD reveals the presence of secondary phyllosilicates including vermiculite, illite, and kaolinite in the upper 3 m of the summit weathering profile, which are weathering products of primary plagioclase, muscovite, and chlorite. The currently available clay mineralogy results are consistent with the decrease in total SSA from up to 20 m2g-1 at the surface to <5 m2g-1 below 3 m depth. Within the first 3 m from the surface, citrate-dithionate extractable iron contributed 30-60% of the total surface area. Therefore transformation of primary minerals to secondary phyllosilicate minerals, involving leaching loss of cations, was partly responsible for SSA production, but iron oxides play a significant role in production of SSA above the weathering front. This observation did not differ between

  8. Byurakan Astrophysical Observatory

    NASA Astrophysics Data System (ADS)

    Mickaelian, A. M.

    2016-09-01

    This booklet is devoted to NAS RA V. Ambartsumian Byurakan Astrophysical Observatory and is aimed at people interested in astronomy and BAO, pupils and students, BAO visitors and others. The booklet is made as a visiting card and presents concise and full information about BAO. A brief history of BAO, the biography of the great scientist Viktor Ambartsumian, brief biographies of 13 other deserved scientists formerly working at BAO (B.E. Markarian, G.A. Gurzadyan, L.V. Mirzoyan, M.A. Arakelian, et al.), information on BAO telescopes (2.6m, 1m Schmidt, etc.) and other scientific instruments, scientific library and photographic plate archive, Byurakan surveys (including the famous Markarian Survey included in the UNESCO Memory of the World International Register), all scientific meetings held in Byurakan, international scientific collaboration, data on full research staff of the Observatory, as well as former BAO researchers, who have moved to foreign institutions are given in the booklet. At the end, the list of the most important books published by Armenian astronomers and about them is given.

  9. MEMS infrared approaches to detector based on nonlinear oscillation and wavelength selective emitter using surface plasmon polariton

    NASA Astrophysics Data System (ADS)

    Sasaki, Minoru; Kumagai, Shinya

    2014-03-01

    The suspended MEMS structure is suitable for reducing the energy loss due to the thermal conduction. There is the possibility that IR photon energy can be well-controlled to generate some physical effects. A new method bases on the nonlinear oscillation for the detector. The thin film torsional spring exhibits a large hard spring effect when the deflection occurs in the out-of-plane direction of the film. When IR is absorbed, the resonator bends due to the thermal expansion. The torsional spring becomes harder increasing the resonant frequency. The frequency measurement is suited for the precise sensing. The device response is measured using the laser (wavelength of 650nm). The resonant frequency is 88-94kHz. Q factor is about 1600 in vacuum (1Pa). The sensitivity is -0.144[kHz/(kW/m2)]. As for the emitter, nondispersive IR gas sensor is considered. The molecules have their intrinsic absorptions. CO2 absorbs the wavelength 4.2- 4.3μm. The major incandescent light bulbs have the broad spectrum emitting IR which is not used for gas sensing. The wavelength selectivity at the gas bandwidth will improve the efficiency. A new principle uses the microheater placed facing to the grating. SPP is excited carrying IR energy on the grating surface. IR emission is the reverse process of excitation occurring at the output end. The emission spectra show SPP related peak having the width of 190nm. When the input power increases from 0.3 to 1.9W, the peak at wavelength of 3.5μm becomes clearer.

  10. Muons in air showers at the Pierre Auger Observatory: Mean number in highly inclined events

    NASA Astrophysics Data System (ADS)

    Aab, A.; Abreu, P.; Aglietta, M.; Ahn, E. J.; Al Samarai, I.; Albuquerque, I. F. M.; Allekotte, I.; Allen, J.; Allison, P.; Almela, A.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Alves Batista, R.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Aramo, C.; Aranda, V. M.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Badescu, A. M.; Barber, K. B.; Bäuml, J.; Baus, C.; Beatty, J. J.; Becker, K. H.; Bellido, J. A.; Berat, C.; Bertaina, M. E.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, M.; Bleve, C.; Blümer, H.; Boháčová, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brancus, I.; Brogueira, P.; Brown, W. C.; Buchholz, P.; Bueno, A.; Buitink, S.; Buscemi, M.; Caballero-Mora, K. S.; Caccianiga, B.; Caccianiga, L.; Candusso, M.; Caramete, L.; Caruso, R.; Castellina, A.; Cataldi, G.; Cazon, L.; Cester, R.; Chavez, A. G.; Chiavassa, A.; Chinellato, J. A.; Chudoba, J.; Cilmo, M.; Clay, R. W.; Cocciolo, G.; Colalillo, R.; Coleman, A.; Collica, L.; Coluccia, M. R.; Conceição, R.; Contreras, F.; Cooper, M. J.; Cordier, A.; Coutu, S.; Covault, C. E.; Cronin, J.; Curutiu, A.; Dallier, R.; Daniel, B.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; De Domenico, M.; de Jong, S. J.; de Mello Neto, J. R. T.; De Mitri, I.; de Oliveira, J.; de Souza, V.; del Peral, L.; Deligny, O.; Dembinski, H.; Dhital, N.; Di Giulio, C.; Di Matteo, A.; Diaz, J. C.; Díaz Castro, M. L.; Diogo, F.; Dobrigkeit, C.; Docters, W.; D'Olivo, J. C.; Dorofeev, A.; Dorosti Hasankiadeh, Q.; Dova, M. T.; Ebr, J.; Engel, R.; Erdmann, M.; Erfani, M.; Escobar, C. O.; Espadanal, J.; Etchegoyen, A.; Facal San Luis, P.; Falcke, H.; Fang, K.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Fernandes, M.; Fick, B.; Figueira, J. M.; Filevich, A.; Filipčič, A.; Fox, B. D.; Fratu, O.; Fröhlich, U.; Fuchs, B.; Fujii, T.; Gaior, R.; García, B.; Garcia Roca, S. T.; Garcia-Gamez, D.; Garcia-Pinto, D.; Garilli, G.; Gascon Bravo, A.; Gate, F.; Gemmeke, H.; Ghia, P. L.; Giaccari, U.; Giammarchi, M.; Giller, M.; Glaser, C.; Glass, H.; Gómez Berisso, M.; Gómez Vitale, P. F.; Gonçalves, P.; Gonzalez, J. G.; González, N.; Gookin, B.; Gordon, J.; Gorgi, A.; Gorham, P.; Gouffon, P.; Grebe, S.; Griffith, N.; Grillo, A. F.; Grubb, T. D.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Hampel, M. R.; Hansen, P.; Harari, D.; Harrison, T. A.; Hartmann, S.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Heimann, P.; Herve, A. E.; Hill, G. C.; Hojvat, C.; Hollon, N.; Holt, E.; Homola, P.; Hörandel, J. R.; Horvath, P.; Hrabovský, M.; Huber, D.; Huege, T.; Insolia, A.; Isar, P. G.; Islo, K.; Jandt, I.; Jansen, S.; Jarne, C.; Josebachuili, M.; Kääpä, A.; Kambeitz, O.; Kampert, K. H.; Kasper, P.; Katkov, I.; Kégl, B.; Keilhauer, B.; Keivani, A.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Krause, R.; Krohm, N.; Krömer, O.; Kruppke-Hansen, D.; Kuempel, D.; Kunka, N.; LaHurd, D.; Latronico, L.; Lauer, R.; Lauscher, M.; Lautridou, P.; Le Coz, S.; Leão, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; López, R.; Louedec, K.; Lozano Bahilo, J.; Lu, L.; Lucero, A.; Ludwig, M.; Malacari, M.; Maldera, S.; Mallamaci, M.; Maller, J.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, V.; Mariş, I. C.; Marsella, G.; Martello, D.; Martin, L.; Martinez, H.; Martínez Bravo, O.; Martraire, D.; Masías Meza, J. J.; Mathes, H. J.; Mathys, S.; Matthews, J. J.; Matthews, A. J.; Matthiae, G.; Maurel, D.; Maurizio, D.; Mayotte, E.; Mazur, P. O.; Medina, C.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menshikov, A.; Messina, S.; Meyhandan, R.; Mićanović, S.; Micheletti, M. I.; Middendorf, L.; Minaya, I. A.; Miramonti, L.; Mitrica, B.; Molina-Bueno, L.; Mollerach, S.; Monasor, M.; Monnier Ragaigne, D.; Montanet, F.; Morello, C.; Mostafá, M.; Moura, C. A.; Muller, M. A.; Müller, G.; Münchmeyer, M.; Mussa, R.; Navarra, G.; Navas, S.; Necesal, P.; Nellen, L.; Nelles, A.; Neuser, J.; Newton, D.; Niechciol, M.; Niemietz, L.; Niggemann, T.; Nitz, D.; Nosek, D.; Novotny, V.; Nožka, L.; Ochilo, L.; Olinto, A.; Oliveira, M.; Olmos-Gilbaja, V. M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Papenbreer, P.; Parente, G.; Parra, A.; Paul, T.; Pech, M.; Pekala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Petermann, E.; Peters, C.; Petrera, S.; Petrov, Y.; Phuntsok, J.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.; Platino, M.; Plum, M.; Porcelli, A.; Porowski, C.; Prado, R. R.; Privitera, P.; Prouza, M.; Purrello, V.; Quel, E. J.; Querchfeld, S.; Quinn, S.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Revenu, B.; Ridky, J.; Riggi, S.; Risse, M.; Ristori, P.; Rizi, V.; Roberts, J.; Rodrigues de Carvalho, W.; Rodriguez Fernandez, G.; Rodriguez Rojo, J.; Rodríguez-Frías, M. D.; Ros, G.; Rosado, J.; Rossler, T.; Roth, M.; Roulet, E.; Rovero, A. C.; Saffi, S. J.; Saftoiu, A.; Salamida, F.; Salazar, H.; Saleh, A.; Salesa Greus, F.; Salina, G.; Sánchez, F.; Sanchez-Lucas, P.; Santo, C. E.; Santos, E.; Santos, E. M.; Sarazin, F.; Sarkar, B.; Sarmento, R.; Sato, R.; Scharf, N.; Scherini, V.; Schieler, H.; Schiffer, P.; Scholten, O.; Schoorlemmer, H.; Schovánek, P.; Schröder, F. G.; Schulz, A.; Schulz, J.; Schumacher, J.; Sciutto, S. J.; Segreto, A.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sidelnik, I.; Sigl, G.; Sima, O.; Śmiałkowski, A.; Šmída, R.; Snow, G. R.; Sommers, P.; Sorokin, J.; Squartini, R.; Srivastava, Y. N.; Stanič, S.; Stapleton, J.; Stasielak, J.; Stephan, M.; Stutz, A.; Suarez, F.; Suomijärvi, T.; Supanitsky, A. D.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Szuba, M.; Taborda, O. A.; Tapia, A.; Tartare, M.; Tepe, A.; Theodoro, V. M.; Timmermans, C.; Todero Peixoto, C. J.; Toma, G.; Tomankova, L.; Tomé, B.; Tonachini, A.; Torralba Elipe, G.; Torres Machado, D.; Travnicek, P.; Trovato, E.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van Aar, G.; van den Berg, A. M.; van Velzen, S.; van Vliet, A.; Varela, E.; Vargas Cárdenas, B.; Varner, G.; Vázquez, J. R.; Vázquez, R. A.; Veberič, D.; Verzi, V.; Vicha, J.; Videla, M.; Villaseñor, L.; Vlcek, B.; Vorobiov, S.; Wahlberg, H.; Wainberg, O.; Walz, D.; Watson, A. A.; Weber, M.; Weidenhaupt, K.; Weindl, A.; Werner, F.; Widom, A.; Wiencke, L.; Wilczyńska, B.; Wilczyński, H.; Will, M.; Williams, C.; Winchen, T.; Wittkowski, D.; Wundheiler, B.; Wykes, S.; Yamamoto, T.; Yapici, T.; Younk, P.; Yuan, G.; Yushkov, A.; Zamorano, B.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zaw, I.; Zepeda, A.; Zhou, J.; Zhu, Y.; Zimbres Silva, M.; Ziolkowski, M.; Zuccarello, F.; Pierre Auger Collaboration

    2015-02-01

    We present the first hybrid measurement of the average muon number in air showers at ultrahigh energies, initiated by cosmic rays with zenith angles between 62° and 80°. The measurement is based on 174 hybrid events recorded simultaneously with the surface detector array and the fluorescence detector of the Pierre Auger Observatory. The muon number for each shower is derived by scaling a simulated reference profile of the lateral muon density distribution at the ground until it fits the data. A 1019 eV shower with a zenith angle of 67°, which arrives at the surface detector array at an altitude of 1450 m above sea level, contains on average (2.68 ±0.04 ±0.48 (sys))×107 muons with energies larger than 0.3 GeV. The logarithmic gain d ln Nμ/d ln E of muons with increasing energy between 4 ×1018 eV and 5 ×1019 eV is measured to be (1.029 ±0.024 ±0.030 (sys)) .

  11. Advanced functionality for radio analysis in the Offline software framework of the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Abreu, P.; Aglietta, M.; Ahn, E. J.; Albuquerque, I. F. M.; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Antičić, T.; Aramo, C.; Arganda, E.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Bäcker, T.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Beatty, J. J.; Becker, B. R.; Becker, K. H.; Bellido, J. A.; Benzvi, S.; Berat, C.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Blümer, H.; Boháčová, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brogueira, P.; Brown, W. C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Burton, R. E.; Caballero-Mora, K. S.; Caramete, L.; Caruso, R.; Castellina, A.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Chiavassa, A.; Chinellato, J. A.; Chou, A.; Chudoba, J.; Clay, R. W.; Coluccia, M. R.; Conceição, R.; Contreras, F.; Cook, H.; Cooper, M. J.; Coppens, J.; Cordier, A.; Cotti, U.; Coutu, S.; Covault, C. E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; de Domenico, M.; de Donato, C.; de Jong, S. J.; de La Vega, G.; de Mello Junior, W. J. M.; de Mello Neto, J. R. T.; de Mitri, I.; de Souza, V.; de Vries, K. D.; Decerprit, G.; Del Peral, L.; Deligny, O.; Dembinski, H.; Denkiewicz, A.; di Giulio, C.; Diaz, J. C.; Díaz Castro, M. L.; Diep, P. N.; Dobrigkeit, C.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; Dos Anjos, J. C.; Dova, M. T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C. O.; Etchegoyen, A.; Facal San Luis, P.; Falcke, H.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Ferrero, A.; Fick, B.; Filevich, A.; Filipčič, A.; Fliescher, S.; Fracchiolla, C. E.; Fraenkel, E. D.; Fröhlich, U.; Fuchs, B.; Gamarra, R. F.; Gambetta, S.; García, B.; García Gámez, D.; Garcia-Pinto, D.; Gascon, A.; Gemmeke, H.; Gesterling, K.; Ghia, P. L.; Giaccari, U.; Giller, M.; Glass, H.; Gold, M. S.; Golup, G.; Gomez Albarracin, F.; Gómez Berisso, M.; Gonçalves, P.; Gonzalez, D.; Gonzalez, J. G.; Gookin, B.; Góra, D.; Gorgi, A.; Gouffon, P.; Gozzini, S. R.; Grashorn, E.; Grebe, S.; Griffith, N.; Grigat, M.; Grillo, A. F.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Hague, J. D.; Hansen, P.; Harari, D.; Harmsma, S.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A. E.; Hojvat, C.; Holmes, V. C.; Homola, P.; Hörandel, J. R.; Horneffer, A.; Hrabovský, M.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jiraskova, S.; Kadija, K.; Kampert, K. H.; Karhan, P.; Karova, T.; Kasper, P.; Kégl, B.; Keilhauer, B.; Keivani, A.; Kelley, J. L.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D.-H.; Kotera, K.; Krohm, N.; Krömer, O.; Kruppke-Hansen, D.; Kuehn, F.; Kuempel, D.; Kulbartz, J. K.; Kunka, N.; La Rosa, G.; Lachaud, C.; Lautridou, P.; Leão, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Lemiere, A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; López, R.; Lopez Agüera, A.; Louedec, K.; Lozano Bahilo, J.; Lucero, A.; Ludwig, M.; Lyberis, H.; Macolino, C.; Maldera, S.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, V.; Maris, I. C.; Marquez Falcon, H. R.; Marsella, G.; Martello, D.; Martin, L.; Martínez Bravo, O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mazur, P. O.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Mertsch, P.; Meurer, C.; Mićanović, S.; Micheletti, M. I.; Miller, W.; Miramonti, L.; Mollerach, S.; Monasor, M.; Monnier Ragaigne, D.; Montanet, F.; Morales, B.; Morello, C.; Moreno, E.; Moreno, J. C.; Morris, C.; Mostafá, M.; Moura, C. A.; Mueller, S.; Muller, M. A.; Müller, G.; Münchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J. L.; Navas, S.; Necesal, P.; Nellen, L.; Nelles, A.; Nhung, P. T.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nožka, L.; Nyklicek, M.; Oehlschläger, J.; Olinto, A.; Oliva, P.; Olmos-Gilbaja, V. M.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Parrisius, J.; Parsons, R. D.; Pastor, S.; Paul, T.; Pech, M.; PeĶala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrinca, P.; Petrolini, A.; Petrov, Y.; Petrovic, J.; Pfendner, C.; Phan, N.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.; Platino, M.; Ponce, V. H.; Pontz, M.; Privitera, P.; Prouza, M.; Quel, E. J.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Revenu, B.; Ridky, J.; Risse, M.; Ristori, P.; Rivera, H.; Riviére, C.; Rizi, V.; Robledo, C.; Rodrigues de Carvalho, W.; Rodriguez, G.; Rodriguez Martino, J.; Rodriguez Rojo, J.; Rodriguez-Cabo, I.; Rodríguez-Frías, M. D.; Ros, G.; Rosado, J.; Rossler, T.; Roth, M.; Rouillé-D'Orfeuil, B.; Roulet, E.; Rovero, A. C.; Rühle, C.; Salamida, F.; Salazar, H.; Salina, G.; Sánchez, F.; Santander, M.; Santo, C. E.; Santos, E.; Santos, E. M.; Sarazin, F.; Sarkar, S.; Sato, R.; Scharf, N.; Scherini, V.; Schieler, H.; Schiffer, P.; Schmidt, A.; Schmidt, F.; Schmidt, T.; Scholten, O.; Schoorlemmer, H.; Schovancova, J.; Schovánek, P.; Schroeder, F.; Schulte, S.; Schuster, D.; Sciutto, S. J.; Scuderi, M.; Segreto, A.; Semikoz, D.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sidelnik, I.; Sigl, G.; Śmiałkowski, A.; Šmída, R.; Snow, G. R.; Sommers, P.; Sorokin, J.; Spinka, H.; Squartini, R.; Stapleton, J.; Stasielak, J.; Stephan, M.; Stutz, A.; Suarez, F.; Suomijärvi, T.; Supanitsky, A. D.; Šuša, T.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Szuba, M.; Tamashiro, A.; Tapia, A.; Taşcău, O.; Tcaciuc, R.; Tegolo, D.; Thao, N. T.; Thomas, D.; Tiffenberg, J.; Timmermans, C.; Tiwari, D. K.; Tkaczyk, W.; Todero Peixoto, C. J.; Tomé, B.; Tonachini, A.; Travnicek, P.; Tridapalli, D. B.; Tristram, G.; Trovato, E.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van den Berg, A. M.; Vargas Cárdenas, B.; Vázquez, J. R.; Vázquez, R. A.; Veberič, D.; Verzi, V.; Videla, M.; Villaseñor, L.; Wahlberg, H.; Wahrlich, P.; Wainberg, O.; Warner, D.; Watson, A. A.; Weber, M.; Weidenhaupt, K.; Weindl, A.; Westerhoff, S.; Whelan, B. J.; Wieczorek, G.; Wiencke, L.; Wilczyńska, B.; Wilczyński, H.; Will, M.; Williams, C.; Winchen, T.; Winders, L.; Winnick, M. G.; Wommer, M.; Wundheiler, B.; Yamamoto, T.; Younk, P.; Yuan, G.; Zamorano, B.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zaw, I.; Zepeda, A.; Ziolkowski, M.

    2011-04-01

    The advent of the Auger Engineering Radio Array (AERA) necessitates the development of a powerful framework for the analysis of radio measurements of cosmic ray air showers. As AERA performs “radio-hybrid” measurements of air shower radio emission in coincidence with the surface particle detectors and fluorescence telescopes of the Pierre Auger Observatory, the radio analysis functionality had to be incorporated in the existing hybrid analysis solutions for fluorescence and surface detector data. This goal has been achieved in a natural way by extending the existing Auger Offline software framework with radio functionality. In this article, we lay out the design, highlights and features of the radio extension implemented in the Auger Offline framework. Its functionality has achieved a high degree of sophistication and offers advanced features such as vectorial reconstruction of the electric field, advanced signal processing algorithms, a transparent and efficient handling of FFTs, a very detailed simulation of detector effects, and the read-in of multiple data formats including data from various radio simulation codes. The source code of this radio functionality can be made available to interested parties on request.

  12. Muons in air showers at the Pierre Auger Observatory: Mean number in highly inclined events

    DOE PAGES

    Aab, Alexander

    2015-03-09

    We present the first hybrid measurement of the average muon number in air showers at ultra-high energies, initiated by cosmic rays with zenith angles between 62° and 80° . Our measurement is based on 174 hybrid events recorded simultaneously with the Surface Detector array and the Fluorescence Detector of the Pierre Auger Observatory. The muon number for each shower is derived by scaling a simulated reference profile of the lateral muon density distribution at the ground until it fits the data. A 1019 eV shower with a zenith angle of 67°, which arrives at the Surface Detector array at anmore » altitude of 1450 m above sea level, contains on average (2.68 ± 0.04 ± 0.48 (sys.)) × 107 muons with energies larger than 0.3 GeV. Finally, the logarithmic gain d ln Nµ/d ln E of muons with increasing energy between 4 × 1018 eV and 5 × 1019 eV is measured to be (1.029 ± 0.024 ± 0.030 (sys.)).« less

  13. Muons in air showers at the Pierre Auger Observatory: Mean number in highly inclined events

    SciTech Connect

    Aab, Alexander

    2015-03-09

    We present the first hybrid measurement of the average muon number in air showers at ultra-high energies, initiated by cosmic rays with zenith angles between 62° and 80° . Our measurement is based on 174 hybrid events recorded simultaneously with the Surface Detector array and the Fluorescence Detector of the Pierre Auger Observatory. The muon number for each shower is derived by scaling a simulated reference profile of the lateral muon density distribution at the ground until it fits the data. A 1019 eV shower with a zenith angle of 67°, which arrives at the Surface Detector array at an altitude of 1450 m above sea level, contains on average (2.68 ± 0.04 ± 0.48 (sys.)) × 107 muons with energies larger than 0.3 GeV. Finally, the logarithmic gain d ln Nµ/d ln E of muons with increasing energy between 4 × 1018 eV and 5 × 1019 eV is measured to be (1.029 ± 0.024 ± 0.030 (sys.)).

  14. Advanced functionality for radio analysis in the Offline software framework of the Pierre Auger Observatory

    SciTech Connect

    Abreu, P.; Aglietta, M.; Ahn, E.J.; Albuquerque, I.F.M.; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Alvarez Castillo, J.; Alvarez-Muniz, J.; Ambrosio, M.; /INFN, Naples /Copenhagen Astron. Observ. /Nijmegen U., IMAPP

    2011-01-01

    The advent of the Auger Engineering Radio Array (AERA) necessitates the development of a powerful framework for the analysis of radio measurements of cosmic ray air showers. As AERA performs 'radio-hybrid' measurements of air shower radio emission in coincidence with the surface particle detectors and fluorescence telescopes of the Pierre Auger Observatory, the radio analysis functionality had to be incorporated in the existing hybrid analysis solutions for fluorescence and surface detector data. This goal has been achieved in a natural way by extending the existing Auger Offline software framework with radio functionality. In this article, we lay out the design, highlights and features of the radio extension implemented in the Auger Offline framework. Its functionality has achieved a high degree of sophistication and offers advanced features such as vectorial reconstruction of the electric field, advanced signal processing algorithms, a transparent and efficient handling of FFTs, a very detailed simulation of detector effects, and the read-in of multiple data formats including data from various radio simulation codes. The source code of this radio functionality can be made available to interested parties on request.

  15. Neutron detector

    DOEpatents

    Stephan, Andrew C.; Jardret; Vincent D.

    2011-04-05

    A neutron detector has a volume of neutron moderating material and a plurality of individual neutron sensing elements dispersed at selected locations throughout the moderator, and particularly arranged so that some of the detecting elements are closer to the surface of the moderator assembly and others are more deeply embedded. The arrangement captures some thermalized neutrons that might otherwise be scattered away from a single, centrally located detector element. Different geometrical arrangements may be used while preserving its fundamental characteristics. Different types of neutron sensing elements may be used, which may operate on any of a number of physical principles to perform the function of sensing a neutron, either by a capture or a scattering reaction, and converting that reaction to a detectable signal. High detection efficiency, an ability to acquire spectral information, and directional sensitivity may be obtained.

  16. Neutron detector

    SciTech Connect

    Stephan, Andrew C; Jardret, Vincent D

    2009-04-07

    A neutron detector has a volume of neutron moderating material and a plurality of individual neutron sensing elements dispersed at selected locations throughout the moderator, and particularly arranged so that some of the detecting elements are closer to the surface of the moderator assembly and others are more deeply embedded. The arrangement captures some thermalized neutrons that might otherwise be scattered away from a single, centrally located detector element. Different geometrical arrangements may be used while preserving its fundamental characteristics. Different types of neutron sensing elements may be used, which may operate on any of a number of physical principles to perform the function of sensing a neutron, either by a capture or a scattering reaction, and converting that reaction to a detectable signal. High detection efficiency, an ability to acquire spectral information, and directional sensitivity may be obtained.

  17. Proceedings of the Second Infrared Detector Technology Workshop

    NASA Technical Reports Server (NTRS)

    Mccreight, C. R. (Compiler)

    1986-01-01

    The workshop focused on infrared detector, detector array, and cryogenic electronic technologies relevant to low-background space astronomy. Papers are organized into the following categories: discrete infrared detectors and readout electronics; advanced bolometers; intrinsic integrated infrared arrays; and extrinsic integrated infrared arrays. Status reports on the Space Infrared Telescope Facility (SIRTF) and Infrared Space Observatory (ISO) programs are also included.

  18. GPM Core Observatory Launch Animation

    NASA Video Gallery

    This animation depicts the launch of the Global Precipitation Measurement (GPM) Core Observatory satellite from Tanegashima Space Center, Japan. The launch is currently scheduled for Feb. 27, 2014....

  19. Assembled Chandra X-Ray Observatory

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This photograph shows TRW technicians preparing the assembled Chandra X-Ray Observatory (CXO) for an official unveiling at TRW Space and Electronics Group of Redondo Beach, California. The CXO is formerly known as the Advanced X-Ray Astrophysics Facility (AXAF), which was renamed in honor of the late Indian-American Astronomer, Subrahmanyan Chandrasekhar in 1999. The CXO will help astronomers world-wide better understand the structure and evolution of the universe by studying powerful sources of x-rays such as exploding stars, matter falling into black holes, and other exotic celestial objects. X-ray astronomy can only be done from space because Earth's atmosphere blocks x-rays from reaching the surface. The Observatory provides images that are 50 times more detailed than previous x-ray missions. At more than 45 feet in length and weighing more than 5 tons, it will be one of the largest objects ever placed in Earth orbit by the Space Shuttle. TRW, Inc. was the prime contractor and assembled and tested the observatory for NASA. The CXO program is managed by the Marshall Space Flight Center. The Observatory was launched on July 22, 1999 aboard the Space Shuttle Columbia, STS-93 mission. (Image courtesy of TRW)

  20. Assembled Chandra X-Ray Observatory

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This photograph shows a TRW technician inspecting the completely assembled Chandra X-ray Observatory (CXO) in the Thermal Vacuum Chamber at TRW Space and Electronics Group of Redondo Beach, California. The CXO is formerly known as the Advanced X-Ray Astrophysics Facility (AXAF), which was renamed in honor of the late Indian-American Astronomer, Subrahmanyan Chandrasekhar in 1999. The CXO will help astronomers worldwide better understand the structure and evolution of the universe by studying powerful sources of x-rays such as exploding stars, matter falling into black holes and other exotic celestial objects. X-ray astronomy can only be done from space because Earth's atmosphere blocks x-rays from reaching the surface. The Observatory provides images that are 50 times more detailed than previous x-ray missions. At more than 45 feet in length and weighing more than 5 tons, it will be one of the largest objects ever placed in Earth orbit by the Space Shuttle. TRW, Inc. was the prime contractor and assembled and tested the observatory for NASA. The CXO program is managed by the Marshall Space Flight Center. The Observatory was launched on July 22, 1999 aboard the Space Shuttle Columbia, STS-93 mission. (Image courtesy of TRW)

  1. INO prototype detector and data acquisition system

    NASA Astrophysics Data System (ADS)

    Behere, Anita; Bhatia, M. S.; Chandratre, V. B.; Datar, V. M.; Mukhopadhyay, P. K.; Jena, Satyajit; Viyogi, Y. P.; Bhattacharya, Sudeb; Saha, Satyajit; Bhide, Sarika; Kalmani, S. D.; Mondal, N. K.; Nagaraj, P.; Nagesh, B. K.; Rao, Shobha K.; Reddy, L. V.; Saraf, M.; Satyanarayana, B.; Shinde, R. R.; Upadhya, S. S.; Verma, P.; Biswas, Saikat; Chattopadhyay, Subhasish; Sarma, P. R.

    2009-05-01

    India-based Neutrino Observatory (INO) collaboration is proposing to build a 50 kton magnetised iron calorimetric (ICAL) detector in an underground laboratory to be located in South India. Glass resistive plate chambers (RPCs) of about 2 m×2 m in size will be used as active elements for the ICAL detector. As a first step towards building the ICAL detector, a 35 ton prototype of the same is being set up over ground to track cosmic muons. Design and construction details of the prototype detector and its data acquisition system will be discussed. Some of the preliminary results from the detector stack will also be highlighted.

  2. High-energy detector

    DOEpatents

    Bolotnikov, Aleksey E.; Camarda, Giuseppe; Cui, Yonggang; James, Ralph B.

    2011-11-22

    The preferred embodiments are directed to a high-energy detector that is electrically shielded using an anode, a cathode, and a conducting shield to substantially reduce or eliminate electrically unshielded area. The anode and the cathode are disposed at opposite ends of the detector and the conducting shield substantially surrounds at least a portion of the longitudinal surface of the detector. The conducting shield extends longitudinally to the anode end of the detector and substantially surrounds at least a portion of the detector. Signals read from one or more of the anode, cathode, and conducting shield can be used to determine the number of electrons that are liberated as a result of high-energy particles impinge on the detector. A correction technique can be implemented to correct for liberated electron that become trapped to improve the energy resolution of the high-energy detectors disclosed herein.

  3. The Sudbury Neutrino Observatory

    NASA Astrophysics Data System (ADS)

    Bellerive, A.; Klein, J. R.; McDonald, A. B.; Noble, A. J.; Poon, A. W. P.

    2016-07-01

    This review paper provides a summary of the published results of the Sudbury Neutrino Observatory (SNO) experiment that was carried out by an international scientific collaboration with data collected during the period from 1999 to 2006. By using heavy water as a detection medium, the SNO experiment demonstrated clearly that solar electron neutrinos from 8B decay in the solar core change into other active neutrino flavors in transit to Earth. The reaction on deuterium that has equal sensitivity to all active neutrino flavors also provides a very accurate measure of the initial solar flux for comparison with solar models. This review summarizes the results from three phases of solar neutrino detection as well as other physics results obtained from analyses of the SNO data.

  4. LCOGT network observatory operations

    NASA Astrophysics Data System (ADS)

    Pickles, Andrew; Hjelstrom, Annie; Boroson, Todd; Burleson, Ben; Conway, Patrick; De Vera, Jon; Elphick, Mark; Haworth, Brian; Rosing, Wayne; Saunders, Eric; Thomas, Doug; White, Gary; Willis, Mark; Walker, Zach

    2014-08-01

    We describe the operational capabilities of the Las Cumbres Observatory Global Telescope Network. We summarize our hardware and software for maintaining and monitoring network health. We focus on methodologies to utilize the automated system to monitor availability of sites, instruments and telescopes, to monitor performance, permit automatic recovery, and provide automatic error reporting. The same jTCS control system is used on telescopes of apertures 0.4m, 0.8m, 1m and 2m, and for multiple instruments on each. We describe our network operational model, including workloads, and illustrate our current tools, and operational performance indicators, including telemetry and metrics reporting from on-site reductions. The system was conceived and designed to establish effective, reliable autonomous operations, with automatic monitoring and recovery - minimizing human intervention while maintaining quality. We illustrate how far we have been able to achieve that.

  5. The virtual observatory registry

    NASA Astrophysics Data System (ADS)

    Demleitner, M.; Greene, G.; Le Sidaner, P.; Plante, R. L.

    2014-11-01

    In the Virtual Observatory (VO), the Registry provides the mechanism with which users and applications discover and select resources-typically, data and services-that are relevant for a particular scientific problem. Even though the VO adopted technologies in particular from the bibliographic community where available, building the Registry system involved a major standardisation effort, involving about a dozen interdependent standard texts. This paper discusses the server-side aspects of the standards and their application, as regards the functional components (registries), the resource records in both format and content, the exchange of resource records between registries (harvesting), as well as the creation and management of the identifiers used in the system based on the notion of authorities. Registry record authors, registry operators or even advanced users thus receive a big picture serving as a guideline through the body of relevant standard texts. To complete this picture, we also mention common usage patterns and open issues as appropriate.

  6. Orbiting Carbon Observatory

    NASA Technical Reports Server (NTRS)

    Miller, Charles E.

    2005-01-01

    Human impact on the environment has produced measurable changes in the geological record since the late 1700s. Anthropogenic emissions of CO2 today may cause the global climate to depart for its natural behavior for many millenia. CO2 is the primary anthropogenic driver of climate change. The Orbiting Carbon Observatory goals are to help collect measurements of atmospheric CO2, answering questions such as why the atmospheric CO2 buildup varies annually, the roles of the oceans and land ecosystems in absorbing CO2, the roles of North American and Eurasian sinks and how these carbon sinks respond to climate change. The present carbon cycle, CO2 variability, and climate uncertainties due atmospheric CO2 uncertainties are highlighted in this presentation.

  7. Development of Blocked-Impurity-Band-Type Ge Detectors Fabricated with the Surface-Activated Wafer Bonding Method for Far-Infrared Astronomy

    NASA Astrophysics Data System (ADS)

    Hanaoka, M.; Kaneda, H.; Oyabu, S.; Yamagishi, M.; Hattori, Y.; Ukai, S.; Shichi, K.; Wada, T.; Suzuki, T.; Watanabe, K.; Nagase, K.; Baba, S.; Kochi, C.

    2016-07-01

    We report the current status of the development of our new detectors for far-infrared (FIR) astronomy. We develop Blocked-Impurity-Band (BIB)-type Ge detectors to realize large-format compact arrays covering a wide FIR wavelength range up to 200 \\upmu m. We fabricated Ge junction devices of different physical parameters with a BIB-type structure, using the room temperature, surface-activated wafer bonding (SAB) method. We measured the absolute responsivity and the spectral response curve of each device at low temperatures, using an internal blackbody source in a cryostat and a Fourier transform spectrometer, respectively. The results show that the SAB Ge junction devices have significantly higher absolute responsivities and longer cut-off wavelengths of the spectral response than the conventional bulk Ge:Ga device. Based upon the results, we discuss the optimum parameters of SAB Ge junction devices for FIR detectors. We conclude that SAB Ge junction devices possess a promising applicability to next-generation FIR detectors covering wavelengths up to ˜ 200 \\upmu m with high responsivity. As a next step, we plan to fabricate a BIB-type Ge array device in combination with a low-power cryogenic readout integrated circuit.

  8. Global geodetic observatories

    NASA Astrophysics Data System (ADS)

    Boucher, Claude; Pearlman, Mike; Sarti, Pierguido

    2015-01-01

    Global geodetic observatories (GGO) play an increasingly important role both for scientific and societal applications, in particular for the maintenance and evolution of the reference frame and those applications that rely on the reference frame for their viability. The International Association of Geodesy (IAG), through the Global Geodetic Observing System (GGOS), is fully involved in coordinating the development of these systems and ensuring their quality, perenniality and accessibility. This paper reviews the current role, basic concepts, and some of the critical issues associated with the GGOs, and advocates for their expansion to enhance co-location with other observing techniques (gravity, meteorology, etc). The historical perspective starts with the MERIT campaign, followed by the creation of international services (IERS, IGS, ILRS, IVS, IDS, etc). It provides a basic definition of observing systems and observatories and the build up of the international networks and the role of co-locations in geodesy and geosciences and multi-technique processing and data products. This paper gives special attention to the critical topic of local surveys and tie vectors among co-located systems in sites; the agreement of space geodetic solutions and the tie vectors now place one of the most significant limitations on the quality of integrated data products, most notably the ITRF. This topic focuses on survey techniques, extrapolation to instrument reference points, computation techniques, systematic biases, and alignment of the individual technique reference frames into ITRF. The paper also discusses the design, layout and implementation of network infrastructure, including the role of GGOS and the benefit that would be achieved with better standardization and international governance.

  9. Rolloff Roof Observatory Construction (Abstract)

    NASA Astrophysics Data System (ADS)

    Ulowetz, J. H.

    2015-12-01

    (Abstract only) Lessons learned about building an observatory by someone with limited construction experience, and the advantages of having one for imaging and variable star studies. Sample results shown of composite light curves for cataclysmic variables UX UMa and V1101 Aql with data from my observatory combined with data from others around the world.

  10. Searching for slow-developing cosmic-ray showers: Looking for evidence of exotic primaries at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Mayotte, Eric William

    The central purpose of this research was to add the event propagation velocity to the list of shower parameters that the Florescence Detector of Pierre Auger Observatory is capable of measuring. This capability was then leveraged to differentiate exotic slow moving events from the rest of the cosmic ray flux. Clearly, by relativistic necessity, all known cosmic ray primaries can only cause a measurable extensive air shower at velocities indistinguishably close to the speed of light. Therefore any accurate observation of an event propagating slower than the speed of light would provide an unmistakable indicator of new physics. A particle must possess very specific characteristics in order to be capable of producing a slow shower. High mass Strangelets, macroscopic dark matter, and super-symmetric Q-Balls were identified as strong candidates. Theory supporting high mass Strangelets and macroscopic dark matter appeared too late for full inclusion in this work, however super-symmetric Q-Balls were thoroughly examined. CORSIKA simulations were used to show that the fluorescence detector of the Pierre Auger Observatory has sensitivity to Q-Balls with a mass MQ > 3.25 x 1027 GeV c--2 while the surface detector is sensitive at a mass MQ > 1.15 x 10 27GeV c--2. The Pierre Auger Observatory was shown to be capable of accurately measuring a wide range of velocities with two independent methods. These methods were applied to 7 years of data and one candidate slow event was identified. This candidate measurement proved to be due to a rare and interesting, but ultimately, non-exotic effect, which when accounted for resulted in the event being measured normally. As a result of this, no exotic candidate events were found in the search. Recommendations are made for improving the result and promising alternative search methods are presented.

  11. Multiscale soil moisture measurement for mapping surface runoff generation on torrential headwater catchments (Draix-Bléone field observatory, South Alps, France)

    NASA Astrophysics Data System (ADS)

    Florian, Mallet; Vincent, Marc; Johnny, Douvinet; Philippe, Rossello; Bouteiller Caroline, Le; Jean-Philippe, Malet; Julien, Gance

    2015-04-01

    soilwater flow of from the surface to - 30 cm. Another distributed approach will be carried out from a measurement of cosmic neutrons mitigation (Cosmic ray sensor) to estimate a soil moisture averaged value over 40 ha (Zreda et al., 2012). Finally, the smallest scale (slope and catchment) will be approached using remote sensing with a drone and/or satellite imagery (IR, passive and active microwave). This concatenation of scales with different combinations of time steps should enable us to better understand the hydrological dynamics in torrential environments. It aims at mapping the stormflow generation on a catchment at the flood scale and defining the main determinants of surface runoff. These results may contribute to the improvement of runoff simulation and flood prediction. References : Uhlenbrook S., J.J. McDonnell and C. Leibundgut, 2003. Preface: Runoff generation implications for river basin modelling. Hydrological Processes, Special Issue, 17: 197-198. Andrew W. Western, Sen-Lin Zhou, Rodger B. Grayson, Thomas A. MacMahon, Günter Blöshl, David J. Wilson, 2004. Spatial correlation of soil moisture in small catchments and its relationship to dominant spatial hydrological processes. Journal of Hydrology 286. Zreda, M., Shuttleworth WJ., Zeng X., Zweck C., Desilets D., Franz TE. et al., 2012. COSMOS: the COsmic-ray Soil Moisture Observing System. Hydrology and Earth System Sciences, 16(11): 4079-4099.

