WorldWideScience

Sample records for infrared background experiment

  1. The Cosmic Infrared Background Experiment

    Science.gov (United States)

    Bock, James; Battle, J.; Cooray, A.; Hristov, V.; Kawada, M.; Keating, B.; Lee, D.; Matsumoto, T.; Matsuura, S.; Nam, U.; Renbarger, T.; Sullivan, I.; Tsumura, K.; Wada, T.; Zemcov, M.

    2009-01-01

    We are developing the Cosmic Infrared Background ExpeRiment (CIBER) to search for signatures of first-light galaxy emission in the extragalactic background. The first generation of stars produce characteristic signatures in the near-infrared extragalactic background, including a redshifted Ly-cutoff feature and a characteristic fluctuation power spectrum, that may be detectable with a specialized instrument. CIBER consists of two wide-field cameras to measure the fluctuation power spectrum, and a low-resolution and a narrow-band spectrometer to measure the absolute background. The cameras will search for fluctuations on angular scales from 7 arcseconds to 2 degrees, where the first-light galaxy spatial power spectrum peaks. The cameras have the necessary combination of sensitivity, wide field of view, spatial resolution, and multiple bands to make a definitive measurement. CIBER will determine if the fluctuations reported by Spitzer arise from first-light galaxies. The cameras observe in a single wide field of view, eliminating systematic errors associated with mosaicing. Two bands are chosen to maximize the first-light signal contrast, at 1.6 um near the expected spectral maximum, and at 1.0 um; the combination is a powerful discriminant against fluctuations arising from local sources. We will observe regions of the sky surveyed by Spitzer and Akari. The low-resolution spectrometer will search for the redshifted Lyman cutoff feature in the 0.7 - 1.8 um spectral region. The narrow-band spectrometer will measure the absolute Zodiacal brightness using the scattered 854.2 nm Ca II Fraunhofer line. The spectrometers will test if reports of a diffuse extragalactic background in the 1 - 2 um band continues into the optical, or is caused by an under estimation of the Zodiacal foreground. We report performance of the assembled and tested instrument as we prepare for a first sounding rocket flight in early 2009. CIBER is funded by the NASA/APRA sub-orbital program.

  2. COBE diffuse infrared background experiment observations of the galactic bulge

    Science.gov (United States)

    Weiland, J. L.; Arendt, R. G.; Berriman, G. B.; Dwek, E.; Freudenreich, H. T.; Hauser, M. G.; Kelsall, T.; Lisse, C. M.; Mitra, M.; Moseley, S. H.

    1994-01-01

    Low angular resolution maps of the Galactic bulge at 1.25, 2.2, 3.5, and 4.9 micrometers obtained by the Diffuse Infrared Background Experiment (DIRBE) onboard NASA's Cosmic Background Explorer (COBE) are presented. After correction for extinction and subtraction of an empirical model for the Galactic disk, the surface brightness distribution of the bulge resembles a flattened ellipse with a minor-to-major axis ratio of approximately 0.6. The bulge minor axis scale height is found to be 2.1 deg +/- 0.2 deg for all four near-infrared wavelengths. Asymmetries in the longitudinal distribution of bulge brightness contours are qualitatively consistent with those expected for a triaxial bar with its near end in the first Galactic quadrant (0 deg less than l less than 90 deg). There is no evidence for an out-of-plane tilt of such a bar.

  3. THE COSMIC INFRARED BACKGROUND EXPERIMENT (CIBER): THE LOW RESOLUTION SPECTROMETER

    Energy Technology Data Exchange (ETDEWEB)

    Tsumura, K.; Arai, T.; Matsumoto, T.; Matsuura, S.; Murata, K. [Department of Space Astronomy and Astrophysics, Institute of Space and Astronoutical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Battle, J.; Bock, J. [Jet Propulsion Laboratory (JPL), National Aeronautics and Space Administration (NASA), Pasadena, CA 91109 (United States); Brown, S.; Lykke, K.; Smith, A. [Optical Technology Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899 (United States); Cooray, A. [Center for Cosmology, University of California, Irvine, Irvine, CA 92697 (United States); Hristov, V.; Levenson, L. R.; Mason, P. [Department of Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Keating, B.; Renbarger, T. [Department of Physics, University of California, San Diego, San Diego, CA 92093 (United States); Kim, M. G. [Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, D. H.; Nam, U. W. [Korea Astronomy and Space Science Institute (KASI), Daejeon 305-348 (Korea, Republic of); Sullivan, I., E-mail: tsumura@ir.isas.jaxa.jp [Department of Physics, The University of Washington, Seattle, WA 98195 (United States); and others

    2013-08-15

    Absolute spectrophotometric measurements of diffuse radiation at 1 {mu}m to 2 {mu}m are crucial to our understanding of the radiative content of the universe from nucleosynthesis since the epoch of reionization, the composition and structure of the zodiacal dust cloud in our solar system, and the diffuse galactic light arising from starlight scattered by interstellar dust. The Low Resolution Spectrometer (LRS) on the rocket-borne Cosmic Infrared Background Experiment is a {lambda}/{Delta}{lambda} {approx} 15-30 absolute spectrophotometer designed to make precision measurements of the absolute near-infrared sky brightness between 0.75 {mu}m <{lambda} < 2.1 {mu}m. This paper presents the optical, mechanical, and electronic design of the LRS, as well as the ground testing, characterization, and calibration measurements undertaken before flight to verify its performance. The LRS is shown to work to specifications, achieving the necessary optical and sensitivity performance. We describe our understanding and control of sources of systematic error for absolute photometry of the near-infrared extragalactic background light.

  4. THE COSMIC INFRARED BACKGROUND EXPERIMENT (CIBER): A SOUNDING ROCKET PAYLOAD TO STUDY THE NEAR INFRARED EXTRAGALACTIC BACKGROUND LIGHT

    Energy Technology Data Exchange (ETDEWEB)

    Zemcov, M.; Bock, J.; Hristov, V.; Levenson, L. R.; Mason, P. [Department of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Arai, T.; Matsumoto, T.; Matsuura, S.; Tsumura, K.; Wada, T. [Department of Space Astronomy and Astrophysics, Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Battle, J. [Jet Propulsion Laboratory (JPL), National Aeronautics and Space Administration (NASA), Pasadena, CA 91109 (United States); Cooray, A. [Center for Cosmology, University of California, Irvine, Irvine, CA 92697 (United States); Keating, B.; Renbarger, T. [Department of Physics, University of California, San Diego, San Diego, CA 92093 (United States); Kim, M. G. [Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, D. H.; Nam, U. W. [Korea Astronomy and Space Science Institute (KASI), Daejeon 305-348 (Korea, Republic of); Sullivan, I. [Department of Physics, The University of Washington, Seattle, WA 98195 (United States); Suzuki, K., E-mail: zemcov@caltech.edu [Instrument Development Group of Technical Center, Nagoya University, Nagoya, Aichi 464-8602 (Japan)

    2013-08-15

    The Cosmic Infrared Background Experiment (CIBER) is a suite of four instruments designed to study the near infrared (IR) background light from above the Earth's atmosphere. The instrument package comprises two imaging telescopes designed to characterize spatial anisotropy in the extragalactic IR background caused by cosmological structure during the epoch of reionization, a low resolution spectrometer to measure the absolute spectrum of the extragalactic IR background, and a narrow band spectrometer optimized to measure the absolute brightness of the zodiacal light foreground. In this paper we describe the design and characterization of the CIBER payload. The detailed mechanical, cryogenic, and electrical design of the system are presented, including all system components common to the four instruments. We present the methods and equipment used to characterize the instruments before and after flight, and give a detailed description of CIBER's flight profile and configurations. CIBER is designed to be recoverable and has flown four times, with modifications to the payload having been informed by analysis of the first flight data. All four instruments performed to specifications during the subsequent flights, and the scientific data from these flights are currently being analyzed.

  5. Infrared observations of Comet Austin (1990 V) by the COBE/Diffuse Infrared Background Experiment

    Science.gov (United States)

    Lisse, C. M.; Freudenreich, H. T.; Hauser, M. G.; Kelsall, T.; Moseley, S. H.; Reach, W. T.; Silverberg, R. F.

    1994-01-01

    Comet Austin was observed by the Cosmic Background Explorer (COBE)/Diffuse Infrared Background Experiment (DIRBE) with broadband photometry at 1-240 micrometers during the comet's close passage by Earth in 1990 May. A 6 deg long (6 x 10(exp 6) km) dust tail was found at 12 and 25 micrometers, with detailed structure due to variations in particle properties and mass-loss rate. The spectrum of the central 42 x 42 sq arcmin pixel was found to agree with that of a graybody of temperature 309 +/- 5 K and optical depth 7.3 +/- 10(exp -8). Comparison with IUE and ground-based obervations indicates that particles of radius greater than 20 micrometers predominate by surface area. A mass-loss rate of 510 (+510/-205) kg/s and a total tail mass of 7 +/- 2 x 10(exp 10) kg was found for a model dust tail composed of Mie spheres with a differential particle mass distribution dn/d log m approx. m(exp -0.63) and 2:1 silicate:amorphous carbon composition by mass.

  6. THE COSMIC INFRARED BACKGROUND EXPERIMENT (CIBER): THE WIDE-FIELD IMAGERS

    Energy Technology Data Exchange (ETDEWEB)

    Bock, J.; Battle, J. [Jet Propulsion Laboratory (JPL), National Aeronautics and Space Administration (NASA), Pasadena, CA 91109 (United States); Sullivan, I. [Department of Physics, University of Washington, Seattle, WA 98195 (United States); Arai, T.; Matsumoto, T.; Matsuura, S.; Tsumura, K. [Department of Space Astronomy and Astrophysics, Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Cooray, A.; Mitchell-Wynne, K.; Smidt, J. [Center for Cosmology, University of California, Irvine, CA 92697 (United States); Hristov, V.; Lam, A. C.; Levenson, L. R.; Mason, P. [Department of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Keating, B.; Renbarger, T. [Department of Physics, University of California, San Diego, San Diego, CA 92093 (United States); Kim, M. G. [Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, D. H. [Institute of Astronomy and Astrophysics, Academia Sinica, National Taiwan University, Taipei 10617, Taiwan (China); Nam, U. W. [Korea Astronomy and Space Science Institute (KASI), Daejeon 305-348 (Korea, Republic of); Suzuki, K. [Instrument Development Group of Technical Center, Nagoya University, Nagoya, Aichi 464-8602 (Japan); and others

    2013-08-15

    We have developed and characterized an imaging instrument to measure the spatial properties of the diffuse near-infrared extragalactic background light (EBL) in a search for fluctuations from z > 6 galaxies during the epoch of reionization. The instrument is part of the Cosmic Infrared Background Experiment (CIBER), designed to observe the EBL above Earth's atmosphere during a suborbital sounding rocket flight. The imaging instrument incorporates a 2 Degree-Sign Multiplication-Sign 2 Degree-Sign field of view to measure fluctuations over the predicted peak of the spatial power spectrum at 10 arcmin, and 7'' Multiplication-Sign 7'' pixels, to remove lower redshift galaxies to a depth sufficient to reduce the low-redshift galaxy clustering foreground below instrumental sensitivity. The imaging instrument employs two cameras with {Delta}{lambda}/{lambda} {approx} 0.5 bandpasses centered at 1.1 {mu}m and 1.6 {mu}m to spectrally discriminate reionization extragalactic background fluctuations from local foreground fluctuations. CIBER operates at wavelengths where the electromagnetic spectrum of the reionization extragalactic background is thought to peak, and complements fluctuation measurements by AKARI and Spitzer at longer wavelengths. We have characterized the instrument in the laboratory, including measurements of the sensitivity, flat-field response, stray light performance, and noise properties. Several modifications were made to the instrument following a first flight in 2009 February. The instrument performed to specifications in three subsequent flights, and the scientific data are now being analyzed.

  7. Low background infrared (LBIR) facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Low background infrared (LBIR) facility was originally designed to calibrate user supplied blackbody sources and to characterize low-background IR detectors and...

  8. THE COSMIC INFRARED BACKGROUND EXPERIMENT (CIBER): THE NARROW-BAND SPECTROMETER

    Energy Technology Data Exchange (ETDEWEB)

    Korngut, P. M.; Bock, J. [Jet Propulsion Laboratory (JPL), National Aeronautics and Space Administration (NASA), Pasadena, CA 91109 (United States); Renbarger, T.; Keating, B. [Department of Physics, University of California, San Diego, San Diego, CA 92093 (United States); Arai, T.; Matsumoto, T.; Matsuura, S. [Department of Space Astronomy and Astrophysics, Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Battle, J.; Hristov, V.; Lanz, A.; Levenson, L. R.; Mason, P. [Department of Physics, California Institute of Technology, Pasadena, CA 91125 (United States); Brown, S. W.; Lykke, K. R.; Smith, A. W. [Sensor Science Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899 (United States); Cooray, A. [Center for Cosmology, University of California, Irvine, Irvine, CA 92697 (United States); Kim, M. G. [Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, D. H.; Nam, U. W. [Korea Astronomy and Space Science Institute (KASI), Daejeon 305-348 (Korea, Republic of); Shultz, B., E-mail: pkorngut@caltech.edu [Materion Barr Precision Optics and Thin Film Coatings, Westford, MA 01886 (United States); and others

    2013-08-15

    We have developed a near-infrared spectrometer designed to measure the absolute intensity of the solar 854.2 nm Ca II Fraunhofer line, scattered by interplanetary dust, in the zodiacal light (ZL) spectrum. Based on the known equivalent line width in the solar spectrum, this measurement can derive the zodiacal brightness, testing models of the ZL based on morphology that are used to determine the extragalactic background light in absolute photometry measurements. The spectrometer is based on a simple high-resolution tipped filter placed in front of a compact camera with wide-field refractive optics to provide the large optical throughput and high sensitivity required for rocket-borne observations. We discuss the instrument requirements for an accurate measurement of the absolute ZL brightness, the measured laboratory characterization, and the instrument performance in flight.

  9. Diffuse Cosmic Infrared Background Radiation

    Science.gov (United States)

    Dwek, Eli

    2002-01-01

    The diffuse cosmic infrared background (CIB) consists of the cumulative radiant energy released in the processes of structure formation that have occurred since the decoupling of matter and radiation following the Big Bang. In this lecture I will review the observational data that provided the first detections and limits on the CIB, and the theoretical studies explaining the origin of this background. Finally, I will also discuss the relevance of this background to the universe as seen in high energy gamma-rays.

  10. Search for the Cosmic Infrared Background Radiation using COBE Data

    Science.gov (United States)

    Hauser, Michael

    2001-01-01

    This project was initiated to allow completion of the primary investigation of the Diffuse Infrared Background Experiment (DIRBE) on NASA's Cosmic Background Explorer (CORE) mission, and to study the implications of those findings. The Principal Investigator (PI) on this grant was also the Principal Investigator on the DIRBE team. The project had two specific goals: Goal 1: Seek improved limits upon, or detections of, the cosmic infrared background radiation using data from the COBE Diffuse Infrared Background Experiment (DIRBE). Goal 2: Explore the implications of the limits and measured values of the cosmic infrared background for energy releases in the Universe since the formation of the first luminous sources. Both of these goals have been successfully accomplished.

  11. Cosmic Infrared Background Fluctuations and Zodiacal Light

    Science.gov (United States)

    Arendt, Richard G.; Kashlinsky, A.; Moseley, S. H.; Mather, J.

    2016-06-01

    We performed a specific observational test to measure the effect that the zodiacal light can have on measurements of the spatial fluctuations of the near-IR background. Previous estimates of possible fluctuations caused by zodiacal light have often been extrapolated from observations of the thermal emission at longer wavelengths and low angular resolution or from IRAC observations of high-latitude fields where zodiacal light is faint and not strongly varying with time. The new observations analyzed here target the COSMOS field at low ecliptic latitude where the zodiacal light intensity varies by factors of ˜2 over the range of solar elongations at which the field can be observed. We find that the white-noise component of the spatial power spectrum of the background is correlated with the modeled zodiacal light intensity. Roughly half of the measured white noise is correlated with the zodiacal light, but a more detailed interpretation of the white noise is hampered by systematic uncertainties that are evident in the zodiacal light model. At large angular scales (≳100″) where excess power above the white noise is observed, we find no correlation of the power with the modeled intensity of the zodiacal light. This test clearly indicates that the large-scale power in the infrared background is not being caused by the zodiacal light.

  12. Gas leak detection in infrared video with background modeling

    Science.gov (United States)

    Zeng, Xiaoxia; Huang, Likun

    2018-03-01

    Background modeling plays an important role in the task of gas detection based on infrared video. VIBE algorithm is a widely used background modeling algorithm in recent years. However, the processing speed of the VIBE algorithm sometimes cannot meet the requirements of some real time detection applications. Therefore, based on the traditional VIBE algorithm, we propose a fast prospect model and optimize the results by combining the connected domain algorithm and the nine-spaces algorithm in the following processing steps. Experiments show the effectiveness of the proposed method.

  13. Far Infrared Spectrometry of the Cosmic Background Radiation

    Science.gov (United States)

    Mather, J. C.

    1974-01-01

    I describe two experiments to measure the cosmic background radiation near 1 mm wavelength. The first was a ground-based search for spectral lines, made with a Fabry-Perot interferometer and an InSb detector. The second is a measurement of the spectrum from 3 to 18 cm{sup -1}, made with a balloon-borne Fourier transform spectrometer. It is a polarizing Michelson interferometer, cooled in liquid helium, and operated with a germanium bolometer. I give the theory of operation, construction details, and experimental results. The first experiment was successfully completed but the second suffered equipment malfunction on its first flight. I describe the theory of Fourier transformations and give a new understanding of convolutional phase correction computations. I discuss for infrared bolometer calibration procedures, and tabulate test results on nine detectors. I describe methods of improving bolometer sensitivity with immersion optics and with conductive film blackening.

  14. TeV Blazars and Cosmic Infrared Background Radiation

    OpenAIRE

    Aharonian, F. A.

    2001-01-01

    The recent developments in studies of TeV radiation from blazars are highlighted and the implications of these results for derivation of cosmologically important information about the cosmic infrared background radiation are discussed.