  12. Ion detector

    DOEpatents

    Tullis, Andrew M.

    1987-01-01

    An improved ion detector device of the ionization detection device chamber ype comprises an ionization chamber having a central electrode therein surrounded by a cylindrical electrode member within the chamber with a collar frictionally fitted around at least one of the electrodes. The collar has electrical contact means carried in an annular groove in an inner bore of the collar to contact the outer surface of the electrode to provide electrical contact between an external terminal and the electrode without the need to solder leads to the electrode.

  13. Study of heliospheric effects on galactic cosmic ray fluxes near Earth using low energy modes of the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Saleh, Ahmed; Pierre Auger Collaboration

    2016-04-01

    Surface detector array (SD) of the Pierre Auger Observatory has the capability to observe variations in the flux of low energy secondary cosmic ray particles. Flux rates of low energy particles can be obtained either from particle count rates (scaler mode) or from charge distribution of the pulses (histogram mode), detected by individual water Cherenkov detectors (WCD). In scaler mode, SD is sensitive to particles that deposit energy between ~15 MeV and ~100 MeV in a WCD, while in histogram mode the deposited energy range can be extended up to ~1 GeV. These two low energy detection modes are excellent tools for monitoring modulations of the galactic cosmic ray flux, related to solar activity, such as Forbush decreases (with typical duration of several hours to weeks) and Solar cycle (with a duration of several years), as they provide fluxes of cosmic rays with different energies at the same detector. In this contribution we present an analysis of the effects of space weather and space climate on low energy mode data collected by the Pierre Auger Observatory in the period between 2006 and 2013. In particular, we focus on the long term trend of the cosmic ray flux. In addition to the standard corrections for atmospheric effects such as pressure, the analysis takes into account also the corrections for the long term evolution of the response of the surface detectors. Results show good correlation of the corrected low energy mode Auger data with neutron flux measurements by the global neutron monitoring network (NMDB).

  14. The Lateral Trigger Probability function for the Ultra-High Energy Cosmic Ray showers detected by the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Pierre Auger Collaboration; Abreu, P.; Aglietta, M.; Ahn, E. J.; Albuquerque, I. F. M.; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Antičić, T.; Anzalone, A.; Aramo, C.; Arganda, E.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Bäcker, T.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Bäuml, J.; Beatty, J. J.; Becker, B. R.; Becker, K. H.; Bellétoile, A.; Bellido, J. A.; Benzvi, S.; Berat, C.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Blümer, H.; Boháčová, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brogueira, P.; Brown, W. C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Burton, R. E.; Caballero-Mora, K. S.; Caramete, L.; Caruso, R.; Castellina, A.; Catalano, O.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Cheng, S. H.; Chiavassa, A.; Chinellato, J. A.; Chou, A.; Chudoba, J.; Clay, R. W.; Coluccia, M. R.; Conceição, R.; Contreras, F.; Cook, H.; Cooper, M. J.; Coppens, J.; Cordier, A.; Cotti, U.; Coutu, S.; Covault, C. E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; de Domenico, M.; de Donato, C.; de Jong, S. J.; de La Vega, G.; de Mello Junior, W. J. M.; de Mello Neto, J. R. T.; de Mitri, I.; de Souza, V.; de Vries, K. D.; Decerprit, G.; Del Peral, L.; Deligny, O.; Dembinski, H.; Dhital, N.; di Giulio, C.; Diaz, J. C.; Díaz Castro, M. L.; Diep, P. N.; Dobrigkeit, C.; Docters, W.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; Dos Anjos, J. C.; Dova, M. T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C. O.; Etchegoyen, A.; Facal San Luis, P.; Fajardo Tapia, I.; Falcke, H.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Ferrero, A.; Fick, B.; Filevich, A.; Filipčič, A.; Fliescher, S.; Fracchiolla, C. E.; Fraenkel, E. D.; Fröhlich, U.; Fuchs, B.; Gaior, R.; Gamarra, R. F.; Gambetta, S.; García, B.; García Gámez, D.; Garcia-Pinto, D.; Gascon, A.; Gemmeke, H.; Gesterling, K.; Ghia, P. L.; Giaccari, U.; Giller, M.; Glass, H.; Gold, M. S.; Golup, G.; Gomez Albarracin, F.; Gómez Berisso, M.; Gonçalves, P.; Gonzalez, D.; Gonzalez, J. G.; Gookin, B.; Góra, D.; Gorgi, A.; Gouffon, P.; Gozzini, S. R.; Grashorn, E.; Grebe, S.; Griffith, N.; Grigat, M.; Grillo, A. F.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Guzman, A.; Hague, J. D.; Hansen, P.; Harari, D.; Harmsma, S.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A. E.; Hojvat, C.; Hollon, N.; Holmes, V. C.; Homola, P.; Hörandel, J. R.; Horneffer, A.; Hrabovský, M.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jarne, C.; Jiraskova, S.; Kadija, K.; Kampert, K. H.; Karhan, P.; Kasper, P.; Kégl, B.; Keilhauer, B.; Keivani, A.; Kelley, J. L.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D.-H.; Kotera, K.; Krohm, N.; Krömer, O.; Kruppke-Hansen, D.; Kuehn, F.; Kuempel, D.; Kulbartz, J. K.; Kunka, N.; La Rosa, G.; Lachaud, C.; Lautridou, P.; Leão, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Lemiere, A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; López, R.; Lopez Agüera, A.; Louedec, K.; Lozano Bahilo, J.; Lucero, A.; Ludwig, M.; Lyberis, H.; Maccarone, M. C.; Macolino, C.; Maldera, S.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, J.; Marin, V.; Maris, I. C.; Marquez Falcon, H. R.; Marsella, G.; Martello, D.; Martin, L.; Martinez, H.; Martínez Bravo, O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mazur, P. O.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Mertsch, P.; Meurer, C.; Mićanović, S.; Micheletti, M. I.; Miller, W.; Miramonti, L.; Mollerach, S.; Monasor, M.; Monnier Ragaigne, D.; Montanet, F.; Morales, B.; Morello, C.; Moreno, E.; Moreno, J. C.; Morris, C.; Mostafá, M.; Moura, C. A.; Mueller, S.; Muller, M. A.; Müller, G.; Münchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J. L.; Navas, S.; Necesal, P.; Nellen, L.; Nelles, A.; Nhung, P. T.; Niemietz, L.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nožka, L.; Nyklicek, M.; Oehlschläger, J.; Olinto, A.; Oliva, P.; Olmos-Gilbaja, V. M.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Parsons, R. D.; Pastor, S.; Paul, T.; Pech, M.; Pȩkala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrinca, P.; Petrolini, A.; Petrov, Y.; Petrovic, J.; Pfendner, C.; Phan, N.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.; Platino, M.; Ponce, V. H.; Pontz, M.; Privitera, P.; Prouza, M.; Quel, E. J.; Querchfeld, S.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Revenu, B.; Ridky, J.; Riggi, S.; Risse, M.; Ristori, P.; Rivera, H.; Rizi, V.; Roberts, J.; Robledo, C.; Rodrigues de Carvalho, W.; Rodriguez, G.; Rodriguez Martino, J.; Rodriguez Rojo, J.; Rodriguez-Cabo, I.; Rodríguez-Frías, M. D.; Ros, G.; Rosado, J.; Rossler, T.; Roth, M.; Rouillé-D'Orfeuil, B.; Roulet, E.; Rovero, A. C.; Rühle, C.; Salamida, F.; Salazar, H.; Salina, G.; Sánchez, F.; Santander, M.; Santo, C. E.; Santos, E.; Santos, E. M.; Sarazin, F.; Sarkar, B.; Sarkar, S.; Sato, R.; Scharf, N.; Scherini, V.; Schieler, H.; Schiffer, P.; Schmidt, A.; Schmidt, F.; Schmidt, T.; Scholten, O.; Schoorlemmer, H.; Schovancova, J.; Schovánek, P.; Schröder, F.; Schulte, S.; Schuster, D.; Sciutto, S. J.; Scuderi, M.; Segreto, A.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sidelnik, I.; Sigl, G.; Silva Lopez, H. H.; Śmiałkowski, A.; Šmída, R.; Snow, G. R.; Sommers, P.; Sorokin, J.; Spinka, H.; Squartini, R.; Stapleton, J.; Stasielak, J.; Stephan, M.; Strazzeri, E.; Stutz, A.; Suarez, F.; Suomijärvi, T.; Supanitsky, A. D.; Šuša, T.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Szuba, M.; Tamashiro, A.; Tapia, A.; Tartare, M.; Taşcău, O.; Tavera Ruiz, C. G.; Tcaciuc, R.; Tegolo, D.; Thao, N. T.; Thomas, D.; Tiffenberg, J.; Timmermans, C.; Tiwari, D. K.; Tkaczyk, W.; Todero Peixoto, C. J.; Tomé, B.; Tonachini, A.; Travnicek, P.; Tridapalli, D. B.; Tristram, G.; Trovato, E.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van den Berg, A. M.; Varela, E.; Vargas Cárdenas, B.; Vázquez, J. R.; Vázquez, R. A.; Veberič, D.; Verzi, V.; Vicha, J.; Videla, M.; Villaseñor, L.; Wahlberg, H.; Wahrlich, P.; Wainberg, O.; Warner, D.; Watson, A. A.; Weber, M.; Weidenhaupt, K.; Weindl, A.; Westerhoff, S.; Whelan, B. J.; Wieczorek, G.; Wiencke, L.; Wilczyńska, B.; Wilczyński, H.; Will, M.; Williams, C.; Winchen, T.; Winders, L.; Winnick, M. G.; Wommer, M.; Wundheiler, B.; Yamamoto, T.; Yapici, T.; Younk, P.; Yuan, G.; Yushkov, A.; Zamorano, B.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zaw, I.; Zepeda, A.; Ziolkowski, M.

    2011-12-01

    In this paper we introduce the concept of Lateral Trigger Probability (LTP) function, i.e., the probability for an Extensive Air Shower (EAS) to trigger an individual detector of a ground based array as a function of distance to the shower axis, taking into account energy, mass and direction of the primary cosmic ray. We apply this concept to the surface array of the Pierre Auger Observatory consisting of a 1.5 km spaced grid of about 1600 water Cherenkov stations. Using Monte Carlo simulations of ultra-high energy showers the LTP functions are derived for energies in the range between 1017 and 1019 eV and zenith angles up to 65°. A parametrization combining a step function with an exponential is found to reproduce them very well in the considered range of energies and zenith angles. The LTP functions can also be obtained from data using events simultaneously observed by the fluorescence and the surface detector of the Pierre Auger Observatory (hybrid events). We validate the Monte Carlo results showing how LTP functions from data are in good agreement with simulations.

  15. Ancient "Observatories" - A Relevant Concept?

    NASA Astrophysics Data System (ADS)

    Belmonte, Juan Antonio

    It is quite common, when reading popular books on astronomy, to see a place referred to as "the oldest observatory in the world". In addition, numerous books on archaeoastronomy, of various levels of quality, frequently refer to the existence of "prehistoric" or "ancient" observatories when describing or citing monuments that were certainly not built with the primary purpose of observing the skies. Internet sources are also guilty of this practice. In this chapter, the different meanings of the word observatory will be analyzed, looking at how their significances can be easily confused or even interchanged. The proclaimed "ancient observatories" are a typical result of this situation. Finally, the relevance of the concept of the ancient observatory will be evaluated.

  16. The High Altitude Water Cherenkov (HAWC) Observatory

    NASA Astrophysics Data System (ADS)

    Springer, Wayne

    2014-06-01

    The High Altitude Water Cherenkov (HAWC) observatory is a continuously operated, wide field of view detector based upon a water Cherenkov technology developed by the Milagro experiment. HAWC observes, at an elevation of 4100 m on Sierra Negra Mountain in Mexico, extensive air showers initiated by gamma and cosmic rays. The completed detector will consist of 300 closely spaced water tanks each instrumented with four photomultiplier tubes that provide timing and charge information used to reconstruct energy and arrival direction. HAWC has been optimized to observe transient and steady emission from point as well as diffuse sources of gamma rays in the energy range from several hundred GeV to several hundred TeV. Studies in solar physics as well as the properties of cosmic rays will also be performed. HAWC has been making observations at various stages of deployment since completion of 10% of the array in summer 2012. A discussion of the detector design, science capabilities, current construction/commissioning status, and first results will be presented...

  17. Design support of the Burst and Transient Source Experiment (BATSE) of the Gamma Ray Observatory (GRO) mission

    NASA Technical Reports Server (NTRS)

    Stephan, E. A., Jr.

    1986-01-01

    Engineering design specifications and development of the large area detector and photomultiplier tube assemblies for the Burst and Transient Source Experiment (BATSE) of the Gamma Ray Observatory (GRO) mission are examined.

  18. Astrophysics Motivation behind the Pierre Auger Southern Observatory Enhancements

    SciTech Connect

    Medina-Tanco, Gustavo; Collaboration, for the Pierre Auger

    2007-09-01

    The Pierre Auger Collaboration intends to extend the energy range of its southern observatory in Argentina for high quality data from 0.1 to 3 EeV. The extensions, described in accompanying papers, include three additional fluorescence telescopes with a more elevated field of view (HEAT) and a nested surface array with 750 and 433 m spacing respectively and additional muon detection capabilities (AMIGA). The enhancement of the detector will allow measurement of cosmic rays, using the same techniques, from below the second knee up to the highest energies observed. The evolution of the spectrum through the second knee and ankle, and corresponding predicted changes in composition, are crucial to the understanding of the end of Galactic confinement and the effects of propagation on the lower energy portion of the extragalactic flux. The latter is strongly related to the cosmological distribution of sources and to the composition of the injected spectrum. We discuss the science motivation behind these enhancements as well as the impact of combined HEAT and AMIGA information on the assessment of shower simulations and reconstruction techniques.

  19. Particle impact location detector

    NASA Technical Reports Server (NTRS)

    Auer, S. O.

    1974-01-01

    Detector includes delay lines connected to each detector surface strip. When several particles strike different strips simultaneously, pulses generated by each strip are time delayed by certain intervals. Delay time for each strip is known. By observing time delay in pulse, it is possible to locate strip that is struck by particle.

  20. Technology development for a neutrino astrophysical observatory. Letter of intent

    SciTech Connect

    Chaloupka, V.; Cole, T.; Crawford, H.J.

    1996-02-01

    The authors propose a set of technology developments relevant to the design of an optimized Cerenkov detector for the study of neutrino interactions of astrophysical interest. Emphasis is placed on signal processing innovations that enhance significantly the quality of primary data. These technical advances, combined with field experience from a follow-on test deployment, are intended to provide a basis for the engineering design for a kilometer-scale Neutrino Astrophysical Observatory.

  1. Technology Development for a Neutrino AstrophysicalObservatory

    SciTech Connect

    Chaloupka, V.; Cole, T.; Crawford, H.J.; He, Y.D.; Jackson, S.; Kleinfelder, S.; Lai, K.W.; Learned, J.; Ling, J.; Liu, D.; Lowder, D.; Moorhead, M.; Morookian, J.M.; Nygren, D.R.; Price, P.B.; Richards, A.; Shapiro, G.; Shen, B.; Smoot, George F.; Stokstad, R.G.; VanDalen, G.; Wilkes, J.; Wright, F.; Young, K.

    1996-02-01

    We propose a set of technology developments relevant to the design of an optimized Cerenkov detector for the study of neutrino interactions of astrophysical interest. Emphasis is placed on signal processing innovations that enhance significantly the quality of primary data. These technical advances, combined with field experience from a follow-on test deployment, are intended to provide a basis for the engineering design for a kilometer-scale Neutrino Astrophysical Observatory.

  2. Cell surface and cell outline imaging in plant tissues using the backscattered electron detector in a variable pressure scanning electron microscope

    PubMed Central

    2013-01-01

    Background Scanning electron microscopy (SEM) has been used for high-resolution imaging of plant cell surfaces for many decades. Most SEM imaging employs the secondary electron detector under high vacuum to provide pseudo-3D images of plant organs and especially of surface structures such as trichomes and stomatal guard cells; these samples generally have to be metal-coated to avoid charging artefacts. Variable pressure-SEM allows examination of uncoated tissues, and provides a flexible range of options for imaging, either with a secondary electron detector or backscattered electron detector. In one application, we used the backscattered electron detector under low vacuum conditions to collect images of uncoated barley leaf tissue followed by simple quantification of cell areas. Results Here, we outline methods for backscattered electron imaging of a variety of plant tissues with particular focus on collecting images for quantification of cell size and shape. We demonstrate the advantages of this technique over other methods to obtain high contrast cell outlines, and define a set of parameters for imaging Arabidopsis thaliana leaf epidermal cells together with a simple image analysis protocol. We also show how to vary parameters such as accelerating voltage and chamber pressure to optimise imaging in a range of other plant tissues. Conclusions Backscattered electron imaging of uncoated plant tissue allows acquisition of images showing details of plant morphology together with images of high contrast cell outlines suitable for semi-automated image analysis. The method is easily adaptable to many types of tissue and suitable for any laboratory with standard SEM preparation equipment and a variable-pressure-SEM or tabletop SEM. PMID:24135233

  3. Klimovskaya: A new geomagnetic observatory

    NASA Astrophysics Data System (ADS)

    Soloviev, A. A.; Sidorov, R. V.; Krasnoperov, R. I.; Grudnev, A. A.; Khokhlov, A. V.

    2016-05-01

    In 2011 Geophysical Center RAS (GC RAS) began to deploy the Klimovskaya geomagnetic observatory in the south of Arkhangelsk region on the territory of the Institute of Physiology of Natural Adaptations, Ural Branch, Russian Academy of Sciences (IPNA UB RAS). The construction works followed the complex of preparatory measures taken in order to confirm that the observatory can be constructed on this territory and to select the optimal configuration of observatory structures. The observatory equipping stages are described in detail, the technological and design solutions are described, and the first results of the registered data quality control are presented. It has been concluded that Klimovskaya observatory can be included in INTERMAGNET network. The observatory can be used to monitor and estimate geomagnetic activity, because it is located at high latitudes and provides data in a timely manner to the scientific community via the web-site of the Russian-Ukrainian Geomagnetic Data Center. The role of ground observatories such as Klimovskaya remains critical for long-term observations of secular variation and for complex monitoring of the geomagnetic field in combination with low-orbiting satellite data.

  4. The Solar Dynamics Observatory

    NASA Technical Reports Server (NTRS)

    Pesnell, William D.

    2008-01-01

    The Solar Dynamics Observatory (SDO) is the first Space Weather Mission in NASA's Living With a Star Program. SDO's main goal is to understand, driving towards a predictive capability, those solar variations that influence life on Earth and humanity's technological systems. The past decade has seen an increasing emphasis on understanding the entire Sun, from the nuclear reactions at the core to the development and loss of magnetic loops in the corona. SDO's three science investigations (HMI, AIA, and EVE) will determine how the Sun's magnetic field is generated and structured, how this stored magnetic energy is released into the heliosphere and geospace as the solar wind, energetic particles, and variations in the solar irradiance. SDO will return full-disk Dopplergrams, full-disk vector magnetograms, full-disk images at nine EIUV wavelengths, and EUV spectral irradiances, all taken at a rapid cadence. This means you can 'observe the database' to study events, but we can also move forward in producing quantitative models of what the Sun is doing today. SDO is scheduled to launch in 2008 on an Atlas V rocket from the Kennedy Space Center, Cape Canaveral, Florida. The satellite will fly in a 28 degree inclined geosynchronous orbit about the longitude of New Mexico, where a dedicated Ka-band ground station will receive the 150 Mbps data flow. How SDO data will transform the study of the Sun and its affect on Space Weather studies will be discussed.

  5. 10 meter airborne observatory

    NASA Astrophysics Data System (ADS)

    Ditto, Thomas D.; Ritter, Joseph M.

    2008-07-01

    Inside an aircraft fuselage there is little room for the mass of all the instrumentation of a ground-based observatory much less a primary objective aperture at the scale of 10 meters. We have proposed a solution that uses a primary objective grating (POG) which matches the considerable length of the aircraft, approximately 10 meters, and conforms to aircraft aerodynamics. Light collected by the POG is diffracted at an angle of grazing exodus inside the aircraft where it is disambiguated by an optical train that fits within to the interior tunnel. Inside the aircraft, light is focused by a parabolic mirror onto a spectrograph slit. The design has a special benefit in that all objects in the field-of-view of the free spectral range of the POG can have their spectra taken as the aircraft changes orientation. We suggest flight planes that will improve integration times, angular resolution and spectral resolution to acquire targets of high stellar magnitudes or alternatively increase the number of sources acquired per flight at the cost of sensitivity.

  6. Calibration of the Reflected Solar Instrument for the Climate Absolute Radiance and Refractivity Observatory

    NASA Technical Reports Server (NTRS)

    Thome, Kurtis; Barnes, Robert; Baize, Rosemary; O'Connell, Joseph; Hair, Jason

    2010-01-01

    The Climate Absolute Radiance and Refractivity Observatory (CLARREO) plans to observe climate change trends over decadal time scales to determine the accuracy of climate projections. The project relies on spaceborne earth observations of SI-traceable variables sensitive to key decadal change parameters. The mission includes a reflected solar instrument retrieving at-sensor reflectance over the 320 to 2300 nm spectral range with 500-m spatial resolution and 100-km swath. Reflectance is obtained from the ratio of measurements of the earth s surface to those while viewing the sun relying on a calibration approach that retrieves reflectance with uncertainties less than 0.3%. The calibration is predicated on heritage hardware, reduction of sensor complexity, adherence to detector-based calibration standards, and an ability to simulate in the laboratory on-orbit sources in both size and brightness to provide the basis of a transfer to orbit of the laboratory calibration including a link to absolute solar irradiance measurements.

  7. Searches for ultra-high energy neutrinos at the Pierre Auger observatory

    SciTech Connect

    Alvarez-Muñiz, Jaime

    2015-07-15

    Neutrinos in the sub-EeV energy range and above can be detected and identified with the Surface Detector array of the Pierre Auger Observatory. The identification can be efficiently done for neutrinos of all flavours interacting in the atmosphere, typically above 60° (downward-going), as well as for “Earth-skimming” neutrino interactions in the case of tau neutrinos (upward-going). Three sets of identification criteria were designed to search for downward-going neutrinos in the zenith angle bins 60° − 75° and 75° − 90° as well as for upward-going neutrinos. The three searches have been recently combined, providing, in the absence of candidates in data from 1 January 04 until 31 December 12, a stringent limit to the diffuse flux of ultra-high energy neutrinos.

  8. Upper limit on the diffuse flux of ultrahigh energy tau neutrinos from the Pierre Auger Observatory.

    PubMed

    Abraham, J; Abreu, P; Aglietta, M; Aguirre, C; Allard, D; Allekotte, I; Allen, J; Allison, P; Alvarez-Muñiz, J; Ambrosio, M; Anchordoqui, L; Andringa, S; Anzalone, A; Aramo, C; Argirò, S; Arisaka, K; Armengaud, E; Arneodo, F; Arqueros, F; Asch, T; Asorey, H; Assis, P; Atulugama, B S; Aublin, J; Ave, M; Avila, G; Bäcker, T; Badagnani, D; Barbosa, A F; Barnhill, D; Barroso, S L C; Bauleo, P; Beatty, J J; Beau, T; Becker, B R; Becker, K H; Bellido, J A; BenZvi, S; Berat, C; Bergmann, T; Bernardini, P; Bertou, X; Biermann, P L; Billoir, P; Blanch-Bigas, O; Blanco, F; Blasi, P; Bleve, C; Blümer, H; Bohácová, M; Bonifazi, C; Bonino, R; Boratav, M; Brack, J; Brogueira, P; Brown, W C; Buchholz, P; Bueno, A; Burton, R E; Busca, N G; Caballero-Mora, K S; Cai, B; Camin, D V; Caramete, L; Caruso, R; Carvalho, W; Castellina, A; Catalano, O; Cataldi, G; Cazon, L; Cester, R; Chauvin, J; Chiavassa, A; Chinellato, J A; Chou, A; Chye, J; Clark, P D J; Clay, R W; Colombo, E; Conceição, R; Connolly, B; Contreras, F; Coppens, J; Cordier, A; Cotti, U; Coutu, S; Covault, C E; Creusot, A; Criss, A; Cronin, J; Curutiu, A; Dagoret-Campagne, S; Daumiller, K; Dawson, B R; de Almeida, R M; De Donato, C; de Jong, S J; De La Vega, G; de Mello Junior, W J M; de Mello Neto, J R T; DeMitri, I; de Souza, V; del Peral, L; Deligny, O; Della Selva, A; Delle Fratte, C; Dembinski, H; Di Giulio, C; Diaz, J C; Dobrigkeit, C; D'Olivo, J C; Dornic, D; Dorofeev, A; dos Anjos, J C; Dova, M T; D'Urso, D; Dutan, I; DuVernois, M A; Engel, R; Epele, L; Erdmann, M; Escobar, C O; Etchegoyen, A; Facal San Luis, P; Falcke, H; Farrar, G; Fauth, A C; Fazzini, N; Ferrer, F; Ferry, S; Fick, B; Filevich, A; Filipcic, A; Fleck, I; Fonte, R; Fracchiolla, C E; Fulgione, W; García, B; García Gámez, D; Garcia-Pinto, D; Garrido, X; Geenen, H; Gelmini, G; Gemmeke, H; Ghia, P L; Giller, M; Glass, H; Gold, M S; Golup, G; Gomez Albarracin, F; Gómez Berisso, M; Gómez Herrero, R; Gonçalves, P; Gonçalves do Amaral, M; Gonzalez, D; Gonzalez, J G; González, M; Góra, D; Gorgi, A; Gouffon, P; Grassi, V; Grillo, A F; Grunfeld, C; Guardincerri, Y; Guarino, F; Guedes, G P; Gutiérrez, J; Hague, J D; Hamilton, J C; Hansen, P; Harari, D; Harmsma, S; Harton, J L; Haungs, A; Hauschildt, T; Healy, M D; Hebbeker, T; Hebrero, G; Heck, D; Hojvat, C; Holmes, V C; Homola, P; Hörandel, J; Horneffer, A; Horvat, M; Hrabovský, M; Huege, T; Hussain, M; Iarlori, M; Insolia, A; Ionita, F; Italiano, A; Kaducak, M; Kampert, K H; Karova, T; Kégl, B; Keilhauer, B; Kemp, E; Kieckhafer, R M; Klages, H O; Kleifges, M; Kleinfeller, J; Knapik, R; Knapp, J; Koang, D-H; Krieger, A; Krömer, O; Kuempel, D; Kunka, N; Kusenko, A; La Rosa, G; Lachaud, C; Lago, B L; Lebrun, D; Lebrun, P; Lee, J; Leigui de Oliveira, M A; Letessier-Selvon, A; Leuthold, M; Lhenry-Yvon, I; López, R; Lopez Agüera, A; Lozano Bahilo, J; Luna García, R; Maccarone, M C; Macolino, C; Maldera, S; Mancarella, G; Manceñido, M E; Mandat, D; Mantsch, P; Mariazzi, A G; Maris, I C; Marquez Falcon, H R; Martello, D; Martínez, J; Martínez Bravo, O; Mathes, H J; Matthews, J; Matthews, J A J; Matthiae, G; Maurizio, D; Mazur, P O; McCauley, T; McEwen, M; McNeil, R R; Medina, M C; Medina-Tanco, G; Meli, A; Melo, D; Menichetti, E; Menschikov, A; Meurer, Chr; Meyhandan, R; Micheletti, M I; Miele, G; Miller, W; Mollerach, S; Monasor, M; Monnier Ragaigne, D; Montanet, F; Morales, B; Morello, C; Moreno, J C; Morris, C; Mostafá, M; Muller, M A; Mussa, R; Navarra, G; Navarro, J L; Navas, S; Necesal, P; Nellen, L; Newman-Holmes, C; Newton, D; Nguyen Thi, T; Nierstenhoefer, N; Nitz, D; Nosek, D; Nozka, L; Oehlschläger, J; Ohnuki, T; Olinto, A; Olmos-Gilbaja, V M; Ortiz, M; Ortolani, F; Ostapchenko, S; Otero, L; Pacheco, N; Pakk Selmi-Dei, D; Palatka, M; Pallotta, J; Parente, G; Parizot, E; Parlati, S; Pastor, S; Patel, M; Paul, T; Pavlidou, V; Payet, K; Pech, M; Pekala, J; Pelayo, R; Pepe, I M; Perrone, L; Petrera, S; Petrinca, P; Petrov, Y; Pham Ngoc, Diep; Pham Ngoc, Dong; Pham Thi, T N; Pichel, A; Piegaia, R; Pierog, T; Pimenta, M; Pinto, T; Pirronello, V; Pisanti, O; Platino, M; Pochon, J; Privitera, P; Prouza, M; Quel, E J; Rautenberg, J; Redondo, A; Reucroft, S; Revenu, B; Rezende, F A S; Ridky, J; Riggi, S; Risse, M; Rivière, C; Rizi, V; Roberts, M; Robledo, C; Rodriguez, G; Rodríguez Frías, D; Rodriguez Martino, J; Rodriguez Rojo, J; Rodriguez-Cabo, I; Ros, G; Rosado, J; Roth, M; Rouillé-d'Orfeuil, B; Roulet, E; Rovero, A C; Salamida, F; Salazar, H; Salina, G; Sánchez, F; Santander, M; Santo, C E; Santos, E M; Sarazin, F; Sarkar, S; Sato, R; Scherini, V; Schieler, H; Schmidt, A; Schmidt, F; Schmidt, T; Scholten, O; Schovánek, P; Schüssler, F; Sciutto, S J; Scuderi, M; Segreto, A; Semikoz, D; Settimo, M; Shellard, R C; Sidelnik, I; Siffert, B B; Sigl, G; Smetniansky De Grande, N; Smiałkowski, A; Smída, R; Smith, A G K; Smith, B E; Snow, G R; Sokolsky, P; Sommers, P; Sorokin, J; Spinka, H; Squartini, R; Strazzeri, E; Stutz, A; Suarez, F; Suomijärvi, T; Supanitsky, A D; Sutherland, M S; Swain, J; Szadkowski, Z; Takahashi, J; Tamashiro, A; Tamburro, A; Taşcău, O; Tcaciuc, R; Thomas, D; Ticona, R; Tiffenberg, J; Timmermans, C; Tkaczyk, W; Todero Peixoto, C J; Tomé, B; Tonachini, A; Torres, I; Torresi, D; Travnicek, P; Tripathi, A; Tristram, G; Tscherniakhovski, D; Tueros, M; Tunnicliffe, V; Ulrich, R; Unger, M; Urban, M; Valdés Galicia, J F; Valiño, I; Valore, L; van den Berg, A M; van Elewyck, V; Vázquez, R A; Veberic, D; Veiga, A; Velarde, A; Venters, T; Verzi, V; Videla, M; Villaseñor, L; Vorobiov, S; Voyvodic, L; Wahlberg, H; Wainberg, O; Walker, P; Warner, D; Watson, A A; Westerhoff, S; Wieczorek, G; Wiencke, L; Wilczyńska, B; Wilczyński, H; Wileman, C; Winnick, M G; Wu, H; Wundheiler, B; Yamamoto, T; Younk, P; Zas, E; Zavrtanik, D; Zavrtanik, M; Zech, A; Zepeda, A; Ziolkowski, M

    2008-05-30

    The surface detector array of the Pierre Auger Observatory is sensitive to Earth-skimming tau neutrinos that interact in Earth's crust. Tau leptons from nu(tau) charged-current interactions can emerge and decay in the atmosphere to produce a nearly horizontal shower with a significant electromagnetic component. The data collected between 1 January 2004 and 31 August 2007 are used to place an upper limit on the diffuse flux of nu(tau) at EeV energies. Assuming an E(nu)(-2) differential energy spectrum the limit set at 90% C.L. is E(nu)(2)dN(nu)(tau)/dE(nu)<1.3 x 10(-7) GeV cm(-2) s(-1) sr(-1) in the energy range 2 x 10(17) eV< E(nu)< 2 x 10(19) eV.

  9. Space Based Gravitational Wave Observatories (SGOs)

    NASA Technical Reports Server (NTRS)

    Livas, Jeff

    2014-01-01

    Space-based Gravitational-wave Observatories (SGOs) will enable the systematic study of the frequency band from 0.0001 - 1 Hz of gravitational waves, where a rich array of astrophysical sources is expected. ESA has selected The Gravitational Universe as the science theme for the L3 mission opportunity with a nominal launch date in 2034. This will be at a minimum 15 years after ground-based detectors and pulsar timing arrays announce their first detections and at least 18 years after the LISA Pathfinder Mission will have demonstrated key technologies in a dedicated space mission. It is therefore important to develop mission concepts that can take advantage of the momentum in the field and the investment in both technology development and a precision measurement community on a more near-term timescale than the L3 opportunity. This talk will discuss a mission concept based on the LISA baseline that resulted from a recent mission architecture study.

  10. Molecular spectroscopy from the Kuiper Airborne Observatory

    NASA Technical Reports Server (NTRS)

    Beckwith, S.

    1985-01-01

    Interstellar and circumstellar molecules are investigated through medium-resolution infrared spectrosocpy of the vibration-rotation and pure rotational transitions. A primary goal was the construction and improvement of instrumentation for the near and middle infrared regions, wavelengths between 2 and 10 microns. The main instrument was a cooled grating spectrometer with an interchangeable detector focal plane which could be used on the Kuiper Airborne Observatory (KAO) for airborne observations, and also at ground-based facilities. Interstellar shock waves were investigated by H2 emission from the Orion Nebula, W51, and the proto-planetary nebulae CRL 2688 and CRL 618. The observations determined the physical conditions in shocked molecular gas near these objects. From these it was possible to characterize the energetic history of mass loss from both pre- and post-main sequence stars in the regions.

  11. Snowstorm at the geomagnetic observatory

    NASA Astrophysics Data System (ADS)

    Čop, R.

    2015-08-01

    The Sinji Vrh Geomagnetic Observatory (hereinafter the Observatory) is situated on Gora above Ajdovščina, a highland karst plateau, in the southwestern part of Slovenia. The Observatory operates in exceptional geological and meteorological conditions due to its location. The very first measurements at the time of initial tests showed that weather fronts induce changes in the local magnetic field. The first measurements intended to determine the value of this influence were carried out at the end of summer 2011. In 2013 the first such measurements were carried out in January. This article presents the results of these measurements, showing how the snowstorm induced changes in Earth's magnetic field.

  12. Boyden Observatory, then and now

    NASA Astrophysics Data System (ADS)

    Van Heerden, H. J.

    2008-08-01

    In this article the history of Boyden Observatory, 'the first truly international observatory', from its establishment in 1889 to the present will be discussed. There will be looked at locations, personnel, research done and discoveries made. The discussion will also include sections on the instruments used during that time, with specific emphasis on the 60-inch Boyden Rockefeller Telescope. Details about the instrument's specifications, upgrades, new equipment and role as research instrument will be examined. A final section will then be devoted to where Boyden Observatory finds itself today and where it wants to position itself in the future, specifically in terms of research and education.

  13. OSO-6 Orbiting Solar Observatory

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The description, development history, test history, and orbital performance analysis of the OSO-6 Orbiting Solar Observatory are presented. The OSO-6 Orbiting Solar Observatory was the sixth flight model of a series of scientific spacecraft designed to provide a stable platform for experiments engaged in the collection of solar and celestial radiation data. The design objective was 180 days of orbital operation. The OSO-6 has telemetered an enormous amount of very useful experiment and housekeeping data to GSFC ground stations. Observatory operation during the two-year reporting period was very successful except for some experiment instrument problems.

  14. Gamma ray detector modules

    NASA Technical Reports Server (NTRS)

    Capote, M. Albert (Inventor); Lenos, Howard A. (Inventor)

    2009-01-01

    A radiation detector assembly has a semiconductor detector array substrate of CdZnTe or CdTe, having a plurality of detector cell pads on a first surface thereof, the pads having a contact metallization and a solder barrier metallization. An interposer card has planar dimensions no larger than planar dimensions of the semiconductor detector array substrate, a plurality of interconnect pads on a first surface thereof, at least one readout semiconductor chip and at least one connector on a second surface thereof, each having planar dimensions no larger than the planar dimensions of the interposer card. Solder columns extend from contacts on the interposer first surface to the plurality of pads on the semiconductor detector array substrate first surface, the solder columns having at least one solder having a melting point or liquidus less than 120 degrees C. An encapsulant is disposed between the interposer circuit card first surface and the semiconductor detector array substrate first surface, encapsulating the solder columns, the encapsulant curing at a temperature no greater than 120 degrees C.

  15. High Altitude Observatory YBJ and ARGO Project

    NASA Astrophysics Data System (ADS)

    Tan, Y.; ARGO Collaboration

    A 5800 m2 RPC (Resistive Plate Chamber) full coverage air shower array is under construction in the YangBaJing Cosmic Ray Observatory, Tibet of China, by the ChinaItaly ARGO Collaboration. YBJ is a large flat grassland with an area 10 × 70 km2 at 4300m altitude, about 90 north west from Lhasa. Its nearby power station, asphalt road to Lhasa, passing railway (will be constructed during the coming 5 years), optical fiber link to the INTERNET, rare snow and other favourable weather conditions are well suitable for setting an Astrophysical Observatory here. The installation of a large area carpet-like detector in this peculiar site will allow one to perform an all-sky and high duty cycle study of high energy gamma rays from 100GeV to 50 TeV as well as accurate measurements on UHE cosmic rays. To insure the stable and uniform working condition of RPCs, a 104 M2 carpet hall was constructed, the RPC installation have be started in it since last November. The natural distribution and daily variation of temperature in the hall, the data concerning the performances of the installed RPCs, have been measured, the results are presented. ce

  16. Status and updates from the High Altitude Water Cherenkov (HAWC) Observatory

    NASA Astrophysics Data System (ADS)

    Baughman, B. M.

    2013-06-01

    The High Altitude Water Cherenkov Observatory (HAWC) is currently being deployed on the slopes of Volcan Sierra Negra, Puebla, Mexico. The HAWC observatory will consist of 300 Water Cherenkov Detectors totaling approximately 22,000 m of instrumented area. The water Cherenkov technique allows HAWC to have a nearly 100% duty cycle and large field of view, making the HAWC observatory an ideal instrument for the study of transient phenomena. With its large effective area, excellent angular and energy resolutions, and efficient gamma-hadron separation, HAWC will survey the TeV gamma ray sky, measure spectra of galactic sources from 1 TeV to beyond 100 TeV, and map galactic diffuse gamma ray emission. The science goals and performance of the HAWC observatory as well as how it will complement contemporaneous space and ground-based detectors will be presented.

  17. Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

    DOE PAGES

    Aab, Alexander

    2016-06-14

    The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy density is determined from the radio pulses at each observer position and is interpolated using a two dimensional functionmore » that takes into account signal asymmetries due to interference between the geomagnetic and charge excess emission components. We found that the spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy – corrected for geometrical effects – is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. Finally we find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.« less

  18. Energy estimation of cosmic rays with the Engineering Radio Array of the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Aab, A.; Abreu, P.; Aglietta, M.; Ahn, E. J.; Al Samarai, I.; Albuquerque, I. F. M.; Allekotte, I.; Allison, P.; Almela, A.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Alves Batista, R.; Ambrosio, M.; Aminaei, A.; Anastasi, G. A.; Anchordoqui, L.; Andringa, S.; Aramo, C.; Arqueros, F.; Arsene, N.; Asorey, H.; Assis, P.; Aublin, J.; Avila, G.; Awal, N.; Badescu, A. M.; Baus, C.; Beatty, J. J.; Becker, K. H.; Bellido, J. A.; Berat, C.; Bertaina, M. E.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blaess, S. G.; Blanco, A.; Blanco, M.; Blazek, J.; Bleve, C.; Blümer, H.; Boháčová, M.; Boncioli, D.; Bonifazi, C.; Borodai, N.; Brack, J.; Brancus, I.; Bretz, T.; Bridgeman, A.; Brogueira, P.; Buchholz, P.; Bueno, A.; Buitink, S.; Buscemi, M.; Caballero-Mora, K. S.; Caccianiga, B.; Caccianiga, L.; Candusso, M.; Caramete, L.; Caruso, R.; Castellina, A.; Cataldi, G.; Cazon, L.; Cester, R.; Chavez, A. G.; Chiavassa, A.; Chinellato, J. A.; Chudoba, J.; Cilmo, M.; Clay, R. W.; Cocciolo, G.; Colalillo, R.; Coleman, A.; Collica, L.; Coluccia, M. R.; Conceição, R.; Contreras, F.; Cooper, M. J.; Cordier, A.; Coutu, S.; Covault, C. E.; Cronin, J.; Dallier, R.; Daniel, B.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; de Jong, S. J.; De Mauro, G.; de Mello Neto, J. R. T.; De Mitri, I.; de Oliveira, J.; de Souza, V.; del Peral, L.; Deligny, O.; Dhital, N.; Di Giulio, C.; Di Matteo, A.; Diaz, J. C.; Díaz Castro, M. L.; Diogo, F.; Dobrigkeit, C.; Docters, W.; D'Olivo, J. C.; Dorofeev, A.; Dorosti Hasankiadeh, Q.; dos Anjos, R. C.; Dova, M. T.; Ebr, J.; Engel, R.; Erdmann, M.; Erfani, M.; Escobar, C. O.; Espadanal, J.; Etchegoyen, A.; Falcke, H.; Fang, K.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Fick, B.; Figueira, J. M.; Filevich, A.; Filipčič, A.; Fratu, O.; Freire, M. M.; Fujii, T.; García, B.; Garcia-Gamez, D.; Garcia-Pinto, D.; Gate, F.; Gemmeke, H.; Gherghel-Lascu, A.; Ghia, P. L.; Giaccari, U.; Giammarchi, M.; Giller, M.; Głas, D.; Glaser, C.; Glass, H.; Golup, G.; Gómez Berisso, M.; Gómez Vitale, P. F.; González, N.; Gookin, B.; Gordon, J.; Gorgi, A.; Gorham, P.; Gouffon, P.; Griffith, N.; Grillo, A. F.; Grubb, T. D.; Guarino, F.; Guedes, G. P.; Hampel, M. R.; Hansen, P.; Harari, D.; Harrison, T. A.; Hartmann, S.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Heimann, P.; Herve, A. E.; Hill, G. C.; Hojvat, C.; Hollon, N.; Holt, E.; Homola, P.; Hörandel, J. R.; Horvath, P.; Hrabovský, M.; Huber, D.; Huege, T.; Insolia, A.; Isar, P. G.; Jandt, I.; Jansen, S.; Jarne, C.; Johnsen, J. A.; Josebachuili, M.; Kääpä, A.; Kambeitz, O.; Kampert, K. H.; Kasper, P.; Katkov, I.; Keilhauer, B.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Krause, R.; Krohm, N.; Kuempel, D.; Kukec Mezek, G.; Kunka, N.; Kuotb Awad, A. W.; LaHurd, D.; Latronico, L.; Lauer, R.; Lauscher, M.; Lautridou, P.; Le Coz, S.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; Lopes, L.; López, R.; López Casado, A.; Louedec, K.; Lucero, A.; Malacari, M.; Mallamaci, M.; Maller, J.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, V.; Mariş, I. C.; Marsella, G.; Martello, D.; Martinez, H.; Martínez Bravo, O.; Martraire, D.; Masías Meza, J. J.; Mathes, H. J.; Mathys, S.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mayotte, E.; Mazur, P. O.; Medina, C.; Medina-Tanco, G.; Meissner, R.; Mello, V. B. B.; Melo, D.; Menshikov, A.; Messina, S.; Micheletti, M. I.; Middendorf, L.; Minaya, I. A.; Miramonti, L.; Mitrica, B.; Molina-Bueno, L.; Mollerach, S.; Montanet, F.; Morello, C.; Mostafá, M.; Moura, C. A.; Muller, M. A.; Müller, G.; Müller, S.; Navas, S.; Necesal, P.; Nellen, L.; Nelles, A.; Neuser, J.; Nguyen, P. H.; Niculescu-Oglinzanu, M.; Niechciol, M.; Niemietz, L.; Niggemann, T.; Nitz, D.; Nosek, D.; Novotny, V.; Nožka, L.; Núñez, L. A.; Ochilo, L.; Oikonomou, F.; Olinto, A.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Papenbreer, P.; Parente, G.; Parra, A.; Paul, T.; Pech, M.; PÈ©kala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Petermann, E.; Peters, C.; Petrera, S.; Petrov, Y.; Phuntsok, J.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.; Platino, M.; Plum, M.; Porcelli, A.; Porowski, C.; Prado, R. R.; Privitera, P.; Prouza, M.; Quel, E. J.; Querchfeld, S.; Quinn, S.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Reinert, D.; Revenu, B.; Ridky, J.; Risse, M.; Ristori, P.; Rizi, V.; Rodrigues de Carvalho, W.; Rodriguez Rojo, J.; Rodríguez-Frías, M. D.; Rogozin, D.; Rosado, J.; Roth, M.; Roulet, E.; Rovero, A. C.; Saffi, S. J.; Saftoiu, A.; Salazar, H.; Saleh, A.; Salesa Greus, F.; Salina, G.; Sanabria Gomez, J. D.; Sánchez, F.; Sanchez-Lucas, P.; Santos, E.; Santos, E. M.; Sarazin, F.; Sarkar, B.; Sarmento, R.; Sarmiento-Cano, C.; Sato, R.; Scarso, C.; Schauer, M.; Scherini, V.; Schieler, H.; Schmidt, D.; Scholten, O.; Schoorlemmer, H.; Schovánek, P.; Schröder, F. G.; Schulz, A.; Schulz, J.; Schumacher, J.; Sciutto, S. J.; Segreto, A.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sigl, G.; Sima, O.; Śmiałkowski, A.; Šmída, R.; Snow, G. R.; Sommers, P.; Sonntag, S.; Sorokin, J.; Squartini, R.; Srivastava, Y. N.; Stanca, D.; Stanič, S.; Stapleton, J.; Stasielak, J.; Stephan, M.; Stutz, A.; Suarez, F.; Suarez Durán, M.; Suomijärvi, T.; Supanitsky, A. D.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Taborda, O. A.; Tapia, A.; Tepe, A.; Theodoro, V. M.; Timmermans, C.; Todero Peixoto, C. J.; Toma, G.; Tomankova, L.; Tomé, B.; Tonachini, A.; Torralba Elipe, G.; Torres Machado, D.; Travnicek, P.; Trini, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van Aar, G.; van Bodegom, P.; van den Berg, A. M.; van Velzen, S.; van Vliet, A.; Varela, E.; Vargas Cárdenas, B.; Varner, G.; Vasquez, R.; Vázquez, J. R.; Vázquez, R. A.; Veberič, D.; Verzi, V.; Vicha, J.; Videla, M.; Villaseñor, L.; Vlcek, B.; Vorobiov, S.; Wahlberg, H.; Wainberg, O.; Walz, D.; Watson, A. A.; Weber, M.; Weidenhaupt, K.; Weindl, A.; Welling, C.; Werner, F.; Widom, A.; Wiencke, L.; Wilczyński, H.; Winchen, T.; Wittkowski, D.; Wundheiler, B.; Wykes, S.; Yang, L.; Yapici, T.; Yushkov, A.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zepeda, A.; Zimmermann, B.; Ziolkowski, M.; Zuccarello, F.; Pierre Auger Collaboration

    2016-06-01

    The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30-80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy—corrected for geometrical effects—is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.

  19. A performance test of a new high-surface-quality and high-sensitivity CR-39 plastic nuclear track detector - TechnoTrak

    NASA Astrophysics Data System (ADS)

    Kodaira, S.; Morishige, K.; Kawashima, H.; Kitamura, H.; Kurano, M.; Hasebe, N.; Koguchi, Y.; Shinozaki, W.; Ogura, K.

    2016-09-01

    We have studied the performance of a newly-commercialized CR-39 plastic nuclear track detector (PNTD), "TechnoTrak", in energetic heavy ion measurements. The advantages of TechnoTrak are derived from its use of a purified CR-39 monomer to improve surface quality combined with an antioxidant to improve sensitivity to low-linear-energy-transfer (LET) particles. We irradiated these detectors with various heavy ions (from protons to krypton) with various energies (30-500 MeV/u) at the heavy ion accelerator facilities in the National Institute of Radiological Sciences (NIRS). The surface roughness after chemical etching was improved to be 59% of that of the conventional high-sensitivity CR-39 detector (HARZLAS/TD-1). The detectable dynamic range of LET was found to be 3.5-600 keV/μm. The LET and charge resolutions for three ions tested ranged from 5.1% to 1.5% and 0.14 to 0.22 c.u. (charge unit), respectively, in the LET range of 17-230 keV/μm, which represents an improvement over conventional products (HARZLAS/TD-1 and BARYOTRAK). A correction factor for the angular dependence was determined for correcting the LET spectrum in an isotropic radiation field. We have demonstrated the potential of TechnoTrak, with its two key features of high surface quality and high sensitivity to low-LET particles, to improve automatic analysis protocols in radiation dosimetry and various other radiological applications.

  20. The Infrared Space Observatory (ISO)

    NASA Technical Reports Server (NTRS)

    Helou, George; Kessler, Martin F.

    1995-01-01

    ISO, scheduled to launch in 1995, will carry into orbit the most sophisticated infrared observatory of the decade. Overviews of the mission, instrument payload and scientific program are given, along with a comparison of the strengths of ISO and SOFIA.

  1. Haystack Observatory Technology Development Center

    NASA Technical Reports Server (NTRS)

    Beaudoin, Chris; Corey, Brian; Niell, Arthur; Cappallo, Roger; Whitney, Alan

    2013-01-01

    Technology development at MIT Haystack Observatory were focused on four areas in 2012: VGOS developments at GGAO; Digital backend developments and workshop; RFI compatibility at VLBI stations; Mark 6 VLBI data system development.

  2. Islamic Astronomical Instruments and Observatories

    NASA Astrophysics Data System (ADS)

    Heidarzadeh, Tofigh

    This chapter is a brief survey of astronomical instruments being used and developed in Islamic territories from the eighth to the fifteenth centuries as well as a concise account of major observatories and observational programs in this period.

  3. An astronomical observatory for Peru

    NASA Astrophysics Data System (ADS)

    del Mar, Juan Quintanilla; Sicardy, Bruno; Giraldo, Víctor Ayma; Callo, Víctor Raúl Aguilar

    2011-06-01

    Peru and France are to conclude an agreement to provide Peru with an astronomical observatory equipped with a 60-cm diameter telescope. The principal aims of this project are to establish and develop research and teaching in astronomy. Since 2004, a team of researchers from Paris Observatory has been working with the University of Cusco (UNSAAC) on the educational, technical and financial aspects of implementing this venture. During an international astronomy conference in Cusco in July 2009, the foundation stone of the future Peruvian Observatory was laid at the top of Pachatusan Mountain. UNSAAC, represented by its Rector, together with the town of Oropesa and the Cusco regional authority, undertook to make the sum of 300,000€ available to the project. An agreement between Paris Observatory and UNSAAC now enables Peruvian students to study astronomy through online teaching.

  4. Search for ultra high energy primary photons at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Colalillo, Roberta

    2016-07-01

    The Pierre Auger Observatory, located in Argentina, provides an unprecedented integrated aperture in the search for primary photons with energy above 1017 eV over a large portion of the southern sky. Such photons can be detected in principle via the air showers they initiate at such energies, using the complement of Auger Observatory detectors. We discuss the results obtained in diffuse and directional searches for primary photons in the EeV energy range.

  5. Status of the SOFIA Observatory

    NASA Technical Reports Server (NTRS)

    Roellig, Thomas L.

    2015-01-01

    The SOFIA observatory has been in routine science operations since returning in January from a 6 month-long heavy maintenance period for the aircraft and the telescope assembly. These operations include a successful 6 week deployment to the Southern hemisphere. This presentation will provide an update to the current operational status of the SOFIA observatory, concentrating on the improvements and upgrades that have been implemented since the heavy maintenance period.

  6. Performance of adaptive optics at Lick Observatory

    SciTech Connect

    Olivier, S.S.; An, J.; Avicola, K.

    1994-03-01

    A prototype adaptive optics system has been developed at Lawrence Livermore National Laboratory (LLNL) for use at Lick Observatory. This system is based on an ITEX 69-actuator continuous-surface deformable mirror, a Kodak fast-framing intensified CCD camera, and a Mercury VME board containing four Intel i860 processors. The system has been tested using natural reference stars on the 40-inch Nickel telescope at Lick Observatory yielding up to a factor of 10 increase in image peak intensity and a factor of 6 reduction in image full width at half maximum (FWHM). These results are consistent with theoretical expectations. In order to improve performance, the intensified CCD camera will be replaced by a high-quantum-efficiency low-noise fast CCD camera built for LLNL by Adaptive Optics Associates using a chip developed by Lincoln Laboratory, and the 69-actuator deformable mirror will be replaced by a 127-actuator deformable mirror developed at LLNL. With these upgrades, the system should perform well in median seeing conditions on the 120-inch Shane telescope for observing wavelengths longer than {approximately}1 {mu}m and using natural reference stars brighter than m{sub R} {approximately} 10 or using the laser currently being developed at LLNL for use at Lick Observatory to generate a sodium-layer reference star.

  7. Sofia Observatory Performance and Characterization

    NASA Technical Reports Server (NTRS)

    Temi, Pasquale; Miller, Walter; Dunham, Edward; McLean, Ian; Wolf, Jurgen; Becklin, Eric; Bida, Tom; Brewster, Rick; Casey, Sean; Collins, Peter; Jakob, Holger; Killebrew, Jana; Lampater, Ulrich; Mandushev, Georgi; Marcum, Pamela; Meyer, Allan; Pfueller, Enrico; Reinacher, Andreas; Roeser, Hans-Peter; Savage, Maureen; Teufel, Stefan; Wiedemann, Manuel

    2012-01-01

    The Stratospheric Observatory for Infrared Astronomy (SOFIA) has recently concluded a set of engineering flights for Observatory performance evaluation. These in-flight opportunities have been viewed as a first comprehensive assessment of the Observatory's performance and will be used to address the development activity that is planned for 2012, as well as to identify additional Observatory upgrades. A series of 8 SOFIA Characterization And Integration (SCAI) flights have been conducted from June to December 2011. The HIPO science instrument in conjunction with the DSI Super Fast Diagnostic Camera (SFDC) have been used to evaluate pointing stability, including the image motion due to rigid-body and flexible-body telescope modes as well as possible aero-optical image motion. We report on recent improvements in pointing stability by using an Active Mass Damper system installed on Telescope Assembly. Measurements and characterization of the shear layer and cavity seeing, as well as image quality evaluation as a function of wavelength have been performed using the HIPO+FLITECAM Science Instrument configuration (FLIPO). A number of additional tests and measurements have targeted basic Observatory capabilities and requirements including, but not limited to, pointing accuracy, chopper evaluation and imager sensitivity. SCAI activities included in-flight partial Science Instrument commissioning prior to the use of the instruments as measuring engines. This paper reports on the data collected during the SCAI flights and presents current SOFIA Observatory performance and characterization.

  8. AMIGA at the Pierre Auger Observatory: The interface and control electronics of the first prototype muon counters

    NASA Astrophysics Data System (ADS)

    Videla, M.; Platino, M.; García, B.; Almela, A.; de la Vega, G.; Lucero, A.; Suarez, F.; Wainberg, O.; Sanchez, F.; Yelos, D.

    2015-08-01

    AMIGA is an enhancement of the Pierre Auger Observatory. The main goals of AMIGA are to extend the full efficiency range to lower energies of the Observatory and to measure the muon content of extensive air showers. Currently, it consists of 61 detector pairs, each one composed of a surface water-Cherenkov detector and a buried muon counter. Prototypes of the muon counter - buried at a depth of 2.25 m - were installed at each vertex of a hexagon and at its center with 750 m spacing. Each prototype has a detection area of 10 m2 segmented in 64 scintillation strips and coupled to a multi-anode PMT through optical fibers. The electronic systems of these prototypes are accessible via a service tube. An electronics interface and control board were designed to extract the data from the counter and to provide a remote control of the system. This article presents the design of the interface and control board and the results and performance during the first AMIGA acquisition period in 2012.

  9. Potential for reducing the numbers of SiPM readout surfaces of laser-processed X’tal cube PET detectors

    NASA Astrophysics Data System (ADS)

    Hirano, Yoshiyuki; Inadama, Naoko; Yoshida, Eiji; Nishikido, Fumihiko; Murayama, Hideo; Watanabe, Mitsuo; Yamaya, Taiga

    2013-03-01

    We are developing a three-dimensional (3D) position-sensitive detector with isotropic spatial resolution, the X’tal cube. Originally, our design consisted of a crystal block for which all six surfaces were covered with arrays of multi-pixel photon counters (MPPCs). In this paper, we examined the feasibility of reducing the number of surfaces on which a MPPC array must be connected with the aim of reducing the complexity of the system. We evaluated two kinds of laser-processed X’tal cubes of 3 mm and 2 mm pitch segments while varying the numbers of the 4 × 4 MPPC arrays down to two surfaces. The sub-surface laser engraving technique was used to fabricate 3D grids into a monolithic crystal block. The 3D flood histograms were obtained by the Anger-type calculation. Two figures of merit, peak-to-valley ratios and distance-to-width ratios, were used to evaluate crystal identification performance. Clear separation was obtained even in the 2-surface configuration for the 3 mm X’tal cube, and the average peak-to-valley ratios and the distance-to-width ratios were 6.7 and 2.6, respectively. Meanwhile, in the 2 mm X’tal cube, the 6-surface configuration could separate all crystals and even the 2-surface case could also, but the flood histograms were relatively shrunk in the 2-surface case, especially on planes parallel to the sensitive surfaces. However, the minimum peak-to-valley ratio did not fall below 3.9. We concluded that reducing the numbers of MPPC readout surfaces was feasible for both the 3 mm and the 2 mm X’tal cubes.

  10. Transmutation detectors

    NASA Astrophysics Data System (ADS)

    Viererbl, L.; Lahodová, Z.; Klupák, V.; Sus, F.; Kučera, J.; Kůs, P.; Marek, M.

    2011-03-01

    We have designed a new type of detectors, called transmutation detectors, which can be used primarily for neutron fluence measurement. The transmutation detector method differs from the commonly used activation detector method in evaluation of detector response after irradiation. Instead of radionuclide activity measurement using radiometric methods, the concentration of stable non-gaseous nuclides generated by transmutation in the detector is measured using analytical methods like mass spectrometry. Prospective elements and nuclear reactions for transmutation detectors are listed and initial experimental results are given. The transmutation detector method could be used primarily for long-term measurement of neutron fluence in fission nuclear reactors, but in principle it could be used for any type of radiation that can cause transmutation of nuclides in detectors. This method could also be used for measurement in accelerators or fusion reactors.

  11. Effects of reflector and crystal surface on the performance of a depth-encoding PET detector with dual-ended readout

    SciTech Connect

    Ren, Silin; Yang, Yongfeng Cherry, Simon R.

    2014-07-15

    Purpose: Depth encoding detectors are required to improve the spatial resolution and spatial resolution uniformity of small animal positron emission tomography (PET) scanners, as well as dedicated breast and brain scanners. Depth of interaction (DOI) can be measured by using dual-ended readout of lutetium oxyorthosilicate (LSO) scintillator arrays with position-sensitive avalanche photodiodes. Inter-crystal reflectors and crystal surface treatments play important roles in determining the performance of dual-ended detectors. In this paper, the authors evaluated five LSO arrays made with three different intercrystal reflectors and with either polished or unpolished crystal surfaces. Methods: The crystal size in all arrays was 1.5 mm, which is typical of the detector size used in small animal and dedicated breast scanners. The LSO arrays were measured with dual-ended readout and were compared in terms of flood histogram, energy resolution, and DOI resolution performance. Results: The four arrays using enhanced specular reflector (ESR) and Toray reflector provided similar quality flood histograms and the array using Crystal Wrap reflector gave the worst flood histogram. The two arrays using ESR reflector provided the best energy resolution and the array using Crystal Wrap reflector yielded the worst energy resolution. All arrays except the polished ESR array provided good DOI resolution ranging from 1.9 mm to 2.9 mm. DOI resolution improved as the gradient in light collection efficiency with depth (GLCED) increased. The geometric mean energies were also calculated for these dual-ended readout detectors as an alternative to the conventional summed total energy. It was shown that the geometric mean energy is advantageous in that it provides more uniform photopeak amplitude at different depths for arrays with high GLCED, and is beneficial in event selection by allowing a fixed energy window independent of depth. A new method of DOI calculation that improved the linearity

  12. The Carl Sagan solar and stellar observatories as remote observatories

    NASA Astrophysics Data System (ADS)

    Saucedo-Morales, J.; Loera-Gonzalez, P.

    In this work we summarize recent efforts made by the University of Sonora, with the goal of expanding the capability for remote operation of the Carl Sagan Solar and Stellar Observatories, as well as the first steps that have been taken in order to achieve autonomous robotic operation in the near future. The solar observatory was established in 2007 on the university campus by our late colleague A. Sánchez-Ibarra. It consists of four solar telescopes mounted on a single equatorial mount. On the other hand, the stellar observatory, which saw the first light on 16 February 2010, is located 21 km away from Hermosillo, Sonora at the site of the School of Agriculture of the University of Sonora. Both observatories can now be remotely controlled, and to some extent are able to operate autonomously. In this paper we discuss how this has been accomplished in terms of the use of software as well as the instruments under control. We also briefly discuss the main scientific and educational objectives, the future plans to improve the control software and to construct an autonomous observatory on a mountain site, as well as the opportunities for collaborations.

  13. Detector absorptivity measuring method and apparatus

    NASA Technical Reports Server (NTRS)

    Sheets, R. E. (Inventor)

    1976-01-01

    A method and apparatus for measuring the absorptivity of a radiation detector by making the detector an integral part of a cavity radiometer are described. By substituting the detector for the surface of the cavity upon which the radiation first impinges a comparison is made between the quantity of radiation incident upon the detector and the quantity reflected from the detector. The difference between the two is a measurement of the amount of radiation absorbed by the detector.

  14. Gamma-Ray Astronomy with the Hawc Observatory

    NASA Astrophysics Data System (ADS)

    Lauer, Robert J.

    2014-03-01

    The High Altitude Water Cherenkov (HAWC) Observatory is a wide field-of-view gamma-ray detector, sensitive to primary energies between 50 GeV and 100 TeV. The array is being built at an altitude of 4,100 m on the Sierra Negra volcano in Puebla, Mexico. With a duty cycle close to 100% and a daily coverage of 8 sr of the sky above it, HAWC is ideally suited to detect bright transient events at TeV energies such as gamma-ray bursts or flares from active galactic nuclei. The array will provide an unbiased survey of gamma-ray sources at energies above 100 GeV and probe the origins of astrophysical photon emission at the highest energies. The modular design of HAWC made it possible to start data taking in September 2012 with a partial array. Operation continues while the number of water Cherenkov detectors is growing, which allowed a smooth transition to full scientific operation with 111 detectors in August 2013. The completion of the full array with 300 detectors is planned for the summer of 2014. In these proceedings, we will give an overview of the status and performance of the HAWC observatory and discuss observation strategies for various gamma-ray phenomena.

  15. Neutrino Observations from the Sudbury Neutrino Observatory

    DOE R&D Accomplishments Database

    Q. R. Ahmad, R. C. Allen, T. C. Andersen, J. D. Anglin, G. Bühler, J. C. Barton, E. W. Beier, M. Bercovitch, J. Bigu, S. Biller, R. A. Black, I. Blevis, R. J. Boardman, J. Boger, E. Bonvin, M. G. Boulay, M. G. Bowler, T. J. Bowles, S. J. Brice, M. C. Browne, T. V. Bullard, T. H. Burritt, K. Cameron, J. Cameron, Y. D. Chan, M. Chen, H. H. Chen, X. Chen, M. C. Chon, B. T. Cleveland, E. T. H. Clifford, J. H. M. Cowan, D. F. Cowen, G. A. Cox, Y. Dai, X. Dai, F. Dalnoki-Veress, W. F. Davidson, P. J. Doe, G. Doucas, M. R. Dragowsky, C. A. Duba, F. A. Duncan, J. Dunmore, E. D. Earle, S. R. Elliott, H. C. Evans, G. T. Ewan, J. Farine, H. Fergani, A. P. Ferraris, R. J. Ford, M. M. Fowler, K. Frame, E. D. Frank, W. Frati, J. V. Germani, S. Gil, A. Goldschmidt, D. R. Grant, R. L. Hahn, A. L. Hallin, E. D. Hallman, A. Hamer, A. A. Hamian, R. U. Haq, C. K. Hargrove, P. J. Harvey, R. Hazama, R. Heaton, K. M. Heeger, W. J. Heintzelman, J. Heise, R. L. Helmer, J. D. Hepburn, H. Heron, J. Hewett, A. Hime, M. Howe, J. G. Hykawy, M. C. P. Isaac, P. Jagam, N. A. Jelley, C. Jillings, G. Jonkmans, J. Karn, P. T. Keener, K. Kirch, J. R. Klein, A. B. Knox, R. J. Komar, R. Kouzes, T. Kutter, C. C. M. Kyba, J. Law, I. T. Lawson, M. Lay, H. W. Lee, K. T. Lesko, J. R. Leslie, I. Levine, W. Locke, M. M. Lowry, S. Luoma, J. Lyon, S. Majerus, H. B. Mak, A. D. Marino, N. McCauley, A. B. McDonald, D. S. McDonald, K. McFarlane, G. McGregor, W. McLatchie, R. Meijer Drees, H. Mes, C. Mifflin, G. G. Miller, G. Milton, B. A. Moffat, M. Moorhead, C. W. Nally, M. S. Neubauer, F. M. Newcomer, H. S. Ng, A. J. Noble, E. B. Norman, V. M. Novikov, M. O'Neill, C. E. Okada, R. W. Ollerhead, M. Omori, J. L. Orrell, S. M. Oser, A. W. P. Poon, T. J. Radcliffe, A. Roberge, B. C. Robertson, R. G. H. Robertson, J. K. Rowley, V. L. Rusu, E. Saettler, K. K. Schaffer, A. Schuelke, M. H. Schwendener, H. Seifert, M. Shatkay, J. J. Simpson, D. Sinclair, P. Skensved, A. R. Smith, M. W. E. Smith, N. Starinsky, T. D. Steiger, R. G. Stokstad, R. S. Storey, B. Sur, R. Tafirout, N. Tagg, N. W. Tanner, R. K. Taplin, M. Thorman, P. Thornewell, P. T. Trent, Y. I. Tserkovnyak, R. Van Berg, R. G. Van de Water, C. J. Virtue, C. E. Waltham, J.-X. Wang, D. L. Wark, N. West, J. B. Wilhelmy, J. F. Wilkerson, J. Wilson, P. Wittich, J. M. Wouters, and M. Yeh

    2001-09-24

    The Sudbury Neutrino Observatory (SNO) is a water imaging Cherenkov detector. Its usage of 1000 metric tons of D{sub 2}O as target allows the SNO detector to make a solar-model independent test of the neutrino oscillation hypothesis by simultaneously measuring the solar {nu}{sub e} flux and the total flux of all active neutrino species. Solar neutrinos from the decay of {sup 8}B have been detected at SNO by the charged-current (CC) interaction on the deuteron and by the elastic scattering (ES) of electrons. While the CC reaction is sensitive exclusively to {nu}{sub e}, the ES reaction also has a small sensitivity to {nu}{sub {mu}} and {nu}{sub {tau}}. In this paper, recent solar neutrino results from the SNO experiment are presented. It is demonstrated that the solar flux from {sup 8}B decay as measured from the ES reaction rate under the no-oscillation assumption is consistent with the high precision ES measurement by the Super-Kamiokande experiment. The {nu}{sub e} flux deduced from the CC reaction rate in SNO differs from the Super-Kamiokande ES results by 3.3{sigma}. This is evidence for an active neutrino component, in additional to {nu}{sub e}, in the solar neutrino flux. These results also allow the first experimental determination of the total active {sup 8}B neutrino flux from the Sun, and is found to be in good agreement with solar model predictions.

  16. High Energy Astrophysics with the HAWC Observatory

    NASA Astrophysics Data System (ADS)

    Weisgarber, Thomas

    2014-08-01

    The High Altitude Water Cherenkov (HAWC) Observatory detects astrophysical gamma rays and cosmic rays in the energy range from 100 GeV to 100 TeV. Located at an elevation of 4100 meters on the slopes of Sierra Negra in the Mexican state of Puebla, HAWC comprises an array of 300 water Cherenkov tanks covering an area of 22000 square meters and is scheduled for completion in 2014. Using 1200 upward-facing photomultiplier tubes distributed throughout the tanks, HAWC measures the Cherenkov radiation generated by air-shower particles, from which the direction and energy of the primary particle may be determined. The detector has been taking data as a partial array for more than a year. I will highlight cosmic-ray and gamma-ray observations from this initial data set, including measurements of the cosmic-ray anisotropy and searches for transient sources. I will also discuss the expected contributions of HAWC to gamma-ray science as the detector enters full operation in the coming year.

  17. Understanding the SNO+ Detector

    NASA Astrophysics Data System (ADS)

    Kamdin, K.

    SNO+, a large liquid scintillator experiment, is the successor of the Sudbury Neutrino Observatory (SNO) experiment. The scintillator volume will be loaded with large quantities of 130Te, an isotope that undergoes double beta decay, in order to search for neutrinoless double beta decay. In addition to this search, SNO+ has a broad physics program due to its sensitivity to solar and supernova neutrinos, as well as reactor and geo anti-neutrinos. SNO+ can also place competitive limits on certain modes of invisible nucleon decay during its first phase. The detector is currently undergoing commissioning in preparation for its first phase, in which the detector is filled with ultra pure water. This will be followed by a pure scintillator phase, and then a Tellurium-loaded scintillator phase to search for neutrinoless double beta decay. Here we present the work done to model detector aging, which was first observed during SNO. The aging was found to reduce the optical response of the detector. We also describe early results from electronics calibration of SNO+.

  18. Understanding the SNO+ Detector

    SciTech Connect

    Kamdin, K.

    2015-03-24

    SNO+, a large liquid scintillator experiment, is the successor of the Sudbury Neutrino Observatory (SNO) experiment. The scintillator volume will be loaded with large quantities of 130Te, an isotope that undergoes double beta decay, in order to search for neutrinoless double beta decay. In addition to this search, SNO+ has a broad physics program due to its sensitivity to solar and supernova neutrinos, as well as reactor and geo anti-neutrinos. SNO+ can also place competitive limits on certain modes of invisible nucleon decay during its first phase. The detector is currently undergoing commissioning in preparation for its first phase, in which the detector is filled with ultra pure water. This will be followed by a pure scintillator phase, and then a Tellurium-loaded scintillator phase to search for neutrinoless double beta decay. Here we present the work done to model detector aging, which was first observed during SNO. The aging was found to reduce the optical response of the detector. We also describe early results from electronics calibration of SNO+.

  19. Understanding the SNO+ Detector

    DOE PAGES

    Kamdin, K.

    2015-03-24

    SNO+, a large liquid scintillator experiment, is the successor of the Sudbury Neutrino Observatory (SNO) experiment. The scintillator volume will be loaded with large quantities of 130Te, an isotope that undergoes double beta decay, in order to search for neutrinoless double beta decay. In addition to this search, SNO+ has a broad physics program due to its sensitivity to solar and supernova neutrinos, as well as reactor and geo anti-neutrinos. SNO+ can also place competitive limits on certain modes of invisible nucleon decay during its first phase. The detector is currently undergoing commissioning in preparation for its first phase, inmore » which the detector is filled with ultra pure water. This will be followed by a pure scintillator phase, and then a Tellurium-loaded scintillator phase to search for neutrinoless double beta decay. Here we present the work done to model detector aging, which was first observed during SNO. The aging was found to reduce the optical response of the detector. We also describe early results from electronics calibration of SNO+.« less

  20. Phonon magnification and the Gaussian curvature of the slowness surface in anisotropic media: Detector shape effects with application to GaAs

    NASA Astrophysics Data System (ADS)

    Lax, M.; Narayanamurti, V.

    1980-11-01

    A new short derivation is given for the magnification of photons, phonons, and other wave phenomena in anisotropic media. The results, when specialized to the phonon case, agree with those of Maris and of Philip and Viswanathan. At nondegenerate points the magnification is shown, regardless of the nature of the wave phenomenon, to be expressible in terms of the Gaussian curvature K at the wave vector q--> of the surface ω(q-->)=ω. A representation of K, free of surface coordinates, is given as the cofactor of a 3×3 curvature tensor. The curvature tensor contains information beyond the Jacobian, such as the two principal magnifications for a given mode. Along degenerate directions (such as the [100] direction in cubic crystals) the results, even in the infinitesimal limit, are sensitive to the shape of the detector. Explicit expressions for circular, rectangular and square detectors are given and applied to the case of ballistic phonons in GaAs. Numerical calculation of finite aperture effects indicates significant qualitative as well as quantitative differences with infinitesimal aperture results.

  1. India-based neutrino observatory (INO): Physics reach and status report

    SciTech Connect

    Indumathi, D.

    2015-07-15

    We present a review of the physics reach and current status of the proposed India-based Neutrino Observatory (INO). We briefly outline details of the INO location and the present status of detector development. We then present the physics goals and simulation studies of the main detector, the magnetised Iron Calorimeter (ICAL) detector, to be housed in INO. The ICAL detector would make precision measurements of neutrino oscillation parameters with atmospheric neutrinos including a measurement of the neutrino mass hierarchy. Additional synergies with other experiments due to the complete insensitivity of ICAL to the CP phase are also discussed.

  2. GEOSCOPE Observatory Recent Developments

    NASA Astrophysics Data System (ADS)

    Leroy, N.; Pardo, C.; Bonaime, S.; Stutzmann, E.; Maggi, A.

    2010-12-01

    The GEOSCOPE observatory consists of a global seismic network and a data center. The 31 GEOSCOPE stations are installed in 19 countries, across all continents and on islands throughout the oceans. They are equipped with three component very broadband seismometers (STS1 or STS2) and 24 or 26 bit digitizers, as required by the Federation of Seismic Digital Network (FDSN). In most stations, a pressure gauge and a thermometer are also installed. Currently, 23 stations send data in real or near real time to GEOSCOPE Data Center and tsunami warning centers. In 2009, two stations (SSB and PPTF) have been equipped with warpless base plates. Analysis of one year of data shows that the new installation decreases long period noise (20s to 1000s) by 10 db on horizontal components. SSB is now rated in the top ten long period stations for horizontal components according to the LDEO criteria. In 2010, Stations COYC, PEL and RER have been upgraded with Q330HR, Metrozet electronics and warpless base plates. They have been calibrated with the calibration table CT-EW1 and the software jSeisCal and Calex-EW. Aluminum jars are now installed instead of glass bells. A vacuum of 100 mbars is applied in the jars which improves thermal insulation of the seismometers and reduces moisture and long-term corrosion in the sensor. A new station RODM has just been installed in Rodrigues Island in Mauritius with standard Geoscope STS2 setup: STS2 seismometer on a granite base plate and covered by cooking pot and thermal insulation, it is connected to Q330HR digitizer, active lightning protection, Seiscomp PC and real-time internet connection. Continuous data of all stations are collected in real time or with a delay by the GEOSCOPE Data Center in Paris where they are validated, archived and made available to the international scientific community. Data are freely available to users by different interfaces according data types (see : http://geoscope.ipgp.fr) - Continuous data in real time coming

  3. Development of solar tower observatories

    NASA Astrophysics Data System (ADS)

    Wolfschmidt, Gudrun

    Because the horizontal solar telescope, the Snow Telescope in Yerkes Observatory, was affected by air-currents from the warmed-up soil, George Ellery Hale had the idea of a tower telescope. In 1904, the 60-foot tower in Mt. Wilson was ready, in 1908 the 150-foot tower was built with the help of the Carnegie foundation. After World War I, Germany made heavy efforts to regain its former strong position in the field of science. Already in December 1919 - after the spectacular result of the English eclipse expedition in October 1919 - Erwin Finlay-Freundlich started a successful fund raising (“Einstein-Stiftungrdquo;) among German industrialists. The company Zeiss in Jena was responsible for the instrumentation of the 20-m solar tower, built in 1920-22. The optical design of the Einstein Tower in respect to light intensity surpassed even the Mt. Wilson solar observatory. Also abroad solar tower observatories were built in the 1920s: Utrecht,The Netherlands (1922), Canberra, Australia (1924), Arcetri, Italy (1926), Pasadena, California (1926) and Tokyo, Japan (1928). In the thirties, solar physics became important because of the solar maximum in 1938 and the new observational possibilities created by Bernard Lyot. At the end of the 1930s, Karl-Otto Kiepenheuer proposed to establish a solar tower observatory on Wendelstein in order to improve the predictions of radio interference by observing sunspots. By stressing the importance of the solar research for war efforts, Otto Heckmann of Göttingen observatory finally succeeded in winning the “Reichsluftfahrtministerium” to finance several solar observatories, like Wendelstein, Hainberg/Göttingen, Kanzelhöhe/Villach, and Schauinsland/Freiburg. Solar astronomy profited by the foundation of the new observatories - four of them existed still after the war. Abroad only the solar observatories of Oxford (1935) and the 50 foot tower of the McMath-Hulbert Observatory, University of Michigan (1936) should be mentioned. Only

  4. Probing Dark Energy via Neutrino and Supernova Observatories

    SciTech Connect

    Hall, Lawrence; Hall, Lawrence J.; Murayama, Hitoshi; Papucci, Michele; Perez, Gilad

    2006-07-10

    A novel method for extracting cosmological evolution parameters is proposed, using a probe other than light: future observations of the diffuse anti-neutrino flux emitted from core-collapse supernovae (SNe), combined with the SN rate extracted from future SN surveys. The relic SN neutrino differential flux can be extracted by using future neutrino detectors such as Gadolinium-enriched, megaton, water detectors or 100-kiloton detectors of liquid Argon or liquid scintillator. The core-collapse SN rate can be reconstructed from direct observation of SN explosions using future precision observatories. Our method, by itself, cannot compete with the accuracy of the optical-based measurements but may serve as an important consistency check as well as a source of complementary information. The proposal does not require construction of a dedicated experiment, but rather relies on future experiments proposed for other purposes.

  5. Observatory Bibliographies as Research Tools

    NASA Astrophysics Data System (ADS)

    Rots, Arnold H.; Winkelman, S. L.

    2013-01-01

    Traditionally, observatory bibliographies were maintained to provide insight in how successful a observatory is as measured by its prominence in the (refereed) literature. When we set up the bibliographic database for the Chandra X-ray Observatory (http://cxc.harvard.edu/cgi-gen/cda/bibliography) as part of the Chandra Data Archive ((http://cxc.harvard.edu/cda/), very early in the mission, our objective was to make it primarily a useful tool for our user community. To achieve this we are: (1) casting a very wide net in collecting Chandra-related publications; (2) including for each literature reference in the database a wealth of metadata that is useful for the users; and (3) providing specific links between the articles and the datasets in the archive that they use. As a result our users are able to browse the literature and the data archive simultaneously. As an added bonus, the rich metadata content and data links have also allowed us to assemble more meaningful statistics about the scientific efficacy of the observatory. In all this we collaborate closely with the Astrophysics Data System (ADS). Among the plans for future enhancement are the inclusion of press releases and the Chandra image gallery, linking with ADS semantic searching tools, full-text metadata mining, and linking with other observatories' bibliographies. This work is supported by NASA contract NAS8-03060 (CXC) and depends critically on the services provided by the ADS.

  6. Scientific verification of High Altitude Water Cherenkov observatory

    NASA Astrophysics Data System (ADS)

    Marinelli, Antonio; Sparks, Kathryne; Alfaro, Ruben; González, María Magdalena; Patricelli, Barbara; Fraija, Nissim

    2014-04-01

    The High Altitude Water Cherenkov (HAWC) observatory is a TeV gamma-ray and cosmic-ray detector currently under construction at an altitude of 4100 m close to volcano Sierra Negra in the state of Puebla, Mexico. The HAWC [1] observatory is an extensive air-shower array composed of 300 optically isolated water Cherenkov detectors (WCDs). Each WCD contains ~200,000 l of filtered water and four upward-facing photomultiplier tubes. In Fall 2014, when the HAWC observatory will reach an area of 22,000 m2, the sensitivity will be 15 times higher than its predecessor Milagro [2]. Since September 2012, more than 30 WCDs have been instrumented and taking data. This first commissioning phase has been crucial for the verification of the data acquisition and event reconstruction algorithms. Moreover, with the increasing number of instrumented WCDs, it is important to verify the data taken with different configuration geometries. In this work we present a comparison between Monte Carlo simulation and data recorded by the experiment during 24 h of live time between 14 and 15 April of 2013 when 29 WCDs were active.