  15. Neutrino production by UHECR proton interactions in the infrared background

    Energy Technology Data Exchange (ETDEWEB)

    Stanev, Todor

    2004-08-12

    We discuss the contribution of proton photoproduction interactions in the isotropic infrared/optical background to the cosmic neutrino fluxes. This contribution has a strong dependence on the proton injection energy spectrum, and is essential at high redshifts. It is thus closely correlated with the cosmological evolution of the ultra-high energy proton sources and of the infrared background itself. These interactions may also contribute to the source fluxes of neutrinos if the proton sources are located in regions of high infrared emission and magnetic fields.

  16. Background suppression of infrared small target image based on inter-frame registration

    Science.gov (United States)

    Ye, Xiubo; Xue, Bindang

    2018-04-01

    We propose a multi-frame background suppression method for remote infrared small target detection. Inter-frame information is necessary when the heavy background clutters make it difficult to distinguish real targets and false alarms. A registration procedure based on points matching in image patches is used to compensate the local deformation of background. Then the target can be separated by background subtraction. Experiments show our method serves as an effective preliminary of target detection.

  17. Cosmic far-infrared background at high galactic latitudes

    International Nuclear Information System (INIS)

    Stecker, F.W.; Puget, J.L.; Fazio, G.G.

    1977-01-01

    We predict far-infrared background fluxes from various cosmic sources. These fluxes lie near the high-frequency side of the blackbody radiation spectrum. These sources could account for a significant fraction of the background radiation at frequencies above 400 GHz which might be misinterpreted as a ''Comptonization'' distortion of the blackbody radiation. Particular attention is paid to the possible contributions from external galaxies, from rich clusters of galaxies, and from galactic dust emission

  18. Cosmic far-infrared background at high galactic latitudes

    International Nuclear Information System (INIS)

    Stecker, F.W.; Puget, J.L.; Fazio, G.G.

    1976-12-01

    Far-infrared background fluxes from various cosmic sources are predicted. These fluxes lie near the high-frequency side of the blackbody radiation spectrum. These sources could account for a significant fraction of the background radiation at frequencies above 400 GHz, which might be misinterpreted as a comptonization distortion of the blackbody radiation. Particular attention is paid to the possible contributions from external galaxies, rich clusters of galaxies and from galactic dust emission

  19. Planck 2013 results. XVIII. Gravitational lensing-infrared background correlation

    CERN Document Server

    Ade, P.A.R.; Armitage-Caplan, C.; Arnaud, M.; Ashdown, M.; Atrio-Barandela, F.; Aumont, J.; Baccigalupi, C.; Banday, A.J.; Barreiro, R.B.; Bartlett, J.G.; Basak, S.; Battaner, E.; Benabed, K.; Benoit, A.; Benoit-Levy, A.; Bernard, J.P.; Bersanelli, M.; Bethermin, M.; Bielewicz, P.; Bobin, J.; Bock, J.J.; Bonaldi, A.; Bond, J.R.; Borrill, J.; Bouchet, F.R.; Boulanger, F.; Bridges, M.; Bucher, M.; Burigana, C.; Butler, R.C.; Cardoso, J.F.; Catalano, A.; Challinor, A.; Chamballu, A.; Chiang, L.Y.; Chiang, H.C.; Christensen, P.R.; Church, S.; Clements, D.L.; Colombi, S.; Colombo, L.P.L.; Couchot, F.; Coulais, A.; Crill, B.P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R.D.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Delouis, J.M.; Desert, F.X.; Diego, J.M.; Dole, H.; Donzelli, S.; Dore, O.; Douspis, M.; Dupac, X.; Efstathiou, G.; Ensslin, T.A.; Eriksen, H.K.; Finelli, F.; Forni, O.; Frailis, M.; Franceschi, E.; Galeotta, S.; Ganga, K.; Giard, M.; Giardino, G.; Giraud-Heraud, Y.; Gonzalez-Nuevo, J.; Gorski, K.M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Gudmundsson, J.E.; Hansen, F.K.; Hanson, D.; Harrison, D.; Henrot-Versille, S.; Hernandez-Monteagudo, C.; Herranz, D.; Hildebrandt, S.R.; Hivon, E.; Hobson, M.; Holmes, W.A.; Hornstrup, A.; Hovest, W.; Huffenberger, K.M.; Jaffe, T.R.; Jaffe, A.H.; Jones, W.C.; Juvela, M.; Keihanen, E.; Keskitalo, R.; Kisner, T.S.; Kneissl, R.; Knoche, J.; Knox, L.; Kunz, M.; Kurki-Suonio, H.; Lacasa, F.; Lagache, G.; Lahteenmaki, A.; Lamarre, J.M.; Lasenby, A.; Laureijs, R.J.; Lawrence, C.R.; Leonardi, R.; Leon-Tavares, J.; Lesgourgues, J.; Liguori, M.; Lilje, P.B.; Linden-Vornle, M.; Lopez-Caniego, M.; Lubin, P.M.; Macias-Perez, J.F.; Maffei, B.; Maino, D.; Mandolesi, N.; Maris, M.; Marshall, D.J.; Martin, P.G.; Martinez-Gonzalez, E.; Masi, S.; Matarrese, S.; Matthai, F.; Mazzotta, P.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Mitra, S.; Miville-Deschenes, M.A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Munshi, D.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C.B.; Norgaard-Nielsen, H.U.; Noviello, F.; Novikov, D.; Novikov, I.; Osborne, S.; Oxborrow, C.A.; Paci, F.; Pagano, L.; Pajot, F.; Paoletti, D.; Patanchon, G.; Perdereau, O.; Perotto, L.; Perrotta, F.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Ponthieu, N.; Popa, L.; Poutanen, T.; Pratt, G.W.; Prezeau, G.; Prunet, S.; Puget, J.L.; Rachen, J.P.; Rebolo, R.; Reinecke, M.; Remazeilles, M.; Renault, C.; Ricciardi, S.; Riller, T.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Roudier, G.; Rowan-Robinson, M.; Rusholme, B.; Sandri, M.; Santos, D.; Savini, G.; Scott, D.; Seiffert, M.D.; Serra, P.; Shellard, E.P.S.; Spencer, L.D.; Starck, J.L.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sunyaev, R.; Sureau, F.; Sutton, D.; Suur-Uski, A.S.; Sygnet, J.F.; Tauber, J.A.; Tavagnacco, D.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Tuovinen, J.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vielva, P.; Villa, F.; Vittorio, N.; Wade, L.A.; Wandelt, B.D.; White, S.D.M.; Yvon, D.; Zacchei, A.; Zonca, A.

    2014-01-01

    The multi-frequency capability of the Planck satellite provides information both on the integrated history of star formation (via the cosmic infrared background, or CIB) and on the distribution of dark matter (via the lensing effect on the cosmic microwave background, or CMB). The conjunction of these two unique probes allows us to measure directly the connection between dark and luminous matter in the high redshift (1 1. We measure directly the SFR density with around 2 sigma significance for three redshift bins between z=1 and 7, thus opening a new window into the study of the formation of stars at early times.

  20. Aluminum as a source of background in low background experiments

    Energy Technology Data Exchange (ETDEWEB)

    Majorovits, B., E-mail: bela@mppmu.mpg.de [MPI fuer Physik, Foehringer Ring 6, 80805 Munich (Germany); Abt, I. [MPI fuer Physik, Foehringer Ring 6, 80805 Munich (Germany); Laubenstein, M. [Laboratori Nazionali del Gran Sasso, INFN, S.S.17/bis, km 18 plus 910, I-67100 Assergi (Italy); Volynets, O. [MPI fuer Physik, Foehringer Ring 6, 80805 Munich (Germany)

    2011-08-11

    Neutrinoless double beta decay would be a key to understanding the nature of neutrino masses. The next generation of High Purity Germanium experiments will have to be operated with a background rate of better than 10{sup -5} counts/(kg y keV) in the region of interest around the Q-value of the decay. Therefore, so far irrelevant sources of background have to be considered. The metalization of the surface of germanium detectors is in general done with aluminum. The background from the decays of {sup 22}Na, {sup 26}Al, {sup 226}Ra and {sup 228}Th introduced by this metalization is discussed. It is shown that only a special selection of aluminum can keep these background contributions acceptable.

  1. Infrared image background modeling based on improved Susan filtering

    Science.gov (United States)

    Yuehua, Xia

    2018-02-01

    When SUSAN filter is used to model the infrared image, the Gaussian filter lacks the ability of direction filtering. After filtering, the edge information of the image cannot be preserved well, so that there are a lot of edge singular points in the difference graph, increase the difficulties of target detection. To solve the above problems, the anisotropy algorithm is introduced in this paper, and the anisotropic Gauss filter is used instead of the Gauss filter in the SUSAN filter operator. Firstly, using anisotropic gradient operator to calculate a point of image's horizontal and vertical gradient, to determine the long axis direction of the filter; Secondly, use the local area of the point and the neighborhood smoothness to calculate the filter length and short axis variance; And then calculate the first-order norm of the difference between the local area of the point's gray-scale and mean, to determine the threshold of the SUSAN filter; Finally, the built SUSAN filter is used to convolution the image to obtain the background image, at the same time, the difference between the background image and the original image is obtained. The experimental results show that the background modeling effect of infrared image is evaluated by Mean Squared Error (MSE), Structural Similarity (SSIM) and local Signal-to-noise Ratio Gain (GSNR). Compared with the traditional filtering algorithm, the improved SUSAN filter has achieved better background modeling effect, which can effectively preserve the edge information in the image, and the dim small target is effectively enhanced in the difference graph, which greatly reduces the false alarm rate of the image.

  2. Noise correlations in cosmic microwave background experiments

    Science.gov (United States)

    Dodelson, Scott; Kosowsky, Arthur; Myers, Steven T.

    1995-01-01

    Many analysis of microwave background experiments neglect the correlation of noise in different frequency of polarization channels. We show that these correlations, should they be present, can lead to serve misinterpretation of an experiment. In particular, correlated noise arising from either electronics or atmosphere may mimic a cosmic signal. We quantify how the likelihood function for a given experiment varies with noise correlation, using both simple analytic models and actual data. For a typical microwave background anisotropy experiment, noise correlations at the level of 1% of the overall noise can seriously reduce the significance of a given detection.

  3. Spinning projectile's attitude measurement with LW infrared radiation under sea-sky background

    Science.gov (United States)

    Xu, Miaomiao; Bu, Xiongzhu; Yu, Jing; He, Zilu

    2018-05-01

    With the further development of infrared radiation research in sea-sky background and the requirement of spinning projectile's attitude measurement, the sea-sky infrared radiation field is used to carry out spinning projectile's attitude angle instead of inertial sensors. Firstly, the generation mechanism of sea-sky infrared radiation is analysed. The mathematical model of sea-sky infrared radiation is deduced in LW (long wave) infrared 8 ∼ 14 μm band by calculating the sea surface and sky infrared radiation. Secondly, according to the movement characteristics of spinning projectile, the attitude measurement model of infrared sensors on projectile's three axis is established. And the feasibility of the model is analysed by simulation. Finally, the projectile's attitude calculation algorithm is designed to improve the attitude angle estimation accuracy. The results of semi-physical experiments show that the segmented interactive algorithm estimation error of pitch and roll angle is within ±1.5°. The attitude measurement method is effective and feasible, and provides accurate measurement basis for the guidance of spinning projectile.

  4. Mapping the infrared background radiation from the Shuttle

    Science.gov (United States)

    Koch, D.; Fazio, G. G.; Traub, W. A.; Urban, E. W.; Katz, L.; Rieke, G. H.; Gautier, T. N.; Hoffmann, W. F.; Low, F. J.; Poteet, W.

    1981-01-01

    The Spacelab-2 Small Helium-Cooled Infrared Telescope will be used to map extended astronomical sources of low surface brightness emission, to measure the Shuttle induced environment and to develop techniques for managing large volumes of superfluid helium in space. The instrument is an f/4 15.2-cm Herschelian telescope with ten photoconductor detectors in the focal plane. This paper describes the hardware and software aspects of the instrument with emphasis on mission operations. In particular, a description is given of the observing plan formulated to meet the scientific and engineering objectives, the scan drive system, the precautions in design and operation necessary to prevent the sun, moon, and earth from adversely affecting the observations, the implications of thruster firings, and the on-board experiment computer application software to control the scanning of the telescope and support on-board displays.

  5. Evidence for gravitational lensing of the cosmic microwave background polarization from cross-correlation with the cosmic infrared background.

    Science.gov (United States)

    Ade, P A R; Akiba, Y; Anthony, A E; Arnold, K; Atlas, M; Barron, D; Boettger, D; Borrill, J; Borys, C; Chapman, S; Chinone, Y; Dobbs, M; Elleflot, T; Errard, J; Fabbian, G; Feng, C; Flanigan, D; Gilbert, A; Grainger, W; Halverson, N W; Hasegawa, M; Hattori, K; Hazumi, M; Holzapfel, W L; Hori, Y; Howard, J; Hyland, P; Inoue, Y; Jaehnig, G C; Jaffe, A; Keating, B; Kermish, Z; Keskitalo, R; Kisner, T; Le Jeune, M; Lee, A T; Leitch, E M; Linder, E; Lungu, M; Matsuda, F; Matsumura, T; Meng, X; Miller, N J; Morii, H; Moyerman, S; Myers, M J; Navaroli, M; Nishino, H; Paar, H; Peloton, J; Poletti, D; Quealy, E; Rebeiz, G; Reichardt, C L; Richards, P L; Ross, C; Rotermund, K; Schanning, I; Schenck, D E; Sherwin, B D; Shimizu, A; Shimmin, C; Shimon, M; Siritanasak, P; Smecher, G; Spieler, H; Stebor, N; Steinbach, B; Stompor, R; Suzuki, A; Takakura, S; Tikhomirov, A; Tomaru, T; Wilson, B; Yadav, A; Zahn, O

    2014-04-04

    We reconstruct the gravitational lensing convergence signal from cosmic microwave background (CMB) polarization data taken by the Polarbear experiment and cross-correlate it with cosmic infrared background maps from the Herschel satellite. From the cross spectra, we obtain evidence for gravitational lensing of the CMB polarization at a statistical significance of 4.0σ and indication of the presence of a lensing B-mode signal at a significance of 2.3σ. We demonstrate that our results are not biased by instrumental and astrophysical systematic errors by performing null tests, checks with simulated and real data, and analytical calculations. This measurement of polarization lensing, made via the robust cross-correlation channel, not only reinforces POLARBEAR auto-correlation measurements, but also represents one of the early steps towards establishing CMB polarization lensing as a powerful new probe of cosmology and astrophysics.

  6. Demonstration of Cosmic Microwave Background Delensing Using the Cosmic Infrared Background.

    Science.gov (United States)

    Larsen, Patricia; Challinor, Anthony; Sherwin, Blake D; Mak, Daisy

    2016-10-07

    Delensing is an increasingly important technique to reverse the gravitational lensing of the cosmic microwave background (CMB) and thus reveal primordial signals the lensing may obscure. We present a first demonstration of delensing on Planck temperature maps using the cosmic infrared background (CIB). Reversing the lensing deflections in Planck CMB temperature maps using a linear combination of the 545 and 857 GHz maps as a lensing tracer, we find that the lensing effects in the temperature power spectrum are reduced in a manner consistent with theoretical expectations. In particular, the characteristic sharpening of the acoustic peaks of the temperature power spectrum resulting from successful delensing is detected at a significance of 16σ, with an amplitude of A_{delens}=1.12±0.07 relative to the expected value of unity. This first demonstration on data of CIB delensing, and of delensing techniques in general, is significant because lensing removal will soon be essential for achieving high-precision constraints on inflationary B-mode polarization.

  7. Research on cloud background infrared radiation simulation based on fractal and statistical data

    Science.gov (United States)

    Liu, Xingrun; Xu, Qingshan; Li, Xia; Wu, Kaifeng; Dong, Yanbing

    2018-02-01

    Cloud is an important natural phenomenon, and its radiation causes serious interference to infrared detector. Based on fractal and statistical data, a method is proposed to realize cloud background simulation, and cloud infrared radiation data field is assigned using satellite radiation data of cloud. A cloud infrared radiation simulation model is established using matlab, and it can generate cloud background infrared images for different cloud types (low cloud, middle cloud, and high cloud) in different months, bands and sensor zenith angles.

  8. Background characterization for the GERDA experiment

    Energy Technology Data Exchange (ETDEWEB)

    Becerici-Schmidt, Neslihan [Max-Planck-Institut fuer Physik, Muenchen (Germany); Collaboration: GERDA-Collaboration

    2013-07-01

    The GERmanium Detector Array (Gerda) experiment at the LNGS laboratory of INFN searches for the neutrinoless double beta (0νββ) decay of {sup 76}Ge. A discovery of this decay can greatly advance our knowledge on the nature and properties of neutrinos. The current best limit on the half-life of {sup 76}Ge 0νββ decay is 1.9 . 10{sup 25} years (90% C.L.). In order to increase the sensitivity on the half-life with respect to past experiments, the background rate in the energy region of interest (ROI) around Q{sub ββ} = 2039 keV has been reduced by a factor 10. Gerda started data-taking with the full set of Phase I detectors in November 2011. Identification of the background in the first phase of the experiment is of major importance to further mitigate the background for Gerda Phase II. An analysis of the Phase I data resulted in a good understanding of the individual components in the Gerda background spectrum. The background components in the ROI have been identified to be mainly due to β- and γ-induced events originating from {sup 214}Bi ({sup 238}U-series), {sup 208}Tl ({sup 232}Th-series), {sup 42}K (progeny of {sup 42}Ar) and α-induced events coming from isotopes in the {sup 226}Ra decay chain. A background decomposition in the ROI will be presented, with a special emphasis on the contribution from α-induced events.

  9. Background modeling for the GERDA experiment

    Science.gov (United States)

    Becerici-Schmidt, N.; Gerda Collaboration

    2013-08-01

    The neutrinoless double beta (0νββ) decay experiment GERDA at the LNGS of INFN has started physics data taking in November 2011. This paper presents an analysis aimed at understanding and modeling the observed background energy spectrum, which plays an essential role in searches for a rare signal like 0νββ decay. A very promising preliminary model has been obtained, with the systematic uncertainties still under study. Important information can be deduced from the model such as the expected background and its decomposition in the signal region. According to the model the main background contributions around Qββ come from 214Bi, 228Th, 42K, 60Co and α emitting isotopes in the 226Ra decay chain, with a fraction depending on the assumed source positions.