  7. Australian network of magnetic observatories

    NASA Astrophysics Data System (ADS)

    Barton, C. E.

    Six magnetic observatories are presently operated by the Australian Bureau of Mineral Resources, Geology and Geophysics (BMR), with assistance from various other organizations. Variometer recordings are made of three or more elements of the field at minute intervals, and absolute measurements are made weekly. There are four observatories on the continent (Canberra, Gnangara, Charters Towers, and Learmonth), one on Macquarie Island, and one at Mawson Station in eastern Antarctica (Figure 1). In addition, semiweekly absolute observations of the field (D, H, and F) are made at the other two permanent Australian Antarctic bases (Casey and Davis). A three-axis fluxgate magnetometer (EDA Electronics, Toronto , Canada) is operated independently by the Upper Atmosphere Physics group at Davis. Monthly mean values, K indices, and information about magnetic disturbances are published monthly in the BMR Geophysical Observatory Report.

  8. Environmental Observatories and Hydrologic Modeling

    NASA Astrophysics Data System (ADS)

    Hooper, R. P.; Duncan, J. M.

    2006-12-01

    During the past several years, the environmental sciences community has been attempting to design large- scale obsevatories that will transform the science. A watershed-based observatory has emerged as an effective landscape unit for a broad range of environmental sciences and engineering. For an effective observatory, modeling is a central requirement because models are precise statements of the hypothesized conceptual organization of watersheds and of the processes believed to be controlling hydrology of the watershed. Furthermore, models can serve to determine the value of existing data and the incremental value of any additional data to be collected. Given limited resources, such valuation is mandatory for an objective design of an observatory. Modeling is one part of a "digital watershed" that must be constructed for any observatory, a concept that has been developed by the CUAHSI Hydrologic Information Systems project. A digital watershed has three functions. First, it permits assembly of time series (such as stream discharge or precipitation measurements), static spatial coverages (such as topography), and dynamic fields (such as precipitation radar and other remotely sensed data). Second, based upon this common data description, a digital observatory permits multiple conceptualizations of the observatory to be created and to be stored. These conceptualizations could range from lumped box-and-arrow watershed models, to semi-distributed topographically based models, to three-dimensional finite element models. Finally, each conceptualization can lead to multiple models--that is, a set of equations that quantitatively describe hydrologic (or biogeochemical or geomorphologic) processes through libraries of tools that can be linked as workflow sequences. The advances in cyberinfrastructure that allow the storage of multiple conceptualizations and multiple model formulations of these conceptualizations promise to accelerate advances in environmental science both

  9. SU-C-201-01: Investigation of the Effects of Scintillator Surface Treatment On Light Output Measurements with SiPM Detectors

    SciTech Connect

    Valenciaga, Y; Prout, D; Chatziioannou, A

    2015-06-15

    Purpose: To examine the effect of different scintillator surface treatments (BGO crystals) on the fraction of scintillation photons that exit the crystal and reach the photodetector (SiPM). Methods: Positron Emission Tomography is based on the detection of light that exits scintillator crystals, after annihilation photons deposit energy inside these crystals. A considerable fraction of the scintillation light gets trapped or absorbed after going through multiple internal reflections on the interfaces surrounding the crystals. BGO scintillator crystals generate considerably less scintillation light than crystals made of LSO and its variants. Therefore, it is crucial that the small amount of light produced by BGO exits towards the light detector. The surface treatment of scintillator crystals is among the factors affecting the ability of scintillation light to reach the detectors. In this study, we analyze the effect of different crystal surface treatments on the fraction of scintillation light that is detected by the solid state photodetector (SiPM), once energy is deposited inside a BGO crystal. Simulations were performed by a Monte Carlo based software named GATE, and validated by measurements from individual BGO crystals coupled to Philips digital-SiPM sensor (DPC-3200). Results: The results showed an increment in light collection of about 4 percent when only the exit face of the BGO crystal, is unpolished; compared to when all the faces are polished. However, leaving several faces unpolished caused a reduction of at least 10 percent of light output when the interaction occurs as far from the exit face of the crystal as possible compared to when it occurs very close to the exit face. Conclusion: This work demonstrates the advantages on light collection from leaving unpolished the exit face of BGO crystals. The configuration with best light output will be used to obtain flood images from BGO crystal arrays coupled to SiPM sensors.

  10. The Educational Mission of the PSU/Greenbush Astrophysical Observatory

    NASA Astrophysics Data System (ADS)

    Kuehn, D. M.

    1996-09-01

    In a cooperative agreement between Pittsburg State University (PSU) and the Southeast Education Service Center (ESC) at Greenbush, KS, the PSU/Greenbush Astrophysical Observatory has been constructed. The main instrument is a 61 cm f/15 Cassegrainian telescope. Currently in house are a Boller and Chivens spectrograph, a custom-built spectrophotometer, and a single-channel photoelectric photometer. The spectrograph has been modified for use with a CCD detector. The observatory's construction was funded by a local telephone cooperative and thirty-four local school districts. Programs for elementary and secondary students and teachers have been initiated; some of these having been funded by the Kansas Board of Education through the Goals 2000 program. The ESC has spent the last several years interconnecting the schools it serves for interactive distant learning (IDL) capability. The observatory will be connected to this network and the telescope will have multiple live video feeds over fiber optic cable. In addition, the telescope is completely remotely controlled with either direct interaction with a computer via mouse and keyboard or through user-independent voice recognition software. Students in classrooms will be able to perform observing projects remotely over their IDL hookup, live two-way video/audio interaction with observatory personnel. Moreover, on-site use by groups of students, teachers, and members of the general public will be encouraged.

  11. High Energy Astronomy Observatory (HEAO)

    NASA Technical Reports Server (NTRS)

    1972-01-01

    This is an artist's concept describing the High Energy Astronomy Observatory (HEAO). The HEAO project involved the launching of three unmarned scientific observatories into low Earth orbit between 1977 and 1979 to study some of the most intriguing mysteries of the universe; pulsars, black holes, neutron stars, and super nova. This concept was painted by Jack Hood of the Marshall Space Flight Center (MSFC). Hardware support for the imaging instruments was provided by American Science and Engineering. The HEAO spacecraft were built by TRW, Inc. under project management of the MSFC.

  12. The Compton Observatory Science Workshop

    NASA Technical Reports Server (NTRS)

    Shrader, Chris R. (Editor); Gehrels, Neil (Editor); Dennis, Brian (Editor)

    1992-01-01

    The Compton Observatory Science Workshop was held in Annapolis, Maryland on September 23-25, 1991. The primary purpose of the workshop was to provide a forum for the exchange of ideas and information among scientists with interests in various areas of high energy astrophysics, with emphasis on the scientific capabilities of the Compton Observatory. Early scientific results, as well as reports on in-flight instrument performance and calibrations are presented. Guest investigator data products, analysis techniques, and associated software were discussed. Scientific topics covered included active galaxies, cosmic gamma ray bursts, solar physics, pulsars, novae, supernovae, galactic binary sources, and diffuse galactic and extragalactic emission.

  13. Scientific Detectors for Astronomy 2005

    NASA Astrophysics Data System (ADS)

    Beletic, Jenna E.; Beletic, James W.; Amico, Paola

    2006-03-01

    Every three years, the leading experts in detectors for astronomy gather together to exchange information and form professional relationships. This series of meetings is entitled Scientific Detectors for Astronomy. The meeting has been held six times, with the last four publishing hardcover proceedings. Nearly all leading astronomical observatories and manufacturers attend this meeting, with participants from every continent of the world. The 2005 meeting in Taormina, Italy was attended by 127 professionals who develop and use the highest quality detectors for wavelengths from x-ray to sub-mm, with emphasis on optical and infrared detectors. The meeting consisted of overview talks, technical presentations, poster sessions and roundtable discussions. In addition, a strong cultural programme exposed the participants to the host region while fostering the enhancement of professional relationships. These proceedings capture the technical content and the spirit of the 2005 workshop. The 87 papers cover a wide range of detector technologies including CCDs, CMOS, APDs, and sub-mm detectors. There are papers on observatory status and plans, special applications, detector testing and characterization, and electronics. A special feature of these proceedings is the inclusion of pedagogical overview papers, which were written by teams of leading experts from different institutions. These proceedings are appropriate for a range of expertise levels, from undergraduates to professionals working in the field. The information presented in this book will serve as a valuable reference for many years to come. This workshop was organized by the Scientific Workshop Factory, Inc. and the INAF- Osservatorio Astrofisico di Catania. Link: http://www.springeronline.com/sgw/cda/frontpage/0,11855,5-102-22-91528896-0,00.html?changeHeader=true

  14. Tools for Coordinated Planning Between Observatories

    NASA Technical Reports Server (NTRS)

    Jones, Jeremy; Fishman, Mark; Grella, Vince; Kerbel, Uri; Maks, Lori; Misra, Dharitri; Pell, Vince; Powers, Edward I. (Technical Monitor)

    2001-01-01

    With the realization of NASA's era of great observatories, there are now more than three space-based telescopes operating in different wavebands. This situation provides astronomers with a unique opportunity to simultaneously observe with multiple observatories. Yet scheduling multiple observatories simultaneously is highly inefficient when compared to observations using only one single observatory. Thus, programs using multiple observatories are limited not due to scientific restrictions, but due to operational inefficiencies. At present, multi-observatory programs are conducted by submitting observing proposals separately to each concerned observatory. To assure that the proposed observations can be scheduled, each observatory's staff has to check that the observations are valid and meet all the constraints for their own observatory; in addition, they have to verify that the observations satisfy the constraints of the other observatories. Thus, coordinated observations require painstaking manual collaboration among the observatory staff at each observatory. Due to the lack of automated tools for coordinated observations, this process is time consuming, error-prone, and the outcome of the requests is not certain until the very end. To increase observatory operations efficiency, such manpower intensive processes need to undergo re-engineering. To overcome this critical deficiency, Goddard Space Flight Center's Advanced Architectures and Automation Branch is developing a prototype effort called the Visual Observation Layout Tool (VOLT). The main objective of the VOLT project is to provide visual tools to help automate the planning of coordinated observations by multiple astronomical observatories, as well as to increase the scheduling probability of all observations.

  15. Interdisciplinary science with large aperture detectors

    NASA Astrophysics Data System (ADS)

    Wiencke, Lawrence

    2013-06-01

    Large aperture detector systems to measure high energy cosmic rays also offer unique opportunities in other areas of science. Disciplines include geophysics such as seismic and volcanic activity, and atmospheric science ranging from clouds to lightning to aerosols to optical transients. This paper will discuss potential opportunities based on the ongoing experience of the Pierre Auger Observatory.

  16. Electromagnetic radiation detector

    DOEpatents

    Benson, Jay L.; Hansen, Gordon J.

    1976-01-01

    An electromagnetic radiation detector including a collimating window, a cathode member having a photoelectric emissive material surface angularly disposed to said window whereby radiation is impinged thereon at acute angles, an anode, separated from the cathode member by an evacuated space, for collecting photoelectrons emitted from the emissive cathode surface, and a negatively biased, high transmissive grid disposed between the cathode member and anode.

  17. Simultaneous Observation of Solar Neutrons from the International Space Station and High Mountain Observatories in Association with a Flare on July 8, 2014

    NASA Astrophysics Data System (ADS)

    Muraki, Y.; Lopez, D.; Koga, K.; Kakimoto, F.; Goka, T.; González, L. X.; Masuda, S.; Matsubara, Y.; Matsumoto, H.; Miranda, P.; Okudaira, O.; Obara, T.; Salinas, J.; Sako, T.; Shibata, S.; Ticona, R.; Tsunesada, Y.; Valdés-Galicia, J. F.; Watanabe, K.; Yamamoto, T.

    2016-04-01

    An M6.5-class flare was observed at N12E56 on the solar surface at 16:06 UT on July 8, 2014. In association with the flare, two neutron detectors located at high mountains, Mt. Sierra Negra in Mexico and Mt. Chacaltaya in Bolivia, recorded two neutron pulses, separated approximately by 30 min. Moreover, enhancements were also observed by the solar neutron detector onboard the International Space Station. We analyzed these data combined with solar images from Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory. From these we noticed that the production mechanism of neutrons cannot be explained by a single model; at least one of the enhancements may be explained by an electric field generated by the collision of magnetic loops and the other by the shock acceleration mechanism at the front side of the CME.

  18. Towards a new Mercator Observatory Control System

    NASA Astrophysics Data System (ADS)

    Pessemier, W.; Raskin, G.; Prins, S.; Saey, P.; Merges, F.; Padilla, J. P.; Van Winckel, H.; Waelkens, C.

    2010-07-01

    A new control system is currently being developed for the 1.2-meter Mercator Telescope at the Roque de Los Muchachos Observatory (La Palma, Spain). Formerly based on transputers, the new Mercator Observatory Control System (MOCS) consists of a small network of Linux computers complemented by a central industrial controller and an industrial real-time data communication network. Python is chosen as the high-level language to develop flexible yet powerful supervisory control and data acquisition (SCADA) software for the Linux computers. Specialized applications such as detector control, auto-guiding and middleware management are also integrated in the same Python software package. The industrial controller, on the other hand, is connected to the majority of the field devices and is targeted to run various control loops, some of which are real-time critical. Independently of the Linux distributed control system (DCS), this controller makes sure that high priority tasks such as the telescope motion, mirror support and hydrostatic bearing control are carried out in a reliable and safe way. A comparison is made between different controller technologies including a LabVIEW embedded system, a PROFINET Programmable Logic Controller (PLC) and motion controller, and an EtherCAT embedded PC (soft-PLC). As the latter is chosen as the primary platform for the lower level control, a substantial part of the software is being ported to the IEC 61131-3 standard programming languages. Additionally, obsolete hardware is gradually being replaced by standard industrial alternatives with fast EtherCAT communication. The use of Python as a scripting language allows a smooth migration to the final MOCS: finished parts of the new control system can readily be commissioned to replace the corresponding transputer units of the old control system with minimal downtime. In this contribution, we give an overview of the systems design, implementation details and the current status of the project.

  19. Wilbur: A Low-Cost CCD System for MDM Observatory

    NASA Astrophysics Data System (ADS)

    Metzger, Mark R.; Tonry, John L.; Luppino, Gerard A.

    1993-01-01

    We describe ``Wilbur'', a CCD camera constructed for the Michigan-Dartmouth-MIT Observatory. The camera system hardware was constructed using existing designs for the dewar and control electronics and a commercially available control computer. The requirements for new hardware design was reduced to a simple interface, allowing us to keep the cost low and produce a working system on the telescope in under three months. New software written for operation of the camera consists of several individual components which provide data acquisition from the CCD, control of the telescope, and operation of auxiliary instruments. The hardware and software are modular, giving the flexibility to operate with other existing and future detectors at the observatory. The software also provides advanced CCD readout features such as shutterless video and drift scanning, and can be operated remotely from other computers over an IP-based network.

  20. Monitoring and near-real time forecasting of landslide surface displacements using continuous GNSS observations and a combined statistical-mechanical model: the service of the French Landslide Observatory - OMIV. (Invited)

    NASA Astrophysics Data System (ADS)

    Malet, J.; Deprez, A.; Bernardie, S.; Desramaut, N.; Ulrich, P.; Masson, F.; Grandjean, G.

    2013-12-01

    The objective of this work is to present a methodology developed by the French Landslide Observatory (e.g. OMIV), a collaborative structure aiming at collecting the same type of kinematic, hydrologic and seismic observations on landslides and at disseminating the data to the scientific community (e.g. http://omiv.unistra.fr), for the near-real time characterization of surface displacements using permanent GNSS stations. In France, several GNSS receivers have been installed on active landslides (e.g. La Clapière rockslide, Avignonet and Villerville rotational slides, Super-Sauze and La Valette mudslides) since a few years. These landslides show very different displacement rates (ranging from a few centimetres to several meters per year) and different kinematic regimes (e.g. continuous displacement of nearly constant rate or succession of periods of acceleration/deceleration). For the monitoring of landslides where the required degree of accuracy is millimetric, GNSS has been mainly used through campaigns measurements as a complement to conventional geodetic methods. Permanent monitoring is still not usually performed operationally, mostly because of the cost of the stations compared to conventional deformation monitoring techniques. In addition, if GNSS measurements can reach a millimetre-level of accuracy for long observation sessions (typically 12h), their accuracy decreases with the duration of the observation sessions, and attaining a one millimetre-level accuracy requires sophisticated a posteriori data processing techniques. To acquire a very precise 3D coordinate that can be used as a reference for other monitoring techniques and to develop early-warning systems, permanent GNSS with automatic data transmission is certainly the only solution that can be used on very constraining sites with either difficult accessibility, absence of long-term stability of the slopes around the landslide, or absence of direct visibility. The objectives of this work are (1) to

  1. The National Ecological Observatory Network

    NASA Astrophysics Data System (ADS)

    Michener, W. K.

    2006-05-01

    The National Ecological Observatory Network (NEON) is a research platform designed to advance understanding of how ecosystems and organisms respond to variations in climate and changes in land use. NEON is the first long-term ecological observatory conceived as a continental-scale network; equipped with standardized sensors, cyberinfrastructure, and data-collection protocols across the network; and designed to simultaneously address a common set of research questions and support investigator-driven ecological research in all regions of the United States. The Observatory focuses on variations in climate and land use because they are primary drivers of the Nation's environmental challenges, as identified by the National Research Council--i.e., biodiversity, biogeochemical cycles, climate change, hydroecology, infectious disease, invasive species, and land use. At the broadest scale, NEON links the complexity of climate variation to the behavior of ecological systems, a core aspect of ecological complexity. At the same time, because of the complexity of the interactions among humans and ecosystems, the network design includes NEON sites in wild, managed and urban systems within climate domains. Observatory data will also be part of a national education program designed to advance ecological science literacy through new programs and activities that develop and promote scientific ways of thinking.

  2. Planetary research at Lowell Observatory

    NASA Technical Reports Server (NTRS)

    Baum, William A.

    1988-01-01

    Scientific goals include a better determination of the basic physical characteristics of cometary nuclei, a more complete understanding of the complex processes in the comae, a survey of abundances and gas/dust ratios in a large number of comets, and measurement of primordial (12)C/(13)C and (14)N/(15)N ratios. The program also includes the observation of Pluto-Charon mutual eclipses to derive dimensions. Reduction and analysis of extensive narrowband photometry of Comet Halley from Cerro Tololo Inter-American Observatory, Perth Observatory, Lowell Observatory, and Mauna Kea Observatory were completed. It was shown that the 7.4-day periodicity in the activity of Comet Halley was present from late February through at least early June 1986, but there is no conclusive evidence of periodic variability in the preperihelion data. Greatly improved NH scalelengths and lifetimes were derived from the Halley data which lead to the conclusion that the abundance of NH in comets is much higher than previously believed. Simultaneous optical and thermal infrared observations were obtained of Comet P/Temple 2 using the MKO 2.2 m telescope and the NASA IRTF. Preliminary analysis of these observations shows that the comet's nucleus is highly elongated, very dark, and quite red.

  3. The Coronal Solar Magnetism Observatory

    NASA Astrophysics Data System (ADS)

    Tomczyk, S.; Landi, E.; Zhang, J.; Lin, H.; DeLuca, E. E.

    2015-12-01

    Measurements of coronal and chromospheric magnetic fields are arguably the most important observables required for advances in our understanding of the processes responsible for coronal heating, coronal dynamics and the generation of space weather that affects communications, GPS systems, space flight, and power transmission. The Coronal Solar Magnetism Observatory (COSMO) is a proposed ground-based suite of instruments designed for routine study of coronal and chromospheric magnetic fields and their environment, and to understand the formation of coronal mass ejections (CME) and their relation to other forms of solar activity. This new facility will be operated by the High Altitude Observatory of the National Center for Atmospheric Research (HAO/NCAR) with partners at the University of Michigan, the University of Hawaii and George Mason University in support of the solar and heliospheric community. It will replace the current NCAR Mauna Loa Solar Observatory (http://mlso.hao.ucar.edu). COSMO will enhance the value of existing and new observatories on the ground and in space by providing unique and crucial observations of the global coronal and chromospheric magnetic field and its evolution. The design and current status of the COSMO will be reviewed.

  4. ISS images for Observatory protection

    NASA Astrophysics Data System (ADS)

    Sánchez de Miguel, Alejandro; Zamorano, Jaime

    2015-08-01

    Light pollution is the main factor of degradation of the astronomical quality of the sky along the history. Astronomical observatories have been monitoring how the brightness of the sky varies using photometric measures of the night sky brightness mainly at zenith. Since the sky brightness depends in other factors such as sky glow, aerosols, solar activity and the presence of celestial objects, the continuous increase of light pollution in these enclaves is difficult to trace except when it is too late.Using models of light dispersion on the atmosphere one can determine which light pollution sources are increasing the sky brightness at the observatories. The input satellite data has been provided by DMSP/OLS and SNPP/VIIRS. Unfortunately their panchromatic bands (color blinded) are not useful to detect in which extension the increase is due to the dramatic change produced by the irruption of LED technology in outdoor lighting. The only instrument in the space that is able to distinguish between the various lighting technologies are the DSLR cameras used by the astronauts onboard the ISS.Current status for some astronomical observatories that have been imaged from the ISS is presented. We are planning to send an official request to NASA with a plan to get images for the most important astronomical observatories. We ask support for this proposal by the astronomical community and especially by the US-based researchers.

  5. The gamma-ray observatory

    NASA Technical Reports Server (NTRS)

    1991-01-01

    An overview is given of the Gamma Ray Observatory (GRO) mission. Detection of gamma rays and gamma ray sources, operations using the Space Shuttle, and instruments aboard the GRO, including the Burst and Transient Source Experiment (BATSE), the Oriented Scintillation Spectrometer Experiment (OSSE), the Imaging Compton Telescope (COMPTEL), and the Energetic Gamma Ray Experiment Telescope (EGRET) are among the topics surveyed.

  6. Search for ultrahigh energy neutrinos in highly inclined events at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Abreu, P.; Aglietta, M.; Ahn, E. J.; Albuquerque, I. F. M.; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Antičić, T.; Anzalone, A.; Aramo, C.; Arganda, E.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Bäcker, T.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Bäuml, J.; Beatty, J. J.; Becker, B. R.; Becker, K. H.; Bellétoile, A.; Bellido, J. A.; Benzvi, S.; Berat, C.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Blümer, H.; Boháčová, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brogueira, P.; Brown, W. C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Burton, R. E.; Caballero-Mora, K. S.; Caramete, L.; Caruso, R.; Castellina, A.; Catalano, O.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Cheng, S. H.; Chiavassa, A.; Chinellato, J. A.; Chou, A.; Chudoba, J.; Clay, R. W.; Coluccia, M. R.; Conceição, R.; Contreras, F.; Cook, H.; Cooper, M. J.; Coppens, J.; Cordier, A.; Coutu, S.; Covault, C. E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; de Domenico, M.; de Donato, C.; de Jong, S. J.; de La Vega, G.; de Mello Junior, W. J. M.; de Mello Neto, J. R. T.; de Mitri, I.; de Souza, V.; de Vries, K. D.; Decerprit, G.; Del Peral, L.; Del Río, M.; Deligny, O.; Dembinski, H.; Dhital, N.; di Giulio, C.; Diaz, J. C.; Díaz Castro, M. L.; Diep, P. N.; Dobrigkeit, C.; Docters, W.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; Dos Anjos, J. C.; Dova, M. T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C. O.; Espadanal, J.; Etchegoyen, A.; Facal San Luis, P.; Fajardo Tapia, I.; Falcke, H.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Ferrero, A.; Fick, B.; Filevich, A.; Filipčič, A.; Fliescher, S.; Fracchiolla, C. E.; Fraenkel, E. D.; Fröhlich, U.; Fuchs, B.; Gaior, R.; Gamarra, R. F.; Gambetta, S.; García, B.; García Gámez, D.; Garcia-Pinto, D.; Gascon, A.; Gemmeke, H.; Gesterling, K.; Ghia, P. L.; Giaccari, U.; Giller, M.; Glass, H.; Gold, M. S.; Golup, G.; Gomez Albarracin, F.; Gómez Berisso, M.; Gonçalves, P.; Gonzalez, D.; Gonzalez, J. G.; Gookin, B.; Góra, D.; Gorgi, A.; Gouffon, P.; Gozzini, S. R.; Grashorn, E.; Grebe, S.; Griffith, N.; Grigat, M.; Grillo, A. F.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Guzman, A.; Hague, J. D.; Hansen, P.; Harari, D.; Harmsma, S.; Harrison, T. A.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A. E.; Hojvat, C.; Hollon, N.; Holmes, V. C.; Homola, P.; Hörandel, J. R.; Horneffer, A.; Horvath, P.; Hrabovský, M.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jarne, C.; Jiraskova, S.; Josebachuili, M.; Kadija, K.; Kampert, K. H.; Karhan, P.; Kasper, P.; Kégl, B.; Keilhauer, B.; Keivani, A.; Kelley, J. L.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D.-H.; Kotera, K.; Krohm, N.; Krömer, O.; Kruppke-Hansen, D.; Kuehn, F.; Kuempel, D.; Kulbartz, J. K.; Kunka, N.; Rosa, G.; Lachaud, C.; Lautridou, P.; Leão, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Lemiere, A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; López, R.; Lopez Agüera, A.; Louedec, K.; Lozano Bahilo, J.; Lu, L.; Lucero, A.; Ludwig, M.; Lyberis, H.; Maccarone, M. C.; Macolino, C.; Maldera, S.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, J.; Marin, V.; Maris, I. C.; Marquez Falcon, H. R.; Marsella, G.; Martello, D.; Martin, L.; Martinez, H.; Martínez Bravo, O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mazur, P. O.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Mertsch, P.; Meurer, C.; Mićanović, S.; Micheletti, M. I.; Miller, W.; Miramonti, L.; Molina-Bueno, L.; Mollerach, S.; Monasor, M.; Monnier Ragaigne, D.; Montanet, F.; Morales, B.; Morello, C.; Moreno, E.; Moreno, J. C.; Morris, C.; Mostafá, M.; Moura, C. A.; Mueller, S.; Muller, M. A.; Müller, G.; Münchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J. L.; Navas, S.; Necesal, P.; Nellen, L.; Nelles, A.; Neuser, J.; Newton, D.; Nhung, P. T.; Niemietz, L.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nožka, L.; Nyklicek, M.; Oehlschläger, J.; Olinto, A.; Oliva, P.; Olmos-Gilbaja, V. M.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Parsons, R. D.; Pastor, S.; Paul, T.; Pech, M.; Pȩkala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrinca, P.; Petrolini, A.; Petrov, Y.; Petrovic, J.; Pfendner, C.; Phan, N.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.; Platino, M.; Ponce, V. H.; Pontz, M.; Privitera, P.; Prouza, M.; Quel, E. J.; Querchfeld, S.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Revenu, B.; Ridky, J.; Riggi, S.; Risse, M.; Ristori, P.; Rivera, H.; Rizi, V.; Roberts, J.; Robledo, C.; Rodrigues de Carvalho, W.; Rodriguez, G.; Rodriguez Martino, J.; Rodriguez Rojo, J.; Rodriguez-Cabo, I.; Rodríguez-Frías, M. D.; Ros, G.; Rosado, J.; Rossler, T.; Roth, M.; Rouillé-D'Orfeuil, B.; Roulet, E.; Rovero, A. C.; Rühle, C.; Salamida, F.; Salazar, H.; Salesa Greus, F.; Salina, G.; Sánchez, F.; Santo, C. E.; Santos, E.; Santos, E. M.; Sarazin, F.; Sarkar, B.; Sarkar, S.; Sato, R.; Scharf, N.; Scherini, V.; Schieler, H.; Schiffer, P.; Schmidt, A.; Schmidt, F.; Scholten, O.; Schoorlemmer, H.; Schovancova, J.; Schovánek, P.; Schröder, F.; Schulte, S.; Schuster, D.; Sciutto, S. J.; Scuderi, M.; Segreto, A.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sidelnik, I.; Sigl, G.; Silva Lopez, H. H.; Śmiałkowski, A.; Šmída, R.; Snow, G. R.; Sommers, P.; Sorokin, J.; Spinka, H.; Squartini, R.; Stanic, S.; Stapleton, J.; Stasielak, J.; Stephan, M.; Strazzeri, E.; Stutz, A.; Suarez, F.; Suomijärvi, T.; Supanitsky, A. D.; Šuša, T.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Szuba, M.; Tamashiro, A.; Tapia, A.; Tartare, M.; Taşcău, O.; Tavera Ruiz, C. G.; Tcaciuc, R.; Tegolo, D.; Thao, N. T.; Thomas, D.; Tiffenberg, J.; Timmermans, C.; Tiwari, D. K.; Tkaczyk, W.; Todero Peixoto, C. J.; Tomé, B.; Tonachini, A.; Travnicek, P.; Tridapalli, D. B.; Tristram, G.; Trovato, E.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van den Berg, A. M.; Varela, E.; Vargas Cárdenas, B.; Vázquez, J. R.; Vázquez, R. A.; Veberič, D.; Verzi, V.; Vicha, J.; Videla, M.; Villaseñor, L.; Wahlberg, H.; Wahrlich, P.; Wainberg, O.; Walz, D.; Warner, D.; Watson, A. A.; Weber, M.; Weidenhaupt, K.; Weindl, A.; Westerhoff, S.; Whelan, B. J.; Wieczorek, G.; Wiencke, L.; Wilczyńska, B.; Wilczyński, H.; Will, M.; Williams, C.; Winchen, T.; Winnick, M. G.; Wommer, M.; Wundheiler, B.; Yamamoto, T.; Yapici, T.; Younk, P.; Yuan, G.; Yushkov, A.; Zamorano, B.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zaw, I.; Zepeda, A.; Zimbres Silva, M.; Ziolkowski, M.

    2011-12-01

    The Surface Detector of the Pierre Auger Observatory is sensitive to neutrinos of all flavors above 0.1 EeV. These interact through charged and neutral currents in the atmosphere giving rise to extensive air showers. When interacting deeply in the atmosphere at nearly horizontal incidence, neutrinos can be distinguished from regular hadronic cosmic rays by the broad time structure of their shower signals in the water-Cherenkov detectors. In this paper we present for the first time an analysis based on down-going neutrinos. We describe the search procedure, the possible sources of background, the method to compute the exposure and the associated systematic uncertainties. No candidate neutrinos have been found in data collected from 1 January 2004 to 31 May 2010. Assuming an E-2 differential energy spectrum the limit on the single-flavor neutrino is E2dN/dE<1.74×10-7GeVcm-2s-1sr-1 at 90% C.L. in the energy range 1×1017eV

  7. Norwegian Ocean Observatory Network (NOON)

    NASA Astrophysics Data System (ADS)

    Ferré, Bénédicte; Mienert, Jürgen; Winther, Svein; Hageberg, Anne; Rune Godoe, Olav; Partners, Noon

    2010-05-01

    The Norwegian Ocean Observatory Network (NOON) is led by the University of Tromsø and collaborates with the Universities of Oslo and Bergen, UniResearch, Institute of Marine Research, Christian Michelsen Research and SINTEF. It is supported by the Research Council of Norway and oil and gas (O&G) industries like Statoil to develop science, technology and new educational programs. Main topics relate to ocean climate and environment as well as marine resources offshore Norway from the northern North Atlantic to the Arctic Ocean. NOON's vision is to bring Norway to the international forefront in using cable based ocean observatory technology for marine science and management, by establishing an infrastructure that enables real-time and long term monitoring of processes and interactions between hydrosphere, geosphere and biosphere. This activity is in concert with the EU funded European Strategy Forum on Research Infrastructures (ESFRI) roadmap and European Multidisciplinary Seafloor Observation (EMSO) project to attract international leading research developments. NOON envisions developing towards a European Research Infrastructure Consortium (ERIC). Beside, the research community in Norway already possesses a considerable marine infrastructure that can expand towards an international focus for real-time multidisciplinary observations in times of rapid climate change. PIC The presently established cable-based fjord observatory, followed by the establishment of a cable-based ocean observatory network towards the Arctic from an O&G installation, will provide invaluable knowledge and experience necessary to make a successful larger cable-based observatory network at the Norwegian and Arctic margin (figure 1). Access to large quantities of real-time observation from the deep sea, including high definition video, could be used to provide the public and future recruits to science a fascinating insight into an almost unexplored part of the Earth beyond the Arctic Circle

  8. The DAMPE Neutron Detector

    NASA Astrophysics Data System (ADS)

    Yan, Zhang; Tao, Ma; Yongyi, Huang

    2016-07-01

    The first Chinese space observatory DAMPE (DArk Matter Particle Explorer) was successfully launched on Dec. 17th, 2015. One major scientific object of DAMPE is to measure electrons between 5GeV to 10TeV with excellent energy resolution (1.5% at 800GeV) to search for possible dark matter signatures. The detector consists of four subsystems: a plastic scintillator detector (PSD), a silicon-tungsten tracker (STK), a BGO calorimeter (BGO), and a neutron detector (NUD). The NUD on board DAMPE is designed to detect moderated neutrons via the boron capture of thermal neutrons in boron-doped plastics. Given the fact that hadron showers initiated in the BGO calorimeter by incident nuclei tend to be followed by significantly more neutron activities comparing to electromagnetic cascades triggered by electrons, the NUD provides an additional order of magnitude hadron rejection capability to improve the overall e/p discrimination of DAMPE up to 10 ^{5}. Preliminary analysis of the in-orbit data is given, together with comparisons to the results obtained by a detailed GEANT4 simulation of the NUD instrument.

  9. Electronically shielded solid state charged particle detector

    DOEpatents

    Balmer, D.K.; Haverty, T.W.; Nordin, C.W.; Tyree, W.H.

    1996-08-20

    An electronically shielded solid state charged particle detector system having enhanced radio frequency interference immunity includes a detector housing with a detector entrance opening for receiving the charged particles. A charged particle detector having an active surface is disposed within the housing. The active surface faces toward the detector entrance opening for providing electrical signals representative of the received charged particles when the received charged particles are applied to the active surface. A conductive layer is disposed upon the active surface. In a preferred embodiment, a nonconductive layer is disposed between the conductive layer and the active surface. The conductive layer is electrically coupled to the detector housing to provide a substantially continuous conductive electrical shield surrounding the active surface. The inner surface of the detector housing is supplemented with a radio frequency absorbing material such as ferrite. 1 fig.

  10. Electronically shielded solid state charged particle detector

    DOEpatents

    Balmer, David K.; Haverty, Thomas W.; Nordin, Carl W.; Tyree, William H.

    1996-08-20

    An electronically shielded solid state charged particle detector system having enhanced radio frequency interference immunity includes a detector housing with a detector entrance opening for receiving the charged particles. A charged particle detector having an active surface is disposed within the housing. The active surface faces toward the detector entrance opening for providing electrical signals representative of the received charged particles when the received charged particles are applied to the active surface. A conductive layer is disposed upon the active surface. In a preferred embodiment, a nonconductive layer is disposed between the conductive layer and the active surface. The conductive layer is electrically coupled to the detector housing to provide a substantially continuous conductive electrical shield surrounding the active surface. The inner surface of the detector housing is supplemented with a radio frequency absorbing material such as ferrite.

  11. The First 50 Years of Konkoly Observatory

    NASA Astrophysics Data System (ADS)

    Balazs, Lajos G.; Vargha, Magda; Zsoldos, Endre

    The second half of the 19th century experienced a revolution in astronomy. It coincided with a new start of professional astronomy in Hungary through the work of Miklós Konkoly Thege (1842-1916) who is considered as a pioneer of current astrophysical activity in our country. He played an outstanding role in organizing scientific life and institutions, too. He started observations in his newly founded Observatory at Ógyalla in 1871. Sunspots were regularly observed in the observatory from 1872. In 1874 Konkoly began regular spectroscopic observations of comets and emphasized the importance of parallel laboratory works. An important field of Konkoly's astronomical activity was the observation of surface patterns of planets, particularly that of Jupiter and Mars. Spectroscopic observations of stars were also a significant part of the activity of Ógyalla Observatory. In the last period of the Konkoly era (starting in 1899) stellar photometry became the main field of research. At the end of WW I the institute was moved to Budapest Ógyalla and started a new life based on a completely new infrastructure: “... all era are followed by a new one, with its new tasks, in which the scope of activity changes correspondingly, in which enthusiasm is mostly manifested. It was different in the forties when our nation found itself following the word of the founder of our Academy, it was different in the fifties and sixties when we have to defend our nation against foreign aggression, and it became different since the sixties when, our existence being guarantied, we also have to make an effort, beside strengthening it, to get as distinguished a position among the civilized nations as possible.”

  12. Estimation of losses in a 300 m filter cavity and quantum noise reduction in the KAGRA gravitational-wave detector

    NASA Astrophysics Data System (ADS)

    Capocasa, Eleonora; Barsuglia, Matteo; Degallaix, Jérôme; Pinard, Laurent; Straniero, Nicolas; Schnabel, Roman; Somiya, Kentaro; Aso, Yoichi; Tatsumi, Daisuke; Flaminio, Raffaele

    2016-04-01

    The sensitivity of the gravitational-wave detector KAGRA, presently under construction, will be limited by quantum noise in a large fraction of its spectrum. The most promising technique to increase the detector sensitivity is the injection of squeezed states of light, where the squeezing angle is dynamically rotated by a Fabry-Pérot filter cavity. One of the main issues in the filter cavity design and realization is the optical losses due to the mirror surface imperfections. In this work we present a study of the specifications for the mirrors to be used in a 300 m filter cavity for the KAGRA detector. A prototype of the cavity will be constructed at the National Astronomical Observatory of Japan, inside the infrastructure of the former TAMA interferometer. We also discuss the potential improvement of the KAGRA sensitivity, based on a model of various realistic sources of losses and their influence on the squeezing amplitude.

  13. SOFIA - Stratospheric Observatory for Infrared Astronomy

    NASA Technical Reports Server (NTRS)

    Kunz, Nans; Bowers, Al

    2007-01-01

    This viewgraph presentation reviews the Stratospheric Observatory for Infrared Astronomy (SOFIA). The contents include: 1) Heritage & History; 2) Level 1 Requirements; 3) Top Level Overview of the Observatory; 4) Development Challenges; and 5) Highlight Photos.

  14. SOFIA: Stratospheric Observatory for Infrared Astronomy

    NASA Technical Reports Server (NTRS)

    Becker, Eric; Kunz, Nans; Bowers, Al

    2007-01-01

    This viewgraph presentation reviews the Stratospheric Observatory for Infrared Astronomy (SOFIA). The contents include: 1) Heritage & History; 2) Level 1 Requirements; 3) Top Level Overview of the Observatory; 4) Development Challenges; and 5) Highlight Photos.

  15. Performance of photomultiplier tubes and sodium iodide scintillation detector systems

    NASA Technical Reports Server (NTRS)

    Meegan, C. A.

    1981-01-01

    The performance of photomultiplier tubes (PMT's) and scintillation detector systems incorporating 50.8 by 1.27 cm NaI (T l) crystals was investigated to determine the characteristics of the photomultiplier tubes and optimize the detector geometry for the Burst and Transient Source Experiment on the Gamma Ray Observatory. Background information on performance characteristics of PMT's and NaI (T l) detectors is provided, procedures for measurement of relevant parameters are specified, and results of these measurements are presented.

  16. Smoke Detector

    NASA Technical Reports Server (NTRS)

    1979-01-01

    In the photo, Fire Chief Jay Stout of Safety Harbor, Florida, is explaining to young Richard Davis the workings of the Honeywell smoke and fire detector which probably saved Richard's life and that of his teen-age brother. Alerted by the detector's warning, the pair were able to escape their burning home. The detector in the Davis home was one of 1,500 installed in Safety Harbor residences in a cooperative program conducted by the city and Honeywell Inc.

  17. Detecting gamma-ray bursts with the pierre auger observatory using the single particle technique

    SciTech Connect

    Allard, Denis; Parizot, E.; Bertou, Xavier; Beatty, J.; Vernois, M.Du; Nitz, D.; Rodriguez, G.

    2005-08-01

    During the past ten years, gamma-ray Bursts (GRB) have been extensively studied in the keV-MeV energy range but the higher energy emission still remains mysterious. Ground based observatories have the possibility to investigate energy range around one GeV using the ''single particle technique''. The aim of the present study is to investigate the capability of the Pierre Auger Observatory to detect the high energy emission of GRBs with such a technique. According to the detector response to photon showers around one GeV, and making reasonable assumptions about the high energy emission of GRBs, we show that the Pierre Auger Observatory is a competitive instrument for this technique, and that water tanks are very promising detectors for the single particle technique.