  10. Background modeling for the GERDA experiment

    Energy Technology Data Exchange (ETDEWEB)

    Becerici-Schmidt, N. [Max-Planck-Institut für Physik, München (Germany); Collaboration: GERDA Collaboration

    2013-08-08

    The neutrinoless double beta (0νββ) decay experiment GERDA at the LNGS of INFN has started physics data taking in November 2011. This paper presents an analysis aimed at understanding and modeling the observed background energy spectrum, which plays an essential role in searches for a rare signal like 0νββ decay. A very promising preliminary model has been obtained, with the systematic uncertainties still under study. Important information can be deduced from the model such as the expected background and its decomposition in the signal region. According to the model the main background contributions around Q{sub ββ} come from {sup 214}Bi, {sup 228}Th, {sup 42}K, {sup 60}Co and α emitting isotopes in the {sup 226}Ra decay chain, with a fraction depending on the assumed source positions.

  11. The projected background for the CUORE experiment

    Energy Technology Data Exchange (ETDEWEB)

    Alduino, C.; Avignone, F.T.; Chott, N.; Creswick, R.J.; Rosenfeld, C.; Wilson, J. [University of South Carolina, Department of Physics and Astronomy, Columbia, SC (United States); Alfonso, K.; Hickerson, K.P.; Huang, H.Z.; Sakai, M.; Schmidt, J.; Trentalange, S.; Zhu, B.X. [University of California, Department of Physics and Astronomy, Los Angeles, CA (United States); Artusa, D.R.; Rusconi, C. [University of South Carolina, Department of Physics and Astronomy, Columbia, SC (United States); INFN-Laboratori Nazionali del Gran Sasso, L' Aquila (Italy); Azzolini, O.; Camacho, A.; Keppel, G.; Palmieri, V.; Pira, C. [INFN-Laboratori Nazionali di Legnaro, Padua (Italy); Banks, T.I.; Drobizhev, A.; Freedman, S.J.; Hennings-Yeomans, R.; Kolomensky, Yu.G.; Wagaarachchi, S.L. [University of California, Department of Physics, Berkeley, CA (United States); Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States); Bari, G.; Deninno, M.M. [INFN-Sezione di Bologna, Bologna (Italy); Beeman, J.W. [Lawrence Berkeley National Laboratory, Materials Science Division, Berkeley, CA (United States); Bellini, F.; Cosmelli, C.; Ferroni, F.; Piperno, G. [Sapienza Universita di Roma, Dipartimento di Fisica, Rome (Italy); INFN-Sezione di Roma, Rome (Italy); Benato, G.; Singh, V. [University of California, Department of Physics, Berkeley, CA (United States); Bersani, A.; Caminata, A. [INFN-Sezione di Genova, Genoa (Italy); Biassoni, M.; Brofferio, C.; Capelli, S.; Carniti, P.; Cassina, L.; Chiesa, D.; Clemenza, M.; Faverzani, M.; Fiorini, E.; Gironi, L.; Gotti, C.; Maino, M.; Nastasi, M.; Nucciotti, A.; Pavan, M.; Pozzi, S.; Sisti, M.; Terranova, F.; Zanotti, L. [Universita di Milano-Bicocca, Dipartimento di Fisica, Milan (Italy); INFN-Sezione di Milano Bicocca, Milan (Italy); Branca, A.; Taffarello, L. [INFN-Sezione di Padova, Padua (Italy); Bucci, C.; Cappelli, L.; D' Addabbo, A.; Gorla, P.; Pattavina, L.; Pirro, S.; Laubenstein, M. [INFN-Laboratori Nazionali del Gran Sasso, L' Aquila (Italy); Canonica, L. [INFN-Laboratori Nazionali del Gran Sasso, L' Aquila (Italy); Massachusetts Institute of Technology, Cambridge, MA (United States); Cao, X.G.; Fang, D.Q.; Ma, Y.G.; Wang, H.W.; Zhang, G.Q. [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai (China); Carbone, L.; Cremonesi, O.; Ferri, E.; Giachero, A.; Pessina, G.; Previtali, E. [INFN-Sezione di Milano Bicocca, Milan (Italy); Cardani, L.; Casali, N.; Dafinei, I.; Morganti, S.; Mosteiro, P.J.; Pettinacci, V.; Tomei, C.; Vignati, M. [INFN-Sezione di Roma, Rome (Italy); Copello, S.; Di Domizio, S.; Fernandes, G.; Marini, L.; Pallavicini, M. [INFN-Sezione di Genova, Genoa (Italy); Universita di Genova, Dipartimento di Fisica, Genoa (Italy); Cushman, J.S.; Davis, C.J.; Heeger, K.M.; Lim, K.E.; Maruyama, R.H. [Yale University, Department of Physics, New Haven, CT (United States); Dell' Oro, S. [INFN-Laboratori Nazionali del Gran Sasso, L' Aquila (Italy); INFN-Gran Sasso Science Institute, L' Aquila (Italy); Di Vacri, M.L.; Santone, D. [INFN-Laboratori Nazionali del Gran Sasso, L' Aquila (Italy); Universita dell' Aquila, Dipartimento di Scienze Fisiche e Chimiche, L' Aquila (Italy); Franceschi, M.A.; Ligi, C.; Napolitano, T. [INFN-Laboratori Nazionali di Frascati, Rome (Italy); Fujikawa, B.K.; Mei, Y.; Schmidt, B.; Smith, A.R.; Welliver, B. [Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States); Giuliani, A.; Novati, V.; Tenconi, M. [Universit Paris-Saclay, CSNSM, Univ. Paris-Sud, CNRS/IN2P3, Orsay (France); Gladstone, L.; Leder, A.; Ouellet, J.L.; Winslow, L.A. [Massachusetts Institute of Technology, Cambridge, MA (United States); Gutierrez, T.D. [California Polytechnic State University, Physics Department, San Luis Obispo, CA (United States); Haller, E.E. [Lawrence Berkeley National Laboratory, Materials Science Division, Berkeley, CA (United States); University of California, Department of Materials Science and Engineering, Berkeley, CA (United States); Han, K. [Shanghai Jiao Tong University, Department of Physics and Astronomy, Shanghai (China); Hansen, E. [University of California, Department of Physics and Astronomy, Los Angeles, CA (United States); Massachusetts Institute of Technology, Cambridge, MA (United States); Kadel, R. [Lawrence Berkeley National Laboratory, Physics Division, Berkeley, CA (United States); Martinez, M. [Sapienza Universita di Roma, Dipartimento di Fisica, Rome (Italy); INFN-Sezione di Roma, Rome (Italy); Universidad de Zaragoza, Laboratorio de Fisica Nuclear y Astroparticulas, Zaragoza (Spain); Moggi, N. [INFN-Sezione di Bologna, Bologna (Italy); Alma Mater Studiorum-Universita di Bologna, Dipartimento di Scienze per la Qualita della Vita, Bologna (Italy); Nones, C. [CEA/Saclay, Service de Physique des Particules, Gif-sur-Yvette (France); Norman, E.B.; Wang, B.S. [Lawrence Livermore National Laboratory, Livermore, CA (United States); University of California, Department of Nuclear Engineering, Berkeley, CA (United States); O' Donnell, T. [Virginia Polytechnic Institute and State University, Center for Neutrino Physics, Blacksburg, VA (United States); Pagliarone, C.E. [INFN-Laboratori Nazionali del Gran Sasso, L' Aquila (Italy); Universita degli Studi di Cassino e del Lazio Meridionale, Dipartimento di Ingegneria Civile e Meccanica, Cassino (Italy); Sangiorgio, S.; Scielzo, N.D. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Wise, T. [Yale University, Department of Physics, New Haven, CT (United States); University of Wisconsin, Department of Physics, Madison, WI (United States); Woodcraft, A. [University of Edinburgh, SUPA, Institute for Astronomy, Edinburgh (United Kingdom); Zimmermann, S. [Lawrence Berkeley National Laboratory, Engineering Division, Berkeley, CA (United States); Zucchelli, S. [INFN-Sezione di Bologna, Bologna (Italy); Alma Mater Studiorum-Universita di Bologna, Dipartimento di Fisica e Astronomia, Bologna (Italy)

    2017-08-15

    The Cryogenic Underground Observatory for Rare Events (CUORE) is designed to search for neutrinoless double beta decay of {sup 130}Te with an array of 988 TeO{sub 2} bolometers operating at temperatures around 10 mK. The experiment is currently being commissioned in Hall A of Laboratori Nazionali del Gran Sasso, Italy. The goal of CUORE is to reach a 90% C.L. exclusion sensitivity on the {sup 130}Te decay half-life of 9 x 10{sup 25} years after 5 years of data taking. The main issue to be addressed to accomplish this aim is the rate of background events in the region of interest, which must not be higher than 10{sup -2} counts/keV/kg/year. We developed a detailed Monte Carlo simulation, based on results from a campaign of material screening, radioassays, and bolometric measurements, to evaluate the expected background. This was used over the years to guide the construction strategies of the experiment and we use it here to project a background model for CUORE. In this paper we report the results of our study and our expectations for the background rate in the energy region where the peak signature of neutrinoless double beta decay of {sup 130}Te is expected. (orig.)

  12. The projected background for the CUORE experiment

    Science.gov (United States)

    Alduino, C.; Alfonso, K.; Artusa, D. R.; Avignone, F. T.; Azzolini, O.; Banks, T. I.; Bari, G.; Beeman, J. W.; Bellini, F.; Benato, G.; Bersani, A.; Biassoni, M.; Branca, A.; Brofferio, C.; Bucci, C.; Camacho, A.; Caminata, A.; Canonica, L.; Cao, X. G.; Capelli, S.; Cappelli, L.; Carbone, L.; Cardani, L.; Carniti, P.; Casali, N.; Cassina, L.; Chiesa, D.; Chott, N.; Clemenza, M.; Copello, S.; Cosmelli, C.; Cremonesi, O.; Creswick, R. J.; Cushman, J. S.; D'Addabbo, A.; Dafinei, I.; Davis, C. J.; Dell'Oro, S.; Deninno, M. M.; Di Domizio, S.; Di Vacri, M. L.; Drobizhev, A.; Fang, D. Q.; Faverzani, M.; Fernandes, G.; Ferri, E.; Ferroni, F.; Fiorini, E.; Franceschi, M. A.; Freedman, S. J.; Fujikawa, B. K.; Giachero, A.; Gironi, L.; Giuliani, A.; Gladstone, L.; Gorla, P.; Gotti, C.; Gutierrez, T. D.; Haller, E. E.; Han, K.; Hansen, E.; Heeger, K. M.; Hennings-Yeomans, R.; Hickerson, K. P.; Huang, H. Z.; Kadel, R.; Keppel, G.; Kolomensky, Yu. G.; Leder, A.; Ligi, C.; Lim, K. E.; Ma, Y. G.; Maino, M.; Marini, L.; Martinez, M.; Maruyama, R. H.; Mei, Y.; Moggi, N.; Morganti, S.; Mosteiro, P. J.; Napolitano, T.; Nastasi, M.; Nones, C.; Norman, E. B.; Novati, V.; Nucciotti, A.; O'Donnell, T.; Ouellet, J. L.; Pagliarone, C. E.; Pallavicini, M.; Palmieri, V.; Pattavina, L.; Pavan, M.; Pessina, G.; Pettinacci, V.; Piperno, G.; Pira, C.; Pirro, S.; Pozzi, S.; Previtali, E.; Rosenfeld, C.; Rusconi, C.; Sakai, M.; Sangiorgio, S.; Santone, D.; Schmidt, B.; Schmidt, J.; Scielzo, N. D.; Singh, V.; Sisti, M.; Smith, A. R.; Taffarello, L.; Tenconi, M.; Terranova, F.; Tomei, C.; Trentalange, S.; Vignati, M.; Wagaarachchi, S. L.; Wang, B. S.; Wang, H. W.; Welliver, B.; Wilson, J.; Winslow, L. A.; Wise, T.; Woodcraft, A.; Zanotti, L.; Zhang, G. Q.; Zhu, B. X.; Zimmermann, S.; Zucchelli, S.; Laubenstein, M.

    2017-08-01

    The Cryogenic Underground Observatory for Rare Events (CUORE) is designed to search for neutrinoless double beta decay of ^{130}Te with an array of 988 TeO_2 bolometers operating at temperatures around 10 mK. The experiment is currently being commissioned in Hall A of Laboratori Nazionali del Gran Sasso, Italy. The goal of CUORE is to reach a 90% C.L. exclusion sensitivity on the ^{130}Te decay half-life of 9 × 10^{25} years after 5 years of data taking. The main issue to be addressed to accomplish this aim is the rate of background events in the region of interest, which must not be higher than 10^{-2} counts/keV/kg/year. We developed a detailed Monte Carlo simulation, based on results from a campaign of material screening, radioassays, and bolometric measurements, to evaluate the expected background. This was used over the years to guide the construction strategies of the experiment and we use it here to project a background model for CUORE. In this paper we report the results of our study and our expectations for the background rate in the energy region where the peak signature of neutrinoless double beta decay of ^{130}Te is expected.

  13. The background in the experiment Gerda

    Science.gov (United States)

    Agostini, M.; Allardt, M.; Andreotti, E.; Bakalyarov, A. M.; Balata, M.; Barabanov, I.; Barnabé Heider, M.; Barros, N.; Baudis, L.; Bauer, C.; Becerici-Schmidt, N.; Bellotti, E.; Belogurov, S.; Belyaev, S. T.; Benato, G.; Bettini, A.; Bezrukov, L.; Bode, T.; Brudanin, V.; Brugnera, R.; Budjáš, D.; Caldwell, A.; Cattadori, C.; Chernogorov, A.; Cossavella, F.; Demidova, E. V.; Domula, A.; Egorov, V.; Falkenstein, R.; Ferella, A.; Freund, K.; Frodyma, N.; Gangapshev, A.; Garfagnini, A.; Gotti, C.; Grabmayr, P.; Gurentsov, V.; Gusev, K.; Guthikonda, K. K.; Hampel, W.; Hegai, A.; Heisel, M.; Hemmer, S.; Heusser, G.; Hofmann, W.; Hult, M.; Inzhechik, L. V.; Ioannucci, L.; Csáthy, J. Janicskó; Jochum, J.; Junker, M.; Kihm, T.; Kirpichnikov, I. V.; Kirsch, A.; Klimenko, A.; Knöpfle, K. T.; Kochetov, O.; Kornoukhov, V. N.; Kuzminov, V. V.; Laubenstein, M.; Lazzaro, A.; Lebedev, V. I.; Lehnert, B.; Liao, H. Y.; Lindner, M.; Lippi, I.; Liu, X.; Lubashevskiy, A.; Lubsandorzhiev, B.; Lutter, G.; Macolino, C.; Machado, A. A.; Majorovits, B.; Maneschg, W.; Nemchenok, I.; Nisi, S.; O'Shaughnessy, C.; Palioselitis, D.; Pandola, L.; Pelczar, K.; Pessina, G.; Pullia, A.; Riboldi, S.; Sada, C.; Salathe, M.; Schmitt, C.; Schreiner, J.; Schulz, O.; Schwingenheuer, B.; Schönert, S.; Shevchik, E.; Shirchenko, M.; Simgen, H.; Smolnikov, A.; Stanco, L.; Strecker, H.; Tarka, M.; Ur, C. A.; Vasenko, A. A.; Volynets, O.; von Sturm, K.; Wagner, V.; Walter, M.; Wegmann, A.; Wester, T.; Wojcik, M.; Yanovich, E.; Zavarise, P.; Zhitnikov, I.; Zhukov, S. V.; Zinatulina, D.; Zuber, K.; Zuzel, G.

    2014-04-01

    The GERmanium Detector Array ( Gerda) experiment at the Gran Sasso underground laboratory (LNGS) of INFN is searching for neutrinoless double beta () decay of Ge. The signature of the signal is a monoenergetic peak at 2039 keV, the value of the decay. To avoid bias in the signal search, the present analysis does not consider all those events, that fall in a 40 keV wide region centered around . The main parameters needed for the analysis are described. A background model was developed to describe the observed energy spectrum. The model contains several contributions, that are expected on the basis of material screening or that are established by the observation of characteristic structures in the energy spectrum. The model predicts a flat energy spectrum for the blinding window around with a background index ranging from 17.6 to 23.8 cts/(keV kg yr). A part of the data not considered before has been used to test if the predictions of the background model are consistent. The observed number of events in this energy region is consistent with the background model. The background at is dominated by close sources, mainly due to K, Bi, Th, Co and emitting isotopes from the Ra decay chain. The individual fractions depend on the assumed locations of the contaminants. It is shown, that after removal of the known peaks, the energy spectrum can be fitted in an energy range of 200 keV around with a constant background. This gives a background index consistent with the full model and uncertainties of the same size.

  14. Background reduction in the SNO+ experiment

    Energy Technology Data Exchange (ETDEWEB)

    Segui, L. [University of Oxford, Denys Wilkinson Building, Keble Road, OX1 Oxford (United Kingdom)

    2015-08-17

    SNO+ is a large multi-purpose liquid scintillator experiment, which first aim is to detect the neutrinoless double beta decay of {sup 130}Te. It is placed at SNOLAB, at 6000 m.w.e. and it is based on the SNO infrastructure. SNO+ will contain approximately 780 tonnes of liquid scintillator, loaded with {sup 130}Te inside an acrylic vessel (AV) with an external volume of ultra pure water to reduce the external backgrounds. Light produced in the scintillator by the interaction of particles will be detected with about 9,000 photomultiplier’s. For the neutrinoless double beta decay phase, due to its the extremely low rate expected, the control, knowledge and reduction of the background is essential. Moreover, it will also benefit other phases of the experiment focused on the study of solar neutrinos, nucleon decay, geoneutrinos and supernovae. In order to reduce the internal background level, a novel purification technique for tellurium loaded scintillators has been developed by the collaboration that reduces the U/Th concentration and several cosmic-activated isotopes by at least a factor 10{sup 2} -10{sup 3} in a single pass. In addition, different rejection techniques have been developed for the remaining internal backgrounds based on Monte-Carlo simulations. In this work, the scintillator purification technique and the levels obtained with it will be discussed. Furthermore, an overview of the different backgrounds for the double-beta phase will be presented, highlighting some of the techniques developed to reject the remained decays based on their expected timing differences.

  15. A background free double beta decay experiment

    International Nuclear Information System (INIS)

    Giomataris, I

    2011-01-01

    We present a new detection scheme for rejecting backgrounds in neutrino-less double beta decay experiments. It relies on the detection of Cherenkov light emitted by electrons in the MeV region. The momentum threshold is tuned to reach a good discrimination between background and good events. We consider many detector concepts and a range of target materials. The most promising is the high-pressure 136 Xe emitter where the required energy threshold is easily adjusted. Combination of this concept and a high pressure Time Projection Chamber could provide an optimal solution. A simple and low cost effective solution is the use of the Spherical Proportional Counter that provides, using a single read-out channel, two delayed signals from ionization and Cherenkov light. In solid-state double beta decay emitters, because of its higher density, the considered process is out of energy range. An escape will be the fabrication of double decay emitters having lower density by using for instance the aerogel technique. It is surprising that a technology used for particle identification in high-energy physics becomes a powerful tool for rejecting backgrounds in such low-energy experiments.

  16. Fourier transform infrared spectrometery: an undergraduate experiment

    International Nuclear Information System (INIS)

    Lerner, L

    2016-01-01

    Simple apparatus is developed, providing undergraduate students with a solid understanding of Fourier transform (FT) infrared (IR) spectroscopy in a hands on experiment. Apart from its application to measuring the mid-IR spectra of organic molecules, the experiment introduces several techniques with wide applicability in physics, including interferometry, the FT, digital data analysis, and control theory. (paper)

  17. Calculation of neutron background for underground experiments

    Energy Technology Data Exchange (ETDEWEB)

    Tomasello, V. [Department of Physics and Astronomy, University of Sheffield, Hounsfield Road, Sheffield S3 7RH (United Kingdom); Physikalisches Institut, Eberhard Karls Universitaet Tuebingen, Auf der Morgenstelle 14, Tuebingen D-72076 (Germany)], E-mail: v.tomasello@sheffield.ac.uk; Kudryavtsev, V.A.; Robinson, M. [Department of Physics and Astronomy, University of Sheffield, Hounsfield Road, Sheffield S3 7RH (United Kingdom)

    2008-10-01

    New generation dark matter experiments aim at exploring the 10{sup -9}-10{sup -10}pb cross-section region for the WIMP-nucleon scalar interactions. Neutrons produced in the detector components are one of the main factors that can limit detector sensitivity. Estimation of the background from this source then becomes a crucial task for designing future large-scale detectors. Energy spectra and production rates for neutrons coming from radioactive contamination are required for all materials in and around the detector. In order to estimate neutron yields and spectra, the cross-sections of ({alpha},n) reactions and probabilities of transitions to different excited states should be known. Cross-sections and transition probabilities have been calculated using EMPIRE2.19 for several isotopes, and for some isotopes, a comparison with the experimental data is shown. The results have been used to calculate the neutron spectra from materials using the code SOURCES4A. Neutron background event rates from some detector components in a hypothetical dark matter detector based on Ge crystals have been estimated. Some requirements for the radiopurity of the materials have been deduced from the results of these simulations.

  18. Calculation of neutron background for underground experiments

    International Nuclear Information System (INIS)

    Tomasello, V.; Kudryavtsev, V.A.; Robinson, M.

    2008-01-01

    New generation dark matter experiments aim at exploring the 10 -9 -10 -10 pb cross-section region for the WIMP-nucleon scalar interactions. Neutrons produced in the detector components are one of the main factors that can limit detector sensitivity. Estimation of the background from this source then becomes a crucial task for designing future large-scale detectors. Energy spectra and production rates for neutrons coming from radioactive contamination are required for all materials in and around the detector. In order to estimate neutron yields and spectra, the cross-sections of (α,n) reactions and probabilities of transitions to different excited states should be known. Cross-sections and transition probabilities have been calculated using EMPIRE2.19 for several isotopes, and for some isotopes, a comparison with the experimental data is shown. The results have been used to calculate the neutron spectra from materials using the code SOURCES4A. Neutron background event rates from some detector components in a hypothetical dark matter detector based on Ge crystals have been estimated. Some requirements for the radiopurity of the materials have been deduced from the results of these simulations

  19. Infrared radiation scene generation of stars and planets in celestial background

    Science.gov (United States)

    Guo, Feng; Hong, Yaohui; Xu, Xiaojian

    2014-10-01

    An infrared (IR) radiation generation model of stars and planets in celestial background is proposed in this paper. Cohen's spectral template1 is modified for high spectral resolution and accuracy. Based on the improved spectral template for stars and the blackbody assumption for planets, an IR radiation model is developed which is able to generate the celestial IR background for stars and planets appearing in sensor's field of view (FOV) for specified observing date and time, location, viewpoint and spectral band over 1.2μm ~ 35μm. In the current model, the initial locations of stars are calculated based on midcourse space experiment (MSX) IR astronomical catalogue (MSX-IRAC) 2 , while the initial locations of planets are calculated using secular variations of the planetary orbits (VSOP) theory. Simulation results show that the new IR radiation model has higher resolution and accuracy than common model.

  20. Cosmic Infrared Background Fluctuations in Deep Spitzer Infrared Array Camera Images: Data Processing and Analysis

    Science.gov (United States)

    Arendt, Richard; Kashlinsky, A.; Moseley, S.; Mather, J.

    2010-01-01

    This paper provides a detailed description of the data reduction and analysis procedures that have been employed in our previous studies of spatial fluctuation of the cosmic infrared background (CIB) using deep Spitzer Infrared Array Camera observations. The self-calibration we apply removes a strong instrumental signal from the fluctuations that would otherwise corrupt the results. The procedures and results for masking bright sources and modeling faint sources down to levels set by the instrumental noise are presented. Various tests are performed to demonstrate that the resulting power spectra of these fields are not dominated by instrumental or procedural effects. These tests indicate that the large-scale ([greater, similar]30') fluctuations that remain in the deepest fields are not directly related to the galaxies that are bright enough to be individually detected. We provide the parameterization of these power spectra in terms of separate instrument noise, shot noise, and power-law components. We discuss the relationship between fluctuations measured at different wavelengths and depths, and the relations between constraints on the mean intensity of the CIB and its fluctuation spectrum. Consistent with growing evidence that the [approx]1-5 [mu]m mean intensity of the CIB may not be as far above the integrated emission of resolved galaxies as has been reported in some analyses of DIRBE and IRTS observations, our measurements of spatial fluctuations of the CIB intensity indicate the mean emission from the objects producing the fluctuations is quite low ([greater, similar]1 nW m-2 sr-1 at 3-5 [mu]m), and thus consistent with current [gamma]-ray absorption constraints. The source of the fluctuations may be high-z Population III objects, or a more local component of very low luminosity objects with clustering properties that differ from the resolved galaxies. Finally, we discuss the prospects of the upcoming space-based surveys to directly measure the epochs

  1. COSMIC INFRARED BACKGROUND FLUCTUATIONS IN DEEP SPITZER INFRARED ARRAY CAMERA IMAGES: DATA PROCESSING AND ANALYSIS

    International Nuclear Information System (INIS)

    Arendt, Richard G.; Kashlinsky, A.; Moseley, S. H.; Mather, J.

    2010-01-01

    This paper provides a detailed description of the data reduction and analysis procedures that have been employed in our previous studies of spatial fluctuation of the cosmic infrared background (CIB) using deep Spitzer Infrared Array Camera observations. The self-calibration we apply removes a strong instrumental signal from the fluctuations that would otherwise corrupt the results. The procedures and results for masking bright sources and modeling faint sources down to levels set by the instrumental noise are presented. Various tests are performed to demonstrate that the resulting power spectra of these fields are not dominated by instrumental or procedural effects. These tests indicate that the large-scale (∼>30') fluctuations that remain in the deepest fields are not directly related to the galaxies that are bright enough to be individually detected. We provide the parameterization of these power spectra in terms of separate instrument noise, shot noise, and power-law components. We discuss the relationship between fluctuations measured at different wavelengths and depths, and the relations between constraints on the mean intensity of the CIB and its fluctuation spectrum. Consistent with growing evidence that the ∼1-5 μm mean intensity of the CIB may not be as far above the integrated emission of resolved galaxies as has been reported in some analyses of DIRBE and IRTS observations, our measurements of spatial fluctuations of the CIB intensity indicate the mean emission from the objects producing the fluctuations is quite low (∼>1 nW m -2 sr -1 at 3-5 μm), and thus consistent with current γ-ray absorption constraints. The source of the fluctuations may be high-z Population III objects, or a more local component of very low luminosity objects with clustering properties that differ from the resolved galaxies. Finally, we discuss the prospects of the upcoming space-based surveys to directly measure the epochs inhabited by the populations producing these

  2. A new real time infrared background discrimination radiometer (BDR)

    International Nuclear Information System (INIS)

    Kopolovich, Z.; Cabib, D.; Buckwald, R.A.

    1989-01-01

    This paper reports on a new radiometer (BDR) that has been developed, which discriminates small differences between an object and its surrounding background, and is able to measure an object's changing contrast when the contrast of a moving object is to be measured against a changing background. The difference in radiant emittance of a small object against its background or of two objects with respect to each other and this difference is small compared to the emittance itself. Practical examples of such measurements are contrast measurements of airplanes and missiles in flight, contrast measurements of small, weak objects on a warm background and uniformity measurements of radiant emittance from an object's surface. Previous instruments were unable to make such measurements since the process of contrast measurement with a fixed field of view radiometer is too slow for implementation on flying objects; detection of a small difference between two large DC signals is impossible in a traditional fixed field of view radiometer when the instrument itself is saturated

  3. Background simulation for the COBRA-experiment

    Energy Technology Data Exchange (ETDEWEB)

    Quante, Thomas [TU Dortmund, Institut fuer Physik (Germany); Collaboration: COBRA-Collaboration

    2015-07-01

    COBRA is a next-generation experiment searching for neutrinoless double beta (0νββ) decay using CdZnTe semiconductor detectors. The main focus is on {sup 116}Cd, with a Q-value of 2813.5 keV well above the highest dominant naturally occurring gamma lines. By measuring the half-life of the 0νββ decay, it is possible to clarify the nature of the neutrino as either Dirac or Majorana particle and furthermore to determine the effective Majorana mass. COBRA is currently in the demonstrator phase to study possible background contributions and gain information about the longterm stability of the used detectors. For this purpose a demonstrator array made up of 64 Cadmium-Zinc-Telluride (CdZnTe) semiconductor detectors in coplanar grid configuration was designed and realised at the Gran Sasso Underground laboratory (LNGS) in Italy. Simulations of the whole demonstrator setup are ongoing to reproduce the measured spectra for each detector. This is done in two steps. The first uses the Geant4 based framework VENOM for tracking and energy deposition inside each detector. Detector effects like the energy resolution and electron trapping have to be applied in the second step. The used detector geometry has to be verified against calibration measurements. This talk gives an overview of the current simulation status.

  4. The Bolund Experiment: Overview and Background

    DEFF Research Database (Denmark)

    Bechmann, Andreas; Berg, Jacob; Courtney, Michael

    The Bolund experiment is a measuring campaign performed in 2007 and 2008. The aim of the experiment is to measure the flow field around the Bolund hill in order to provide a dataset for validating numerical flow models. The present report gives an overview of the whole experiment including a desc...

  5. Planck 2013 results. XVIII. The gravitational lensing-infrared background correlation

    DEFF Research Database (Denmark)

    Ade, P. A. R.; Aghanim, N.; Armitage-Caplan, C.

    2013-01-01

    The multi-frequency capability of the Planck satellite provides information both on the integrated history of star formation (via the cosmic infrared background, or CIB) and on the distribution of dark matter (via the lensing effect on the cosmic microwave background, or CMB). The conjunction of ...

  6. A COSMIC MICROWAVE BACKGROUND LENSING MASS MAP AND ITS CORRELATION WITH THE COSMIC INFRARED BACKGROUND

    Energy Technology Data Exchange (ETDEWEB)

    Holder, G. P.; De Haan, T.; Dobbs, M. A.; Dudley, J. [Department of Physics, McGill University, Montreal, Quebec H3A 2T8 (Canada); Viero, M. P.; Bock, J. [California Institute of Technology, Pasadena, CA 91125 (United States); Zahn, O. [Berkeley Center for Cosmological Physics, Department of Physics, University of California, and Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Aird, K. A. [University of Chicago, Chicago, IL 60637 (United States); Benson, B. A.; Bhattacharya, S.; Bleem, L. E.; Carlstrom, J. E.; Chang, C. L.; Crawford, T. M.; Crites, A. T. [Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637 (United States); Brodwin, M. [Department of Physics and Astronomy, University of Missouri, Kansas City, MO 64110 (United States); Cho, H-M. [NIST Quantum Devices Group, Boulder, CO 80305 (United States); Conley, A. [Center for Astrophysics and Space Astronomy, University of Colorado, Boulder, CO 80309 (United States); George, E. M. [Department of Physics, University of California, Berkeley, CA 94720 (United States); Halverson, N. W. [Department of Astrophysical and Planetary Sciences and Department of Physics, University of Colorado, Boulder, CO 80309 (United States); and others

    2013-07-01

    We use a temperature map of the cosmic microwave background (CMB) obtained using the South Pole Telescope at 150 GHz to construct a map of the gravitational convergence to z {approx} 1100, revealing the fluctuations in the projected mass density. This map shows individual features that are significant at the {approx}4{sigma} level, providing the first image of CMB lensing convergence. We cross-correlate this map with Herschel/SPIRE maps covering 90 deg{sup 2} at wavelengths of 500, 350, and 250 {mu}m. We show that these submillimeter (submm) wavelength maps are strongly correlated with the lensing convergence map, with detection significances in each of the three submm bands ranging from 6.7{sigma} to 8.8{sigma}. We fit the measurement of the cross power spectrum assuming a simple constant bias model and infer bias factors of b = 1.3-1.8, with a statistical uncertainty of 15%, depending on the assumed model for the redshift distribution of the dusty galaxies that are contributing to the Herschel/SPIRE maps.

  7. The number counts and infrared backgrounds from infrared-bright galaxies

    International Nuclear Information System (INIS)

    Hacking, P.B.; Soifer, B.T.

    1991-01-01

    Extragalactic number counts and diffuse backgrounds at 25, 60, and 100 microns are predicted using new luminosity functions and improved spectral-energy distribution density functions derived from IRAS observations of nearby galaxies. Galaxies at redshifts z less than 3 that are like those in the local universe should produce a minimum diffuse background of 0.0085, 0.038, and 0.13 MJy/sr at 25, 60, and 100 microns, respectively. Models with significant luminosity evolution predict backgrounds about a factor of 4 greater than this minimum. 22 refs

  8. Planck 2013 results. XXX. Cosmic infrared background measurements and implications for star formation

    DEFF Research Database (Denmark)

    Ade, P. A. R.; Aghanim, N.; Armitage-Caplan, C.

    2014-01-01

    We present new measurements of cosmic infrared background (CIB) anisotropies using Planck. Combining HFI data with IRAS, the angular auto-and cross-frequency power spectrum is measured from 143 to 3000 GHz, and the auto-bispectrum from 217 to 545 GHz. The total areas used to compute the CIB power...

  9. Planck intermediate results: XLVIII. Disentangling Galactic dust emission and cosmic infrared background anisotropies

    DEFF Research Database (Denmark)

    Aghanim, N.; Ashdown, M.; Aumont, J.

    2016-01-01

    Using the Planck 2015 data release (PR2) temperature maps, we separate Galactic thermal dust emission from cosmic infrared background (CIB) anisotropies. For this purpose, we implement a specifically tailored component-separation method, the so-called generalized needlet internal linear combinati...

  10. Infrared Thermography Approach for Effective Shielding Area of Field Smoke Based on Background Subtraction and Transmittance Interpolation.

    Science.gov (United States)

    Tang, Runze; Zhang, Tonglai; Chen, Yongpeng; Liang, Hao; Li, Bingyang; Zhou, Zunning

    2018-05-06

    Effective shielding area is a crucial indicator for the evaluation of the infrared smoke-obscuring effectiveness on the battlefield. The conventional methods for assessing the shielding area of the smoke screen are time-consuming and labor intensive, in addition to lacking precision. Therefore, an efficient and convincing technique for testing the effective shielding area of the smoke screen has great potential benefits in the smoke screen applications in the field trial. In this study, a thermal infrared sensor with a mid-wavelength infrared (MWIR) range of 3 to 5 μm was first used to capture the target scene images through clear as well as obscuring smoke, at regular intervals. The background subtraction in motion detection was then applied to obtain the contour of the smoke cloud at each frame. The smoke transmittance at each pixel within the smoke contour was interpolated based on the data that was collected from the image. Finally, the smoke effective shielding area was calculated, based on the accumulation of the effective shielding pixel points. One advantage of this approach is that it utilizes only one thermal infrared sensor without any other additional equipment in the field trial, which significantly contributes to the efficiency and its convenience. Experiments have been carried out to demonstrate that this approach can determine the effective shielding area of the field infrared smoke both practically and efficiently.

  11. Infrared Thermography Approach for Effective Shielding Area of Field Smoke Based on Background Subtraction and Transmittance Interpolation

    Directory of Open Access Journals (Sweden)

    Runze Tang

    2018-05-01

    Full Text Available Effective shielding area is a crucial indicator for the evaluation of the infrared smoke-obscuring effectiveness on the battlefield. The conventional methods for assessing the shielding area of the smoke screen are time-consuming and labor intensive, in addition to lacking precision. Therefore, an efficient and convincing technique for testing the effective shielding area of the smoke screen has great potential benefits in the smoke screen applications in the field trial. In this study, a thermal infrared sensor with a mid-wavelength infrared (MWIR range of 3 to 5 μm was first used to capture the target scene images through clear as well as obscuring smoke, at regular intervals. The background subtraction in motion detection was then applied to obtain the contour of the smoke cloud at each frame. The smoke transmittance at each pixel within the smoke contour was interpolated based on the data that was collected from the image. Finally, the smoke effective shielding area was calculated, based on the accumulation of the effective shielding pixel points. One advantage of this approach is that it utilizes only one thermal infrared sensor without any other additional equipment in the field trial, which significantly contributes to the efficiency and its convenience. Experiments have been carried out to demonstrate that this approach can determine the effective shielding area of the field infrared smoke both practically and efficiently.