  18. Production and counting of uncontained sources in the Sudbury Neutrino Observatory

    SciTech Connect

    Peeters, Simon J. M.

    2011-04-27

    I describe production and distribution of uncontained sources of {sup 24}Na and {sup 222}Rn inside the Sudbury Neutrino Observatory (SNO). These unique sources provided a uniquely accurate calibration of the SNO detector of its response to neutrons, produced through photodisintegration of the deuterons in the heavy water target, and to low energy {beta}-{gamma} decays.

  19. Hybrid anode for semiconductor radiation detectors

    DOEpatents

    Yang, Ge; Bolotnikov, Aleksey E; Camarda, Guiseppe; Cui, Yonggang; Hossain, Anwar; Kim, Ki Hyun; James, Ralph B

    2013-11-19

    The present invention relates to a novel hybrid anode configuration for a radiation detector that effectively reduces the edge effect of surface defects on the internal electric field in compound semiconductor detectors by focusing the internal electric field of the detector and redirecting drifting carriers away from the side surfaces of the semiconductor toward the collection electrode(s).

  20. The Magnetic Observatory Buildings at the Royal Observatory, Cape

    NASA Astrophysics Data System (ADS)

    Glass, I. S.

    2015-10-01

    During the 1830s there arose a strong international movement, promoted by Carl Friedrich Gauss and Alexander von Humboldt, to characterise the earth's magnetic field. By 1839 the Royal Society in London, driven by Edward Sabine, had organised a "Magnetic Crusade" - the establishment of a series of magnetic and meteorological observatories around the British Empire, including New Zealand, Australia, St Helena and the Cape. This article outlines the history of the latter installation, its buildings and what became of them.

  1. A likelihood method to cross-calibrate air-shower detectors

    NASA Astrophysics Data System (ADS)

    Dembinski, Hans Peter; Kégl, Balázs; Mariş, Ioana C.; Roth, Markus; Veberič, Darko

    2016-01-01

    We present a detailed statistical treatment of the energy calibration of hybrid air-shower detectors, which combine a surface detector array and a fluorescence detector, to obtain an unbiased estimate of the calibration curve. The special features of calibration data from air showers prevent unbiased results, if a standard least-squares fit is applied to the problem. We develop a general maximum-likelihood approach, based on the detailed statistical model, to solve the problem. Our approach was developed for the Pierre Auger Observatory, but the applied principles are general and can be transferred to other air-shower experiments, even to the cross-calibration of other observables. Since our general likelihood function is expensive to compute, we derive two approximations with significantly smaller computational cost. In the recent years both have been used to calibrate data of the Pierre Auger Observatory. We demonstrate that these approximations introduce negligible bias when they are applied to simulated toy experiments, which mimic realistic experimental conditions.

  2. The Chandra X-Ray Observatory and its Role for the Study of Ionized Plasmas

    NASA Technical Reports Server (NTRS)

    Weisskopf, Martin C.

    2010-01-01

    NASA's Chandra X-Ray Observatory was launched in July of 1999. Featuring a 1000cm2-class X-ray telescope with sub-arcsecond angular resolution, the Observatory has observed targets from the solar system including the earth s moon, comets, and planets to the most distant galaxy clusters and active galactic nuclei. Capable of performing moderate energy resolution image-resolved spectroscopy using its CCD detectors, and high-resolution grating spectroscopy, the Observatory has produced, and continues to produce, valuable data and insights into the emission mechanisms of the ionized plasmas in which the X-rays originate. We present a brief overview of the Observatory to provide insight as to how to use it for your investigations. We also present an, admittedly brief and biased, overview of some of the results of investigations performed with Chandra that may be of interest to this audience.

  3. Microwave Detection of Cosmic Ray Air Showers at the Pierre Auger Observatory, an R&D Effort

    NASA Astrophysics Data System (ADS)

    Williams, Christopher; the Pierre Auger Collaboration

    The measurement of microwave emission from air showers initiated by ultra-high energy cosmic rays may open the possibility of developing a novel detection technique. This new technique possesses the advantage of the fluorescence detection technique -the reconstruction of the longitudinal shower profile -combined with a 100% duty cycle, minimal atmospheric attenuation and the use of low cost commercial equipment. Placing prototype detectors at the Auger site provides for coincidence detection of air showers using established methods, ultimately assessing the feasibility of detecting air showers through microwave radiation. Two complementary techniques are currently being pursued at the Pierre Auger Observatory. MIDAS (Microwave Detection of Air Showers), AMBER (Air-shower Microwave Bremsstrahlung Experimental Radiometer), and FDWave are prototypes for large imaging dish antennas. EASIER (Extensive Air Shower Identification using Electron Radiometer), the second technique, utilizes horn antennas located on each Auger Surface Detector station for detection of microwave emission. MIDAS is a self-triggering system while AMBER, FDWave and EASIER use the trigger from the Auger detectors to record the microwave emission. The development status and future plans for these measurements is reported.

  4. A measurement of the muon number in showers using inclined events detected at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Rodriguez, G.

    2013-06-01

    The average muon content of measured showers with zenith angles between 62∘ and 80∘ detected at the Pierre Auger Observatory is obtained as a function of shower energy using a reconstruction method specifically designed for inclined showers and the hybrid character of the detector. The reconstruction of inclined showers relies on a comparison between the measured signals at ground and reference patterns at ground level from which an overall normalization factor is obtained. Since inclined showers are dominated by muons this factor gives the relative muon size. It can be calibrated using a subsample of showers simultaneously recorded with the fluorescence detector (FD) and the surface detector (SD) which provides an independent calorimetric measurement of the energy. The muon size obtained for each shower becomes a measurement of the relative number of muons with respect to the reference distributions. The precision of the measurement is assessed using simulated events which are reconstructed using exactly the same procedure. We compare the relative number of muons versus energy as obtained to simulations. Proton simulations with QGSJETII show a factor of 2.13 ± 0.04(stat) ± 0.11(sys) at 1019eV without significant variations in the energy range explored between 4 × 1018eV to 7 × 1019eV. We find that none of the current shower models, neither for proton nor for iron primaries, are able to predict as many muons as are observed.

  5. Multi Electrode Semiconductor Detectors

    NASA Astrophysics Data System (ADS)

    Amendolia, S. R.; Batignani, G.; Bertolucci, E.; Bosisio, L.; Budinich, M.; Bradaschia, C.; Fidecaro, F.; Foà, L.; Focardi, E.; Giazotto, A.; Giorgi, M. A.; Marrocchesi, P. S.; Menzione, A.; Ristori, L.; Rolandi, L.; Scribano, A.; Stefanini, A.; Vincelli, M. L.

    1981-04-01

    Detectors with very high space resolution have been built in our laboratory and tested at CERN in order to investigate their possible use in high energy physics experiments. These detectors consist of thin layers of silicon crystals acting as ionization chambers. Thin electrodes, structured in strips or in more fancy shapes are applied to their surfaces by metal coating. The space resolution which could be reached is of the order of a few microns. An interesting feature of these solid state detectors is that they can work under very high or low external pressure or at very low temperature. The use of these detectors would strongly reduce the dimensions and the cost of high energy experiments.

  6. International Ultraviolet Explorer Observatory operations

    NASA Technical Reports Server (NTRS)

    1985-01-01

    This volume contains the final report for the International Ultraviolet Explorer IUE Observatory Operations contract. The fundamental operational objective of the International Ultraviolet Explorer (IUE) program is to translate competitively selected observing programs into IUE observations, to reduce these observations into meaningful scientific data, and then to present these data to the Guest Observer in a form amenable to the pursuit of scientific research. The IUE Observatory is the key to this objective since it is the central control and support facility for all science operations functions within the IUE Project. In carrying out the operation of this facility, a number of complex functions were provided beginning with telescope scheduling and operation, proceeding to data processing, and ending with data distribution and scientific data analysis. In support of these critical-path functions, a number of other significant activities were also provided, including scientific instrument calibration, systems analysis, and software support. Routine activities have been summarized briefly whenever possible.

  7. International ultraviolet explorer observatory operations

    NASA Technical Reports Server (NTRS)

    1986-01-01

    This volume contains the Final Report for the International Ultraviolet Explorer (IUE) Observatory Operations contract, NAS5-28787. The report summarizes the activities of the IUE Observatory over the 13-month period from November 1985 through November 1986 and is arranged in sections according to the functions specified in the Statement of Work (SOW) of the contract. In order to preserve numerical correspondence between the technical SOW elements specified by the contract and the sections of this report, project management activities (SOW element 0.0.) are reported here in Section 7, following the reports of technical SOW elements 1.0 through 6.0. Routine activities have been summarized briefly whenever possible; statistical compilations, reports, and more lengthy supplementary material are contained in the Appendices.

  8. Boscovich and the Brera Observatory .

    NASA Astrophysics Data System (ADS)

    Antonello, E.

    In the mid 18th century both theoretical and practical astronomy were cultivated in Milan by Barnabites and Jesuits. In 1763 Boscovich was appointed to the chair of mathematics of the University of Pavia in the Duchy of Milan, and the following year he designed an observatory for the Jesuit Collegium of Brera in Milan. The Specola was built in 1765 and it became quickly one of the main european observatories. We discuss the relation between Boscovich and Brera in the framework of a short biography. An account is given of the initial research activity in the Specola, of the departure of Boscovich from Milan in 1773 and his coming back just before his death.

  9. New Geophysical Observatory in Uruguay

    NASA Astrophysics Data System (ADS)

    Sanchez Bettucci, L.; Nuñez, P.; Caraballo, R. R.; Ogando, R.

    2013-05-01

    In 2011 began the installation of the first geophysical observatory in Uruguay, with the aim of developing the Geosciences. The Astronomical and Geophysical Observatory Aiguá (OAGA) is located within the Cerro Catedral Tourist Farm (-34 ° 20 '0 .89 "S/-54 ° 42 '44.72" W, h: 270m). This has the distinction of being located in the center of the South Atlantic Magnetic Anomaly. Geologically is emplaced in a Neoproterozoic basement, in a region with scarce anthropogenic interference. The OAGA has, since 2012, with a GSM-90FD dIdD v7.0 and GSM-90F Overhauser, both of GEM Systems. In addition has a super-SID receiver provided by the Stanford University SOLAR Center, as a complement for educational purposes. Likewise the installation of a seismograph REF TEK-151-120A and VLF antenna is being done since the beginning of 2013.

  10. Archives, Databases &the Emerging Virtual Observatories

    NASA Astrophysics Data System (ADS)

    Golombek, Daniel

    Historically, any newly discovered object needed to be "confirmed" with optical observations. Catalogues were published, such as the Parkes Radio Sources Catalogue (PKS), with stamp-sized photographs that allowed one to "see" what was just found. This is still somewhat true, although far less than in the past. The world is probably reaching an information overload with more efficient instruments, larger detectors, multiple wavelength coverage and an increasing number of ground- and space-based facilities. At the same time, information technology is catching up and allows humans the use of data regardless of where they reside. An increasing need for multi-wavelength observations to understand the underlying physics of the observed phenomena and the challenge to mine petabyte databases is leading to a federation of archives and to a cooperation among computer scientists and astronomers. These are the seeds of a virtual observatory, a cyberspace entity where the data is ready to be found and analyzed. In the United States of America, the National Science Foundation (NSF) and the National Aeronautics and Space Administration (NASA) are funding initiatives that will lead to the creation of this entity. This paper describes these projects.

  11. Archives, Databases and the Emerging Virtual Observatories

    NASA Astrophysics Data System (ADS)

    Golombek, D.

    Historically, any newly discovered object needed to be "confirmed" with optical observations. Catalogs were published, like the PKS, with stamp-sized photographs that allowed us to "see" what was just found. This is still somewhat true, although far less than in the past. We are probably reaching an information overload with more efficient instruments, larger detectors, multiple wavelength coverage and an increasing number of ground and space-based facilities. At the same time, information technology is catching up and is allowing us to be able to use the data regardless of where they reside. An increasing need of multi-wavelength observations to understand the underlying physics of the observed phenomena, coupled with availability of formal and informal data archives and the realization that petabyte databases present a particular challenge to mine is leading to a federation of archives to set standards, a cooperation among computer scientists and astronomers to create the infrastructure that will lead to a virtual observatory: a cyberspace location where the data is ready to be analyzed. In the US, the National Science Foundation (NSF) and the National Aeronautics and Space Administration (NASA) are funding initiatives that will lead to the creation of this entity. This presentation will describe these projects.

  12. Las Cumbres Observatory Global Telescope Network

    NASA Astrophysics Data System (ADS)

    Brown, T. M.; Baliber, N.; Bianco, F. B.; Bowman, M.; Burleson, B.; Conway, P.; Crellin, M.; Depagne, É.; De Vera, J.; Dilday, B.; Dragomir, D.; Dubberley, M.; Eastman, J. D.; Elphick, M.; Falarski, M.; Foale, S.; Ford, M.; Fulton, B. J.; Garza, J.; Gomez, E. L.; Graham, M.; Greene, R.; Haldeman, B.; Hawkins, E.; Haworth, B.; Haynes, R.; Hidas, M.; Hjelstrom, A. E.; Howell, D. A.; Hygelund, J.; Lister, T. A.; Lobdill, R.; Martinez, J.; Mullins, D. S.; Norbury, M.; Parrent, J.; Paulson, R.; Petry, D. L.; Pickles, A.; Posner, V.; Rosing, W. E.; Ross, R.; Sand, D. J.; Saunders, E. S.; Shobbrook, J.; Shporer, A.; Street, R. A.; Thomas, D.; Tsapras, Y.; Tufts, J. R.; Valenti, S.; Vander Horst, K.; Walker, Z.; White, G.; Willis, M.

    2013-09-01

    Las Cumbres Observatory Global Telescope (LCOGT) is a young organization dedicated to time-domain observations at optical and (potentially) near-IR wavelengths. To this end, LCOGT is constructing a worldwide network of telescopes, including the two 2 m Faulkes telescopes, as many as 17 × 1 m telescopes, and as many as 23 × 40 cm telescopes. These telescopes initially will be outfitted for imaging and (excepting the 40 cm telescopes) spectroscopy at wavelengths between the atmospheric UV cutoff and the roughly 1-μm limit of silicon detectors. Since the first of LCOGT's 1 m telescopes are now being deployed, we lay out here LCOGT's scientific goals and the requirements that these goals place on network architecture and performance, we summarize the network's present and projected level of development, and we describe our expected schedule for completing it. In the bulk of the paper, we describe in detail the technical approaches that we have adopted to attain desired performance. In particular, we discuss our choices for the number and location of network sites, for the number and sizes of telescopes, for the specifications of the first generation of instruments, for the software that will schedule and control the network's telescopes and reduce and archive its data, and for the structure of the scientific and educational programs for which the network will provide observations.

  13. Distributed Computing for the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Chudoba, J.

    2015-12-01

    Pierre Auger Observatory operates the largest system of detectors for ultra-high energy cosmic ray measurements. Comparison of theoretical models of interactions with recorded data requires thousands of computing cores for Monte Carlo simulations. Since 2007 distributed resources connected via EGI grid are successfully used. The first and the second versions of production system based on bash scripts and MySQL database were able to submit jobs to all reliable sites supporting Virtual Organization auger. For many years VO auger belongs to top ten of EGI users based on the total used computing time. Migration of the production system to DIRAC interware started in 2014. Pilot jobs improve efficiency of computing jobs and eliminate problems with small and less reliable sites used for the bulk production. The new system has also possibility to use available resources in clouds. Dirac File Catalog replaced LFC for new files, which are organized in datasets defined via metadata. CVMFS is used for software distribution since 2014. In the presentation we give a comparison of the old and the new production system and report the experience on migrating to the new system.

  14. Instrumentation at the Anglo-Australian Observatory

    NASA Astrophysics Data System (ADS)

    Barden, Samuel C.

    2004-09-01

    The Anglo-Australian Observatory (AAO) has an instrumentation group for engineering, design, and fabrication that integrates tightly with an energetic group of instrument scientists1 to develop complex astronomical instruments. This instrumentation group puts ideas for innovative technical solutions generated by the instrument scientist group into reality. One demonstration of past achievement is the highly ambitious and successful 2dF instrument that yielded invaluable scientific insight into the cosmological structure of the universe. The more recent successes of the instrumentation group include the OzPoz fiber positioner for the FLAMES facility on the VLT and the award-winning, imaging and multi-object IRIS-2 infrared spectrograph for the AAT. VPH gratings were first put into action in LDSS++ on the AAT and numerous VPH gratings are now in routine use on the 6dF spectrograph for the UKST. Under development are a completely new and unique fiber positioning scheme (Echidna) for use in the FMOS instrument for Subaru; a double-beamed, VPH-based, bench-mounted spectrograph for 2dF; new IR and optical detector controllers; a renovation of the telescope and instrument control systems for the AAT; and a feasibility study for an Echidna-style positioner for the Gemini telescopes. Several other design studies are underway for new instrument technologies using leading edge and innovative concepts in robotics and fibers. The synergy between our scientists and engineers establishes a sound basis for solving the instrumentation challenges facing us.

  15. Optical Detectors

    NASA Astrophysics Data System (ADS)

    Goushcha, Alexander; Tabbert, Bernd

    Optical detectors are applied in all fields of human activities - from basic research to commercial applications in communication, automotive, medical imaging, homeland security, and other fields. The processes of light interaction with matter described in other chapters of this handbook form the basis for understanding the optical detectors physics and device properties.

  16. Optical Detectors

    NASA Astrophysics Data System (ADS)

    Tabbert, Bernd; Goushcha, Alexander

    Optical detectors are applied in all fields of human activities from basic research to commercial applications in communication, automotive, medical imaging, homeland security, and other fields. The processes of light interaction with matter described in other chapters of this handbook form the basis for understanding the optical detectors physics and device properties.

  17. Ny-Alesund Geodetic Observatory

    NASA Technical Reports Server (NTRS)

    Sieber, Moritz

    2013-01-01

    In 2012 the 20-m telescope at Ny-Alesund, Svalbard, operated by the Norwegian Mapping Authority (NMA), took part in 163 out of 168 scheduled sessions of the IVS program. Since spring, all data was transferred by network, and the receiver monitoring computer was replaced by a bus-coupler. In autumn, the NMA received building permission for a new observatory from the Governor of Svalbard. The bidding process and first construction work for the infrastructure will start in 2013.

  18. High Dynamics and Precision Optical Measurement Using a Position Sensitive Detector (PSD) in Reflection-Mode: Application to 2D Object Tracking over a Smart Surface

    PubMed Central

    Ivan, Ioan Alexandru; Ardeleanu, Mihai; Laurent, Guillaume J.

    2012-01-01

    When related to a single and good contrast object or a laser spot, position sensing, or sensitive, detectors (PSDs) have a series of advantages over the classical camera sensors, including a good positioning accuracy for a fast response time and very simple signal conditioning circuits. To test the performance of this kind of sensor for microrobotics, we have made a comparative analysis between a precise but slow video camera and a custom-made fast PSD system applied to the tracking of a diffuse-reflectivity object transported by a pneumatic microconveyor called Smart-Surface. Until now, the fast system dynamics prevented the full control of the smart surface by visual servoing, unless using a very expensive high frame rate camera. We have built and tested a custom and low cost PSD-based embedded circuit, optically connected with a camera to a single objective by means of a beam splitter. A stroboscopic light source enhanced the resolution. The obtained results showed a good linearity and a fast (over 500 frames per second) response time which will enable future closed-loop control by using PSD. PMID:23223078

  19. High dynamics and precision optical measurement using a position sensitive detector (PSD) in reflection-mode: application to 2D object tracking over a Smart Surface.

    PubMed

    Ivan, Ioan Alexandru; Ardeleanu, Mihai; Laurent, Guillaume J

    2012-01-01

    When related to a single and good contrast object or a laser spot, position sensing, or sensitive, detectors (PSDs) have a series of advantages over the classical camera sensors, including a good positioning accuracy for a fast response time and very simple signal conditioning circuits. To test the performance of this kind of sensor for microrobotics, we have made a comparative analysis between a precise but slow video camera and a custom-made fast PSD system applied to the tracking of a diffuse-reflectivity object transported by a pneumatic microconveyor called Smart-Surface. Until now, the fast system dynamics prevented the full control of the smart surface by visual servoing, unless using a very expensive high frame rate camera. We have built and tested a custom and low cost PSD-based embedded circuit, optically connected with a camera to a single objective by means of a beam splitter. A stroboscopic light source enhanced the resolution. The obtained results showed a good linearity and a fast (over 500 frames per second) response time which will enable future closed-loop control by using PSD. PMID:23223078

  20. ALOHA Cabled Observatory: Early Results

    NASA Astrophysics Data System (ADS)

    Howe, B. M.; Lukas, R.; Duennebier, F. K.

    2011-12-01

    The ALOHA Cabled Observatory (ACO) was installed 6 June 2011, extending power, network communications and timing to a seafloor node and instruments at 4726 m water depth 100 km north of Oahu. The system was installed using ROV Jason operated from the R/V Kilo Moana. Station ALOHA is the field site of the Hawaii Ocean Time-series (HOT) program that has investigated temporal dynamics in biology, physics, and chemistry since 1988. HOT conducts near monthly ship-based sampling and makes continuous observations from moored instruments to document and study climate and ecosystem variability over semi-diurnal to decadal time scales. The cabled observatory system will provide the infrastructure for continuous, interactive ocean sampling enabling new measurements as well as a new mode of ocean observing that integrates ship and cabled observations. The ACO is a prototypical example of a deep observatory system that uses a retired first-generation fiber-optic telecommunications cable. Sensors provide live video, sound from local and distant sources, and measure currents, pressure, temperature, and salinity. Preliminary results will be presented and discussed.

  1. Vibration budget for observatory equipment

    NASA Astrophysics Data System (ADS)

    MacMartin, Douglas G.; Thompson, Hugh

    2015-07-01

    Vibration from equipment mounted on the telescope and in summit support buildings has been a source of performance degradation at existing astronomical observatories, particularly for adaptive optics performance. Rather than relying only on best practices to minimize vibration, we present here a vibration budget that specifies allowable force levels from each source of vibration in the observatory (e.g., pumps, chillers, cryocoolers, etc.). This design tool helps ensure that the total optical performance degradation due to vibration is less than the corresponding error budget allocation and is also useful in design trade-offs, specifying isolation requirements for equipment, and tightening or widening individual equipment vibration specifications as necessary. The vibration budget relies on model-based analysis of the optical consequences that result from forces applied at different locations and frequencies, including both image jitter and primary mirror segment motion. We develop this tool here for the Thirty Meter Telescope but hope that this approach will be broadly useful to other observatories, not only in the design phase, but for verification and operations as well.

  2. Collision avoidance during group evasive manoeuvres: a comparison of real versus simulated swarms with manipulated vision and surface wave detectors

    PubMed Central

    Romey, William L.; Miller, Magenta M.; Vidal, Jose M.

    2014-01-01

    Coordinated group motion has been studied extensively both in real systems (flocks, swarms and schools) and in simulations (self-propelled particle (SPP) models using attraction and repulsion rules). Rarely are attraction and repulsion rules manipulated, and the resulting emergent behaviours of real and simulation systems are compared. We compare swarms of sensory-deprived whirligig beetles with matching simulation models. Whirligigs live at the water's surface and coordinate their grouping using their eyes and antennae. We filmed groups of beetles in which antennae or eyes had been unilaterally obstructed and measured individual and group behaviours. We then developed and compared eight SPP simulation models. Eye-less beetles formed larger diameter resting groups than antenna-less or control groups. Antenna-less groups collided more often with each other during evasive group movements than did eye-less or control groups. Simulations of antenna-less individuals produced no difference from a control (or a slight decrease) in group diameter. Simulations of eye-less individuals produced an increase in group diameter. Our study is important in (i) differentiating between group attraction and repulsion rules, (ii) directly comparing emergent properties of real and simulated groups, and (iii) exploring a new sensory modality (surface wave detection) to coordinate group movement. PMID:24943378

  3. Collision avoidance during group evasive manoeuvres: a comparison of real versus simulated swarms with manipulated vision and surface wave detectors.

    PubMed

    Romey, William L; Miller, Magenta M; Vidal, Jose M

    2014-08-01

    Coordinated group motion has been studied extensively both in real systems (flocks, swarms and schools) and in simulations (self-propelled particle (SPP) models using attraction and repulsion rules). Rarely are attraction and repulsion rules manipulated, and the resulting emergent behaviours of real and simulation systems are compared. We compare swarms of sensory-deprived whirligig beetles with matching simulation models. Whirligigs live at the water's surface and coordinate their grouping using their eyes and antennae. We filmed groups of beetles in which antennae or eyes had been unilaterally obstructed and measured individual and group behaviours. We then developed and compared eight SPP simulation models. Eye-less beetles formed larger diameter resting groups than antenna-less or control groups. Antenna-less groups collided more often with each other during evasive group movements than did eye-less or control groups. Simulations of antenna-less individuals produced no difference from a control (or a slight decrease) in group diameter. Simulations of eye-less individuals produced an increase in group diameter. Our study is important in (i) differentiating between group attraction and repulsion rules, (ii) directly comparing emergent properties of real and simulated groups, and (iii) exploring a new sensory modality (surface wave detection) to coordinate group movement.

  4. SEVAN CRO Particle Detector for Solar Physics and Space Weather research

    NASA Astrophysics Data System (ADS)

    Roša, D.; Angelov, Ch.; Arakelyan, K.; Arsov, T.; Avakyan, K.; Chilingarian, A.; Chilingaryan, S.; Hovhanissyan, A.; Hovhannisyan, T.; Hovsepyan, G.; Sargsyan, D.; Hržina, D.; Kalapov, I.; Karapetyan, T.; Kozliner, L.; Mailyan, B.; Maričić, D.; Nishev, A.; Pokhsraryan, D.; Reymers, A.; Romštajn, I.; Stamenov, J.; Tchorbadjieff, A.; Vanyan, L.

    The installation of the SEVAN CRO particle detector at Zagreb Astronomical Observatory was finished at the end of 2008. The detector is a fully autonomous unit, with the capability to send data via the Internet, and it is a part of the SEVAN (Space Environmental Viewing and Analysis Network), which includes detectors located at middle to low latitudes. Till to now the SEVAN modules are installed at Aragats Space Environmental Centre in Armenia (3 units), Bulgaria (Moussala) and Croatia (Zagreb). SEVAN detectors are use for simultaneous measurements of flux of most species of secondary cosmic rays born in the atmospheric cascade caused by primary ions and solar neutrons. These devices can be used for exploration of solar modulation effects on galactic cosmic rays. The main scientific aim is to the improve research of solar particle acceleration in the vicinity of the Sun by detecting highest energy solar cosmic rays giving additional secondaries detected by surface particle detectors and to improve researches of the space environment conditions.

  5. Mass composition studies of Ultra High Energy cosmic rays through the measurement of the Muon Production Depths at the Pierre Auger Observatory

    SciTech Connect

    Collica, Laura

    2014-01-01

    The Pierre Auger Observatory (Auger) in Argentina studies Ultra High Energy Cosmic Rays (UHECRs) physics. The flux of cosmic rays at these energies (above 1018 eV) is very low (less than 100 particle/km2-year) and UHECR properties must be inferred from the measurements of the secondary particles that the cosmic ray primary produces in the atmosphere. These particles cascades are called Extensive Air Showers (EAS) and can be studied at ground by deploying detectors covering large areas. The EAS physics is complex, and the properties of secondary particles depend strongly on the first interaction, which takes place at an energy beyond the ones reached at accelerators. As a consequence, the analysis of UHECRs is subject to large uncertainties and hence many of their properties, in particular their composition, are still unclear. Two complementary techniques are used at Auger to detect EAS initiated by UHE- CRs: a 3000 km2 surface detector (SD) array of water Cherenkov tanks which samples particles at ground level and fluorescence detectors (FD) which collect the ultraviolet light emitted by the de-excitation of nitrogen nuclei in the atmosphere, and can operate only in clear, moonless nights. Auger is the largest cosmic rays detector ever built and it provides high-quality data together with unprecedented statistics. The main goal of this thesis is the measurement of UHECR mass composition using data from the SD of the Pierre Auger Observatory. Measuring the cosmic ray composition at the highest energies is of fundamental importance from the astrophysical point of view, since it could discriminate between different scenarios of origin and propagation of cosmic rays. Moreover, mass composition studies are of utmost importance for particle physics. As a matter of fact, knowing the composition helps in exploring the hadronic interactions at ultra-high energies, inaccessible to present accelerator experiments.

  6. The Allegheny Observatory search for planetary systems

    NASA Technical Reports Server (NTRS)

    Gatewood, George D.

    1989-01-01

    The accomplishments of the observatory's search for planetary systems are summarized. Among these were the construction, implementation, and regular use of the Multichannel Astrometric Photometer (MAP), and the design, fabrication and use of the second largest refractor objective built since 1950. The MAP parallax and planetary observing programs are described. Various developments concerning alternate solid state photodetectors and telescope instrumentation are summarized. The extreme accuracy of the system is described in relation to a study of the position and velocity of the members of the open cluster Upgren 1. The binary star system stringently tests the theory of stellar evolution since it is composed of an evolved giant F5 III and a subgiant F5 IV star. A study that attempts to measure the luminosities, surface temperatures, and masses of these stars is discussed.

  7. Gaseous Detectors

    NASA Astrophysics Data System (ADS)

    Titov, Maxim

    Since long time, the compelling scientific goals of future high-energy physics experiments were a driving factor in the development of advanced detector technologies. A true innovation in detector instrumentation concepts came in 1968, with the development of a fully parallel readout for a large array of sensing elements - the Multi-Wire Proportional Chamber (MWPC), which earned Georges Charpak a Nobel prize in physics in 1992. Since that time radiation detection and imaging with fast gaseous detectors, capable of economically covering large detection volumes with low mass budget, have been playing an important role in many fields of physics. Advances in photolithography and microprocessing techniques in the chip industry during the past decade triggered a major transition in the field of gas detectors from wire structures to Micro-Pattern Gas Detector (MPGD) concepts, revolutionizing cell-size limitations for many gas detector applications. The high radiation resistance and excellent spatial and time resolution make them an invaluable tool to confront future detector challenges at the next generation of colliders. The design of the new micro-pattern devices appears suitable for industrial production. Novel structures where MPGDs are directly coupled to the CMOS pixel readout represent an exciting field allowing timing and charge measurements as well as precise spatial information in 3D. Originally developed for the high-energy physics, MPGD applications have expanded to nuclear physics, photon detection, astroparticle and neutrino physics, neutron detection, and medical imaging.

  8. Observatory enabled modeling of the Global Carbon Cycle

    NASA Astrophysics Data System (ADS)

    Schimel, D.; Fox, A. M.; Moore, D. J.; Sacks, W. J.; Berukoff, S. J.

    2011-12-01

    A central challenge to global modeling of the terrestrial carbon cycle is the scaling of organism-scale characteristics to large regions. Emerging ground- and space-based global observatories will allow coupling observations directly to state and parameter values in a state-of-the-art coupled carbon climate model. Model-data fusion will qualitatively improve understanding and forecasting of interannual to centennial scale responses of terrestrial ecosystems and carbon cycle to global environmental change. This modeling study will use the baseline measures of global terrestrial ecosystem biochemical composition to reduce uncertainty in forecasting E&CC responses to climate and land-use change. The NCAR Community Land Model (Community Land Model - Carbon/Nitrogen or CLM-CN) simulates carbon, water and energy exchange at the land surface and includes detailed parameters governing plant-mediated fluxes and storage NEON and NCAR are developing a data assimilation version of the CLM, designed to work with new observatory data. Data requirements of CLM are quite different from earlier generation land surface models because the nitrogen cycle is explicitly simulated. Nitrogen concentrations regulate plant photosynthesis and decomposition of dead organic matter but their within biome and global distributions are poorly constrained by observations. Developing a Observatory-enabled version of the CLM, and the cyberinfrastructure to support it creates a very different set of requirements for modeling and observatory information systems than traditional approaches. In the talk, we will discuss briefly the science of carbon data assimilation and the observing requirements it generates.

  9. Proceedings of the Third Infrared Detector Technology Workshop

    NASA Technical Reports Server (NTRS)

    Mccreight, Craig R. (Compiler)

    1989-01-01

    This volume consists of 37 papers which summarize results presented at the Third Infrared Detector Technology Workshop, held February 7-9, 1989, at Ames Research Center. The workshop focused on infrared (IR) detector, detector array, and cryogenic electronic technologies relevant to low-background space astronomy. Papers on discrete IR detectors, cryogenic readouts, extrinsic and intrinsic IR arrays, and recent results from ground-based observations with integrated arrays were given. Recent developments in the second-generation Hubble Space Telescope (HST) infrared spectrometer and in detectors and arrays for the European Space Agency's Infrared Space Observatory (ISO) are also included, as are status reports on the Space Infrared Telescope Facility (SIRTF) and the Stratospheric Observatory for Infrared Astronomy (SOFIA) projects.

  10. Alkali metal ionization detector

    DOEpatents

    Bauerle, James E.; Reed, William H.; Berkey, Edgar

    1978-01-01

    Variations in the conventional filament and collector electrodes of an alkali metal ionization detector, including the substitution of helical electrode configurations for either the conventional wire filament or flat plate collector; or, the substitution of a plurality of discrete filament electrodes providing an in situ capability for transferring from an operationally defective filament electrode to a previously unused filament electrode without removing the alkali metal ionization detector from the monitored environment. In particular, the helical collector arrangement which is coaxially disposed about the filament electrode, i.e. the thermal ionizer, provides an improved collection of positive ions developed by the filament electrode. The helical filament design, on the other hand, provides the advantage of an increased surface area for ionization of alkali metal-bearing species in a monitored gas environment as well as providing a relatively strong electric field for collecting the ions at the collector electrode about which the helical filament electrode is coaxially positioned. Alternatively, both the filament and collector electrodes can be helical. Furthermore, the operation of the conventional alkali metal ionization detector as a leak detector can be simplified as to cost and complexity, by operating the detector at a reduced collector potential while maintaining the sensitivity of the alkali metal ionization detector adequate for the relatively low concentration of alkali vapor and aerosol typically encountered in leak detection applications.

  11. Life Finder Detectors; Detector Needs and Status for Spectroscopic Biosignature Characterization

    NASA Astrophysics Data System (ADS)

    Rauscher, Bernard J.; Bolcar, Matthew R.; Clampin, Mark; Domagal-Goldman, Shawn; McElwain, Michael W.; Moseley, Samuel H.; Stahle, Carl; Stark, Christopher C.; Thronson, Harley A.

    2016-01-01

    The search for life on other worlds looms large in NASA's future. Outside our solar system, direct spectroscopic biosignature characterization using very large UV-Optical-IR telescopes with coronagraphs or starshades is a core technique to both AURA's High Definition Space Telescope (HDST) concept and NASA's 30-year strategic plan. These giant space observatories require technological advancements in several areas, one of which is detectors. In this presentation, we review the detector requirements for spectroscopic biosignature characterization and discuss the status of some existing and proposed detector technologies for meeting them.

  12. Detectors in Extreme Conditions

    SciTech Connect

    Blaj, G.; Carini, G.; Carron, S.; Haller, G.; Hart, P.; Hasi, J.; Herrmann, S.; Kenney, C.; Segal, J.; Tomada, A.

    2015-08-06

    Free Electron Lasers opened a new window on imaging the motion of atoms and molecules. At SLAC, FEL experiments are performed at LCLS using 120Hz pulses with 1012 - 1013 photons in 10 femtoseconds (billions of times brighter than the most powerful synchrotrons). This extreme detection environment raises unique challenges, from obvious to surprising. Radiation damage is a constant threat due to accidental exposure to insufficiently attenuated beam, focused beam and formation of ice crystals reflecting the beam onto the detector. Often high power optical lasers are also used (e.g., 25TW), increasing the risk of damage or impeding data acquisition through electromagnetic pulses (EMP). The sample can contaminate the detector surface or even produce shrapnel damage. Some experiments require ultra high vacuum (UHV) with strict design, surface contamination and cooling requirements - also for detectors. The setup is often changed between or during experiments with short turnaround times, risking mechanical and ESD damage, requiring work planning, training of operators and sometimes continuous participation of the LCLS Detector Group in the experiments. The detectors used most often at LCLS are CSPAD cameras for hard x-rays and pnCCDs for soft x-rays.

  13. Observatory Sponsoring Astronomical Image Contest

    NASA Astrophysics Data System (ADS)

    2005-05-01

    Forget the headphones you saw in the Warner Brothers thriller Contact, as well as the guttural throbs emanating from loudspeakers at the Very Large Array in that 1997 movie. In real life, radio telescopes aren't used for "listening" to anything - just like visible-light telescopes, they are used primarily to make images of astronomical objects. Now, the National Radio Astronomy Observatory (NRAO) wants to encourage astronomers to use radio-telescope data to make truly compelling images, and is offering cash prizes to winners of a new image contest. Radio Galaxy Fornax A Radio Galaxy Fornax A Radio-optical composite image of giant elliptical galaxy NGC 1316, showing the galaxy (center), a smaller companion galaxy being cannibalized by NGC 1316, and the resulting "lobes" (orange) of radio emission caused by jets of particles spewed from the core of the giant galaxy Click on image for more detail and images CREDIT: Fomalont et al., NRAO/AUI/NSF "Astronomy is a very visual science, and our radio telescopes are capable of producing excellent images. We're sponsoring this contest to encourage astronomers to make the extra effort to turn good images into truly spectacular ones," said NRAO Director Fred K.Y. Lo. The contest, offering a grand prize of $1,000, was announced at the American Astronomical Society's meeting in Minneapolis, Minnesota. The image contest is part of a broader NRAO effort to make radio astronomical data and images easily accessible and widely available to scientists, students, teachers, the general public, news media and science-education professionals. That effort includes an expanded image gallery on the observatory's Web site. "We're not only adding new radio-astronomy images to our online gallery, but we're also improving the organization and accessibility of the images," said Mark Adams, head of education and public outreach (EPO) at NRAO. "Our long-term goal is to make the NRAO Image Gallery an international resource for radio astronomy imagery

  14. MS Detectors

    SciTech Connect

    Koppenaal, David W.; Barinaga, Charles J.; Denton, M Bonner B.; Sperline, Roger P.; Hieftje, Gary M.; Schilling, G. D.; Andrade, Francisco J.; Barnes IV., James H.

    2005-11-01

    Good eyesight is often taken for granted, a situation that everyone appreciates once vision begins to fade with age. New eyeglasses or contact lenses are traditional ways to improve vision, but recent new technology, i.e. LASIK laser eye surgery, provides a new and exciting means for marked vision restoration and improvement. In mass spectrometry, detectors are the 'eyes' of the MS instrument. These 'eyes' have also been taken for granted. New detectors and new technologies are likewise needed to correct, improve, and extend ion detection and hence, our 'chemical vision'. The purpose of this report is to review and assess current MS detector technology and to provide a glimpse towards future detector technologies. It is hoped that the report will also serve to motivate interest, prompt ideas, and inspire new visions for ion detection research.

  15. SNO Data: Results from Experiments at the Sudbury Neutrino Observatory

    DOE Data Explorer

    The Sudbury Neutrino Observatory (SNO) was built 6800 feet under ground, in INCO's Creighton mine near Sudbury, Ontario. SNO is a heavy-water Cherenkov detector that is designed to detect neutrinos produced by fusion reactions in the sun. It uses 1000 tonnes of heavy water, on loan from Atomic Energy of Canada Limited (AECL), contained in a 12 meter diameter acrylic vessel. Neutrinos react with the heavy water (D2O) to produce flashes of light called Cherenkov radiation. This light is then detected by an array of 9600 photomultiplier tubes mounted on a geodesic support structure surrounding the heavy water vessel. The detector is immersed in light (normal) water within a 30 meter barrel-shaped cavity (the size of a 10 story building!) excavated from Norite rock. Located in the deepest part of the mine, the overburden of rock shields the detector from cosmic rays. The detector laboratory is extremely clean to reduce background signals from radioactive elements present in the mine dust which would otherwise hide the very weak signal from neutrinos. (From http://www.sno.phy.queensu.ca/]

    The SNO website provides access to various datasets. See also the SNO Image Catalog at http://www.sno.phy.queensu.ca/sno/images/ and computer-generated images of SNO events at http://www.sno.phy.queensu.ca/sno/events/ and the list of published papers.

  16. The Arecibo Observatory Space Academy

    NASA Astrophysics Data System (ADS)

    Rodriguez-Ford, Linda A.; Zambrano-Marin, Luisa; Petty, Bryan M.; Sternke, Elizabeth; Ortiz, Andrew M.; Rivera-Valentin, Edgard G.

    2015-11-01

    The Arecibo Observatory Space Academy (AOSA) is a ten (10) week pre-college research program for students in grades 9-12. Our mission is to prepare students for academic and professional careers by allowing them to receive an independent and collaborative research experience on topics related to space and aide in their individual academic and social development. Our objectives are to (1) Supplement the student’s STEM education via inquiry-based learning and indirect teaching methods, (2) Immerse students in an ESL environment, further developing their verbal and written presentation skills, and (3) To foster in every student an interest in science by exploiting their natural curiosity and knowledge in order to further develop their critical thinking and investigation skills. AOSA provides students with the opportunity to share lectures with Arecibo Observatory staff, who have expertise in various STEM fields. Each Fall and Spring semester, selected high school students, or Cadets, from all over Puerto Rico participate in this Saturday academy where they receive experience designing, proposing, and carrying out research projects related to space exploration, focusing on four fields: Physics/Astronomy, Biology, Engineering, and Sociology. Cadets get the opportunity to explore their topic of choice while practicing many of the foundations of scientific research with the goal of designing a space settlement, which they present at the NSS-NASA Ames Space Settlement Design Contest. At the end of each semester students present their research to their peers, program mentors, and Arecibo Observatory staff. Funding for this program is provided by NASA SSERVI-LPI: Center for Lunar Science and Exploration with partial support from the Angel Ramos Visitor Center through UMET and management by USRA.

  17. The CEOS Recovery Observatory Pilot

    NASA Astrophysics Data System (ADS)

    Hosford, S.; Proy, C.; Giros, A.; Eddy, A.; Petiteville, I.; Ishida, C.; Gaetani, F.; Frye, S.; Zoffoli, S.; Danzeglocke, J.

    2015-04-01

    Over the course of the last decade, large populations living in vulnerable areas have led to record damages and substantial loss of life in mega-disasters ranging from the deadly Indian Ocean tsunami of 2004 and Haiti earthquake of 2010; the catastrophic flood damages of Hurricane Katrina in 2005 and the Tohoku tsunami of 2011, and the astonishing extent of the environmental impact of the Deepwater Horizon explosion in 2009. These major catastrophes have widespread and long-lasting impacts with subsequent recovery and reconstruction costing billions of euros and lasting years. While satellite imagery is used on an ad hoc basis after many disasters to support damage assessment, there is currently no standard practice or system to coordinate acquisition of data and facilitate access for early recovery planning and recovery tracking and monitoring. CEOS led the creation of a Recovery Observatory Oversight Team, which brings together major recovery stakeholders such as the UNDP and the World Bank/Global Facility for Disaster Reduction and Recovery, value-adding providers and leading space agencies. The principal aims of the Observatory are to: 1. Demonstrate the utility of a wide range of earth observation data to facilitate the recovery and reconstruction phase following a major catastrophic event; 2. Provide a concrete case to focus efforts in identifying and resolving technical and organizational obstacles to facilitating the visibility and access to a relevant set of EO data; and 3. Develop dialogue and establish institutional relationships with the Recovery phase user community to best target data and information requirements; The paper presented here will describe the work conducted in preparing for the triggering of a Recovery Observatory including support to rapid assessments and Post Disaster Needs Assessments by the EO community.

  18. The Orbiting Carbon Observatory (OCO)

    NASA Technical Reports Server (NTRS)

    Miller, Charles E.

    2005-01-01

    CO2 is the principal human generated driver of climate change. Accurate forecasting of future climate requires an improved understanding of the global carbon cycle and its interaction with the climate system. The Orbiting Carbon Observatory (OCO) will make global, space-based observations of atmospheric CO2 with the precision, resolution, and coverage needed to understand sources and sinks. OCO data will provide critical information for decision makers including the scientific basis for policy formulation, guide for carbon management strategies and treaty monitoring.

  19. Stratospheric Observatory for Infrared Astronomy

    NASA Technical Reports Server (NTRS)

    Becklin, Eric E.

    2001-01-01

    The joint U.S. and German SOFIA project to develop and operate a 2.5-meter infrared airborne telescope in a Boeing 747-SP is now well into development. First science flights will begin in 2004 with 20% of the observing time assigned to German investigators. The observatory is expected to operate for over 20 years. The sensitivity, characteristics and science instrument complement are discussed. Present and future instrumentation will allow unique astrobiology experiments to be carried out. Several experiments related to organic molecules in space will be discussed.

  20. Moderate temperature detector development

    NASA Technical Reports Server (NTRS)

    Marciniec, J. W.; Briggs, R. J.; Sood, A. K.

    1981-01-01

    P-side backside reflecting constant, photodiode characterization, and photodiode diffusion and G-R currents were investigated in an effort to develop an 8 m to 12 m infrared quantum detector using mercury cadmium telluride. Anodization, phosphorus implantation, and the graded band gap concept were approaches considered for backside formation. Variable thickness diodes were fabricated with a back surface anodic oxide to investigate the effect of this surface preparation on the diffusion limited zero bias impedance. A modeling technique was refined to thoroughly model diode characteristics. Values for the surface recombination velocity in the depletion region were obtained. These values were improved by implementing better surface damage removal techniques.

  1. Ionizing Radiation Detector

    DOEpatents

    Wright, Gomez W.; James, Ralph B.; Burger, Arnold; Chinn, Douglas A.

    2003-11-18

    A CdZnTe (CZT) crystal provided with a native CdO dielectric coating to reduce surface leakage currents and thereby, improve the resolution of instruments incorporating detectors using CZT crystals is disclosed. A two step process is provided for forming the dielectric coating which includes etching the surface of a CZT crystal with a solution of the conventional bromine/methanol etch treatment, and passivating the CZT crystal surface with a solution of 10 w/o NH.sub.4 F and 10 w/o H.sub.2 O.sub.2 in water after attaching electrical contacts to the crystal surface.

  2. Concept and Layout of the EAS muon arrival time distribution measurements on Mt. Aragats Observatory

    NASA Astrophysics Data System (ADS)

    Mathes, Hermann Josef

    1999-08-01

    The lateral and longitudinal profiles of the EAS development show specific features depending on the primary mass due to various particle interaction parameters influencing the development of the particle cascade in the atmosphere. The large muon detector of the ANI Cosmic Ray Observatory on Mt. Aragats gives a good opportunity to measure muon arrival times. In view of a possible extension of the muon underground installation EAS simulations have been performed. They consider various detector configurations with respect to the EAS core position. The observed muon time dispersion show specific trends with increasing radial distance and primary mass. Particularly, simulations based on the GEANT package had been done to study the faked detector signals due to secondaries generated in the surrounding material. A design for upgrading the muon detector array is presented which implies additional fast timing photomultipliers attached to the existing scintillation detectors.

  3. Detector Mount Design for IGRINS

    NASA Astrophysics Data System (ADS)

    Oh, Jae Sok; Park, Chan; Cha, Sang-Mok; Yuk, In-Soo; Park, Kwijong; Kim, Kang-Min; Chun, Moo-Young; Ko, Kyeongyeon; Oh, Heeyoung; Jeong, Ueejeong; Nah, Jakyoung; Lee, Hanshin; Jaffe, Daniel T.

    2014-06-01

    The Immersion Grating Infrared Spectrometer (IGRINS) is a near-infrared wide-band high-resolution spectrograph jointly developed by the Korea Astronomy and Space Science Institute and the University of Texas at Austin. IGRINS employs three HAWAII-2RG Focal Plane Array (H2RG FPA) detectors. We present the design and fabrication of the detector mount for the H2RG detector. The detector mount consists of a detector housing, an ASIC housing, a Field Flattener Lens (FFL) mount, and a support base frame. The detector and the ASIC housing should be kept at 65 K and the support base frame at 130 K. Therefore they are thermally isolated by the support made of GFRP material. The detector mount is designed so that it has features of fine adjusting the position of the detector surface in the optical axis and of fine adjusting yaw and pitch angles in order to utilize as an optical system alignment compensator. We optimized the structural stability and thermal characteristics of the mount design using computer-aided 3D modeling and finite element analysis. Based on the structural and thermal analysis, the designed detector mount meets an optical stability tolerance and system thermal requirements. Actual detector mount fabricated based on the design has been installed into the IGRINS cryostat and successfully passed a vacuum test and a cold test.

  4. Developing the planetary science virtual observatory

    NASA Astrophysics Data System (ADS)

    Erard, Stéphane; Capria, Maria Teresa; Chanteur, Gerard; Le Sidaner, Pierre; Henry, Florence; Cecconi, Baptiste; Andre, Nicolas; Schmitt, Bernard; Genot, Vincent; Chauvin, Cyril

    In the framework of the Europlanet-RI program, a prototype Virtual Observatory dedicated to Planetary Science has been set up. Most of the activity was dedicated to the definition of standards to handle data in this field. The aim was to facilitate searches in big archives as well as sparse databases, to make on-line data access and visualization possible, and to allow small data providers to make their data available in an interoperable environment with minimum effort. This system makes intensive use of studies and developments led in Astronomy (IVOA, International Virtual Observatory Alliance), Solar and Heliospheric Sciences (HELIO, Heliophysics Integrated Observatory), Space Physics (SPASE, Space Physics Archive Search and Extract) and Planetary Data Space Archive services (IPDA, International Planetary Data Alliance). In particular, it remains consistent with extensions of IVOA standards. The current architecture is aiming at connecting existing data services with IVOA protocols (Cone Search, TAP (Table Access Protocol)…) or with the IPDA protocol (PDAP, Planetary Data Access Protocol) whenever relevant. However, a more general standard has been devised to handle the specific complexity of Planetary Science, e.g. in terms of measurement types and coordinate frames. This protocol, named EPN-TAP (Europlanet-TAP), is based on TAP and includes precise requirements to describe the contents of a data service. It is based on an IVOA compliant data model (EPNcore). A light framework (DaCHS/GAVO) and a procedure have been identified to install small data services, and several hands-on sessions have been organized already. The data services are declared in standard IVOA registries. Support to new data services in Europe will be provided in the framework of the proposed H2020 Europlanet program, with a focus on planetary mission support (Rosetta, Cassini…). Although TAP services can be accessed and queried from tools such as TOPCAT, a full client has been developed

  5. Protection of the Guillermo Haro Astrophysical Observatory

    NASA Astrophysics Data System (ADS)

    Carrasco, E.; Carraminana, A. P.

    The Guillermo Haro Astrophysical Observatory, with a 2m telescope, is one of only two professional observatories in Mexico. The observatory, run by the InstitutoNacional de Astrofisica, Optica y Electronica (INAOE), is located in the north of Mexico, in Cananea, Sonora. Since 1995 the observatory has faced the potential threat of pollution by an open cast mine to be opened at 3kms from the observatory. In the absence of national or regional laws enforcing protection to astronomical sites in Mexico, considerable effort has been needed to guarantee the conditions of the site. We present the studies carried out to ensure the protection of the Guillermo Haro Observatory from pollution due to dust, light and vibrations.

  6. Edgeless silicon pad detectors

    NASA Astrophysics Data System (ADS)

    Perea Solano, B.; Abreu, M. C.; Avati, V.; Boccali, T.; Boccone, V.; Bozzo, M.; Capra, R.; Casagrande, L.; Chen, W.; Eggert, K.; Heijne, E.; Klauke, S.; Li, Z.; Mäki, T.; Mirabito, L.; Morelli, A.; Niinikoski, T. O.; Oljemark, F.; Palmieri, V. G.; Rato Mendes, P.; Rodrigues, S.; Siegrist, P.; Silvestris, L.; Sousa, P.; Tapprogge, S.; Trocmé, B.

    2006-05-01

    We report measurements in a high-energy pion beam of the sensitivity of the edge region in "edgeless" planar silicon pad diode detectors diced through their contact implants. A large surface current on such an edge prevents the normal reverse biasing of the device, but the current can be sufficiently reduced by the use of a suitable cutting method, followed by edge treatment, and by operating the detector at low temperature. The depth of the dead layer at the diced edge is measured to be (12.5±8 stat..±6 syst.) μm.

  7. NOAA Atmospheric Baseline Observatories in the Arctic: Alaska & Greenland

    NASA Astrophysics Data System (ADS)

    Vasel, B. A.; Butler, J. H.; Schnell, R. C.; Crain, R.; Haggerty, P.; Greenland, S.

    2013-12-01

    The National Oceanic and Atmospheric Administration (NOAA) operates two year-round, long-term climate research facilities, known as Atmospheric Baseline Observatories (ABOs), in the Arctic Region. The Arctic ABOs are part of a core network to support the NOAA Global Monitoring Division's mission to acquire, evaluate, and make available accurate, long-term records of atmospheric gases, aerosol particles, and solar radiation in a manner that allows the causes of change to be understood. The observatory at Barrow, Alaska (BRW) was established in 1973 and is now host to over 200 daily measurements. Located a few kilometers to the east of the village of Barrow at 71.3° N it is also the northernmost point in the United States. Measurement records from Barrow are critical to our understanding of the Polar Regions including exchange among tundra, atmosphere, and ocean. Multiple data sets are available for carbon cycle gases, halogenated gases, solar radiation, aerosol properties, ozone, meteorology, and numerous others. The surface, in situ carbon dioxide record alone consists of over 339,000 measurements since the system was installed in July 1973. The observatory at Summit, Greenland (SUM) has been a partnership with the National Science Foundation (NSF) Division of Polar Programs since 2004, similar to that for South Pole. Observatory data records began in 1997 from this facility located at the top of the Greenland ice sheet at 72.58° N. Summit is unique as the only high-altitude (3200m), mid-troposphere, inland, Arctic observatory, largely free from outside local influences such as thawing tundra or warming surface waters. The measurement records from Summit help us understand long-range transport across the Arctic region, as well as interactions between air and snow. Near-real-time data are available for carbon cycle gases, halogenated gases, solar radiation, aerosol properties, meteorology, ozone, and numerous others. This poster will highlight the two facilities

  8. The Compton Gamma Ray Observatory

    NASA Astrophysics Data System (ADS)

    Gehrels, N.; Chipman, E.; Kniffen, D.

    1994-06-01

    The Arthur Holly Compton Gamma Ray Observatory Compton) is the second in NASA's series of great Observatories. Launched on 1991 April 5, Compton represents a dramatic increase in capability over previous gamma-ray missions. The spacecraft and scientific instruments are all in good health, and many significant discoveries have already been made. We describe the capabilities of the four scientific instruments, and the observing program of the first 2 years of the mission. Examples of early discoveries by Compton are enumerated, including the discovery that gamma-ray bursts are isotropic but spatially inhomogeneous in their distribution; the discovery of a new class of high-energy extragalacatic gamma-ray sources, the gamma-ray AGNs; the discovery of emission from SN 1987A in the nuclear line of Co-57; and the mapping of emission from Al-26 in the interstellar medium (ISM) near the Galactic center. Future observations will include deep surveys of selected regions of the sky, long-tem studies of individual objects, correlative studies of objects at gamma-ray and other energies, a Galactic plane survey at intermediate gamma-ray energies, and improved statistics on gamma-ray bursts to search for small anisotropies. After completion of the all-sky survey, a Guest Investigator program is in progress with guest observers' time share increasing from 30% upward for the late mission phases.

  9. A National Solar Digital Observatory

    NASA Astrophysics Data System (ADS)

    Hill, F.

    2000-05-01

    The continuing development of the Internet as a research tool, combined with an improving funding climate, has sparked new interest in the development of Internet-linked astronomical data bases and analysis tools. Here I outline a concept for a National Solar Digital Observatory (NSDO), a set of data archives and analysis tools distributed in physical location at sites which already host such systems. A central web site would be implemented from which a user could search all of the component archives, select and download data, and perform analyses. Example components include NSO's Digital Library containing its synoptic and GONG data, and the forthcoming SOLIS archive. Several other archives, in various stages of development, also exist. Potential analysis tools include content-based searches, visualized programming tools, and graphics routines. The existence of an NSDO would greatly facilitate solar physics research, as a user would no longer need to have detailed knowledge of all solar archive sites. It would also improve public outreach efforts. The National Solar Observatory is operated by AURA, Inc. under a cooperative agreement with the National Science Foundation.

  10. Photon detectors

    SciTech Connect

    Va`vra, J.

    1995-10-01

    J. Seguinot and T. Ypsilantis have recently described the theory and history of Ring Imaging Cherenkov (RICH) detectors. In this paper, I will expand on these excellent review papers, by covering the various photon detector designs in greater detail, and by including discussion of mistakes made, and detector problems encountered, along the way. Photon detectors are among the most difficult devices used in physics experiments, because they must achieve high efficiency for photon transport and for the detection of single photo-electrons. For gaseous devices, this requires the correct choice of gas gain in order to prevent breakdown and wire aging, together with the use of low noise electronics having the maximum possible amplification. In addition, the detector must be constructed of materials which resist corrosion due to photosensitive materials such as, the detector enclosure must be tightly sealed in order to prevent oxygen leaks, etc. The most critical step is the selection of the photocathode material. Typically, a choice must be made between a solid (CsI) or gaseous photocathode (TMAE, TEA). A conservative approach favors a gaseous photocathode, since it is continuously being replaced by flushing, and permits the photon detectors to be easily serviced (the air sensitive photocathode can be removed at any time). In addition, it can be argued that we now know how to handle TMAE, which, as is generally accepted, is the best photocathode material available as far as quantum efficiency is concerned. However, it is a very fragile molecule, and therefore its use may result in relatively fast wire aging. A possible alternative is TEA, which, in the early days, was rejected because it requires expensive CaF{sub 2} windows, which could be contaminated easily in the region of 8.3 eV and thus lose their UV transmission.

  11. Modeling contamination migration on the Chandra X-Ray Observatory

    NASA Technical Reports Server (NTRS)

    O'Dell, Stephen L.; Swartz, Douglas A.; Anderson, Scot K.; Chen, Kenny C.; Giordano, Rino J.; Knollenberg, Perry J.; Morris, Peter A.; Plucinsky, Paul P.; Tice, Neil W.; Tran, Hien

    2005-01-01

    During its first 5 years of operation, the cold (-60 C) optical blocking filter of the Advanced CCD Imaging Spectrometer (ACIS), on board the Chandra X-ray Observatory, has accumulated a contaminating layer that attenuates the low-energy x rays. To assist in assessing the likelihood of successfully baking off the contaminant, members of the Chandra Team developed contamination-migration simulation software. The simulation follows deposition onto and (temperature-dependent) vaporization from surfaces comprising a geometrical model of the Observatory. A separate thermal analysis, augmented by on-board temperature monitoring, provides temperatures for each surface of the same geometrical model. This paper describes the physical basis for the simulations, the methodologies, and the predicted migration of the contaminant for various bake-out scenarios and assumptions.

  12. NASA capabilities roadmap: advanced telescopes and observatories

    NASA Technical Reports Server (NTRS)

    Feinberg, Lee D.

    2005-01-01

    The NASA Advanced Telescopes and Observatories (ATO) Capability Roadmap addresses technologies necessary for NASA to enable future space telescopes and observatories collecting all electromagnetic bands, ranging from x-rays to millimeter waves, and including gravity-waves. It has derived capability priorities from current and developing Space Missions Directorate (SMD) strategic roadmaps and, where appropriate, has ensured their consistency with other NASA Strategic and Capability Roadmaps. Technology topics include optics; wavefront sensing and control and interferometry; distributed and advanced spacecraft systems; cryogenic and thermal control systems; large precision structure for observatories; and the infrastructure essential to future space telescopes and observatories.

  13. SOFIA Observatory Obtains 'First Light' Images

    NASA Video Gallery

    NASA's Stratospheric Observatory for Infrared Astronomy, or SOFIA, successfully obtained its "First Light"" images during an overnight flight May 26. Scientists are now processing the data gathered...

  14. The Uncertain Future of Arecibo Observatory

    NASA Astrophysics Data System (ADS)

    Altschuler, D. R.

    2009-05-01

    After forty years of existence, Arecibo Observatory has an uncertain future. On November 3th, 2006 the ``Senior Review'' (SR), an advisory panel, recommended to the astronomy division of NSF that the anual budget destinated to astronomy in the Observatory, should be reduced from US10.5 million annual to US8 million during the first 3 years. The SR also indicated that the Observatory have to be closed in 2011, if an external financial source is not found. The SR panel was called to find near US30 million in savings (approximately 25% of total budget of the five national observatories, including Arecibo) to redirect them to operate new future projects.

  15. A new Magnetic Observatory in Pantanal - Brazil

    NASA Astrophysics Data System (ADS)

    Siqueira, F.; Pinheiro, K.; Linthe, H.

    2013-05-01

    The aim of a Magnetic Observatory is to register the variations of the Earth's magnetic field in a long temporal scale. Using this data it is possible to study field variations of both external and internal origins. The external variations concern interactions between the magnetosphere and the solar wind, in general are measured in a short time scale. The internal field generated by convection of a high electrical conductivity fluid in the external core by a mechanism known as the geodynamo. Usually the internal field time variations are longer than in the external field and are called secular variations. Measurements carried out over the last century suggest that field intensity is decreasing rapidly. The decreasing of the field's intensity is not the same around the globe, especially at the SAMA (South Atlantic Magnetic Anomaly) regions, where this reduction is occurring faster. The global distribution of magnetic observatories is uneven, with few observatories in South America. In Brazil, there are three magnetic observatories, but only Vassouras Observatory (VSS- RJ) is part of the INTERMAGNET network. The National Observatory has plans to install seven new observatories in Brazil. Pantanal was the chosen location for installing the first observatory because of its privileged location, close to the SAMA region, and its data can contribute to more information about its origin. We followed the procedures suggested by the IAGA to build this observatory. The first step is to perform a magnetic survey in order to avoid strong magnetic gradients in the location where the absolute and variometers houses will be installed. The next step, the construction of the observatory, includes the selection of special non-magnetic material for the variometer and absolute houses. All materials used were previously tested using a proton magnetometer GSM-19. After construction of the whole infrastructure, the equipment was installed. This Project is a cooperation between Brazilian

  16. Pyroelectric detectors

    NASA Technical Reports Server (NTRS)

    Haller, Eugene E.; Beeman, Jeffrey; Hansen, William L.; Hubbard, G. Scott; Mcmurray, Robert E., Jr.

    1990-01-01

    The multi-agency, long-term Global Change programs, and specifically NASA's Earth Observing system, will require some new and advanced photon detector technology which must be specifically tailored for long-term stability, broad spectral range, cooling constraints, and other parameters. Whereas MCT and GaAs alloy based photovoltaic detectors and detector arrays reach most impressive results to wavelengths as long as 12 microns when cooled to below 70 K, other materials, such as ferroelectrics and pyroelectrics, appear to offer special opportunities beyond 12 microns and above 70 K. These materials have found very broad use in a wide variety of room temperature applications. Little is known about these classes of materials at sub-room temperatures and no photon detector results have been reported. From the limited information available, researchers conclude that the room temperature values of D asterisk greater than or equal to 10(exp 9) cm Hz(exp 1/2)/W may be improved by one to two orders of magnitude upon cooling to temperatures around 70 K. Improvements of up to one order of magnitude appear feasible for temperatures achievable by passive cooling. The flat detector response over a wavelength range reaching from the visible to beyond 50 microns, which is an intrinsic advantage of bolometric devices, makes for easy calibration. The fact that these materials have been developed for reduced temperature applications makes ferro- and pyroelectric materials most attractive candidates for serious exploration.

  17. STS-37 Gamma Ray Observatory (GRO) grappled by RMS

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Backdropped against the Earth's cloud-covered surface, the Gamma Ray Observatory (GRO) with its solar array (SA) panels deployed is grappled by the remote manipulator system (RMS) during STS-37 systems checkout. GRO's four complement instruments are visible: the Energetic Gamma Ray Experiment Telescope (EGRET) (at the bottom); the Imaging Compton Telescope (COMPTEL) (center); the Oriented Scintillation Spectrometer Experiment (OSSE) (top); and Burst and Transient Source Experiment (BATSE) (on four corners).

  18. JUPITER AS A GIANT COSMIC RAY DETECTOR

    SciTech Connect

    Rimmer, P. B.; Stark, C. R.; Helling, Ch.

    2014-06-01

    We explore the feasibility of using the atmosphere of Jupiter to detect ultra-high-energy cosmic rays (UHECRs). The large surface area of Jupiter allows us to probe cosmic rays of higher energies than previously accessible. Cosmic ray extensive air showers in Jupiter's atmosphere could in principle be detected by the Large Area Telescope (LAT) on the Fermi observatory. In order to be observed, these air showers would need to be oriented toward the Earth, and would need to occur sufficiently high in the atmosphere that the gamma rays can penetrate. We demonstrate that, under these assumptions, Jupiter provides an effective cosmic ray ''detector'' area of 3.3 × 10{sup 7} km{sup 2}. We predict that Fermi-LAT should be able to detect events of energy >10{sup 21} eV with fluence 10{sup –7} erg cm{sup –2} at a rate of about one per month. The observed number of air showers may provide an indirect measure of the flux of cosmic rays ≳ 10{sup 20} eV. Extensive air showers also produce a synchrotron signature that may be measurable by Atacama Large Millimeter/submillimeter Array (ALMA). Simultaneous observations of Jupiter with ALMA and Fermi-LAT could be used to provide broad constraints on the energies of the initiating cosmic rays.

  19. SU-E-T-96: Demonstration of a Consistent Method for Correcting Surface Dose Measurements Using Both Solid State and Ionization Chamber Detectors

    SciTech Connect

    Reynolds, T; Gerbi, B; Higgins, P

    2014-06-01

    Purpose: To compare the surface dose (SD) measured using a PTW 30-360 extrapolation chamber with different commonly used dosimeters (Ds): parallel plate ion chambers (ICs): RMI-449 (Attix), Capintec PS-033, PTW 30-329 (Markus) and Memorial; TLD chips (cTLD), TLD powder (pTLD), optically stimulated (OSLs), radiochromic (EXR2) and radiographic (EDR2) films, and to provide an intercomparison correction to Ds for each of them. Methods: Investigations were performed for a 6 MV x-ray beam (Varian Clinac 2300, 10x10 cm{sup 2} open field, SSD = 100 cm). The Ds were placed at the surface of the solid water phantom and at the reference depth dref=1.7cm. The measurements for cTLD, OSLs, EDR2 and EXR2 were corrected to SD using an extrapolation method (EM) indexed to the baseline PTW 30-360 measurements. A consistent use of the EM involved: 1) irradiation of three Ds stacked on top of each other on the surface of the phantom; 2) measurement of the relative dose value for each layer; and, 3) extrapolation of these values to zero thickness. An additional measurement was performed with externally exposed OSLs (eOSLs), that were rotated out of their protective housing. Results: All single Ds measurements overestimated the SD compared with the extrapolation chamber, except for Attix IC. The closest match to the true SD was measured with the Attix IC (− 0.1%), followed by pTLD (0.5%), Capintec (4.5%), Memorial (7.3%), Markus (10%), cTLD (11.8%), eOSL (12.8%), EXR2 (14%), EDR2 (14.8%) and OSL (26%). The EM method of correction for SD worked well for all Ds, except the unexposed OSLs. Conclusion: This EM cross calibration of solid state detectors with an extrapolation or Attix chamber can provide thickness corrections for cTLD, eOSLs, EXR2, and EDR2. Standard packaged OSLs were not found to be simply corrected.

  20. Hinode ``a new solar observatory in space''

    NASA Astrophysics Data System (ADS)

    Tsuneta, S.; Harra, L. K.; Masuda, S.

    2009-05-01

    Since its launch in September 2006, the Japan-US-UK solar physics satellite, Hinode, has continued its observation of the sun, sending back solar images of unprecedented clarity every day. Hinode is equipped with three telescopes, a visible light telescope, an X-ray telescope, and an extreme ultraviolet imaging spectrometer. The Hinode optical telescope has a large primary mirror measuring 50 centimeters in diameter and is the world's largest space telescope for observing the sun and its vector magnetic fields. The impact of Hinode as an optical telescope on solar physics is comparable to that of the Hubble Space Telescope on optical astronomy. While the optical telescope observes the sun's surface, the Hinode X-ray telescope captures images of the corona and the high-temperature flares that range between several million and several tens of millions of degrees. The telescope has captured coronal structures that are clearer than ever. The Hinode EUV imaging spectrometer possesses approximately ten times the sensitivity and four times the resolution of a similar instrument on the SOHO satellite. The source of energy for the sun is in the nuclear fusion reaction that takes place at its core. Here temperature drops closer to the surface, where the temperature measures about 6,000 degrees. Mysteriously, the temperature starts rising again above the surface, and the temperature of the corona is exceptionally high, several millions of degrees. It is as if water were boiling fiercely in a kettle placed on a stove with no fire, inconceivable as it may sound. The phenomenon is referred to as the coronal heating problem, and it is one of the major astronomical mysteries. The Hinode observatory was designed to solve this mystery. It is expected that Hinode would also provide clues to unraveling why strong magnetic fields are formed and how solar flares are triggered. An overview on the initial results from Hinode is presented. Dynamic video pictures captured by Hinode can be

  1. PHASE DETECTOR

    DOEpatents

    Kippenhan, D.O.

    1959-09-01

    A phase detector circuit is described for use at very high frequencies of the order of 50 megacycles. The detector circuit includes a pair of rectifiers inverted relative to each other. One voltage to be compared is applied to the two rectifiers in phase opposition and the other voltage to be compared is commonly applied to the two rectifiers. The two result:ng d-c voltages derived from the rectifiers are combined in phase opposition to produce a single d-c voltage having amplitude and polarity characteristics dependent upon the phase relation between the signals to be compared. Principal novelty resides in the employment of a half-wave transmission line to derive the phase opposing signals from the first voltage to be compared for application to the two rectifiers in place of the transformer commonly utilized for such purpose in phase detector circuits for operation at lower frequency.

  2. Ionization-based detectors for gas chromatography.

    PubMed

    Poole, Colin F

    2015-11-20

    The gas phase ionization detectors are the most widely used detectors for gas chromatography. The column and makeup gases commonly used in gas chromatography are near perfect insulators. This facilitates the detection of a minute number of charge carriers facilitating the use of ionization mechanisms of low efficiency while providing high sensitivity. The main ionization mechanism discussed in this report are combustion in a hydrogen diffusion flame (flame ionization detector), surface ionization in a plasma (thermionic ionization detector), photon ionization (photoionization detector and pulsed discharge helium ionization detector), attachment of thermal electrons (electron-capture detector), and ionization by collision with metastable helium species (helium ionization detector). The design, response characteristics, response mechanism, and suitability for fast gas chromatography are the main features summarized in this report. Mass spectrometric detection and atomic emission detection, which could be considered as ionization detectors of a more sophisticated and complex design, are not discussed in this report. PMID:25757823

  3. Ionization-based detectors for gas chromatography.

    PubMed

    Poole, Colin F

    2015-11-20

    The gas phase ionization detectors are the most widely used detectors for gas chromatography. The column and makeup gases commonly used in gas chromatography are near perfect insulators. This facilitates the detection of a minute number of charge carriers facilitating the use of ionization mechanisms of low efficiency while providing high sensitivity. The main ionization mechanism discussed in this report are combustion in a hydrogen diffusion flame (flame ionization detector), surface ionization in a plasma (thermionic ionization detector), photon ionization (photoionization detector and pulsed discharge helium ionization detector), attachment of thermal electrons (electron-capture detector), and ionization by collision with metastable helium species (helium ionization detector). The design, response characteristics, response mechanism, and suitability for fast gas chromatography are the main features summarized in this report. Mass spectrometric detection and atomic emission detection, which could be considered as ionization detectors of a more sophisticated and complex design, are not discussed in this report.

  4. Hydrogen detector

    DOEpatents

    Kanegae, Naomichi; Ikemoto, Ichiro

    1980-01-01

    A hydrogen detector of the type in which the interior of the detector is partitioned by a metal membrane into a fluid section and a vacuum section. Two units of the metal membrane are provided and vacuum pipes are provided independently in connection to the respective units of the metal membrane. One of the vacuum pipes is connected to a vacuum gauge for static equilibrium operation while the other vacuum pipe is connected to an ion pump or a set of an ion pump and a vacuum gauge both designed for dynamic equilibrium operation.

  5. Microwave detector

    DOEpatents

    Meldner, Heiner W.; Cusson, Ronald Y.; Johnson, Ray M.

    1986-01-01

    A microwave detector (10) is provided for measuring the envelope shape of a microwave pulse comprised of high-frequency oscillations. A biased ferrite (26, 28) produces a magnetization field flux that links a B-dot loop (16, 20). The magnetic field of the microwave pulse participates in the formation of the magnetization field flux. High-frequency insensitive means (18, 22) are provided for measuring electric voltage or current induced in the B-dot loop. The recorded output of the detector is proportional to the time derivative of the square of the envelope shape of the microwave pulse.

  6. Microwave detector

    DOEpatents

    Meldner, H.W.; Cusson, R.Y.; Johnson, R.M.

    1985-02-08

    A microwave detector is provided for measuring the envelope shape of a microwave pulse comprised of high-frequency oscillations. A biased ferrite produces a magnetization field flux that links a B-dot loop. The magnetic field of the microwave pulse participates in the formation of the magnetization field flux. High-frequency insensitive means are provided for measuring electric voltage or current induced in the B-dot loop. The recorded output of the detector is proportional to the time derivative of the square of the envelope shape of the microwave pulse.

  7. Silicon Detectors

    NASA Astrophysics Data System (ADS)

    Sadrozinski, Hartmut

    2014-03-01

    The use of silicon detectors has experienced an exponential growth in accelerator and space based experiments, similar to trends in the semiconductor industry as a whole, usually paraphrased as ``Moore's Law.'' Some of the essentials for this phenomenon will be presented, together with examples of the exciting science results which it enabled. With the establishment of a ``semiconductor culture'' in universities and laboratories around the world, an increased understanding of the sensors results in thinner, faster, more radiation-resistant detectors, spawning an amazing wealth of new technologies and applications, which will be the main subject of the presentation.

  8. Microwave detector

    SciTech Connect

    Meldner, H.W.; Cusson, R.Y.; Johnson, R.M.

    1986-12-02

    A detector is described for measuring the envelope shape of a microwave pulse comprised of high-frequency oscillations, the detector comprising: a B-dot loop linking the magnetic field of the microwave pulse; a biased ferrite, that produces a magnetization field flux that links the B-dot loop. The ferrite is positioned within the B-dot loop so that the magnetic field of the microwave pulse interacts with the ferrite and thereby participates in the formation of the magnetization field flux; and high-frequency insensitive means for measuring electric voltage or current induced in the B-dot loop.

  9. CLEANER-Hydrologic Observatory Joint Science Plan

    NASA Astrophysics Data System (ADS)

    Welty, C.; Dressler, K.; Hooper, R.

    2005-12-01

    modeling and decision-support tools to predict the underlying processes or subsequently forecast the effects of different management strategies. Water is a critical driver for the functioning of all ecosystems and development of human society, and it is a key ingredient for the success of industry, agriculture and, national economy. CLEANER-Hydrologic Observatories will foster cutting-edge science and engineering research that addresses major national needs (public and governmental) related to water and include, for example: (i) water resource problems, such as impaired surface waters, contaminated ground water, water availability for human use and ecosystem needs, floods and floodplain management, urban storm water, agricultural runoff, and coastal hypoxia; (ii) understanding environmental impacts on public health; (iii) achieving a balance of economic and environmental sustainability; (iv) reversing environmental degradation; and (v) protecting against chemical and biological threats. CLEANER (Collaborative Large-scale Engineering Analysis Network for Environmental Research) is an ENG initiative; the Hydrologic Observatory Network is GEO initiative through CUAHSI (Consortium of Universities for the Advancement of Hydrologic Science, Inc.). The two initiatives were merged into a joint, bi-directorate program in December 2004.

  10. ALMA observatory equipped with its first antenna

    NASA Astrophysics Data System (ADS)

    2008-12-01

    High in the Atacama region in northern Chile, one of the world's most advanced telescopes has just passed a major milestone. The first of many state-of-the-art antennas has just been handed over to the Atacama Large Millimeter/submillimeter Array (ALMA) project. ALMA is under construction on the plateau of Chajnantor, at an altitude of 5000 m. The telescope is being built by a global partnership, including ESO as the European partner. ALMA ESO PR Photo 49a/08 ALMA antenna ALMA will initially comprise 66 high precision antennas, with the option to expand in the future. There will be an array of fifty 12-metre antennas, acting together as a single giant telescope, and a compact array composed of 7-metre and 12-metre diameter antennas. With ALMA, astronomers will study the cool Universe -- the molecular gas and tiny dust grains from which stars, planetary systems, galaxies and even life are formed. ALMA will provide new, much-needed insights into the formation of stars and planets, and will reveal distant galaxies in the early Universe, which we see as they were over ten billion years ago. The first 12-metre diameter antenna, built by Mitsubishi Electric Corporation for the National Astronomical Observatory of Japan, one of the ALMA partners, has just been handed over to the observatory. It will shortly be joined by North American and European antennas. "Our Japanese colleagues have produced this state-of-the-art antenna to exacting specifications. We are very excited about the handover because now we can fully equip this antenna for scientific observations," said Thijs de Graauw, ALMA Director. Antennas arriving at the ALMA site undergo a series of tests to ensure that they meet the strict requirements of the telescope. The antennas have surfaces accurate to less than the thickness of a human hair, and can be pointed precisely enough to pick out a golf ball at a distance of 15 km. "ALMA is very important to European astronomers and to ESO, the European partner in

  11. Absolute calibration of the Auger fluorescence detectors

    SciTech Connect

    Bauleo, P.; Brack, J.; Garrard, L.; Harton, J.; Knapik, R.; Meyhandan, R.; Rovero, A.C.; Tamashiro, A.; Warner, D.

    2005-07-01

    Absolute calibration of the Pierre Auger Observatory fluorescence detectors uses a light source at the telescope aperture. The technique accounts for the combined effects of all detector components in a single measurement. The calibrated 2.5 m diameter light source fills the aperture, providing uniform illumination to each pixel. The known flux from the light source and the response of the acquisition system give the required calibration for each pixel. In the lab, light source uniformity is studied using CCD images and the intensity is measured relative to NIST-calibrated photodiodes. Overall uncertainties are presently 12%, and are dominated by systematics.

  12. Omnidirectional Gravitational Radiation Observatory: Proceedings of the First International Workshop

    NASA Astrophysics Data System (ADS)

    Velloso, W. F.; Aguiar, O. D.; Magalhães, N. S.

    1997-08-01

    The Table of Contents for the full book PDF is as follows: * Foreword * Introduction: The OMNI-1 Workshop and the beginning of the International Gravitational Radiation Observatory * Opening Talks * Gravitational radiation sources for Acoustic Detectors * The scientific and technological benefits of gravitational wave research * Operating Second and Third Generation Resonant-Mass Antennas * Performance of the ALLEGRO detector -- and what our experience tells us about spherical detectors * The Perth Niobium resonant mass antenna with microwave parametric transducer * The gravitational wave detectors EXPLORER and NAUTILUS * Gravitational Waves and Astrophysical Sources for the Next Generation Observatory * What is the velocity of gravitational waves? * Superstring Theory: how it change our ideas about the nature of Gravitation * Statistical approach to the G.W. emission from radio pulsars * Gravitational waves from precessing millisecond pulsars * The production rate of compact binary G.W. sources in elliptical galaxies * On the possibility to detect Gravitational Waves from precessing galactic neutron stars * Gravitational wave output of the head-on collision of two black holes * SN as a powerfull source of gravitational radiation * Long thick cosmic strings radiating gravitational waves and particles * Non-Parallel Electric and Magnetic Fields in a gravitational background, stationary G.W. and gravitons * Exact solutions of gravitational waves * Factorization method for linearized quantum gravity at tree-level. Graviton, photon, electron processes * Signal Detection with Resonant-Mass Antennas * Study of coalescing binaries with spherical gravitational waves detectors * Influence of transducer asymmetries on the isotropic response of a spherical gravitational wave antenna * Performances and preliminary results of the cosmic-ray detector associated with NAUTILUS * Possible transducer configurations for a spherical gravitational wave antenna * Detectability of

  13. The Virtual Wave Observatory (VWO)

    NASA Astrophysics Data System (ADS)

    Fung, S. F.; VWO Team

    2008-12-01

    Heliophysics wave data are currently not easily searchable by computers, making identifying pertinent wave data features for analyses and cross comparisons difficult and laborious. Since wave data analysis requires specialized knowledge about waves, which spans the spectrum of microphysics to macrophysics, researchers having varied expertise cannot easily use wave data. To resolve these difficulties and to allow wave data to contribute more fully to Heliophysics research, we are developing a Virtual Wave Observatory (VWO) whose goal is to enable all Heliophysics wave data to become searchable, understandable and usable by the Heliosphysics community. The VWO objective is to enable search of multiple and distributed wave data (from both active and passive measurements). This presentation provides and overview of the VWO, a new VxO component within the emerging distributed Heliophysics data and model environment.