  12. Planck 2015 results: XXIII. The thermal Sunyaev-Zeldovich effect-cosmic infrared background correlation

    DEFF Research Database (Denmark)

    Ade, P. A R; Aghanim, N.; Arnaud, M.

    2016-01-01

    We use Planck data to detect the cross-correlation between the thermal Sunyaev-Zeldovich (tSZ) effect and the infrared emission from the galaxies that make up the the cosmic infrared background (CIB). We first perform a stacking analysis towards Planck-confirmed galaxy clusters. We detect infrared...... that infrared galaxies in the outskirts of clusters have higher infrared flux than cluster-core galaxies. We also study the cross-correlation between tSZ and CIB anisotropies, following three alternative approaches based on power spectrum analyses: (i) using a catalogue of confirmed clusters detected in Planck...... data; (ii) using an all-sky tSZ map built from Planck frequency maps; and (iii) using cross-spectra between Planck frequency maps. With the three different methods, we detect the tSZ-CIB cross-power spectrum at significance levels of (i) 6σ; (ii) 3σ; and (iii) 4σ. We model the tSZ-CIB cross-correlation...

  13. Planck early results. XVIII. The power spectrum of cosmic infrared background anisotropies

    DEFF Research Database (Denmark)

    Poutanen, T.; Natoli, P.; Polenta, G.

    2011-01-01

    Using Planck maps of six regions of low Galactic dust emission with a total area of about 140 deg2, we determine the angular power spectra of cosmic infrared background (CIB) anisotropies from multipole = 200 to = 2000 at 217, 353, 545 and 857 GHz. We use 21-cm observations of Hi as a tracer...... of thermal dust emission to reduce the already low level of Galactic dust emission and use the 143 GHz Planck maps in these fields to clean out cosmic microwave background anisotropies. Both of these cleaning processes are necessary to avoid significant contamination of the CIB signal. We measure correlated...

  14. Neutron- and muon-induced background in underground physics experiments

    International Nuclear Information System (INIS)

    Kudryavtsev, V.A.; Tomasello, V.; Pandola, L.

    2008-01-01

    Background induced by neutrons in deep underground laboratories is a critical issue for all experiments looking for rare events, such as dark matter interactions or neutrinoless ββ decay. Neutrons can be produced either by natural radioactivity, via spontaneous fission or (α, n) reactions, or by interactions initiated by high-energy cosmic rays. In all underground experiments, Monte Carlo simulations of neutron background play a crucial role for the evaluation of the total background rate and for the optimization of rejection strategies. The Monte Carlo methods that are commonly employed to evaluate neutron-induced background and to optimize the experimental setup, are reviewed and discussed. Focus is given to the issue of reliability of Monte Carlo background estimates. (orig.)

  15. Neutron- and muon-induced background in underground physics experiments

    Energy Technology Data Exchange (ETDEWEB)

    Kudryavtsev, V.A.; Tomasello, V. [University of Sheffield, Department of Physics and Astronomy, Sheffield (United Kingdom); Pandola, L. [Laboratori Nazionali del Gran Sasso, INFN, Assergi (Italy)

    2008-05-15

    Background induced by neutrons in deep underground laboratories is a critical issue for all experiments looking for rare events, such as dark matter interactions or neutrinoless {beta}{beta} decay. Neutrons can be produced either by natural radioactivity, via spontaneous fission or ({alpha}, n) reactions, or by interactions initiated by high-energy cosmic rays. In all underground experiments, Monte Carlo simulations of neutron background play a crucial role for the evaluation of the total background rate and for the optimization of rejection strategies. The Monte Carlo methods that are commonly employed to evaluate neutron-induced background and to optimize the experimental setup, are reviewed and discussed. Focus is given to the issue of reliability of Monte Carlo background estimates. (orig.)

  16. Evaluation Of Spatial Filters For Background Suppression In Infrared Mosaic Sensor Systems

    Science.gov (United States)

    Bergen, T. L.; Mazaika, P. K.

    1982-12-01

    Spaceborne infrared mosaic sensors have been proposed for future surveillance systems. Because these systems will generate a large volume of data, background suppression will require algorithms which use innovative architectures and minimal storage. This paper analyzes the implementation and performance of candidate temporal and spatial filters. Spatial filters are attractive because they require far less memory, can effectively exploit a parallel, pipelined architecture, and are relatively insensitive to target speed. However, the performance of spatial filtering is substantially worse than that of temporal filtering when the sensor has good line-of-sight stability.

  17. Muon-induced backgrounds in the CUORICINO experiment

    Energy Technology Data Exchange (ETDEWEB)

    Andreotti, E.; Arnaboldi, C.; Avignone III, F. T.; Balata, M.; Bandac, I.; Barucci, M.; Beeman, J. W.; Bellini, F.; Bloxham, T.; Brofferio, C.; Bryant, A.; Bucci, C.; Canonica, L.; Capelli, S.; Carbone, L.; Carrettoni, M.; Clemenza, M.; Cremonesi, O.; Creswick, R. J.; Domizio, S. Di; Dolinski, M. J.; Ejzak, L.; Faccini, R.; Farach, H. A.; Ferri, E.; Ferroni, F.; Fiorini, E.; Foggetta, L.; Giachero, A.; Gironi, L.; Giuliani, A.; Gorla, P.; Guardincerri, E.; Gutierrez, T. D.; Haller, E. E.; Kadel, R.; Kazkaz, K.; Kraft, S.; Kogler, L.; Kolomensky, Yu. G.; Maiano, C.; Maruyama, R. H.; Martinez, C.; Martinez, M.; Mizouni, L.; Morganti, S.; Nisi, S.; Nones, C.; Norman, E. B.; Nucciotti, A.; Orio, F.; Pallavicini, M.; Palmieri, V.; Pattavina, L.; Pavan, M.; Pedretti, M.; Pessina, G.; Pirro, S.; Previtali, E.; Risegari, L.; Rosenfeld, C.; Rusconi, C.; Salvioni, C.; Sangiorgio, S.; Schaeffer, D.; Scielzo, N. D.; Sisti, M.; Smith, A. R.; Tomei, C.; Ventura, G.; Vignati, M.

    2010-04-15

    To better understand the contribution of cosmic ray muons to the CUORICINO background, ten plastic scintillator detectors were installed at the CUORICINO siteand operated during the final 3 months of the experiment. From these measurements, an upper limit of 0.0021 counts/(keV.kg.yr) (95percent c.l.) was obtained on the cosmicray induced background in the neutrinoless double beta decay region of interest. The measurements were also compared to Geant4 simulations.

  18. Interpreting the cosmic far-infrared background anisotropies using a gas regulator model

    Science.gov (United States)

    Wu, Hao-Yi; Doré, Olivier; Teyssier, Romain; Serra, Paolo

    2018-04-01

    Cosmic far-infrared background (CFIRB) is a powerful probe of the history of star formation rate (SFR) and the connection between baryons and dark matter across cosmic time. In this work, we explore to which extent the CFIRB anisotropies can be reproduced by a simple physical framework for galaxy evolution, the gas regulator (bathtub) model. This model is based on continuity equations for gas, stars, and metals, taking into account cosmic gas accretion, star formation, and gas ejection. We model the large-scale galaxy bias and small-scale shot noise self-consistently, and we constrain our model using the CFIRB power spectra measured by Planck. Because of the simplicity of the physical model, the goodness of fit is limited. We compare our model predictions with the observed correlation between CFIRB and gravitational lensing, bolometric infrared luminosity functions, and submillimetre source counts. The strong clustering of CFIRB indicates a large galaxy bias, which corresponds to haloes of mass 1012.5 M⊙ at z = 2, higher than the mass associated with the peak of the star formation efficiency. We also find that the far-infrared luminosities of haloes above 1012 M⊙ are higher than the expectation from the SFR observed in ultraviolet and optical surveys.

  19. The study of infrared target recognition at sea background based on visual attention computational model

    Science.gov (United States)

    Wang, Deng-wei; Zhang, Tian-xu; Shi, Wen-jun; Wei, Long-sheng; Wang, Xiao-ping; Ao, Guo-qing

    2009-07-01

    Infrared images at sea background are notorious for the low signal-to-noise ratio, therefore, the target recognition of infrared image through traditional methods is very difficult. In this paper, we present a novel target recognition method based on the integration of visual attention computational model and conventional approach (selective filtering and segmentation). The two distinct techniques for image processing are combined in a manner to utilize the strengths of both. The visual attention algorithm searches the salient regions automatically, and represented them by a set of winner points, at the same time, demonstrated the salient regions in terms of circles centered at these winner points. This provides a priori knowledge for the filtering and segmentation process. Based on the winner point, we construct a rectangular region to facilitate the filtering and segmentation, then the labeling operation will be added selectively by requirement. Making use of the labeled information, from the final segmentation result we obtain the positional information of the interested region, label the centroid on the corresponding original image, and finish the localization for the target. The cost time does not depend on the size of the image but the salient regions, therefore the consumed time is greatly reduced. The method is used in the recognition of several kinds of real infrared images, and the experimental results reveal the effectiveness of the algorithm presented in this paper.

  20. Reference analysis of the signal + background model in counting experiments

    Science.gov (United States)

    Casadei, D.

    2012-01-01

    The model representing two independent Poisson processes, labelled as ``signal'' and ``background'' and both contributing additively to the total number of counted events, is considered from a Bayesian point of view. This is a widely used model for the searches of rare or exotic events in presence of a background source, as for example in the searches performed by high-energy physics experiments. In the assumption of prior knowledge about the background yield, a reference prior is obtained for the signal alone and its properties are studied. Finally, the properties of the full solution, the marginal reference posterior, are illustrated with few examples.

  1. Muon-induced backgrounds in the CUORICINO experiment

    Energy Technology Data Exchange (ETDEWEB)

    Andreotti, E; Arnaboldi, C; Avignone, F T; Balata, M; Bandac, I; Barucci, M; Beeman, J W; Bellini, F; Bloxham, T; Brofferio, C; Bryant, A; Bucci, C; Canonica, L; Capelli, S; Carbone, L; Carrettoni, M; Clemenza, M; Cremonesi, O; Creswick, R J; Domizio, S D; Dolinski, M J; Ejzak, L; Faccini, R; Farach, H A; Ferri, E; Ferroni, F; Firoini, E; Foggetta, L; Giachero, A; Gironi, L; Giuliani, A; Gorla, P; Guardincerri, E; Gutierrez, T D; Haller, E E; Kadel, R; Kazkaz, K; Kraft, S; Kogler, L; Kolomensky, Y G; Maiano, C; Maruyama, R H; Martinez, C; Martinez, M; Mizouni, L; Morganti, S; Nisi, S; Nones, C; Norman, E B; Nucciotti, A; Orio, F; Pallavicini, M; Palmieri, V; Pattavina, L; Pavan, M; Pedretti, M; Pessina, G; Pirro, S; Previtali, E; Risegari, L; Rosenfeld, C; Rusconi, C; Salvioni, C; Sangiorgio, S; Schaeffer, D; Scielzo, N D; Sisti, M; Smith, A R; Tomei, C; Ventura, G; Vignati, M

    2009-11-16

    To better understand the contribution of cosmic ray muons to the CUORICINO background, ten plastic scintillator detectors were installed at the CUORICINO site and operated during 3 months of the CUORICINO experiment. From these measurements, an upper limit of 0.0021 counts/keV {center_dot} kg {center_dot} yr (95% C.L.) was obtained on the cosmic ray induced background in the neutrinoless double beta decay region of interest. The measurements were compared to Geant4 simulations, which are similar to those that will be used to estimate the backgrounds in CUORE.

  2. THE NEAR-INFRARED BACKGROUND INTENSITY AND ANISOTROPIES DURING THE EPOCH OF REIONIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Cooray, Asantha; Gong Yan; Smidt, Joseph [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Santos, Mario G. [CENTRA, Instituto Superior Tecnico, Technical University of Lisbon, Lisboa 1049-001 (Portugal)

    2012-09-01

    A fraction of the extragalactic near-infrared (near-IR) background light involves redshifted photons from the ultraviolet (UV) emission from galaxies present during reionization at redshifts above 6. The absolute intensity and the anisotropies of the near-IR background provide an observational probe of the first-light galaxies and their spatial distribution. We estimate the extragalactic background light intensity during reionization by accounting for the stellar and nebular emission from first-light galaxies. We require the UV photon density from these galaxies to generate a reionization history that is consistent with the optical depth to electron scattering from cosmic microwave background measurements. We also require the bright-end luminosity function (LF) of galaxies in our models to reproduce the measured Lyman-dropout LFs at redshifts of 6-8. The absolute intensity is about 0.1-0.4 nW m{sup -2} sr{sup -1} at the peak of its spectrum at {approx}1.1 {mu}m. We also discuss the anisotropy power spectrum of the near-IR background using a halo model to describe the galaxy distribution. We compare our predictions for the anisotropy power spectrum to existing measurements from deep near-IR imaging data from Spitzer/IRAC, Hubble/NICMOS, and AKARI. The predicted rms fluctuations at tens of arcminute angular scales are roughly an order of magnitude smaller than the existing measurements. While strong arguments have been made that the measured fluctuations do not have an origin involving faint low-redshift galaxies, we find that measurements in the literature are also incompatible with galaxies present during the era of reionization. The measured near-IR background anisotropies remain unexplained with an unknown origin.

  3. Background studies for the MINER Coherent Neutrino Scattering reactor experiment

    International Nuclear Information System (INIS)

    Agnolet, G.; Baker, W.; Barker, D.; Beck, R.; Carroll, T.J.; Cesar, J.; Cushman, P.; Dent, J.B.; De Rijck, S.; Dutta, B.; Flanagan, W.; Fritts, M.; Gao, Y.; Harris, H.R.; Hays, C.C.; Iyer, V.

    2017-01-01

    The proposed Mitchell Institute Neutrino Experiment at Reactor (MINER) experiment at the Nuclear Science Center at Texas A&M University will search for coherent elastic neutrino-nucleus scattering within close proximity (about 2 m) of a 1 MW TRIGA nuclear reactor core using low threshold, cryogenic germanium and silicon detectors. Given the Standard Model cross section of the scattering process and the proposed experimental proximity to the reactor, as many as 5–20 events/kg/day are expected. We discuss the status of preliminary measurements to characterize the main backgrounds for the proposed experiment. Both in situ measurements at the experimental site and simulations using the MCNP and GEANT4 codes are described. A strategy for monitoring backgrounds during data taking is briefly discussed.

  4. Background studies for the MINER Coherent Neutrino Scattering reactor experiment

    Energy Technology Data Exchange (ETDEWEB)

    Agnolet, G.; Baker, W. [Department of Physics and Astronomy, and the Mitchell Institute for Fundamental Physics and Astronomy, Texas A& M University, College Station, TX 77843 (United States); Barker, D. [School of Physics & Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); Beck, R. [Department of Physics and Astronomy, and the Mitchell Institute for Fundamental Physics and Astronomy, Texas A& M University, College Station, TX 77843 (United States); Carroll, T.J.; Cesar, J. [Department of Physics, University of Texas at Austin, Austin, TX 78712 (United States); Cushman, P. [School of Physics & Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); Dent, J.B. [Department of Physics, University of Louisiana at Lafayette, Lafayette, LA 70504 (United States); De Rijck, S. [Department of Physics, University of Texas at Austin, Austin, TX 78712 (United States); Dutta, B. [Department of Physics and Astronomy, and the Mitchell Institute for Fundamental Physics and Astronomy, Texas A& M University, College Station, TX 77843 (United States); Flanagan, W. [Department of Physics, University of Texas at Austin, Austin, TX 78712 (United States); Fritts, M. [School of Physics & Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); Gao, Y. [Department of Physics and Astronomy, and the Mitchell Institute for Fundamental Physics and Astronomy, Texas A& M University, College Station, TX 77843 (United States); Department of Physics & Astronomy, Wayne State University, Detroit 48201 (United States); Harris, H.R.; Hays, C.C. [Department of Physics and Astronomy, and the Mitchell Institute for Fundamental Physics and Astronomy, Texas A& M University, College Station, TX 77843 (United States); Iyer, V. [School of Physical Sciences, National Institute of Science Education and Research, Jatni - 752050 (India); and others

    2017-05-01

    The proposed Mitchell Institute Neutrino Experiment at Reactor (MINER) experiment at the Nuclear Science Center at Texas A&M University will search for coherent elastic neutrino-nucleus scattering within close proximity (about 2 m) of a 1 MW TRIGA nuclear reactor core using low threshold, cryogenic germanium and silicon detectors. Given the Standard Model cross section of the scattering process and the proposed experimental proximity to the reactor, as many as 5–20 events/kg/day are expected. We discuss the status of preliminary measurements to characterize the main backgrounds for the proposed experiment. Both in situ measurements at the experimental site and simulations using the MCNP and GEANT4 codes are described. A strategy for monitoring backgrounds during data taking is briefly discussed.

  5. Benchmarking the Particle Background in the LHC Experiments

    CERN Document Server

    Gschwendtner, E

    2000-01-01

    The experiments for the Large Hadron Collider LHC at CERN have to work for 15 years in the presence of a very high particle background of photons in the energy range from 100\\,keV to 10\\,MeV and neutrons in the range from thermal energies ($\\approx 0.025\\,$eV) to 20\\,MeV. \\\\ The background is so high that it becomes a major design criterion for the ATLAS ex\\-peri\\-ment, a general purpose experiment at LHC that will be operational in the year 2005. The exact level of this background is poorly known. At present an uncertainty factor of five has to be assumed to which the limited knowledge of the shower processes in the absorber material and the ensueing neutron and photon production is estimated to contribute with a factor 2.5. \\\\ So far, the background has been assessed only through extensive Monte Carlo evaluation with the particle transport code FLUKA. The lack of relevant measurements, which were not done up to now, are to a large extent responsible for this uncertainty. Hence it is essential to benchmark t...

  6. Shielding of the GERDA experiment against external gamma background

    International Nuclear Information System (INIS)

    Barabanov, I.; Bezrukov, L.; Demidova, E.; Gurentsov, V.; Kianovsky, S.; Knoepfle, K.T.; Kornouhkov, V.; Schwingenheuer, B.; Vasenko, A.

    2009-01-01

    The GERmanium Detector Array (GERDA) experiment will search for neutrinoless double beta decay of 76 Ge and is currently under construction at the INFN Laboratori Nazionali del Gran Sasso (LNGS) in Italy. The basic design of GERDA is the use of cryogenic liquid and water of high purity as a superior shield against the hitherto dominant background from external gamma radiation. In this paper we show by Monte Carlo simulations and analytical calculations how GERDA was designed to suppress this background at Q ββ ( 76 Ge)=2039keV to a level of about 10 -4 cts/(keVkgy).

  7. Research on the algorithm of infrared target detection based on the frame difference and background subtraction method

    Science.gov (United States)

    Liu, Yun; Zhao, Yuejin; Liu, Ming; Dong, Liquan; Hui, Mei; Liu, Xiaohua; Wu, Yijian

    2015-09-01

    As an important branch of infrared imaging technology, infrared target tracking and detection has a very important scientific value and a wide range of applications in both military and civilian areas. For the infrared image which is characterized by low SNR and serious disturbance of background noise, an innovative and effective target detection algorithm is proposed in this paper, according to the correlation of moving target frame-to-frame and the irrelevance of noise in sequential images based on OpenCV. Firstly, since the temporal differencing and background subtraction are very complementary, we use a combined detection method of frame difference and background subtraction which is based on adaptive background updating. Results indicate that it is simple and can extract the foreground moving target from the video sequence stably. For the background updating mechanism continuously updating each pixel, we can detect the infrared moving target more accurately. It paves the way for eventually realizing real-time infrared target detection and tracking, when transplanting the algorithms on OpenCV to the DSP platform. Afterwards, we use the optimal thresholding arithmetic to segment image. It transforms the gray images to black-white images in order to provide a better condition for the image sequences detection. Finally, according to the relevance of moving objects between different frames and mathematical morphology processing, we can eliminate noise, decrease the area, and smooth region boundaries. Experimental results proves that our algorithm precisely achieve the purpose of rapid detection of small infrared target.

  8. Cosmic microwave and infrared backgrounds cross-correlation for ISW detection

    International Nuclear Information System (INIS)

    Ilić, S

    2014-01-01

    We have investigated the cross-correlation between the cosmic infrared and microwave backgrounds (CIB and CMB) anisotropies through the integrated Sachs-Wolfe effect. We have first described the CIB anisotropies using a linearly biased power spectrum, then derive the theoretical angular power spectrum of the CMB-CIB cross-correlation for different instruments and frequencies. We have discussed the detectability of the ISW signal by performing a signal-to-noise (SNR) analysis with our predicted spectra. The significances obtained range from 6σ to 7σ in an ideal case, depending on the frequency; in realistic cases which account for the presence of noise including astrophysical contaminants, the results span the range 2 – 5σ, depending strongly on the major contribution to the noise term

  9. Benchmarking the Particle Background in the Large Hadron Collider Experiments

    CERN Document Server

    Gschwendtner, Edda; Fabjan, Christian Wolfgang; Hessey, N P; Otto, Thomas

    2002-01-01

    Background benchmarking measurements have been made to check the low-energy processes which will contribute via nuclear reactions to the radiation background in the LHC experiments at CERN. Previously these processes were only evaluated with Monte Carlo simulations, estimated to be reliable within an uncertainty factor of 2.5. Measurements were carried out in an experimental set-up comparable to the shielding of ATLAS, one of the general-purpose experiments at LHC. The absolute yield and spectral measurements of photons and neutrons emanating from the final stages of the hadronic showers were made with a Bi_4Ge_3O_{12} (BGO) detector. The particle transport code FLUKA was used for detailed simulations. Comparison between measurements and simulations show that they agree within 20% and hence the uncertainty factor resulting from the shower processes can be reduced to a factor of 1.2.

  10. Analysis of auroral infrared emissions observed during the ELIAS experiment

    Directory of Open Access Journals (Sweden)

    G. E. Caledonia

    Full Text Available The ELIAS (Earth Limb Infrared Atmospheric Structure experiment was flown from the Poker Flat Research Range, Alaska in 1983 and successfully monitored visible and infrared emissions from an IBC III+ aurora. Measurements were performed in both staring and scanning modes over several hundred seconds. The data for short- and mid-wave infrared regions have been analyzed in terms of auroral excitation of the NO and NO+ vibrational bands. Auroral excitation efficiencies and kinetic implications are presented.

  11. H-ATLAS: THE COSMIC ABUNDANCE OF DUST FROM THE FAR-INFRARED BACKGROUND POWER SPECTRUM

    Energy Technology Data Exchange (ETDEWEB)

    Thacker, Cameron; Cooray, Asantha; Smidt, Joseph; De Bernardis, Francesco; Mitchell-Wynne, K. [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Amblard, A. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Auld, R.; Eales, S.; Pascale, E. [School of Physics and Astronomy, Cardiff University, The Parade, Cardiff, CF24 3AA (United Kingdom); Baes, M.; Michalowski, M. J. [Sterrenkundig Observatorium, Universiteit Gent, KrijgslAAn 281 S9, B-9000 Gent (Belgium); Clements, D. L.; Dariush, A.; Hopwood, R. [Physics Department, Imperial College London, South Kensington campus, London, SW7 2AZ (United Kingdom); De Zotti, G. [INAF, Osservatorio Astronomico di Padova, Vicolo Osservatorio 5, I-35122 Padova (Italy); Dunne, L.; Maddox, S. [Department of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch (New Zealand); Hoyos, C. [School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, NG7 2RD (United Kingdom); Ibar, E. [UK Astronomy Technology Centre, The Royal Observatory, Blackford Hill, Edinburgh, EH9 3HJ (United Kingdom); Jarvis, M. [Astrophysics, Department of Physics, Keble Road, Oxford, OX1 3RH (United Kingdom); and others

    2013-05-01

    We present a measurement of the angular power spectrum of the cosmic far-infrared background (CFIRB) anisotropies in one of the extragalactic fields of the Herschel Astrophysical Terahertz Large Area Survey at 250, 350, and 500 {mu}m bands. Consistent with recent measurements of the CFIRB power spectrum in Herschel-SPIRE maps, we confirm the existence of a clear one-halo term of galaxy clustering on arcminute angular scales with large-scale two-halo term of clustering at 30 arcmin to angular scales of a few degrees. The power spectrum at the largest angular scales, especially at 250 {mu}m, is contaminated by the Galactic cirrus. The angular power spectrum is modeled using a conditional luminosity function approach to describe the spatial distribution of unresolved galaxies that make up the bulk of the CFIRB. Integrating over the dusty galaxy population responsible for the background anisotropies, we find that the cosmic abundance of dust, relative to the critical density, to be between {Omega}{sub dust} = 10{sup -6} and 8 Multiplication-Sign 10{sup -6} in the redshift range z {approx} 0-3. This dust abundance is consistent with estimates of the dust content in the universe using quasar reddening and magnification measurements in the Sloan Digital Sky Survey.

  12. CROSS-CORRELATION BETWEEN X-RAY AND OPTICAL/NEAR-INFRARED BACKGROUND INTENSITY FLUCTUATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell-Wynne, Ketron; Cooray, Asantha [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Xue, Yongquan [CAS Key Laboratory for Researches in Galaxies and Cosmology, Center for Astrophysics, Department of Astronomy, University of Science and Technology of China, Chinese Academy of Sciences, Hefei, Anhui 230026 (China); Luo, Bin [School of Astronomy and Space Science, Nanjing University, Nanjing, 210093 (China); Brandt, William [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA, 16802 (United States); Koekemoer, Anton [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

    2016-12-01

    Angular power spectra of optical and infrared background anisotropies at wavelengths between 0.5 and 5 μ m are a useful probe of faint sources present during reionization, in addition to faint galaxies and diffuse signals at low redshift. The cross-correlation of these fluctuations with backgrounds at other wavelengths can be used to separate some of these signals. A previous study on the cross-correlation between X-ray and Spitzer fluctuations at 3.6 μ m and 4.5 μ m has been interpreted as evidence for direct collapse black holes present at z  > 12. Here we return to this cross-correlation and study its wavelength dependence from 0.5 to 4.5 μ m using Hubble and Spitzer data in combination with a subset of the 4 Ms Chandra observations in GOODS-S/ECDFS. Our study involves five Hubble bands at 0.6, 0.7, 0.85, 1.25, and 1.6 μ m, and two Spitzer -IRAC bands at 3.6 μ m and 4.5 μ m. We confirm the previously seen cross-correlation between 3.6 μ m (4.5 μ m) and X-rays with 3.7 σ (4.2 σ ) and 2.7 σ (3.7 σ ) detections in the soft [0.5–2] keV and hard [2–8] keV X-ray bands, respectively, at angular scales above 20 arcsec. The cross-correlation of X-rays with Hubble is largely anticorrelated, ranging between the levels of 1.4 σ –3.5 σ for all the Hubble and X-ray bands. This lack of correlation in the shorter optical/NIR bands implies the sources responsible for the cosmic infrared background at 3.6 and 4.5 μ m are at least partly dissimilar to those at 1.6 μ m and shorter.

  13. Spitzer deep and wide legacy mid- and far-infrared number counts and lower limits of cosmic infrared background

    Science.gov (United States)

    Béthermin, M.; Dole, H.; Beelen, A.; Aussel, H.

    2010-03-01

    Aims: We aim to place stronger lower limits on the cosmic infrared background (CIB) brightness at 24 μm, 70 μm and 160 μm and measure the extragalactic number counts at these wavelengths in a homogeneous way from various surveys. Methods: Using Spitzer legacy data over 53.6 deg2 of various depths, we build catalogs with the same extraction method at each wavelength. Completeness and photometric accuracy are estimated with Monte-Carlo simulations. Number count uncertainties are estimated with a counts-in-cells moment method to take galaxy clustering into account. Furthermore, we use a stacking analysis to estimate number counts of sources not detected at 70 μm and 160 μm. This method is validated by simulations. The integration of the number counts gives new CIB lower limits. Results: Number counts reach 35 μJy, 3.5 mJy and 40 mJy at 24 μm, 70 μm, and 160 μm, respectively. We reach deeper flux densities of 0.38 mJy at 70, and 3.1 at 160 μm with a stacking analysis. We confirm the number count turnover at 24 μm and 70 μm, and observe it for the first time at 160 μm at about 20 mJy, together with a power-law behavior below 10 mJy. These mid- and far-infrared counts: 1) are homogeneously built by combining fields of different depths and sizes, providing a legacy over about three orders of magnitude in flux density; 2) are the deepest to date at 70 μm and 160 μm; 3) agree with previously published results in the common measured flux density range; 4) globally agree with the Lagache et al. (2004) model, except at 160 μm, where the model slightly overestimates the counts around 20 and 200 mJy. Conclusions: These counts are integrated to estimate new CIB firm lower limits of 2.29-0.09+0.09 nW m-2 sr-1, 5.4-0.4+0.4 nW m-2 sr-1, and 8.9-1.1+1.1 nW m-2 sr-1 at 24 μm, 70 μm, and 160 μm, respectively, and extrapolated to give new estimates of the CIB due to galaxies of 2.86-0.16+0.19 nW m-2 sr-1, 6.6-0.6+0.7 nW m-2 sr-1, and 14.6-2.9+7.1 nW m-2 sr-1

  14. Assembling the Infrared Extragalactic Background Light with CIBER-2: Probing Inter-Halo Light and the Epoch of Reionization.

    Science.gov (United States)

    Bock, James

    We propose to carry out a program of observations with the Cosmic Infrared Background Experiment (CIBER-2). CIBER-2 is a near-infrared sounding rocket experiment designed to measure spatial fluctuations in the extragalactic background light. CIBER-2 scientifically follows on the detection of fluctuations with the CIBER-1 imaging instrument, and will use measurement techniques developed and successfully demonstrated by CIBER-1. With high-sensitivity, multi-band imaging measurements, CIBER-2 will elucidate the history of interhalo light (IHL) production and carry out a deep search for extragalactic background fluctuations associated with the epoch of reionization (EOR). CIBER-1 has made high-quality detections of large-scale fluctuations over 4 sounding rocket flights. CIBER-1 measured the amplitude and spatial power spectrum of fluctuations, and observed an electromagnetic spectrum that is close to Rayleigh-Jeans, but with a statistically significant turnover at 1.1 um. The fluctuations cross-correlate with Spitzer images and are significantly bluer than the spectrum of the integrated background derived from galaxy counts. We interpret the CIBER-1 fluctuations as arising from IHL, low-mass stars tidally stripped from their parent galaxies during galaxy mergers. The first generation of stars and their remnants are likely responsible for the for the reionization of the intergalactic medium, observed to be ionized out to the most distant quasars at a redshift of 6. The total luminosity produced by first stars is uncertain, but a lower limit can be placed assuming a minimal number of photons to produce and sustain reionization. This 'minimal' extragalactic background component associated with reionization is detectable in fluctuations at the design sensitivity of CIBER-2. The CIBER-2 instrument is optimized for sensitivity to surface brightness in a short sounding rocket flight. The instrument consists of a 28 cm wide-field telescope operating in 6 spectral bands

  15. Real time imaging and infrared background scene analysis using the Naval Postgraduate School infrared search and target designation (NPS-IRSTD) system

    Science.gov (United States)

    Bernier, Jean D.

    1991-09-01

    The imaging in real time of infrared background scenes with the Naval Postgraduate School Infrared Search and Target Designation (NPS-IRSTD) System was achieved through extensive software developments in protected mode assembly language on an Intel 80386 33 MHz computer. The new software processes the 512 by 480 pixel images directly in the extended memory area of the computer where the DT-2861 frame grabber memory buffers are mapped. Direct interfacing, through a JDR-PR10 prototype card, between the frame grabber and the host computer AT bus enables each load of the frame grabber memory buffers to be effected under software control. The protected mode assembly language program can refresh the display of a six degree pseudo-color sector in the scanner rotation within the two second period of the scanner. A study of the imaging properties of the NPS-IRSTD is presented with preliminary work on image analysis and contrast enhancement of infrared background scenes.

  16. A Readout Integrated Circuit (ROIC) employing self-adaptive background current compensation technique for Infrared Focal Plane Array (IRFPA)

    Science.gov (United States)

    Zhou, Tong; Zhao, Jian; He, Yong; Jiang, Bo; Su, Yan

    2018-05-01

    A novel self-adaptive background current compensation circuit applied to infrared focal plane array is proposed in this paper, which can compensate the background current generated in different conditions. Designed double-threshold detection strategy is to estimate and eliminate the background currents, which could significantly reduce the hardware overhead and improve the uniformity among different pixels. In addition, the circuit is well compatible to various categories of infrared thermo-sensitive materials. The testing results of a 4 × 4 experimental chip showed that the proposed circuit achieves high precision, wide application and high intelligence. Tape-out of the 320 × 240 readout circuit, as well as the bonding, encapsulation and imaging verification of uncooled infrared focal plane array, have also been completed.

  17. Planck 2013 results. XXX. Cosmic infrared background measurements and implications for star formation

    Science.gov (United States)

    Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Armitage-Caplan, C.; Arnaud, M.; Ashdown, M.; Atrio-Barandela, F.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Bartlett, J. G.; Battaner, E.; Benabed, K.; Benoît, A.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bethermin, M.; Bielewicz, P.; Blagrave, K.; Bobin, J.; Bock, J. J.; Bonaldi, A.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Boulanger, F.; Bridges, M.; Bucher, M.; Burigana, C.; Butler, R. C.; Cardoso, J.-F.; Catalano, A.; Challinor, A.; Chamballu, A.; Chen, X.; Chiang, H. C.; Chiang, L.-Y.; Christensen, P. R.; Church, S.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Couchot, F.; Coulais, A.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Delouis, J.-M.; Désert, F.-X.; Dickinson, C.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Dupac, X.; Efstathiou, G.; Enßlin, T. A.; Eriksen, H. K.; Finelli, F.; Forni, O.; Frailis, M.; Franceschi, E.; Galeotta, S.; Ganga, K.; Ghosh, T.; Giard, M.; Giraud-Héraud, Y.; González-Nuevo, J.; Górski, K. M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Hansen, F. K.; Hanson, D.; Harrison, D.; Helou, G.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hornstrup, A.; Hovest, W.; Huffenberger, K. M.; Jaffe, A. H.; Jaffe, T. R.; Jones, W. C.; Juvela, M.; Kalberla, P.; Keihänen, E.; Kerp, J.; Keskitalo, R.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Knox, L.; Kunz, M.; Kurki-Suonio, H.; Lacasa, F.; Lagache, G.; Lähteenmäki, A.; Lamarre, J.-M.; Langer, M.; Lasenby, A.; Laureijs, R. J.; Lawrence, C. R.; Leonardi, R.; León-Tavares, J.; Lesgourgues, J.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Macías-Pérez, J. F.; Maffei, B.; Maino, D.; Mandolesi, N.; Maris, M.; Marshall, D. J.; Martin, P. G.; Martínez-González, E.; Masi, S.; Massardi, M.; Matarrese, S.; Matthai, F.; Mazzotta, P.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Mitra, S.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C. B.; Nørgaard-Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; Osborne, S.; Oxborrow, C. A.; Paci, F.; Pagano, L.; Pajot, F.; Paladini, R.; Paoletti, D.; Partridge, B.; Pasian, F.; Patanchon, G.; Perdereau, O.; Perotto, L.; Perrotta, F.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Ponthieu, N.; Popa, L.; Poutanen, T.; Pratt, G. W.; Prézeau, G.; Prunet, S.; Puget, J.-L.; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Reinecke, M.; Remazeilles, M.; Renault, C.; Ricciardi, S.; Riller, T.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Roudier, G.; Rowan-Robinson, M.; Rubiño-Martín, J. A.; Rusholme, B.; Sandri, M.; Santos, D.; Savini, G.; Scott, D.; Seiffert, M. D.; Serra, P.; Shellard, E. P. S.; Spencer, L. D.; Starck, J.-L.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sunyaev, R.; Sureau, F.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Tavagnacco, D.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Tuovinen, J.; Türler, M.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vielva, P.; Villa, F.; Vittorio, N.; Wade, L. A.; Wandelt, B. D.; Welikala, N.; White, M.; White, S. D. M.; Winkel, B.; Yvon, D.; Zacchei, A.; Zonca, A.