  14. Autonomous Infrastructure for Observatory Operations

    NASA Astrophysics Data System (ADS)

    Seaman, R.

    This is an era of rapid change from ancient human-mediated modes of astronomical practice to a vision of ever larger time domain surveys, ever bigger "big data", to increasing numbers of robotic telescopes and astronomical automation on every mountaintop. Over the past decades, facets of a new autonomous astronomical toolkit have been prototyped and deployed in support of numerous space missions. Remote and queue observing modes have gained significant market share on the ground. Archives and data-mining are becoming ubiquitous; astroinformatic techniques and virtual observatory standards and protocols are areas of active development. Astronomers and engineers, planetary and solar scientists, and researchers from communities as diverse as particle physics and exobiology are collaborating on a vast range of "multi-messenger" science. What then is missing?

  15. HELIO: The Heliophysics Integrated Observatory

    NASA Technical Reports Server (NTRS)

    Bentley, R. D.; Csillaghy, A.; Aboudarham, J.; Jacquey, C.; Hapgood, M. A.; Bocchialini, K.; Messerotti, M.; Brooke, J.; Gallagher, P.; Fox, P.; Hurlburt, N.; Roberts, D. A.; Sanchez Duarte, L.

    2011-01-01

    Heliophysics is a new research field that explores the Sun-Solar System Connection; it requires the joint exploitation of solar, heliospheric, magnetospheric and ionospheric observations. HELIO, the Heliophysics Integrated Observatory, will facilitate this study by creating an integrated e-Infrastructure that has no equivalent anywhere else. It will be a key component of a worldwide effort to integrate heliophysics data and will coordinate closely with international organizations to exploit synergies with complementary domains. HELIO was proposed under a Research Infrastructure call in the Capacities Programme of the European Commission's 7th Framework Programme (FP7). The project was selected for negotiation in January 2009; following a successful conclusion to these, the project started on 1 June 2009 and will last for 36 months.

  16. Goddard Geophysical and Astronomical Observatory

    NASA Technical Reports Server (NTRS)

    Figueroa, Ricardo

    2013-01-01

    This report summarizes the technical parameters and the technical staff of the VLBI system at the fundamental station GGAO. It also gives an overview about the VLBI activities during the report year. The Goddard Geophysical and Astronomical Observatory (GGAO) consists of a 5-meter radio telescope for VLBI, a new 12-meter radio telescope for VLBI2010 development, a 1-meter reference antenna for microwave holography development, an SLR site that includes MOBLAS-7, the NGSLR development system, and a 48" telescope for developmental two-color Satellite Laser Ranging, a GPS timing and development lab, a DORIS system, meteorological sensors, and a hydrogen maser. In addition, we are a fiducial IGS site with several IGS/IGSX receivers. GGAO is located on the east coast of the United States in Maryland. It is approximately 15 miles NNE of Washington, D.C. in Greenbelt, Maryland.

  17. HELIO: A Heliospheric Virtual Observatory

    NASA Astrophysics Data System (ADS)

    Aboudarham, J.; Bentley, R. D.; Csillaghy, A.

    2012-09-01

    HELIO, the Heliophysics Integrated Observatory, is a Research Infrastructure funded under EC's FP7 Capacities Specific Programme. It began in June 2009 for three years. It will provide the heliophysics research community with an integrated e-infrastructure that has no equivalent anywhere else. The project objectives are as follows: - to create a collaborative environment where scientists can discover, understand and model the connection between solar phenomena, interplanetary disturbances and their effects on the planets (esp. the Earth) - to establish a consensus on standards for describing all heliophysical data and champion them within international standards bodies, e.g. the IVOA - to develop new ways to interact with a virtual observatory that are more closely aligned with the way researchers wish to use the data. HELIO is based on a Service-Oriented architecture. For this purpose, HELIO developed a Front End, which facilitates the search for data, using series of search metadata services covering different domains (many Events and Features available; use of context information to refine selection); Services to identify and retrieve observations based on search results (knows which data are stored where and how to access them); Enabling services such as tools to find and track events/phenomena in 4D environment (i.e. including the propagation of phenomena). Services can be used individually or combined through workflow capability. Heliophysics Event Catalogue and Heliophysics Features Catalogue provide a specific access to information concerning phenomena that occur in the Solar system. A semantic-driven approach is used to integrate data from different domains, based on ontology derived from existing data models. Thirteen partners from Europe and US are involved in this project. And although it is not completed, a prototype is already available, which can be accessed through HELIO web site (http://www.helio-vo.eu/).

  18. The Compton Gamma Ray Observatory

    NASA Astrophysics Data System (ADS)

    Gehrels, N.; Chipman, E.; Kniffen, D. A.

    1993-01-01

    The Arthur Holly Compton Gamma Ray Observatory (Compton) was launched by the Space Shuttle Atlantis on 5 April 1991. The spacecraft and instruments are in good health and returning exciting results. The mission provides nearly six orders of magnitude in spectral coverage, from 30 keV to 30 GeV, with sensitivity over the entire range an order of magnitude better than that of previous observations. The 16,000 kilogram observatory contains four instruments on a stabilized platform. The mission began normal operations on 16 May 1991 and is now over half-way through a full-sky survey. The mission duration is expected to be from six to ten years. A Science Support Center has been established at Goddard Space Flight Center for the purpose of supporting a vigorous Guest Investigator Program. New scientific results to date include: (1) the establishment of the isotropy, combined with spatial inhomogeneity, of the distribution of gamma-ray bursts in the sky; (2) the discovery of intense high energy (100 MeV) gamma-ray emission from 3C 279 and other quasars and BL Lac objects, making these the most distant and luminous gamma-ray sources ever detected; (3) one of the first images of a gamma-ray burst; (4) the observation of intense nuclear and position-annihilation gamma-ray lines and neutrons from several large solar flares; and (5) the detection of a third gamma-ray pulsar, plus several other transient and pulsing hard X-ray sources.

  19. TUM Critical Zone Observatory, Germany

    NASA Astrophysics Data System (ADS)

    Völkel, Jörg; Eden, Marie

    2014-05-01

    Founded 2011 the TUM Critical Zone Observatory run by the Technische Universität München and partners abroad is the first CZO within Germany. TUM CZO is both, a scientific as well as an education project. It is a watershed based observatory, but moving behind this focus. In fact, two mountainous areas are integrated: (1) The Ammer Catchment area as an alpine and pre alpine research area in the northern limestone Alps and forelands south of Munich; (2) the Otter Creek Catchment in the Bavarian Forest with a crystalline setting (Granite, Gneiss) as a mid mountainous area near Regensburg; and partly the mountainous Bavarian Forest National Park. The Ammer Catchment is a high energy system as well as a sensitive climate system with past glacial elements. The lithology shows mostly carbonates from Tertiary and Mesozoic times (e.g. Flysch). Source-to-sink processes are characteristic for the Ammer Catchment down to the last glacial Ammer Lake as the regional erosion and deposition base. The consideration of distal depositional environments, the integration of upstream and downstream landscape effects are characteristic for the Ammer Catchment as well. Long term datasets exist in many regards. The Otter Creek catchment area is developed in a granitic environment, rich in saprolites. As a mid mountainous catchment the energy system is facing lower stage. Hence, it is ideal comparing both of them. Both TUM CZO Catchments: The selected catchments capture the depositional environment. Both catchment areas include historical impacts and rapid land use change. Crosscutting themes across both sites are inbuilt. Questions of ability to capture such gradients along climosequence, chronosequence, anthroposequence are essential.

  20. Proposed Ultra-High Sensitivity High-Frequency Gravitational Wave Detector

    NASA Astrophysics Data System (ADS)

    Baker, Robert M. L.; Stephenson, Gary V.; Li, Fangyu

    2008-01-01

    The paper discusses the proposed improvement of a High-Frequency Relic Gravitational Wave (HFRGW) detector designed by Li, Baker, Fang, Stephenson and Chen in order to greatly improve its sensitivity. The improved detector is inspired by the Laser Interferometer Gravitational Observatory or LIGO, but is sensitive to the high-frequency end of the gravitational-wave spectrum. As described in prior papers it utilizes the Gertsenshtein effect, which introduces the conversion of gravitational waves to electromagnetic (EM) waves in the presence of a static magnetic field. Such a conversion, if it leads to photons moving in a direction perpendicular to the plane of the EM waves and the magnetic field, will allow for ultra-high sensitivity HFRGW detection. The use of sensitive microwave, single photon detectors such as a circuit QED and/or the Rydberg Atom Cavity Detector, or off-the-shelf detectors, could lead to such detection. When the EM-detection photons are focused at the microwave detectors by fractal-membrane reflectors sensitivity is also improved. Noise sources external to the HFRGW detector will be eliminated by placing a tight mosaic of superconducting tiles (e.g., YBCO) and/or fractal membranes on the interior surface of the detector's cryogenic containment vessel in order to provide a perfect Faraday cage. Internal thermal noise will be eliminated by means of a microwave absorbing (or reflecting) interior enclosure shaped to conform to a high-intensity continuous microwave Gaussian beam (GB), will reduce any background photon flux (BPF) noise radiated normal to the GB's axis. Such BPF will be further attenuated by a series of microwave absorbing baffles forming tunnels to the sensitive microwave detectors on each side of the GB and at right angles to the static magnetic field. A HFGW detector of bandwidth of 1 KHz to 10 KHz or less in the GHz band has been selected. It is concluded that the utilization of the new ultra-high-sensitivity microwave detectors

  1. BELDATA -- The Database of Belgrade Astronomical Observatory

    NASA Astrophysics Data System (ADS)

    Milovanovic, N.; Popovic, L. C.; Dimitrijevic, M. S.

    The Belgrade Astronomical Database (BELDATA) is an Internet-based database designed to contain Stark broadening parameters, spectra of active galactic nuclei, catalogs of observations done at the Belgrade Observatory and abstracts of papers published in the publications of the observatory.

  2. Colonization of subsurface microbial observatories deployed in young ocean crust

    PubMed Central

    Orcutt, Beth N; Bach, Wolfgang; Becker, Keir; Fisher, Andrew T; Hentscher, Michael; Toner, Brandy M; Wheat, C Geoffrey; Edwards, Katrina J

    2011-01-01

    Oceanic crust comprises the largest hydrogeologic reservoir on Earth, containing fluids in thermodynamic disequilibrium with the basaltic crust. Little is known about microbial ecosystems that inhabit this vast realm and exploit chemically favorable conditions for metabolic activities. Crustal samples recovered from ocean drilling operations are often compromised for microbiological assays, hampering efforts to resolve the extent and functioning of a subsurface biosphere. We report results from the first in situ experimental observatory systems that have been used to study subseafloor life. Experiments deployed for 4 years in young (3.5 Ma) basaltic crust on the eastern flank of the Juan de Fuca Ridge record a dynamic, post-drilling response of crustal microbial ecosystems to changing physical and chemical conditions. Twisted stalks exhibiting a biogenic iron oxyhydroxide signature coated the surface of mineral substrates in the observatories; these are biosignatures indicating colonization by iron oxidizing bacteria during an initial phase of cool, oxic, iron-rich conditions following observatory installation. Following thermal and chemical recovery to warmer, reducing conditions, the in situ microbial structure in the observatory shifted, becoming representative of natural conditions in regional crustal fluids. Firmicutes, metabolic potential of which is unknown but may involve N or S cycling, dominated the post-rebound bacterial community. The archaeal community exhibited an extremely low diversity. Our experiment documented in situ conditions within a natural hydrological system that can pervade over millennia, exemplifying the power of observatory experiments for exploring the subsurface basaltic biosphere, the largest but most poorly understood biotope on Earth. PMID:21107442

  3. Vertex detectors

    SciTech Connect

    Lueth, V.

    1992-07-01

    The purpose of a vertex detector is to measure position and angles of charged particle tracks to sufficient precision so as to be able to separate tracks originating from decay vertices from those produced at the interaction vertex. Such measurements are interesting because they permit the detection of weakly decaying particles with lifetimes down to 10{sup {minus}13} s, among them the {tau} lepton and charm and beauty hadrons. These two lectures are intended to introduce the reader to the different techniques for the detection of secondary vertices that have been developed over the past decades. The first lecture includes a brief introduction to the methods used to detect secondary vertices and to estimate particle lifetimes. It describes the traditional technologies, based on photographic recording in emulsions and on film of bubble chambers, and introduces fast electronic registration of signals derived from scintillating fibers, drift chambers and gaseous micro-strip chambers. The second lecture is devoted to solid state detectors. It begins with a brief introduction into semiconductor devices, and then describes the application of large arrays of strip and pixel diodes for charged particle tracking. These lectures can only serve as an introduction the topic of vertex detectors. Time and space do not allow for an in-depth coverage of many of the interesting aspects of vertex detector design and operation.

  4. A Search for Ultra-High Energy Neutrinos in Highly Inclined Events at the Pierre Auger Observatory

    DOE PAGES

    Abreu, P

    2011-12-30

    The Surface Detector of the Pierre Auger Observatory is sensitive to neutrinos of all flavors above 0.1 EeV. These interact through charged and neutral currents in the atmosphere giving rise to extensive air showers. When interacting deeply in the atmosphere at nearly horizontal incidence, neutrinos can be distinguished from regular hadronic cosmic rays by the broad time structure of their shower signals in the water-Cherenkov detectors. In this paper we present for the first time an analysis based on down-going neutrinos. We describe the search procedure, the possible sources of background, the method to compute the exposure and the associatedmore » systematic uncertainties. No candidate neutrinos have been found in data collected from 1 January 2004 to 31 May 2010. Assuming an E-2 differential energy spectrum the limit on the single-flavor neutrino is E2dN/dE < 1.74 x 10-7 GeV cm-2s-1sr-1 at 90% C.L. in the energy range 1 x 1017eV < E < 1 x 1020 eV.« less

  5. A Search for Ultra-High Energy Neutrinos in Highly Inclined Events at the Pierre Auger Observatory

    SciTech Connect

    Abreu, P

    2011-12-30

    The Surface Detector of the Pierre Auger Observatory is sensitive to neutrinos of all flavors above 0.1 EeV. These interact through charged and neutral currents in the atmosphere giving rise to extensive air showers. When interacting deeply in the atmosphere at nearly horizontal incidence, neutrinos can be distinguished from regular hadronic cosmic rays by the broad time structure of their shower signals in the water-Cherenkov detectors. In this paper we present for the first time an analysis based on down-going neutrinos. We describe the search procedure, the possible sources of background, the method to compute the exposure and the associated systematic uncertainties. No candidate neutrinos have been found in data collected from 1 January 2004 to 31 May 2010. Assuming an E-2 differential energy spectrum the limit on the single-flavor neutrino is E2dN/dE < 1.74 x 10-7 GeV cm-2s-1sr-1 at 90% C.L. in the energy range 1 x 1017eV < E < 1 x 1020 eV.

  6. Cosmic Ray Observatories for Space Weather Studies.

    NASA Astrophysics Data System (ADS)

    González, Xavier

    2016-07-01

    The Mexican Space Weather Service (SCiESMEX) was created in October 2014. Some observatories measure data for the service at different frequencies and particles. Two cosmic ray observatories detect the particle variations attributed to solar emissions, and are an important source of information for the SCiESMEX. The Mexico City Cosmic Ray Observatory consists of a neutron monitor (6-NM-64) and a muon telescope, that detect the hadronic and hard component of the secondary cosmic rays in the atmosphere. It has been in continous operation since 1990. The Sierra Negra Cosmic Ray Observatory consists of a solar neutron telescope and the scintillator cosmic ray telescope. These telescopes can detect the neutrons, generated in solar flares and the hadronic and hard components of the secondary cosmic rays. It has been in continous operation since 2004. We present the two observatories and the capability to detect variations in the cosmic rays, generated by the emissions of the solar activity.

  7. Stratospheric Observatory for Infrared Astronomy (SOFIA)

    NASA Astrophysics Data System (ADS)

    Savage, M. L.; Becklin, E. E.

    2015-09-01

    The joint U.S. and German Stratospheric Observatory for Infrared Astronomy (SOFIA), project has been operating airborne astronomy flights from Palmdale, California since 2011. The observatory consists of a modified 747sp aircraft with a 2.5meter telescope in the tail section. In addition to observing flights out of Palmdale, Ca. this airborne observatory has been able to take advantage of its mobility to observe in the southern hemisphere (New Zealand), to perform multi-wavelength observations of the Super Novae (SN 2014b) in 2014, and to intersect the track of a Pluto Occultation in the southern hemisphere just a few weeks prior to the New Horizons mission fly by of the planet in summer 2015. Science results, observatory operations, current instrument status and participation in future instrument developments, over the lifetime of the observatory will be discussed.

  8. The Pulkovo Observatory on the Centuries' Borderline

    NASA Astrophysics Data System (ADS)

    Abalakin, Viktor K.

    The present paper deals with the development of astrophysical research at the Pulkovo Observatory (now: the Central (Pulkovo) Astronomical Observatory of the Russian Academy of Sciences) at adjacent time periods separated by the threshold between the 19th and the 20th centuries. The Pulkovo Observatory had been inaugurated in 1839. Its traditional field of research work was astrometry. The confirmation of light absorption phenomenon in interstellar space by Friedrich Georg Wilhelm Struve marked the turn of the Observatory's research programs toward astrophysics. New tendencies in the development of contemporaneous astronomy in Russia were pointed out by Otto Struve in his paper “About the Place of Astrophysics in Astronomy” presented in 1866 to the Saint-Petersburg Academy of Sciences. Wide-scale astrophysical studies were performed at Pulkovo Observatory around 1900 during the directorships of Theodore Bredikhin, Oscar Backlund and Aristarchos Belopolsky.

  9. Upper Limit on the Diffuse Flux of Ultrahigh Energy Tau Neutrinos from the Pierre Auger Observatory

    SciTech Connect

    Abraham, J.; Garcia, B.; Otero, L.; Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Conceicao, R.; Goncalves, P.; Pimenta, M.; Santo, C. E.; Tome, B.; Aglietta, M.; Bonino, R.; Castellina, A.; Chiavassa, A.; Fulgione, W.; Gorgi, A.; Hauschildt, T.; Maldera, S.

    2008-05-30

    The surface detector array of the Pierre Auger Observatory is sensitive to Earth-skimming tau neutrinos that interact in Earth's crust. Tau leptons from {nu}{sub {tau}} charged-current interactions can emerge and decay in the atmosphere to produce a nearly horizontal shower with a significant electromagnetic component. The data collected between 1 January 2004 and 31 August 2007 are used to place an upper limit on the diffuse flux of {nu}{sub {tau}} at EeV energies. Assuming an E{sub {nu}}{sup -2} differential energy spectrum the limit set at 90% C.L. is E{sub {nu}}{sup 2}dN{sub {nu}{sub {tau}}}/dE{sub {nu}}<1.3x10{sup -7} GeV cm{sup -2} s{sup -1} sr{sup -1} in the energy range 2x10{sup 17} eV

  10. Upper limit on the diffuse flux of UHE tau neutrinos from the Pierre Auger Observatory

    SciTech Connect

    Collaboration, The Pierre Auger

    2007-12-01

    The surface detector array of the Pierre Auger Observatory is sensitive to Earth-skimming tau-neutrinos {nu}{sub {tau}} that interact in the Earth's crust. Tau leptons from {tau}{sub {tau}} charged-current interactions can emerge and decay in the atmosphere to produce a nearly horizontal shower with a significant electromagnetic component. The data collected between 1 January 2004 and 31 August 2007 is used to place an upper limit on the diffuse flux of {nu}{sub {tau}} at EeV energies. Assuming an E{sub {nu}}{sup -2} differential energy spectrum the limit set at 90 % C.L. is E{sub {nu}}{sup 2} dN{sub {nu}{sub {tau}}}/dE{sub {nu}} < 1.3 x 10{sup -7} GeV cm{sup -2} s{sup -1} sr{sup -1} in the energy range 2 x 10{sup 17} eV < E{sub {nu}} < 2 x 10{sup 19} eV.

  11. Ruggedization of CdZnTe detectors and detector assemblies for radiation detection applications

    NASA Astrophysics Data System (ADS)

    Lu, P. H.; Gomolchuk, P.; Chen, H.; Beitz, D.; Grosser, A. W.

    2015-06-01

    This paper described improvements in the ruggedization of CdZnTe detectors and detector assemblies for use in radiation detection applications. Research included experimenting with various conductive and underfill adhesive material systems suitable for CZT substrates. A detector design with encapsulation patterning was developed to protect detector surfaces and to control spacing between CZT anode and PCB carrier. Robustness of bare detectors was evaluated through temperature cycling and metallization shear testing. Attachment processes using well-chosen adhesives and PCB carrier materials were optimized to improve reliability of detector assemblies, resulted in Improved Attachment Detector Assembly. These detector assemblies were subjected to aggressive temperature cycling, and varying levels of drop/shock and vibration, in accordance with modified JEDEC, ANSI and FedEx testing standards, to assess their ruggedness. Further enhanced detector assembly ruggedization methods were investigated involving adhesive conformal coating, potting and dam filling on detector assemblies, which resulted in the Enhanced Ruggedization Detector Assembly. Large numbers of CZT detectors and detector assemblies with 5 mm and 15 mm thick, over 200 in total, were tested. Their performance was evaluated by exposure to various radioactive sources using comprehensive predefined detector specifications and testing protocols. Detector assemblies from improved attachment and enhanced ruggedization showed stable performances during the harsh environmental condition tests. In conclusion, significant progress has been made in improving the reliability and enhancing the ruggedness of CZT detector assemblies for radiation detection applications deployed in operational environments.

  12. Alaska Volcano Observatory at 20

    NASA Astrophysics Data System (ADS)

    Eichelberger, J. C.

    2008-12-01

    The Alaska Volcano Observatory (AVO) was established in 1988 in the wake of the 1986 Augustine eruption through a congressional earmark. Even within the volcanological community, there was skepticism about AVO. Populations directly at risk in Alaska were small compared to Cascadia, and the logistical costs of installing and maintaining monitoring equipment were much higher. Questions were raised concerning the technical feasibility of keeping seismic stations operating through the long, dark, stormy Alaska winters. Some argued that AVO should simply cover Augustine with instruments and wait for the next eruption there, expected in the mid 90s (but delayed until 2006), rather than stretching to instrument as many volcanoes as possible. No sooner was AVO in place than Redoubt erupted and a fully loaded passenger 747 strayed into the eruption cloud between Anchorage and Fairbanks, causing a powerless glide to within a minute of impact before the pilot could restart two engines and limp into Anchorage. This event forcefully made the case that volcano hazard mitigation is not just about people and infrastructure on the ground, and is particularly important in the heavily traveled North Pacific where options for flight diversion are few. In 1996, new funding became available through an FAA earmark to aggressively extend volcano monitoring far into the Aleutian Islands with both ground-based networks and round-the-clock satellite monitoring. Beyond the Aleutians, AVO developed a monitoring partnership with Russians volcanologists at the Institute of Volcanology and Seismology in Petropavlovsk-Kamchatsky. The need to work together internationally on subduction phenomena that span borders led to formation of the Japan-Kamchatka-Alaska Subduction Processes (JKASP) consortium. JKASP meets approximately biennially in Sapporo, Petropavlovsk, and Fairbanks. In turn, these meetings and support from NSF and the Russian Academy of Sciences led to new international education and

  13. A Bibliometric Analysis of Observatory Publications 2008-2012

    NASA Astrophysics Data System (ADS)

    Crabtree, D. R.

    2015-04-01

    Refereed publications are the primary output of modern observatories. I examine the productivity and impact of a significant number of observatories, as well as some other interesting aspects of observatory papers.

  14. Graduate Astronomy Education in the Early Days of Lick Observatory.

    ERIC Educational Resources Information Center

    Osterbrock, Donald E.

    1980-01-01

    Discusses Lick Observatory's (University of California) early graduate students and graduate program in astronomy. The history of the Lick Observatory and famous astronomy professors and astronomers associated with the Lick Observatory are also discussed. (DS)

  15. The GEOSCOPE broadband seismic observatory

    NASA Astrophysics Data System (ADS)

    Douet, Vincent; Vallée, Martin; Zigone, Dimitri; Bonaimé, Sébastien; Stutzmann, Eléonore; Maggi, Alessia; Pardo, Constanza; Bernard, Armelle; Leroy, Nicolas; Pesqueira, Frédéric; Lévêque, Jean-Jacques; Thoré, Jean-Yves; Bes de Berc, Maxime; Sayadi, Jihane

    2016-04-01

    The GEOSCOPE observatory has provided continuous broadband data to the scientific community for the past 34 years. The 31 operational GEOSCOPE stations are installed in 17 countries, across all continents and on islands throughout the oceans. They are equipped with three component very broadband seismometers (STS1, T240 or STS2) and 24 or 26 bit digitizers (Q330HR). Seismometers are installed with warpless base plates, which decrease long period noise on horizontal components by up to 15dB. All stations send data in real time to the IPGP data center, which transmits them automatically to other data centers (FDSN/IRIS-DMC and RESIF) and tsunami warning centers. In 2016, three stations are expected to be installed or re-installed: in Western China (WUS station), in Saint Pierre and Miquelon Island (off the East coast of Canada) and in Walis and Futuna (SouthWest Pacific Ocean). The waveform data are technically validated by IPGP (25 stations) or EOST (6 stations) in order to check their continuity and integrity. Scientific data validation is also performed by analyzing seismic noise level of the continuous data and by comparing real and synthetic earthquake waveforms (body waves). After these validations, data are archived by the IPGP data center in Paris. They are made available to the international scientific community through different interfaces (see details on http://geoscope.ipgp.fr). Data are duplicated at the FDSN/IRIS-DMC data center and a similar duplication at the French national data center RESIF will be operational in 2016. The GEOSCOPE broadband seismic observatory also provides near-real time information on global moderate-to-large seismicity (above magnitude 5.5-6) through the automated application of the SCARDEC method (Vallée et al., 2011). By using global data from the FDSN - in particular from GEOSCOPE and IRIS/USGS stations -, earthquake source parameters (depth, moment magnitude, focal mechanism, source time function) are determined about 45

  16. EMSO: European Multidisciplinary Seafloor Observatory

    NASA Astrophysics Data System (ADS)

    Favali, P.; Partnership, Emso

    2009-04-01

    EMSO, a Research Infrastructure listed within ESFRI (European Strategy Forum on Research Infrastructures) Roadmap), is the European-scale network of multidisciplinary seafloor observatories from the Arctic to the Black Sea with the scientific objective of long-term real-time monitoring of processes related to geosphere/biosphere/hydrosphere interactions. EMSO will enhance our understanding of processes through long time series appropriate to the scale of the phenomena, constituting the new frontier of studying Earth interior, deep-sea biology and chemistry and ocean processes. EMSO will reply also to the need expressed in the frame of GMES (Global Monitoring for Environment and Security) to develop a marine segment integrated in the in situ and satellite global monitoring system. The EMSO development relays upon the synergy between the scientific community and the industry to improve the European competitiveness with respect to countries like USA/Canada, NEPTUNE, VENUS and MARS projects, Taiwan, MACHO project, and Japan, DONET project. In Europe the development of an underwater network is based on previous EU-funded projects since early '90, and presently supported by EU initiatives. The EMSO infrastructure will constitute the extension to the sea of the land-based networks. Examples of data recorded by seafloor observatories will be presented. EMSO is presently at the stage of Preparatory Phase (PP), funded in the EC FP7 Capacities Programme. The project has started in April 2008 and will last 4 years with the participation of 12 Institutions representing 12 countries. EMSO potential will be significantly increased also with the interaction with other Research Infrastructures addressed to Earth Science. 2. IFREMER-Institut Français de Recherche pour l'exploitation de la mer (France, ref. Roland Person); KDM-Konsortium Deutsche Meeresforschung e.V. (Germany, ref. Christoph Waldmann); IMI-Irish Marine Institute (Ireland, ref. Michael Gillooly); UTM-CSIC-Unidad de

  17. EMSO: European Multidisciplinary Seafloor Observatory

    NASA Astrophysics Data System (ADS)

    Favali, Paolo

    2010-05-01

    EMSO, a Research Infrastructure listed within ESFRI (European Strategy Forum on Research Infrastructures) Roadmap (Report 2006, http://cordis.europa.eu/esfri/roadmap.htm), is the European-scale network of multidisciplinary seafloor observatories from the Arctic to the Black Sea with the scientific objective of long-term real-time monitoring of processes related to geosphere/biosphere/hydrosphere interactions. EMSO will enhance our understanding of processes through long time series appropriate to the scale of the phenomena, constituting the new frontier of studying Earth interior, deep-sea biology and chemistry and ocean processes. The development of an underwater network is based on previous EU-funded projects since early '90 and is being supported by several EU initiatives, as the on-going ESONET-NoE, coordinated by IFREMER (2007-2011, http://www.esonet-emso.org/esonet-noe/), and aims at gathering together the Research Community of the Ocean Observatories. In 2006 the FP7 Capacities Programme launched a call for Preparatory Phase (PP) projects, that will provide the support to create the legal and organisational entities in charge of managing the infrastructures, and coordinating the financial effort among the countries. Under this call the EMSO-PP project was approved in 2007 with the coordination of INGV and the participation of other 11 Institutions of 11 countries. The project has started in April 2008 and will last 4 years. The EMSO is a key-infrastructure both for Ocean Sciences and for Solid Earth Sciences. In this respect it will enhance and complement profitably the capabilities of other European research infrastructures such as EPOS, ERICON-Aurora Borealis, and SIOS. The perspective of the synergy among EMSO and other ESFRI Research Infrastructures will be outlined. EMSO Partners: IFREMER-Institut Français de Recherche pour l'exploitation de la mer (France, ref. Roland Person); KDM-Konsortium Deutsche Meeresforschung e.V. (Germany, ref. Christoph

  18. Virtual Observatories: Requirements for Utility

    NASA Astrophysics Data System (ADS)

    Paxton, L. J.

    2008-12-01

    The principal act that separates science from engineering is that of discovery. Virtual Observatories are a development with great potential for advancing our ability to do science by enabling us to do research effectively and to do research across disciplines. Access to data is one of the factors that enables discovery. A well-designed VO should enable discovery as well as providing for a uniform means by which data are accessed: thus, enabling discovery is the key challenge of a VO in fact it is and should be the principle that distinguishes a VO from a traditional archive. As the number of satellites in the Heliophysics Great observatory starts to decline due to the slower launch cadence and the reduction in funding for extended missions, it becomes more imperative that the community have the means to fully utilize and access the available resources. With the proliferation of low-cost computing and community-based models, cross-disciplinary studies become the new frontier. Many, if not the great majority of research papers are, at this time, confined to a particular discipline. Some of this "stove piping" may be due to the difficulty in accessing products from outside one's own discipline. One would hope and expect that VOs would address this. Two of the principal challenges associated with the vitality of the VOs, aside from the provision of the funds required to maintain the VOs, is 1) the limitation on the availability of data from non-NASA sources and 2) the need for some level of continued support for expertise on the data accessed through the VOs. The first issue is one of culture - some organizations support the view that the data belong to the PI whereas in Heliophysics "data rights" are curtailed. The second issue is to be addressed by the concept of the Resident Archive. This talk will provide an overview of the issues and challenges associated with VOs, Resident Archives, data rights, space missions, and instruments and their associated ground data

  19. Space γ-observatory GAMMA-400 Current Status and Perspectives

    NASA Astrophysics Data System (ADS)

    Galper, A. M.; Bonvicini, V.; Topchiev, N. P.; Adriani, O.; Aptekar, R. L.; Arkhangelskaja, I. V.; Arkhangelskiy, A. I.; Bergstrom, L.; Berti, E.; Bigongiari, G.; Bobkov, S. G.; Boezio, M.; Bogomolov, E. A.; Bonechi, S.; Bongi, M.; Bottai, S.; Castellini, G.; Cattaneo, P. W.; Cumani, P.; Dedenko, G. L.; De Donato, C.; Dogiel, V. A.; Gorbunov, M. S.; Gusakov, Yu. V.; Hnatyk, B. I.; Kadilin, V. V.; Kaplin, V. A.; Kaplun, A. A.; Kheymits, M. D.; Korepanov, V. E.; Larsson, J.; Leonov, A. A.; Loginov, V. A.; Longo, F.; Maestro, P.; Marrocchesi, P. S.; Mikhailov, V. V.; Mocchiutti, E.; Moiseev, A. A.; Mori, N.; Moskalenko, I. V.; Naumov, P. Yu.; Papini, P.; Pearce, M.; Picozza, P.; Rappoldi, A.; Ricciarini, S.; Runtso, M. F.; Ryde, F.; Serdin, O. V.; Sparvoli, R.; Spillantini, P.; Suchkov, S. I.; Tavani, M.; Taraskin, A. A.; Tiberio, A.; Tyurin, E. M.; Ulanov, M. V.; Vacchi, A.; Vannuccini, E.; Vasilyev, G. I.; Yurkin, Yu. T.; Zampa, N.; Zirakashvili, V. N.; Zverev, V. G.

    GAMMA-400 γ-ray telescope is designed to measure fluxes of γ-rays and the electron-positron cosmic ray component possibly generated in annihilation or decay of dark matter particles; to search for and study in detail discrete γ-ray sources, to examine the energy spectra of Galactic and extragalactic diffuse γ-rays, to study γ-ray bursts and γ-rays from the active Sun. GAMMA-400 consists of plastic scintillation anticoincidence top and lateral detectors, converter-tracker, plastic scintillation detectors for the time-of-flight system (TOF), two-part calorimeter (CC1 and CC2), plastic scintillation lateral detectors of calorimeter, plastic scintillation detectors of calorimeter, and neutron detector. The converter-tracker consists of 13 layers of double (x, y) silicon strip coordinate detectors (pitch of 0.08 mm). The first three and final one layers are without tungsten while the middle nine layers are interleaved with nine tungsten conversion foils. The thickness of CC1 and CC2 is 2 X0 (0.1λ0) and 23 X0 (1.1λ0) respectively (where X0 is radiation length and λ0 is nuclear interaction one). The total calorimeter thickness is 25 X0 or 1.2λ0 for vertical incident particles registration and 54 X0 or 2.5λ0 for laterally incident ones. The energy range for γ-rays and electrons (positrons) registration in the main aperture is from ∼0.1 GeV to ∼3.0 TeV. The γ-ray telescope main aperture angular and energy resolutions are respectively ∼0.01 and ∼1% for 102 GeV γ-quanta, the proton rejection factor is ∼5×105. The first three strip layers without tungsten provide the registration of γ-rays down to ∼20 MeV in the main aperture. Also this aperture allows investigating high energy light nuclei fluxes characteristics. Electrons, positrons, light nuclei and gamma-quanta will also register from the lateral directions due to special aperture configuration. Lateral aperture energy resolution is the same as for main aperture for electrons, positrons, light

  20. Angle detector

    NASA Technical Reports Server (NTRS)

    Parra, G. T. (Inventor)

    1978-01-01

    An angle detector for determining a transducer's angular disposition to a capacitive pickup element is described. The transducer comprises a pendulum mounted inductive element moving past the capacitive pickup element. The capacitive pickup element divides the inductive element into two parts L sub 1 and L sub 2 which form the arms of one side of an a-c bridge. Two networks R sub 1 and R sub 2 having a plurality of binary weighted resistors and an equal number of digitally controlled switches for removing resistors from the networks form the arms of the other side of the a-c bridge. A binary counter, controlled by a phase detector, balances the bridge by adjusting the resistance of R sub 1 and R sub 2. The binary output of the counter is representative of the angle.

  1. Flame Detector

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Scientific Instruments, Inc. has now developed a second generation, commercially available instrument to detect flames in hazardous environments, typically refineries, chemical plants and offshore drilling platforms. The Model 74000 detector incorporates a sensing circuit that detects UV radiation in a 100 degree conical field of view extending as far as 250 feet from the instrument. It operates in a bandwidth that makes it virtually 'blind' to solar radiation while affording extremely high sensitivity to ultraviolet flame detection. A 'windowing' technique accurately discriminates between background UV radiation and ultraviolet emitted from an actual flame, hence the user is assured of no false alarms. Model 7410CP is a combination controller and annunciator panel designed to monitor and control as many as 24 flame detectors. *Model 74000 is no longer being manufactured.

  2. The Malaysian Robotic Solar Observatory (P29)

    NASA Astrophysics Data System (ADS)

    Othman, M.; Asillam, M. F.; Ismail, M. K. H.

    2006-11-01

    Robotic observatory with small telescopes can make significant contributions to astronomy observation. They provide an encouraging environment for astronomers to focus on data analysis and research while at the same time reducing time and cost for observation. The observatory will house the primary 50cm robotic telescope in the main dome which will be used for photometry, spectroscopy and astrometry observation activities. The secondary telescope is a robotic multi-apochromatic refractor (maximum diameter: 15 cm) which will be housed in the smaller dome. This telescope set will be used for solar observation mainly in three different wavelengths simultaneously: the Continuum, H-Alpha and Calcium K-line. The observatory is also equipped with an automated weather station, cloud & rain sensor and all-sky camera to monitor the climatic condition, sense the clouds (before raining) as well as to view real time sky view above the observatory. In conjunction with the Langkawi All-Sky Camera, the observatory website will also display images from the Malaysia - Antarctica All-Sky Camera used to monitor the sky at Scott Base Antarctica. Both all-sky images can be displayed simultaneously to show the difference between the equatorial and Antarctica skies. This paper will describe the Malaysian Robotic Observatory including the systems available and method of access by other astronomers. We will also suggest possible collaboration with other observatories in this region.

  3. Telescopes in Education: the Little Thompson Observatory

    NASA Astrophysics Data System (ADS)

    Schweitzer, A. E.; Melsheimer, T. T.

    2004-05-01

    The Little Thompson Observatory is the first community-built E/PO observatory that is accessible to other schools remotely, via the Internet. This observatory is the second member of the Telescopes in Education (TIE) project. The observatory is located on the grounds of Berthoud High School in northern Colorado. The observatory will celebrate its fifth anniversary in summer 2004, and we are planning to expand the building to accommodate our growing number of visitors! We are grateful to have received an IDEAS grant to provide teacher training workshops for K-12 schools to make use of the observatory, including remote observing from classrooms. Students connect to the observatory over the Internet, and then receive the images back on their local computers. We have recently submitted ROSS E/PO proposals toward future teacher programs. A committee of teachers and administrators from the Thompson School District selected these workshops to count towards Incentive Credits (movement on the salary schedule) because the course meets the criteria: "Learning must be directly transferable to the classroom with students and relate to standards, assessment and/or technology." Our program is also accredited by Colorado State University.

  4. The Little Thompson Observatory's Astronomy Education Programs

    NASA Astrophysics Data System (ADS)

    Schweitzer, Andrea E.

    2007-12-01

    The Little Thompson Observatory is a community-built E/PO observatory and is a member of the Telescopes in Education (TIE) project. The observatory is located on the grounds of Berthoud High School in northern Colorado. Annually we have approximately 5,000 visitors, which is roughly equal to the population of the small town of Berthoud, CO. This past year, we have used the funding from our NASA ROSS E/PO grant to expand our teacher workshop programs, and included the baseball-sized meteorite that landed in Berthoud three years ago. Our teacher programs have involved scientists from the Southwest Research Institute and from Fiske Planetarium at CU-Boulder. We thank the NASA ROSS E/PO program for providing this funding! We also held a Colorado Project ASTRO-GEO workshop, and the observatory continues to make high-school astronomy courses available to students from the surrounding school districts. Statewide, this year we helped support the development and construction of three new educational observatories in Colorado, located in Estes Park, Keystone, and Gunnison. The LTO is grateful to have received the recently-retired 24-inch telescope from Mount Wilson Observatory as part of the TIE program. To provide a new home for this historic telescope, we have doubled the size of the observatory and are building a second dome (all with volunteer labor). During 2008 we plan to build a custom pier and refurbish the telescope.

  5. ECHO - the Exoplanet Characterisation Observatory

    NASA Astrophysics Data System (ADS)

    Tessenyi, Marcell

    2010-10-01

    A famous example of Super Earth is GJ 1214b, found by Charbonneau et al. in 2009 as part of the Mearth project: it is believed to be a small (2 Earth masses) ice world. But most of the currently known Exoplanets are of the Hot Jupiter type, large gas giants orbiting bright stars. Attention is now turning to these Super Earths, orbiting low mass late-type stars - many yet to be detected - as they offer the opportunity of obtaining spectral signatures from their atmospheres when found in a transiting or even non-transiting scenarios, via data obtained by ground based and space observatories, compared to simulated climate scenarios. As more of these planets await detection, we estimate from microlensing and radial velocity surveys - which report that Super Earths form 24 to 100% of planets at orbits between 1 and 5 A.U. of their parent stars - and catalogs of stars (RECONS, PMSU, 2MASS), that within 30pc from our sun, over 50 Super Earths transit, orbiting within the Habitable Zone of their host star.