    2014-11-01

    We present new measurements of cosmic infrared background (CIB) anisotropies using Planck. Combining HFI data with IRAS, the angular auto- and cross-frequency power spectrum is measured from 143 to 3000 GHz, and the auto-bispectrum from 217 to 545 GHz. The total areas used to compute the CIB power spectrum and bispectrum are about 2240 and 4400 deg2, respectively. After careful removal of the contaminants (cosmic microwave background anisotropies, Galactic dust, and Sunyaev-Zeldovich emission), and a complete study of systematics, the CIB power spectrum is measured with unprecedented signal to noise ratio from angular multipoles ℓ ~ 150 to 2500. The bispectrum due to the clustering of dusty, star-forming galaxies is measured from ℓ ~ 130 to 1100, with a total signal to noise ratio of around 6, 19, and 29 at 217, 353, and 545 GHz, respectively. Two approaches are developed for modelling CIB power spectrum anisotropies. The first approach takes advantage of the unique measurements by Planck at large angular scales, and models only the linear part of the power spectrum, with a mean bias of dark matter haloes hosting dusty galaxies at a given redshift weighted by their contribution to the emissivities. The second approach is based on a model that associates star-forming galaxies with dark matter haloes and their subhaloes, using a parametrized relation between the dust-processed infrared luminosity and (sub-)halo mass. The two approaches simultaneously fit all auto- and cross-power spectra very well. We find that the star formation history is well constrained up to redshifts around 2, and agrees with recent estimates of the obscured star-formation density using Spitzer and Herschel. However, at higher redshift, the accuracy of the star formation history measurement is strongly degraded by the uncertainty in the spectral energy distribution of CIB galaxies. We also find that the mean halo mass which is most efficient at hosting star formation is log (Meff/M⊙) = 12

  18. BACKGROUNDER

    International Development Research Centre (IDRC) Digital Library (Canada)

    IDRC CRDI

    demographic trends, socio-economic development pathways, and strong ... knowledge and experience, and encourage innovation. ... choices, and will work with stakeholders in government, business, civil society, and regional economic.

  19. High-Energy Neutron Backgrounds for Underground Dark Matter Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yu [Syracuse Univ., NY (United States)

    2016-01-01

    Direct dark matter detection experiments usually have excellent capability to distinguish nuclear recoils, expected interactions with Weakly Interacting Massive Particle (WIMP) dark matter, and electronic recoils, so that they can efficiently reject background events such as gamma-rays and charged particles. However, both WIMPs and neutrons can induce nuclear recoils. Neutrons are then the most crucial background for direct dark matter detection. It is important to understand and account for all sources of neutron backgrounds when claiming a discovery of dark matter detection or reporting limits on the WIMP-nucleon cross section. One type of neutron background that is not well understood is the cosmogenic neutrons from muons interacting with the underground cavern rock and materials surrounding a dark matter detector. The Neutron Multiplicity Meter (NMM) is a water Cherenkov detector capable of measuring the cosmogenic neutron flux at the Soudan Underground Laboratory, which has an overburden of 2090 meters water equivalent. The NMM consists of two 2.2-tonne gadolinium-doped water tanks situated atop a 20-tonne lead target. It detects a high-energy (>~ 50 MeV) neutron via moderation and capture of the multiple secondary neutrons released when the former interacts in the lead target. The multiplicity of secondary neutrons for the high-energy neutron provides a benchmark for comparison to the current Monte Carlo predictions. Combining with the Monte Carlo simulation, the muon-induced high-energy neutron flux above 50 MeV is measured to be (1.3 ± 0.2) ~ 10-9 cm-2s-1, in reasonable agreement with the model prediction. The measured multiplicity spectrum agrees well with that of Monte Carlo simulation for multiplicity below 10, but shows an excess of approximately a factor of three over Monte Carlo prediction for multiplicities ~ 10 - 20. In an effort to reduce neutron backgrounds for the dark matter experiment SuperCDMS SNO- LAB, an active neutron veto was developed

  20. Studying the muon background component in the Double Chooz experiment

    Energy Technology Data Exchange (ETDEWEB)

    Dietrich, Dennis

    2013-03-28

    The reactor anti-neutrino experiment Double Chooz (DC) will measure the third neutrino mixing angle θ{sub 13} with very high precision. This mixing angle is connected to fundamental questions in particle physics beyond the current Standard Model. In DC neutrinos are detected via the Inverse Beta Decay reaction, which provides a clean signal distinguishable from most backgrounds. However, as neutrino interactions in the detector are very rare and an interfering muon background is present, a proper understanding and reduction of this background is mandatory. This is crucial because muons create fast neutrons and βn-emitters which lead to background capable of mimicking the neutrino interaction in the detector. This thesis covers different analysis topics related to the cosmic ray muon background at the DC far site. The thesis covers the identification of muons, the applied rejection technique and the determination of the muon rate at DC far site. Utilizing the muon rejection cuts of the neutrino analysis a muon rate of 13 s{sup -1} in the Inner Detector (ID) and of 46 s{sup -1} in the Inner Muon Veto (IV) was found. The efficiency of the IV to identify and reject cosmic ray muons was measured and a value greater than 99.97% has been found. The stability of the determined muon rates was examined and a seasonal modulation was found, compatible with a variation of the temperature profile of the atmosphere over the year. The parameter describing the strength between the relationship of temperature and muon rate change, the effective temperature coefficient was obtained: αT=0.39±0.01(stat.)±0.02(syst.). This gave the opportunity to measure the atmospheric kaon to pion ratio with the DC far detector which was found to be r(K/π)=0.14±0.06. Additional variations of muon rate with surface pressure were found and the barometric coefficient describing this effect was measured as βp=-0.59±0.20(stat.)±0.10(syst.) permille /mbar. Another central theme of this work was

  1. Studying the muon background component in the Double Chooz experiment

    International Nuclear Information System (INIS)

    Dietrich, Dennis

    2013-01-01

    The reactor anti-neutrino experiment Double Chooz (DC) will measure the third neutrino mixing angle θ 13 with very high precision. This mixing angle is connected to fundamental questions in particle physics beyond the current Standard Model. In DC neutrinos are detected via the Inverse Beta Decay reaction, which provides a clean signal distinguishable from most backgrounds. However, as neutrino interactions in the detector are very rare and an interfering muon background is present, a proper understanding and reduction of this background is mandatory. This is crucial because muons create fast neutrons and βn-emitters which lead to background capable of mimicking the neutrino interaction in the detector. This thesis covers different analysis topics related to the cosmic ray muon background at the DC far site. The thesis covers the identification of muons, the applied rejection technique and the determination of the muon rate at DC far site. Utilizing the muon rejection cuts of the neutrino analysis a muon rate of 13 s -1 in the Inner Detector (ID) and of 46 s -1 in the Inner Muon Veto (IV) was found. The efficiency of the IV to identify and reject cosmic ray muons was measured and a value greater than 99.97% has been found. The stability of the determined muon rates was examined and a seasonal modulation was found, compatible with a variation of the temperature profile of the atmosphere over the year. The parameter describing the strength between the relationship of temperature and muon rate change, the effective temperature coefficient was obtained: αT=0.39±0.01(stat.)±0.02(syst.). This gave the opportunity to measure the atmospheric kaon to pion ratio with the DC far detector which was found to be r(K/π)=0.14±0.06. Additional variations of muon rate with surface pressure were found and the barometric coefficient describing this effect was measured as βp=-0.59±0.20(stat.)±0.10(syst.) permille /mbar. Another central theme of this work was the extrapolation

  2. HerMES: COSMIC INFRARED BACKGROUND ANISOTROPIES AND THE CLUSTERING OF DUSTY STAR-FORMING GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Viero, M. P.; Zemcov, M.; Bock, J.; Cooray, A.; Dowell, C. D. [California Institute of Technology, 1200 E. California Blvd., Pasadena, CA 91125 (United States); Wang, L. [Institute for Computational Cosmology, Department of Physics, University of Durham, South Road, Durham, DH1 3LE (United Kingdom); Addison, G. [Department of Astrophysics, Denys Wilkinson Building, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom); Amblard, A. [NASA, Ames Research Center, Moffett Field, CA 94035 (United States); Arumugam, V. [Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); Aussel, H.; Bethermin, M. [Laboratoire AIM-Paris-Saclay, CEA/DSM/Irfu - CNRS - Universite Paris Diderot, CE-Saclay, pt courrier 131, F-91191 Gif-sur-Yvette (France); Boselli, A.; Buat, V.; Burgarella, D. [Laboratoire d' Astrophysique de Marseille - LAM, Universite d' Aix-Marseille and CNRS, UMR7326, 38 rue F. Joliot-Curie, F-13388 Marseille Cedex 13 (France); Casey, C. M. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Clements, D. L. [Astrophysics Group, Imperial College London, Blackett Laboratory, Prince Consort Road, London SW7 2AZ (United Kingdom); Conley, A. [Center for Astrophysics and Space Astronomy 389-UCB, University of Colorado, Boulder, CO 80309 (United States); Conversi, L. [Herschel Science Centre, European Space Astronomy Centre, Villanueva de la Canada, E-28691 Madrid (Spain); De Zotti, G. [INAF - Osservatorio Astronomico di Padova, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Farrah, D., E-mail: marco.viero@caltech.edu [Astronomy Centre, Dept. of Physics and Astronomy, University of Sussex, Brighton BN1 9QH (United Kingdom); and others

    2013-07-20

    We present measurements of the auto- and cross-frequency power spectra of the cosmic infrared background (CIB) at 250, 350, and 500 {mu}m (1200, 860, and 600 GHz) from observations totaling {approx}70 deg{sup 2} made with the SPIRE instrument aboard the Herschel Space Observatory. We measure a fractional anisotropy {delta}I/I = 14% {+-} 4%, detecting signatures arising from the clustering of dusty star-forming galaxies in both the linear (2-halo) and nonlinear (1-halo) regimes; and that the transition from the 2- to 1-halo terms, below which power originates predominantly from multiple galaxies within dark matter halos, occurs at k{sub {theta}} {approx} 0.10-0.12 arcmin{sup -1} (l {approx} 2160-2380), from 250 to 500 {mu}m. New to this paper is clear evidence of a dependence of the Poisson and 1-halo power on the flux-cut level of masked sources-suggesting that some fraction of the more luminous sources occupy more massive halos as satellites, or are possibly close pairs. We measure the cross-correlation power spectra between bands, finding that bands which are farthest apart are the least correlated, as well as hints of a reduction in the correlation between bands when resolved sources are more aggressively masked. In the second part of the paper, we attempt to interpret the measurements in the framework of the halo model. With the aim of fitting simultaneously with one model the power spectra, number counts, and absolute CIB level in all bands, we find that this is achievable by invoking a luminosity-mass relationship, such that the luminosity-to-mass ratio peaks at a particular halo mass scale and declines toward lower and higher mass halos. Our best-fit model finds that the halo mass which is most efficient at hosting star formation in the redshift range of peak star-forming activity, z {approx} 1-3, is log(M{sub peak}/M{sub Sun }) {approx} 12.1 {+-} 0.5, and that the minimum halo mass to host infrared galaxies is log(M{sub min}/M{sub Sun }) {approx} 10

  3. The cryogenic photon detection system for the ALPS II experiment. Characterization, optimization and background rejection

    International Nuclear Information System (INIS)

    Bastidon, Noemi Alice Chloe

    2017-01-01

    The search for new fundamental bosons at very low mass is the central objective of the ALPS II experiment which is currently set up at the Deutsches Elektronen-Synchrotron (DESY, Hamburg). This experiment follows the light-shining-through-the-wall concept where photons could oscillate into weakly interacting light bosons in front of a wall and back into photons behind the wall, giving the impression that light can shine through a light tight barrier. In this concept, the background-free detection of near-infrared photons is required to fully exploit the sensitivity of the apparatus. The high efficiency single-photon detection in the near-infrared is challenging and requires a cryogenic detector. In this project, a Transition-Edge Sensor (TES) operated below 100mK will be used to detect single photons. This thesis focuses on the characterization and optimization of the ALPS II detector system including an Adiabatic Demagnetisation Refrigerator (ADR) with its two-stage pulse-tube cooler, two TES detectors and their Superconducting Quantum Interference Devices (SQUIDs) read-out system. Stability of the detection system over time is a priority in the ALPS II experiment. It is in this context that the cooling system has been subjected to many upgrades. In the framework of this thesis, the cooling setup has been studied in detail in order to optimize its cooling performances. Furthermore, the stability of the detector has been studied according to various criteria. Other essential parameters of the ALPS II experiment are its detection efficiency and its background rate. Indeed, the sensitivity of the experiment directly depends on these two characteristics. Both elements have been studied in depth in order to define if the chosen TES detector will meet ALPS IIc specifications.

  4. The cryogenic photon detection system for the ALPS II experiment. Characterization, optimization and background rejection

    Energy Technology Data Exchange (ETDEWEB)

    Bastidon, Noemi Alice Chloe

    2017-01-12

    The search for new fundamental bosons at very low mass is the central objective of the ALPS II experiment which is currently set up at the Deutsches Elektronen-Synchrotron (DESY, Hamburg). This experiment follows the light-shining-through-the-wall concept where photons could oscillate into weakly interacting light bosons in front of a wall and back into photons behind the wall, giving the impression that light can shine through a light tight barrier. In this concept, the background-free detection of near-infrared photons is required to fully exploit the sensitivity of the apparatus. The high efficiency single-photon detection in the near-infrared is challenging and requires a cryogenic detector. In this project, a Transition-Edge Sensor (TES) operated below 100mK will be used to detect single photons. This thesis focuses on the characterization and optimization of the ALPS II detector system including an Adiabatic Demagnetisation Refrigerator (ADR) with its two-stage pulse-tube cooler, two TES detectors and their Superconducting Quantum Interference Devices (SQUIDs) read-out system. Stability of the detection system over time is a priority in the ALPS II experiment. It is in this context that the cooling system has been subjected to many upgrades. In the framework of this thesis, the cooling setup has been studied in detail in order to optimize its cooling performances. Furthermore, the stability of the detector has been studied according to various criteria. Other essential parameters of the ALPS II experiment are its detection efficiency and its background rate. Indeed, the sensitivity of the experiment directly depends on these two characteristics. Both elements have been studied in depth in order to define if the chosen TES detector will meet ALPS IIc specifications.

  5. Peculiar velocity effects in high-resolution microwave background experiments

    International Nuclear Information System (INIS)

    Challinor, Anthony; Leeuwen, Floor van

    2002-01-01

    We investigate the impact of peculiar velocity effects due to the motion of the solar system relative to the cosmic microwave background (CMB) on high resolution CMB experiments. It is well known that on the largest angular scales the combined effects of Doppler shifts and aberration are important; the lowest Legendre multipoles of total intensity receive power from the large CMB monopole in transforming from the CMB frame. On small angular scales aberration dominates and is shown here to lead to significant distortions of the total intensity and polarization multipoles in transforming from the rest frame of the CMB to the frame of the solar system. We provide convenient analytic results for the distortions as series expansions in the relative velocity of the two frames, but at the highest resolutions a numerical quadrature is required. Although many of the high resolution multipoles themselves are severely distorted by the frame transformations, we show that their statistical properties distort by only an insignificant amount. Therefore, the cosmological parameter estimation is insensitive to the transformation from the CMB frame (where theoretical predictions are calculated) to the rest frame of the experiment

  6. Self-calibration of Cosmic Microwave Background Polarization Experiments

    Science.gov (United States)

    Keating, Brian G.; Shimon, Meir; Yadav, Amit P. S.

    2013-01-01

    Precision measurements of the polarization of the cosmic microwave background (CMB) radiation, especially experiments seeking to detect the odd-parity "B-modes," have far-reaching implications for cosmology. To detect the B-modes generated during inflation, the flux response and polarization angle of these experiments must be calibrated to exquisite precision. While suitable flux calibration sources abound, polarization angle calibrators are deficient in many respects. Man-made polarized sources are often not located in the antenna's far-field, have spectral properties that are radically different from the CMB's, are cumbersome to implement, and may be inherently unstable over the (long) duration these searches require to detect the faint signature of the inflationary epoch. Astrophysical sources suffer from time, frequency, and spatial variability, are not visible from all CMB observatories, and none are understood with sufficient accuracy to calibrate future CMB polarimeters seeking to probe inflationary energy scales of 1015 GeV. Both man-made and astrophysical sources require dedicated observations which detract from the amount of integration time usable for detection of the inflationary B-modes. CMB TB and EB modes, expected to identically vanish in the standard cosmological model, can be used to calibrate CMB polarimeters. By enforcing the observed EB and TB power spectra to be consistent with zero, CMB polarimeters can be calibrated to levels not possible with man-made or astrophysical sources. All of this can be accomplished for any polarimeter without any loss of observing time using a calibration source which is spectrally identical to the CMB B-modes.

  7. Experiments with background gas in a vacuum arc centrifuge

    International Nuclear Information System (INIS)

    Dallaqua, R.S.; Simpson, S.W.; Del Bosco, E.