  6. Lyman Alpha Spicule Observatory (LASO)

    NASA Technical Reports Server (NTRS)

    Chamberlin, Phillip C.

    2011-01-01

    The Lyman Alpha Spicule Observatory (LASO) sounding rocket will observe smallscale eruptive events called "Rapid Blue-shifted Events" (RBEs) [Rouppe van der Voort et al., 2009], the on-disk equivalent of Type-II spicules, and extend observations that explore their role in the solar coronal heating problem [De Pontieu et al., 2011]. LASO utilizes a new and novel optical design to simultaneously observe two spatial dimensions at 4.2" spatial resolution (2.1" pixels) over a 2'x2' field of view with high spectral resolution of 66mAngstroms (33mAngstroms pixels) across a broad 20Angstrom spectral window. This spectral window contains three strong chromospheric and transition region emissions and is centered on the strong Hydrogen Lyman-a emission at 1216Angstroms. This instrument makes it possible to obtain new data crucial to the physical understanding of these phenomena and their role in the overall energy and momentum balance from the upper chromosphere to lower corona. LASO was submitted March 2011 in response to the ROSES SHP-LCAS call.

  7. Lyman Alpha Spicule Observatory (LASO)

    NASA Astrophysics Data System (ADS)

    Chamberlin, Phillip C.; Allred, J.; Airapetian, V.; Gong, Q.; Fontenla, J.; McIntosh, S.; de Pontieu, B.

    2011-05-01

    The Lyman Alpha Spicule Observatory (LASO) sounding rocket will observe small-scale eruptive events called "Rapid Blue-shifted Events” (RBEs), the on-disk equivalent of Type-II spicules, and extend observations that explore their role in the solar coronal heating problem. LASO utilizes a new and novel optical design to simultaneously observe two spatial dimensions at 4.2" spatial resolution (2.1” pixels) over a 2'x2' field of view with high spectral resolution of 66mÅ (33mÅ pixels) across a broad 20Å spectral window. This spectral window contains three strong chromospheric and transition region emissions and is centered on the strong Hydrogen Lyman-α emission at 1216Å. This instrument makes it possible to obtain new data crucial to the physical understanding of these phenomena and their role in the overall energy and momentum balance from the upper chromosphere to lower corona. LASO was submitted March 2011 in response to the ROSES SHP-LCAS call.

  8. Lyman Alpha Spicule Observatory (LASO)

    NASA Astrophysics Data System (ADS)

    Chamberlin, P. C.; Allred, J. C.; Airapetian, V.; Gong, Q.; Mcintosh, S. W.; De Pontieu, B.; Fontenla, J. M.

    2011-12-01

    The Lyman Alpha Spicule Observatory (LASO) sounding rocket will observe small-scale eruptive events called "Rapid Blue-shifted Events" (RBEs) [Rouppe van der Voort et al., 2009], the on-disk equivalent of Type-II spicules, and extend observations that explore their role in the solar coronal heating problem [De Pontieu et al., 2011]. LASO utilizes a new and novel optical design to simultaneously observe two spatial dimensions at 4.2" spatial resolution (2.1" pixels) over a 2'x2' field of view with high spectral resolution of 66mÅ (33mÅ pixels) across a broad 20Å spectral window. This spectral window contains three strong chromospheric and transition region emissions and is centered on the strong Hydrogen Lyman-α emission at 1216Å. This instrument makes it possible to obtain new data crucial to the physical understanding of these phenomena and their role in the overall energy and momentum balance from the upper chromosphere to lower corona. LASO was submitted March 2011 in response to the ROSES SHP-LCAS call.

  9. Pulsar Observatory for Students (POS)

    NASA Astrophysics Data System (ADS)

    Joshi, Bhal Chandra; Manoharan, P. K.; Gopakumar, A.; Mitra, D.; Bagchi, Joydeep; Saikia, D. J.

    2012-07-01

    A new program, to initiate motivated undergraduate students to the methodology of pulsar astronomy in particular and radio astronomy in general, is being launched at the Ooty Radio Telescope (ORT). The ORT is a 530 m X 30 m cylindrical radio telescope operating at 325 MHz, having an equatorial mount. Its equatorial mount allows modestly trained students to make pulsar observations without any substantial help from the observatory. Due to its large collecting area, it is a sensitive instrument for pulsar astronomy, capable of detecting a large number of pulsars with short observation time. The program consists of biannual workshops that will introduce scores of students to basics of radio-astronomy and pulsars. It will also train them in the use of the ORT as well as expose them to the future prospects and excitements in the field. The second leg of the program involves live ORT observations by these trained students during various academic breaks. There is a possibility for a follow up program of highly motivated students, selected from this program, to pursue projects of their interest from the data obtained in these sensitive observations. The long term aim of the program is to enlarge the pulsar astronomy community in the country. The presentation will highlight the main features of this program and describe the experience drawn from such programs.

  10. Operations with the FUSE observatory

    NASA Astrophysics Data System (ADS)

    Blair, William P.; Kruk, Jeffrey W.; Moos, Henry W.; Oegerle, William R.

    2003-02-01

    The Far Ultraviolet Spectroscopic Explorer satellite (FUSE) is a NASA Origins mission launched on 1999 June 24 and operated from the Johns Hopkins University Homewood campus in Baltimore, MD. FUSE consists of four aligned telescopes feeding twin far-ultraviolet spectrographs that achieve a spectral resolution of R=20,000 over the 905-1187 Å spectral region. This makes FUSE complementary to the Hubble Space Telescope and of broad general interest to the astronomical community. FUSE is operated as a general-purpose observatory with proposals evaluated and selected by NASA. The FUSE mission concept evolved dramatically over time. The version of FUSE that was built and flown was born out of the "faster, better, cheaper" era, which drove not only the mission development but also plans for operations. Fixed price contracts, a commercial spacecraft, and operations in the University environment were all parts of the low cost strategy. The satellite performs most functions autonomously, with ground contacts limited typically to seven 12-minute contacts per day through a dedicated ground station. All support functions are managed by a staff of 40 scientists and engineers located at Johns Hopkins. In this configuration, we have been able to achieve close to 30% average on-target science efficiency. In short, FUSE is a successful example of the "faster, better, cheaper" philosophy.

  11. Neutrino Detectors

    NASA Astrophysics Data System (ADS)

    von Feilitzsch, Franz; Lanfranchi, Jean-Côme; Wurm, Michael

    The neutrino was postulated by Wolfgang Pauli in the early 1930s, but could only be detected for the first time in the 1950s. Ever since scientists all around the world have worked on the detection and understanding of this particle which so scarcely interacts with matter. Depending on the origin and nature of the neutrino, various types of experiments have been developed and operated. In this entry, we will review neutrino detectors in terms of neutrino energy and associated detection technique as well as the scientific outcome of some selected examples. After a brief historical introduction, the detection of low-energy neutrinos originating from nuclear reactors or from the Earth is used to illustrate the principles and difficulties which are encountered in detecting neutrinos. In the context of solar neutrino spectroscopy, where the neutrino is used as a probe for astrophysics, three different types of neutrino detectors are presented - water Čerenkov, radiochemical, and liquid-scintillator detectors. Moving to higher neutrino energies, we discuss neutrinos produced by astrophysical sources and from accelerators. The entry concludes with an overview of a selection of future neutrino experiments and their scientific goals.

  12. GLOW: The Goddard Lidar Observatory for Winds

    NASA Technical Reports Server (NTRS)

    Gentry, Bruce M.; Chen, Huailin; Li, Steven X.; Einaudi, Franco (Technical Monitor)

    2000-01-01

    GLOW (Goddard Lidar Observatory for Winds) is a mobile Doppler lidar system which uses direct detection Doppler lidar techniques to measure wind profiles from the surface into the lower stratosphere. The system is contained in a modified van to allow deployment in field operations. The lidar system uses a Nd:YAG laser transmitter to measure winds using either aerosol backscatter at 1064 nm or molecular backscatter at 355 nm. The receiver telescope is a 45 cm Dall-Kirkham which is fiber coupled to separate Doppler receivers, one optimized for the aerosol backscatter wind measurement and another optimized for the molecular backscatter wind measurement. The receivers are implementations of the 'double edge' technique and use high spectral resolution Fabry-Perot etalons to measure the Doppler shift. A 45 cm aperture azimuth-over-elevation scanner is mounted on the roof of the van to allow full sky access and a variety of scanning options. GLOW is intended to be used as a deployable field system for studying atmospheric dynamics and transport and can also serve as a testbed to evaluate candidate technologies developed for use in future spaceborne systems. In addition, it can be used for calibration/validation activities following launch of spaceborne wind lidar systems. A description of the mobile system is presented along with the examples of lidar wind profiles obtained with the system.

  13. GLOW- The Goddard Lidar Observatory for Winds

    NASA Technical Reports Server (NTRS)

    Gentry, Bruce M.; Chen, Huailin; Li, Steven X.

    2000-01-01

    GLOW (Goddard Lidar Observatory for Winds) is a mobile Doppler lidar system which uses direct detection Doppler lidar techniques to measure wind profiles from the surface into the lower stratosphere. The system is contained in a modified van to allow deployment in field operations. The lidar system uses a Nd:YAG laser transmitter to measure winds using either aerosol backscatter at 1064 nm or molecular backscatter at 355 nm. The receiver telescope is a 45 cm Dall-Kirkham which is fiber coupled to separate Doppler receivers, one optimized for the aerosol backscatter wind measurement and another optimized for the molecular backscatter wind measurement. The receivers are implementations of the 'double edge' technique and use high spectral resolution Fabry-Perot etalons to measure the Doppler shift. A 45 cm aperture azimuth-over-elevation scanner is mounted on the roof of the van to allow full sky access and a variety of scanning options. GLOW is intended to be used as a deployable field system for studying atmospheric dynamics and transport and can also serve as a testbed to evaluate candidate technologies developed for use in future spaceborne systems. In addition, it can be used for calibration/validation activities following launch of spaceborne wind lidar systems. A description of the mobile system is presented along with the examples of lidar wind profiles obtained with the system.

  14. The Lunar X-ray Observatory (LXO)

    NASA Technical Reports Server (NTRS)

    Porter, F. Scott

    2008-01-01

    X-ray emission from charge exchange recombination between the highly ionized solar wind and neutral material i n Earth's magnetosheath has complicated x-ray observations of celestial objects with x-ray observatories including ROSAT, Chandra, XMM-Newton, and Suzaku. However, the charge-exchange emission can also be used as an important diagnostic of the solar-wind interacting with the magnetosheath. Soft x-ray observations from low-earth orbit or even the highly eccentric orbits of Chandra and XMM-Newton are likely superpositions of the celestial object of interest, the true extra-solar soft x-ray background, geospheric charge exchange, and heliospheric charge exchange. We show that with a small x-ray telescope placed either on the moon, in a similar vein as the Apollo ALSOP instruments, or at a stable orbit near L1, we can begin t o disentangle the complicated emission structure in the soft x-ray band. Here we present initial results of a feasibility study recently funded by NASA t o place a small x-ray telescope on the lunar surface. The telescope operates during lunar night to observe charge exchange interactions between the solar wind and magnetospheric neutrals, between the solar wind and the lunar atmosphere, and an unobstructed view of the soft x-ray background without the geospheric component.

  15. A Simple 2-Transistor Touch or Lick Detector Circuit

    ERIC Educational Resources Information Center

    Slotnick, Burton

    2009-01-01

    Contact or touch detectors in which a subject acts as a switch between two metal surfaces have proven more popular and arguably more useful for recording responses than capacitance switches, photocell detectors, and force detectors. Components for touch detectors circuits are inexpensive and, except for some special purpose designs, can be easily…

  16. The COMPTON Observatory: Reflections on its origins and history

    NASA Astrophysics Data System (ADS)

    Kniffen, D. A.; Gehrels, N.

    1997-05-01

    The Gamma Ray Observatory (GRO) was planned as a mission to make the first comprehensive study of the gamma-ray sky over the full gamma-ray spectrum. It followed on the heels of two successful small astronomy satellites with high energy gamma-ray telescopes, SAS-2 and COS-B, and the High Energy Astronomical Observatory (HEAO) with low-energy gamma-ray detectors. The guideline was to cover the spectrum from the high energy limit of the x-ray domain to the highest energies for which a detectable flux might be reasonably observed. The objective was to include transients as well as persistent sources. The efforts to get such a mission approved stands as a model for developing a consensus of the scientific community for a mission involving a relatively small community of observers. A broad and vigorous guest investigator program was a key element in this effort. The results of the guest investigator program are testimony to the wisdom of this plan. The great success of GRO (now the Compton Observatory) was a result of the dedicated efforts of a few individuals and a project management team that understood how to work with scientists. In spite of increasing budgetary pressure and long delays beyond their control, the project management brought GRO to its successful launch with a minimum of cost growth resulting from the delays. This development period set the stage for what has been one of the most successful scientific programs in NASA's history. The very exciting results presented at this conference by a very broad community of scientists is a testimony to the dedicated efforts of a small group of visionaries with the foresight to see the potential of such a mission.

  17. A Rapid Turnaround Cryogenic Detector Characterization System

    NASA Technical Reports Server (NTRS)

    Benford, Dominic j.; Dipirro, Michael J.; Forgione, Joshua B.; Jackson, Clifton E.; Jackson, Michael L.; Kogut, Al; Moseley, S. Harvey; Shirron, Peter J.

    2004-01-01

    Upcoming major NASA missions such as the Einstein Inflation Probe and the Single Aperture Far-Infrared Observatory require arrays of detectors with thousands of elements, operating at temperatures near l00 mK and sensitive to wavelengths from approx. 100 microns to approx. 3 mm. Such detectors represent a substantial enabling technology for these missions, and must be demonstrated soon in order for them to proceed. In order to make rapid progress on detector development, the cryogenic testing cycle must be made convenient and quick. We have developed a cryogenic detector characterization system capable of testing superconducting detector arrays in formats up to 8 x 32, read out by SQUID multiplexers. The system relies on the cooling of a two-stage adiabatic demagnetization refrigerator immersed in a liquid helium bath. This approach permits a detector to be cooled from 300K to 50 mK in about 4 hours, so that a test cycle begun in the morning will be over by the end of the day. Tine system is modular, with two identical immersible units, so that while one unit is cooling, the second can be reconfigured for the next battery of tests. We describe the design, construction, and performance of this cryogenic detector testing facility.

  18. SOFIA (Stratospheric Observatory For Infrared Astronomy) with Telescope Configuration Changes

    NASA Technical Reports Server (NTRS)

    2001-01-01

    SOFIA (Stratospheric Observatory For Infrared Astronomy) with Telescope Configuration Changes Artwork. Concepts: Based on 18 Years of Experience of Kuiper Airborne Observatory (KAO) Operation, Characteristics, Operations and Science

  19. A Future Large-Aperture UVOIR Space Observatory: Key Technologies and Capabilities

    NASA Technical Reports Server (NTRS)

    Bolcar, Matthew Ryan; Stahle, Carl M.; Balasubramaniam, Kunjithapatham; Clampin, Mark; Feinberg, Lee D.; Mosier, Gary E.; Quijada, Manuel A.; Rauscher, Bernard J.; Redding, David C.; Rioux, Norman M.; Shaklan, Stuart B.; Stahl, H. Philip; Thronson, Harley A.

    2015-01-01

    We present the key technologies and capabilities that will enable a future, large-aperture ultravioletopticalinfrared (UVOIR) space observatory. These include starlight suppression systems, vibration isolation and control systems, lightweight mirror segments, detector systems, and mirror coatings. These capabilities will provide major advances over current and near-future observatories for sensitivity, angular resolution, and starlight suppression. The goals adopted in our study for the starlight suppression system are 10-10 contrast with an inner working angle of 20 milliarcsec and broad bandpass. We estimate that a vibration and isolation control system that achieves a total system vibration isolation of 140 dB for a vibration-isolated mass of 5000 kg is required to achieve the high wavefront error stability needed for exoplanet coronagraphy. Technology challenges for lightweight mirror segments include diffraction-limited optical quality and high wavefront error stability as well as low cost, low mass, and rapid fabrication. Key challenges for the detector systems include visible-blind, high quantum efficiency UV arrays, photon counting visible and NIR arrays for coronagraphic spectroscopy and starlight wavefront sensing and control, and detectors with deep full wells with low persistence and radiation tolerance to enable transit imaging and spectroscopy at all wavelengths. Finally, mirror coatings with high reflectivity ( 90), high uniformity ( 1) and low polarization ( 1) that are scalable to large diameter mirror substrates will be essential for ensuring that both high throughput UV observations and high contrast observations can be performed by the same observatory.

  20. A Linear RFQ Ion Trap for the Enriched Xenon Observatory

    SciTech Connect

    Flatt, B.; Green, M.; Wodin, J.; DeVoe, R.; Fierlinger, P.; Gratta, G.; LePort, F.; Montero Diez, M.; Neilson, R.; O'Sullivan, K.; Pocar, A.; Baussan, E.; Breidenbach, M.; Conley, R.; Fairbank Jr., W.; Farine, J.; Hall, K.; Hallman, D.; Hargrove, C.; Hauger, M.; Hodgson, J.; /Stanford U., Phys. Dept. /Neuchatel U. /SLAC /Colorado State U. /Laurentian U. /Carleton U. /Alabama U.

    2008-01-14

    The design, construction, and performance of a linear radio-frequency ion trap (RFQ) intended for use in the Enriched Xenon Observatory (EXO) are described. EXO aims to detect the neutrinoless double-beta decay of {sup 136}Xe to {sup 136}Ba. To suppress possible backgrounds EXO will complement the measurement of decay energy and, to some extent, topology of candidate events in a Xe filled detector with the identification of the daughter nucleus ({sup 136}Ba). The ion trap described here is capable of accepting, cooling, and confining individual Ba ions extracted from the site of the candidate double-beta decay event. A single trapped ion can then be identified, with a large signal-to-noise ratio, via laser spectroscopy.

  1. Single Ion Trapping for the Enriched Xenon Observatory

    SciTech Connect

    Waldman, Samuel J.; /Stanford U., Phys. Dept. /SLAC

    2006-03-28

    In the last decade, a variety of neutrino oscillation experiments have established that there is a mass difference between neutrino flavors, without determining the absolute neutrino mass scale. The Enriched Xenon Observatory for neutrinoless double beta decay (EXO) will search for the rare decays of xenon to determine the absolute value of the neutrino mass. The experiment uses a novel technique to minimize backgrounds, identifying the decay daughter product in real time using single ion spectroscopy. Here, we describe single ion trapping and spectroscopy compatible with the EXO detector. We extend the technique of single ion trapping in ultrahigh vacuum to trapping in xenon gas. With this technique, EXO will achieve a neutrino mass sensitivity of {approx_equal} .010 eV.

  2. X-ray studies of quasars with the Einstein Observatory

    NASA Technical Reports Server (NTRS)

    Tananbaum, H.; Branduardi, G.; Fabbiano, G.; Feigelson, E.; Giacconi, R.; Henry, J. P.; Avni, Y.; Elvis, M.; Pye, J. P.; Soltan, A.

    1979-01-01

    Results of an investigation of the X-ray properties of quasars conducted using the Einstein Observatory (HEAO 2) are reported. The positions, fluxes and luminosities of 35 known quasars were observed by the Einstein high-resolution imaging detector and the imaging proportional counter. Assuming optical redshifts as valid distance indicators, 0.5-4.5 keV X-ray luminosities ranging from 10 to the 43rd to 10 to the 47 ergs/sec are obtained, with evidence of very little cold gas absorption. Flux variability on a time scale of less than 10,000 sec is observed for the quasar OX 169, which implies a mass between 8 x 10 to the 5th and 2 x 10 to the 8th solar masses for the black hole assumed to be responsible for the emission. Preliminary results of the quasar survey also indicate that quasars contribute significantly to the diffuse X-ray background.

  3. Mass composition measurements at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Molina Bueno, L.; Pierre Auger Collaboration

    2015-11-01

    The Pierre Auger Observatory is the largest ultra-high energy cosmic ray experiment built so far. It is a hybrid detector, since it measures both the fluorescence light emitted while the air showers develop in the atmosphere and the particles reaching the ground. We present the results related to the mass composition of ultra-high energy cosmic rays as obtained from both types of measurements. The depth at which the maximum of the electromagnetic development takes place and its fluctuations are the most sensitive parameters to infer the nature of the cosmic rays. In addition, we present the latest muon measurements that can be used to test and constrain models of hadronic interactions at energies larger than those reached at LHC.

  4. Chandra X-ray Observatory Optical Axis and Aimpoint

    NASA Astrophysics Data System (ADS)

    Zhao, Ping

    2016-01-01

    Chandra X-ray Observatory revolutionized the X-ray astronomy as being the first, and so far the only, X-ray telescope achieving sub-arcsecond resolution. Chandra comprises of three principal elements: the High Resolution Mirror Assembly (HRMA), Pointing Control and Aspect Determination (PCAD) system, and the Science Instrument Module (SIM). To achieve and retain the unprecedented imaging quality, it is critical that these three principal elements stay rigid and stable for the entire life time of the Chandra operation. Tracking the Chandra optical axis and aimpoint with respect to detector positions is the most relevant measurement for understanding telescope stability. The study shows that both the optical axis and the aimpoint has been drifting since Chandra launch. I will discuss the telescope focal-point, optical axis, aimpoint, their positiondrifts during the mission, the impact to Chandra operations, and the permanent default aimpoint, to be implemented in Chandra cycle 18.

  5. Precision Solar Neutrino Measurements with the Sudbury Neutrino Observatory

    SciTech Connect

    Oblath, Noah

    2007-10-26

    The Sudbury Neutrino Observatory (SNO) is the first experiment to measure the total flux of active, high-energy neutrinos from the sun. Results from SNO have solved the long-standing 'Solar Neutrino Problem' by demonstrating that neutrinos change flavor. SNO measured the total neutrino flux with the neutral-current interaction of solar neutrinos with 1000 tonnes of D{sub 2}O. In the first two phases of the experiment we detected the neutron from that interaction by capture on deuterium and capture on chlorine, respectively. In the third phase an array of {sup 3}He proportional counters was deployed in the detector. This allows a measurement of the neutral-current neutrons that is independent of the Cherenkov light detected by the PMT array. We are currently developing a unique, detailed simulation of the current pulses from the proportional-counter array that will be used to help distinguish signal and background pulses.

  6. Improved performance of GaN metal-semiconductor-metal ultraviolet detectors by depositing SiO2 nanoparticles on a GaN surface

    NASA Astrophysics Data System (ADS)

    Sun, Xiaojuan; Li, Dabing; Jiang, Hong; Li, Zhiming; Song, Hang; Chen, Yiren; Miao, Guoqing

    2011-03-01

    GaN metal-semiconductor-metal (MSM) ultraviolet detectors were investigated by depositing different density of SiO2 nanoparticles (SNPs) on the GaN. It was shown that the dark current of the detectors with SNPs was more than one order of magnitude lower than that without SNPs and the peak responsivity was enhanced after deposition of the SNPs. Atomic force microscopy observations indicated that the SNPs usually formed at the termination of screw and mixed dislocations, and further current-voltage measurements showed that the leakage of the Schottky contact for the GaN MSM detector decreased with deposited the SNPs. Moreover, the leakage obeyed the Frenkel-Poole emission model, which meant that the mechanism for improving the performance is the SNPs passivation of the dislocations followed by the reduction in the dark current.

  7. Proximity charge sensing for semiconductor detectors

    SciTech Connect

    Luke, Paul N; Tindall, Craig S; Amman, Mark

    2013-10-08

    A non-contact charge sensor includes a semiconductor detector having a first surface and an opposing second surface. The detector includes a high resistivity electrode layer on the first surface and a low resistivity electrode on the high resistivity electrode layer. A portion of the low resistivity first surface electrode is deleted to expose the high resistivity electrode layer in a portion of the area. A low resistivity electrode layer is disposed on the second surface of the semiconductor detector. A voltage applied between the first surface low resistivity electrode and the second surface low resistivity electrode causes a free charge to drift toward the first or second surface according to a polarity of the free charge and the voltage. A charge sensitive preamplifier coupled to a non-contact electrode disposed at a distance from the exposed high resistivity electrode layer outputs a signal in response to movement of free charge within the detector.

  8. The CHANDRA X-Ray Observatory: Thermal Design, Verification, and Early Orbit Experience

    NASA Technical Reports Server (NTRS)

    Boyd, David A.; Freeman, Mark D.; Lynch, Nicolie; Lavois, Anthony R. (Technical Monitor)

    2000-01-01

    The CHANDRA X-ray Observatory (formerly AXAF), one of NASA's "Great Observatories" was launched aboard the Shuttle in July 1999. CHANDRA comprises a grazing-incidence X-ray telescope of unprecedented focal-length, collecting area and angular resolution -- better than two orders of magnitude improvement in imaging performance over any previous soft X-ray (0.1-10 keV) mission. Two focal-plane instruments, one with a 150 K passively-cooled detector, provide celestial X-ray images and spectra. Thermal control of CHANDRA includes active systems for the telescope mirror and environment and the optical bench, and largely passive systems for the focal plans instruments. Performance testing of these thermal control systems required 1-1/2 years at increasing levels of integration, culminating in thermal-balance testing of the fully-configured observatory during the summer of 1998. This paper outlines details of thermal design tradeoffs and methods for both the Observatory and the two focal-plane instruments, the thermal verification philosophy of the Chandra program (what to test and at what level), and summarizes the results of the instrument, optical system and observatory testing.

  9. Using Virtual Observatories for Heliophysics Research

    NASA Astrophysics Data System (ADS)

    Weigel, Robert S.; Baker, Daniel N.; Roberts, D. Aaron; King, Todd

    2009-11-01

    Scientific satellites, balloons, ground-based instruments, and other observational platforms are producing rich streams of data about the Earth and space. Ensuring widespread access to such data has led to the development of a new type of observatory: the virtual observatory. Existing only in cyberspace, virtual observatories are Web-based interfaces that point users to online data repositories. More important, they allow users not only to access and view multiple sources of information at the same time but also to cross-compare data to build new insights.

  10. Preliminary design study of astronomical detector cooling system

    NASA Technical Reports Server (NTRS)

    Norman, R. H.

    1976-01-01

    The preliminary design of an astronomical detector cooling system for possible use in the NASA C-141 Airborne Infrared Observatory is presented. The system consists of the following elements: supercritical helium tank, Joule-Thomson supply gas conditioner, Joule-Thomson expander (JTX), optical cavity dewar, optical cavity temperature controller, adjustable J-T discharge gas pressure controller, and vacuum pump.

  11. Latest news from the High Altitude Water Cherenkov Observatory

    NASA Astrophysics Data System (ADS)

    González Muñoz, A.; HAWC Collaboration

    2016-07-01

    The High Altitude Water Cherenkov Observatory is an air shower detector designed to study very-high-energy gamma rays (∼ 100 GeV to ∼ 100 TeV). It is located in the Pico de Orizaba National Park, Mexico, at an elevation of 4100 m. HAWC started operations since August 2013 with 111 tanks and in April of 2015 the 300 tanks array was completed. HAWC's unique capabilities, with a field of view of ∼ 2 sr and a high duty cycle of 5%, allow it to survey 2/3 of the sky every day. These features makes HAWC an excellent instrument for searching new TeV sources and for the detection of transient events, like gamma-ray bursts. Moreover, HAWC provides almost continuous monitoring of already known sources with variable gamma-ray fluxes in most of the northern and part of the southern sky. These observations will bring new information about the acceleration processes that take place in astrophysical environments. In this contribution, some of the latest scientific results of the observatory will be presented.

  12. ELVES light intensity studies at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Mussa, Roberto; Maiorana, Carolina

    2016-04-01

    The Pierre Auger Observatory, located in Malargüe (Argentina), is the largest facility (3000 km2) for the study of Ultra High Energy Cosmic Rays (E>1018 eV). The four sites of the Fluorescence Detector (FD) are continuously observing the night sky with moon fraction below 50% (13% duty cycle) with 100 ns time resolution and a space resolution below one degree. The fluorescence light (λ = 300 nm to 420 nm) produced by shower in the atmosphere is proportional to the energy of the primary cosmic ray. The atmospheric optical properties are continuously monitored by the Observatory with a set of dedicated instruments (lidars, cloud cameras, weather stations). The energy of each cosmic ray can therefore be measured with a systematic energy resolution about 14%. After the serendipitous discovery of an ELVES candidate event in 2005, a special trigger has been implemented to detect these phenomena with high efficiency, fully operational since March 2013. Since January 2014 the ELVES candidates are read out with a modified DAQ scheme, to observe the light emission from above the vertical of the causative lightning. This paper will report about the analysis of the correlation between light emission and lightning intensity as recorded by lightning detection networks, on data taken in the last three years of operation.

  13. Latest news from the High Altitude Water Cherenkov Observatory

    NASA Astrophysics Data System (ADS)

    González Muñoz, A.; HAWC Collaboration

    2016-07-01

    The High Altitude Water Cherenkov Observatory is an air shower detector designed to study very-high-energy gamma rays (˜ 100 GeV to ˜ 100 TeV). It is located in the Pico de Orizaba National Park, Mexico, at an elevation of 4100 m. HAWC started operations since August 2013 with 111 tanks and in April of 2015 the 300 tanks array was completed. HAWC's unique capabilities, with a field of view of ˜ 2 sr and a high duty cycle of 5%, allow it to survey 2/3 of the sky every day. These features makes HAWC an excellent instrument for searching new TeV sources and for the detection of transient events, like gamma-ray bursts. Moreover, HAWC provides almost continuous monitoring of already known sources with variable gamma-ray fluxes in most of the northern and part of the southern sky. These observations will bring new information about the acceleration processes that take place in astrophysical environments. In this contribution, some of the latest scientific results of the observatory will be presented.

  14. Intercomparison of Retrospective Radon Detectors

    SciTech Connect

    Field, R W.; Steck, D J.; Parkhurst, Maryann ); Mahaffey, Judith A. ); Alavanja, M C.

    1998-11-01

    We performed both a laboratory and field intercomparison of two novel glass-based retrospective radon detectors previously used in major radon case-control studies performed in Missouri and Iowa. The new detectors estimate retrospective residential radon exposure from the accumulation of a long-lived radon decay product, Pb-210, in glass. The detectors use track registration material in direct contact with glass surfaces to measure the alpha emission of a Pb-210 decay product, Po-210. The detector's track density generation rate (tracks cm{sup -2} hr{sup -1}) is proportional to the surface alpha activity. In the absence of other strong sources of alpha emission in the glass, the implanted surface alpha activity should be proportional to the accumulated Po-210 and hence, the cumulative radon gas exposure. The goals of the intercomparison were to: (1) perform collocated measurements using two different glass-based retrospective radon detectors in a controlled laboratory environment to compare their relative response to implanted polonium in the absence of environmental variation, (2) perform collocated measurements using two different retrospective radon progeny detectors in a variety of residential settings to compare their detection of glass implanted polonium activities, and (3) examine the correlation between track density rates and contemporary radon gas concentrations. The laboratory results suggested that the materials and methods used by the studies produced similar track densities in detectors exposed to the same implanted Po-210 activity. The field phase of the intercomparison found excellent agreement between the track density rates for the two types of retrospective detectors. The correlation between the track density rates and direct contemporary radon concentration measurements was relatively high, considering that no adjustments were performed to account for either the residential depositional environment or glass surface type.

  15. The Design and Performance of the 384: Element Submillimeter Detector Array for SHARC II

    NASA Technical Reports Server (NTRS)

    Moseley, Samuel H.; Allen, Christine; Benford, Dominic; Silverberg, Robert; Staguhn, Johannes; Dowell, Darren; Phillips, Tom

    2003-01-01

    We report on the performance of the SHARC II detector, a 12 x 32 array of ion implanted Si pop-up bolometers. This 384 element detector array was built as a prototype for the High Angular Resolution Widefield Camera (HAWC) for the Stratospheric Observatory for Infrared Astronomy (SOFIA). We will discuss the design process, the characterization of the detectors, and the performance of the array in the SHARC II instrument. SHARC II is now a facility instrument on the Caltech Submillimeter Observatory, providing background-limited imaging at 350 and 450 microns.

  16. The effect of the geomagnetic field on cosmic ray energy estimates and large scale anisotropy searches on data from the Pierre Auger Observatory

    SciTech Connect

    Abreu, P.; Aglietta, M.; Ahn, E.J.; Albuquerque, I.F.M.; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Alvarez Castillo, J.; Alvarez-Muniz, J.; Ambrosio, M.; /Naples U. /INFN, Naples /Nijmegen U., IMAPP

    2011-11-01

    We present a comprehensive study of the influence of the geomagnetic field on the energy estimation of extensive air showers with a zenith angle smaller than 60{sup o}, detected at the Pierre Auger Observatory. The geomagnetic field induces an azimuthal modulation of the estimated energy of cosmic rays up to the {approx} 2% level at large zenith angles. We present a method to account for this modulation of the reconstructed energy. We analyse the effect of the modulation on large scale anisotropy searches in the arrival direction distributions of cosmic rays. At a given energy, the geomagnetic effect is shown to induce a pseudo-dipolar pattern at the percent level in the declination distribution that needs to be accounted for. In this work, we have identified and quantified a systematic uncertainty affecting the energy determination of cosmic rays detected by the surface detector array of the Pierre Auger Observatory. This systematic uncertainty, induced by the influence of the geomagnetic field on the shower development, has a strength which depends on both the zenith and the azimuthal angles. Consequently, we have shown that it induces distortions of the estimated cosmic ray event rate at a given energy at the percent level in both the azimuthal and the declination distributions, the latter of which mimics an almost dipolar pattern. We have also shown that the induced distortions are already at the level of the statistical uncertainties for a number of events N {approx_equal} 32 000 (we note that the full Auger surface detector array collects about 6500 events per year with energies above 3 EeV). Accounting for these effects is thus essential with regard to the correct interpretation of large scale anisotropy measurements taking explicitly profit from the declination distribution.

  17. ALMA Observatory Equipped with its First Antenna

    NASA Astrophysics Data System (ADS)

    2008-12-01

    High in the Atacama region of northern Chile one of the world’s most advanced telescopes has just passed a major milestone. The first of many state-of-the-art antennas has been handed over to the Atacama Large Millimeter/submillimeter Array (ALMA) project. ALMA is being built by a global partnership whose North American partners are led by the National Radio Astronomy Observatory (NRAO). With ALMA, astronomers will study the cool Universe, the molecular gas and tiny dust grains from which stars, planetary systems, galaxies and even life are formed. ALMA will provide new, much-needed insights into the formation of stars and planets, and will reveal distant galaxies in the early Universe, which we see as they were over ten billion years ago. ALMA will initially comprise 66 high-precision antennas, with the option to expand in the future. There will be an array of fifty 12-meter diameter antennas, acting together as a single giant telescope, and a compact array composed of 7-meter and 12-meter antennas. The first 12-meter antenna to be handed over to the observatory was built by Mitsubishi Electric Corporation for the National Astronomical Observatory of Japan, one of the ALMA partners. It will shortly be joined by North American and European antennas. “Our Japanese colleagues have produced this state-of-the-art antenna to exacting specifications. We are very excited about the handover because now we can fully equip this antenna for scientific observations,” said Thijs de Graauw, ALMA Director. Antennas arriving at the ALMA site undergo a series of tests to ensure that they meet the strict requirements of the telescope. The antennas have surfaces accurate to less than the thickness of a human hair, and can be pointed precisely enough to pick out a golf ball at a distance of 9 miles. “The handover of the first Japanese antenna is the crowning achievement of the ALMA Project to date,” said Adrian Russell, the North American ALMA Project Director at NRAO. The

  18. The SIM Lite Astrometric Observatory

    NASA Astrophysics Data System (ADS)

    Unwin, Stephen C.

    2009-05-01

    SIM Lite is an observatory mission dedicated to precision astrometry. With a single measurement accuracy of 1 microarcsecond (µas) and a noise floor below 0.035 µas it will have the capability to do an extensive search for Earth-mass planets in the `habitable zone’ around several dozen of the nearest stars. SIM Lite maintains its wide-angle accuracy of 4 µas for all targets down to V = 19, limited only by observing time. This opens up a wide array of astrophysical problems. As a flexibly pointed instrument, it is a natural complement to sky surveys such as JMAPS and Gaia, and will tackle questions that don't require the acquisition of statistics on a large number of targets. It will provide accurate masses for the first time for a variety of exotic star types, including X-ray binaries; it will study the structure and evolution of our Galaxy through tidal streams from dwarf spheroidals and the trajectories of halo stars and galaxies. Its faint-target capability will enable the use of astrometric and photometric variability as a probe of the disk accretion and jet formation processes in blazars. SIM Lite will have an extensive GO (General Observer) program, open to all categories of astrometric science. The project successfully completed a series of technology milestones in 2005, and is currently under study by by NASA as a flight mission. The research described in this talk was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.

  19. The Solar Dynamics Observatory (SDO)

    NASA Astrophysics Data System (ADS)

    Pesnell, W. Dean; Thompson, B. J.; Chamberlin, P. C.

    2012-01-01

    The Solar Dynamics Observatory (SDO) was launched on 11 February 2010 at 15:23 UT from Kennedy Space Center aboard an Atlas V 401 (AV-021) launch vehicle. A series of apogee-motor firings lifted SDO from an initial geosynchronous transfer orbit into a circular geosynchronous orbit inclined by 28° about the longitude of the SDO-dedicated ground station in New Mexico. SDO began returning science data on 1 May 2010. SDO is the first space-weather mission in NASA’s Living With a Star (LWS) Program. SDO’s main goal is to understand, driving toward a predictive capability, those solar variations that influence life on Earth and humanity’s technological systems. The SDO science investigations will determine how the Sun’s magnetic field is generated and structured, how this stored magnetic energy is released into the heliosphere and geospace as the solar wind, energetic particles, and variations in the solar irradiance. Insights gained from SDO investigations will also lead to an increased understanding of the role that solar variability plays in changes in Earth’s atmospheric chemistry and climate. The SDO mission includes three scientific investigations (the Atmospheric Imaging Assembly (AIA), Extreme Ultraviolet Variability Experiment (EVE), and Helioseismic and Magnetic Imager (HMI)), a spacecraft bus, and a dedicated ground station to handle the telemetry. The Goddard Space Flight Center built and will operate the spacecraft during its planned five-year mission life; this includes: commanding the spacecraft, receiving the science data, and forwarding that data to the science teams. The science investigations teams at Stanford University, Lockheed Martin Solar Astrophysics Laboratory (LMSAL), and University of Colorado Laboratory for Atmospheric and Space Physics (LASP) will process, analyze, distribute, and archive the science data. We will describe the building of SDO and the science that it will provide to NASA.

  20. The Arecibo Observatory Space Academy

    NASA Astrophysics Data System (ADS)

    Rodriguez-Ford, Linda A.; Fernanda Zambrano Marin, Luisa; Aponte Hernandez, Betzaida; Soto, Sujeily; Rivera-Valentin, Edgard G.

    2016-10-01

    The Arecibo Observatory Space Academy (AOSA) is an intense fifteen-week pre-college research program for qualified high school students residing in Puerto Rico, which includes ten days for hands-on, on site research activities. Our mission is to prepare students for their professional careers by allowing them to receive an independent and collaborative research experience on topics related to the multidisciplinary field of space science. Our objectives are to (1) supplement the student's STEM education via inquiry-based learning and indirect teaching methods, (2) immerse students in an ESL environment, further developing their verbal and written presentation skills, and (3) foster in every student an interest in the STEM fields by harnessing their natural curiosity and knowledge in order to further develop their critical thinking and investigation skills. Students interested in participating in the program go through an application, interview and trial period before being offered admission. They are welcomed as candidates the first weeks, and later become cadets while experiencing designing, proposing, and conducting research projects focusing in fields like Physics, Astronomy, Geology, Chemistry, and Engineering. Each individual is evaluated with program compatibility based on peer interaction, preparation, participation, and contribution to class, group dynamics, attitude, challenges, and inquiry. This helps to ensure that specialized attention can be given to students who demonstrate a dedication and desire to learn. Deciding how to proceed in the face of setbacks and unexpected problems is central to the learning experience. At the end of the semester, students present their research to the program mentors, peers, and scientific staff. This year, AOSA students also focused on science communication and were trained by NASA's FameLab. Students additionally presented their research at this year's International Space Development Conference (ISDC), which was held in