    1996-01-01

    Since promising isotope separation results were first reported by Krishnan et al. in 1981, a range of vacuum arc centrifuge experiments have been conducted in laboratories around the world. The PCEN (Plasma CENtrifuge) vacuum arc centrifuge at the Brazilian National Institute for Space Research has been used for isotope separation studies with cathode materials of carbon and magnesium and also to investigate the performance in terms of the rotational velocity attained for different cathode materials. Here, a vacuum arc centrifuge has been operated with an initial filling gas of either argon or hydrogen for pressures ranging from 10 -3 to 10 -1 Pa. The angular velocity ω of the plasma has been determined by cross-correlating the signals from potential probes, and the electron temperature T has been deduced from Langmuir probe data. At high gas pressures and early times during the 14 ms plasma lifetime, high-frequency nonuniformities frequently observed in the vacuum discharge disappear, suggesting that the associated instability is suppressed. Under the same conditions, nonuniformities rotating with much lower angular velocities are observed in the plasma. Temperatures are reduced in the presence of the background gas, and the theoretical figure of merit for separation proportional to ω 2 /T is increased compared to its value in the vacuum discharge for both argon and hydrogen gas fillings

  8. Purification of cerium, neodymium and gadolinium for low background experiments

    Directory of Open Access Journals (Sweden)

    Boiko R.S.

    2014-01-01

    Full Text Available Cerium, neodymium and gadolinium contain double beta active isotopes. The most interesting are 150Nd and 160Gd (promising for 0ν2β search, 136Ce (2β+ candidate with one of the highest Q2β. The main problem of compounds containing lanthanide elements is their high radioactive contamination by uranium, radium, actinium and thorium. The new generation 2β experiments require development of methods for a deep purification of lanthanides from the radioactive elements. A combination of physical and chemical methods was applied to purify cerium, neodymium and gadolinium. Liquid-liquid extraction technique was used to remove traces of Th and U from neodymium, gadolinium and for purification of cerium from Th, U, Ra and K. Co-precipitation and recrystallization methods were utilized for further reduction of the impurities. The radioactive contamination of the samples before and after the purification was tested by using ultra-low-background HPGe gamma spectrometry. As a result of the purification procedure the radioactive contamination of gadolinium oxide (a similar purification efficiency was reached also with cerium and neodymium oxides was decreased from 0.12 Bq/kg to 0.007 Bq/kg in 228Th, from 0.04 Bq/kg to <0.006 Bq/kg in 226Ra, and from 0.9 Bq/kg to 0.04 Bq/kg in 40K. The purification methods are much less efficient for chemically very similar radioactive elements like actinium, lanthanum and lutetium.

  9. High spatial resolution infrared camera as ISS external experiment

    Science.gov (United States)

    Eckehard, Lorenz; Frerker, Hap; Fitch, Robert Alan

    High spatial resolution infrared camera as ISS external experiment for monitoring global climate changes uses ISS internal and external resources (eg. data storage). The optical experiment will consist of an infrared camera for monitoring global climate changes from the ISS. This technology was evaluated by the German small satellite mission BIRD and further developed in different ESA projects. Compared to BIRD the presended instrument uses proven sensor advanced technologies (ISS external) and ISS on board processing and storage capabili-ties (internal). The instrument will be equipped with a serial interfaces for TM/TC and several relay commands for the power supply. For data processing and storage a mass memory is re-quired. The access to actual attitude data is highly desired to produce geo referenced maps-if possible by an on board processing.

  10. Infrared images target detection based on background modeling in the discrete cosine domain

    Science.gov (United States)

    Ye, Han; Pei, Jihong

    2018-02-01

    Background modeling is the critical technology to detect the moving target for video surveillance. Most background modeling techniques are aimed at land monitoring and operated in the spatial domain. A background establishment becomes difficult when the scene is a complex fluctuating sea surface. In this paper, the background stability and separability between target are analyzed deeply in the discrete cosine transform (DCT) domain, on this basis, we propose a background modeling method. The proposed method models each frequency point as a single Gaussian model to represent background, and the target is extracted by suppressing the background coefficients. Experimental results show that our approach can establish an accurate background model for seawater, and the detection results outperform other background modeling methods in the spatial domain.

  11. Background and state of the art of near infrared spectroscopy in the forest sector base

    International Nuclear Information System (INIS)

    Muñiz, G.I.B. de; Magalhães, W.L.E.; Carneiro, M.E.; Viana, L.C.

    2012-01-01

    The knowledge of wood properties is the fundamental importance for the indication of the potential and use of this material. In the search for new alternatives for a fast, simple and reliable characterization, there are the non-destructive evaluations of wood. The near infrared spectroscopy (NIRS) has been used as a non-destructive method that allows qualitative and quantitative information of the constituents of biomass through the interaction of electromagnetic waves with near-infrared next to the sample. This work aims to provide a review of the technique of near infrared spectroscopy and its application in forestry. The technique is used in virtually all areas due to the level of development that this technology has reached in recent years. NIR spectroscopy has proved a quick and efficient replacement of several tests that determine the quality of the wood. This is a literature review and state of the art on the theme [pt

  12. First-Light Galaxies or Intrahalo Stars: Multi-Wavelength Measurements of the Infrared Background Anisotropies

    Science.gov (United States)

    Cooray, Asantha

    explained with DGL. The proposed research supports Goal 2 of the NASA 2011 Strategic Plan to Expand scientific understanding of the Earth and the universe which we live, specifically to address the sub-goal 2.4 to discover how the universe works and explore how it began and evolved. The proposal is relevant to NASA's 2007 Science Plan in addressing the Science Question How do planets, stars, galaxies, and cosmic structure come into being?. The training of next-generation astrophysicists in the form of undergraduate students, graduate students, and postdoctoral fellows leading to experience and background in the analysis and interpretation of space-based astronomical data support the Goal 6 of the NASA 2011 Strategic Plan to Share NASA with the public, educators, and students to provide opportunities to participate in our Mission, foster innovation, and contribute to a strong national economy. The PI's efforts to involve undergraduates in his research programs will specifically improve retention of students in STEM disciplines by providing opportunities and activities along the full length of the education pipeline (subgoal 6.1). The IR fluctuation study supports JWST, Euclid, and WFIRST since we study the ensemble properties of the faint emission buried in existing deep and wide space-based IR data. We expect some fraction of the fluctuations to be from first-light galaxies that JWST seeks to detect and characterize individually. Euclid and WFIRST can make very deep and wide multi-band fluctuation measurements, depending on the final choice of bands (WFIRST) and observation/deep-field strategy (Euclid and WFIRST). This work could also motivate a small instrument for space-borne measurement of the absolute sky brightness from 5 AU, where the Zodiacal foreground is expected to be 100 times fainter than at 1.

  13. BACKGROUND AND STATE OF THEE ART OF NEAR INFRARED SPECTROSCOPY IN THE FOREST SECTOR BASE

    Directory of Open Access Journals (Sweden)

    Graciela Inês Bolzon de Muñiz

    2012-12-01

    Full Text Available http://dx.doi.org/10.5902/198050987567The knowledge of wood properties is the fundamental importance for the indication of the potential and use of this material. In the search for new alternatives for a fast, simple and reliable characterization, there are the non-destructive evaluations of wood. The near infrared spectroscopy (NIRS has been used as a non-destructive method that allows qualitative and quantitative information of the constituents of biomass through the interaction of electromagnetic waves with near-infrared next to the sample. This work aims to provide a review of the technique of near infrared spectroscopy and its application in forestry. The technique is used in virtually all areas due to the level of development that this technology has reached in recent years. NIR spectroscopy has proved a quick and efficient replacement of several tests that determine the quality of the wood. This is a literature review and state of the art on the theme.

  14. Experiences of School Belonging for Young Children with Refugee Backgrounds

    Science.gov (United States)

    Due, Clemence; Riggs, Damien W.; Augoustinos, Martha

    2016-01-01

    Previous research with adolescents with refugee backgrounds living in countries of resettlement has found that school belonging has an impact on a range of well-being and developmental outcomes, including mental health, peer relationships, self-esteem and self-efficacy, and academic achievement. However, very little research has explored school…

  15. The Ĝ Infrared Search for Extraterrestrial Civilizations with Large Energy Supplies. I. Background and Justification

    Science.gov (United States)

    Wright, J. T.; Mullan, B.; Sigurdsson, S.; Povich, M. S.

    2014-09-01

    We motivate the Ĝ infrared search for extraterrestrial civilizations with large energy supplies. We discuss some philosophical difficulties of the search for extraterrestrial intelligence (SETI), and how communication SETI circumvents them. We review "Dysonian SETI," the search for artifacts of alien civilizations, and find that it is highly complementary to traditional communication SETI; the two together might succeed where either one alone has not. We discuss the argument of Hart that spacefaring life in the Milky Way should be either galaxy-spanning or non-existent, and examine a portion of his argument that we call the "monocultural fallacy." We discuss some rebuttals to Hart that invoke sustainability and predict long Galaxy colonization timescales. We find that the maximum Galaxy colonization timescale is actually much shorter than previous work has found (energy supplies and argue that detectably large energy supplies can plausibly be expected to exist because life has the potential for exponential growth until checked by resources or other limitations, and intelligence implies the ability to overcome such limitations. As such, if Hart's thesis is correct, then searches for large alien civilizations in other galaxies may be fruitful; if it is incorrect, then searches for civilizations within the Milky Way are more likely to succeed than Hart argued. We review some past Dysonian SETI efforts and discuss the promise of new mid-infrared surveys, such as that of WISE.

  16. Research on infrared small-target tracking technology under complex background

    Science.gov (United States)

    Liu, Lei; Wang, Xin; Chen, Jilu; Pan, Tao

    2012-10-01

    In this paper, some basic principles and the implementing flow charts of a series of algorithms for target tracking are described. On the foundation of above works, a moving target tracking software base on the OpenCV is developed by the software developing platform MFC. Three kinds of tracking algorithms are integrated in this software. These two tracking algorithms are Kalman Filter tracking method and Camshift tracking method. In order to explain the software clearly, the framework and the function are described in this paper. At last, the implementing processes and results are analyzed, and those algorithms for tracking targets are evaluated from the two aspects of subjective and objective. This paper is very significant in the application of the infrared target tracking technology.

  17. The Ĝ infrared search for extraterrestrial civilizations with large energy supplies. I. Background and justification

    International Nuclear Information System (INIS)

    Wright, J. T.; Mullan, B.; Sigurdsson, S.; Povich, M. S.

    2014-01-01

    We motivate the Ĝ infrared search for extraterrestrial civilizations with large energy supplies. We discuss some philosophical difficulties of the search for extraterrestrial intelligence (SETI), and how communication SETI circumvents them. We review 'Dysonian SETI', the search for artifacts of alien civilizations, and find that it is highly complementary to traditional communication SETI; the two together might succeed where either one alone has not. We discuss the argument of Hart that spacefaring life in the Milky Way should be either galaxy-spanning or non-existent, and examine a portion of his argument that we call the 'monocultural fallacy'. We discuss some rebuttals to Hart that invoke sustainability and predict long Galaxy colonization timescales. We find that the maximum Galaxy colonization timescale is actually much shorter than previous work has found (<10 9 yr), and that many 'sustainability' counter-arguments to Hart's thesis suffer from the monocultural fallacy. We extend Hart's argument to alien energy supplies and argue that detectably large energy supplies can plausibly be expected to exist because life has the potential for exponential growth until checked by resources or other limitations, and intelligence implies the ability to overcome such limitations. As such, if Hart's thesis is correct, then searches for large alien civilizations in other galaxies may be fruitful; if it is incorrect, then searches for civilizations within the Milky Way are more likely to succeed than Hart argued. We review some past Dysonian SETI efforts and discuss the promise of new mid-infrared surveys, such as that of WISE.

  18. Identification and age estimation of blood stains on colored backgrounds by near infrared spectroscopy

    NARCIS (Netherlands)

    Edelman, Gerda; Manti, Vicky; van Ruth, Saskia M.; van Leeuwen, Ton; Aalders, Maurice

    2012-01-01

    Non-destructive identification and subsequent age estimation of blood stains are significant steps in forensic casework. The latter can provide important information on the temporal aspects of a crime. As previously shown, visible spectroscopy of blood stains on white backgrounds can successfully be

  19. The moderately fractured rock experiment: Background and overview

    International Nuclear Information System (INIS)

    Jensen, M.R.

    2001-01-01

    The Moderately Fractured Rock (MFR) experiment is conducted at Atomic Energy of Canada Limited's Underground Research Laboratory (URL) as part of Ontario Power Generation's Deep Geologic Repository Technology Program. The MFR experiment was initiated in the mid-1990s with the purpose of advancing the understanding of mass transport in MFR (fractures 1-5/m, k ≅ 10 -15 m 2 ) in which groundwater flow and solute migration occurs through a network of interconnected fractures. The experimental program has involved a series of multi-well forced gradient tracer tests at scales of 10-50 m within a ≅ 100,000 m 3 volume of MFR accessed from the 240 m level of the URL. The tracer tests conducted with non-reactive, reactive and colloidal tracers have served to explore the applicability of continuum models for prediction of groundwater flow and mass transport. Recently, a Modeling Task Force was created to re-examine tracer test experimental methodologies, MFR flow and transport conceptual models and provide a broader forum in which to apply alternative dual-permeability, discrete fracture and hybrid mathematical codes for flow system analysis. This paper provides a description of the MFR experiment, preliminary research findings and plans for the future

  20. Development of Fast, Background-Limited Transition-Edge Sensors for the Background-Limited Infrared/Sub-Millimetre Spectrograph (BLISS) for SPICA

    Science.gov (United States)

    Beyer, Andrew D.; Runyan, M. C.; Kenyon, M.; Echternach, P. M.; Chui, T.; Bumble, B.; Bradford, C. M.; Holmes, W. A.; Bock, J. J.

    2012-01-01

    We report experimental progress toward demonstrating background-limited arrays of membrane-isolated transition-edge sensors (TESs) for the Background Limited Infrared/Sub-mm Spectrograph (BLISS). BLISS is a space-borne instrument with grating spectrometers for wavelengths lambda = 35-435 microns and with R = lambda/(delta)lambda approx. 500. The goals for BLISS TESs are: noise equivalent power (NEP) = 5x10(exp -20) W/Hz(1/2) and response time t or = 135mK) and Mo/Cu proximitized bilayers, where T(sub c) is the thermistor transition temperature. We measured the Ir TES arrays in our 50mK adiabatic demagnetization refrigerator test system, which can measure up to eight 1x32 arrays simultaneously using a time-division multiplexer, as well as our single-pixel test system which can measure down to 15mK. In our previous Ir array measurements our best reported performance was NEP=2.5x10(exp -19) W/Hz(1/2) and tapprox.5ms for straight-beam TESs. In fact, we expected NEPapprox.1.5x10(exp -19)W/Hz(1/2) for meander beam TESs, but did not achieve this previously due to 1/f noise. Here, we detail improvements toward measuring the expected NEP and demonstrate NEP=(1.3+0.2)x10(exp -19)W/Hz(1/2) in our single-pixel test system and NEP=(1.6+0.3)x10(exp -19)W/Hz(1/2) in our array test system.

  1. Development of Fast, Background-Limited Transition-Edge Sensors for the Background-Limited Infrared/Sub-mm Spectrograph (BLISS) for SPICA

    Science.gov (United States)

    Beyer, Andrew D.; Runyan, M. C.; Kenyon, M.; Echternach, P. M .; Chui, T.; Bumble, B.; Bradford, C. M.; Holmes, W. A.; Bock, J. J.

    2012-01-01

    We report experimental progress toward demonstrating background-limited arrays of membrane-isolated transition-edge sensors (TESs) for the Background Limited Infrared/Sub-mm Spectrograph (BLISS). BLISS is a space-borne instrument with grating spectrometers for wavelengths lambda=35-435 micron and with R=lambda/delta lambda approximately equals 500. The goals for BLISS TESs are: noise equivalent power (NEP) = 5x10 (sup -20) W/Hz(exp 1/2) and response time tau = 135mK) and Mo/Cu proximitized bilayers, where T(sub c) is the thermistor transition temperature. We measured the Ir TES arrays in our 50mK adiabatic demagnetization refrigerator test system, which can measure up to eight 1x32 arrays simultaneously using a time-division multiplexer, as well as our single-pixel test system which can measure down to 15mK. In our previous Ir array measurements our best reported performance was NEP=2.5x10(exp -19) W/Hz(sub 1/2) and Tau approximately equals 5ms for straight-beam TESs. In fact, we expected NEP approximately equals 1.5x10(exp -19)?W/Hz(sup 1/2) for meander beam TESs, but did not achieve this previously due to 1/f noise. Here, we detail improvements toward measuring the expected NEP and demonstrate NEP=(1.3+0.2)x10 (sup -19)W/Hz(exp 1/2) in our single-pixel test system and NEP=(1.6+/-0.3)x10(sup -19)W/Hz(sup 1/2) in our array test system.

  2. Human Detection Based on the Generation of a Background Image by Using a Far-Infrared Light Camera

    Directory of Open Access Journals (Sweden)

    Eun Som Jeon

    2015-03-01

    Full Text Available The need for computer vision-based human detection has increased in fields, such as security, intelligent surveillance and monitoring systems. However, performance enhancement of human detection based on visible light cameras is limited, because of factors, such as nonuniform illumination, shadows and low external light in the evening and night. Consequently, human detection based on thermal (far-infrared light cameras has been considered as an alternative. However, its performance is influenced by the factors, such as low image resolution, low contrast and the large noises of thermal images. It is also affected by the high temperature of backgrounds during the day. To solve these problems, we propose a new method for detecting human areas in thermal camera images. Compared to previous works, the proposed research is novel in the following four aspects. One background image is generated by median and average filtering. Additional filtering procedures based on maximum gray level, size filtering and region erasing are applied to remove the human areas from the background image. Secondly, candidate human regions in the input image are located by combining the pixel and edge difference images between the input and background images. The thresholds for the difference images are adaptively determined based on the brightness of the generated background image. Noise components are removed by component labeling, a morphological operation and size filtering. Third, detected areas that may have more than two human regions are merged or separated based on the information in the horizontal and vertical histograms of the detected area. This procedure is adaptively operated based on the brightness of the generated background image. Fourth, a further procedure for the separation and removal of the candidate human regions is performed based on the size and ratio of the height to width information of the candidate regions considering the camera viewing direction

  3. Probing reionization with the cross-power spectrum of 21 cm and near-infrared radiation backgrounds

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Xiao-Chun, E-mail: xcmao@bao.ac.cn [National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

    2014-08-01

    The cross-correlation between the 21 cm emission from the high-redshift intergalactic medium and the near-infrared (NIR) background light from high-redshift galaxies promises to be a powerful probe of cosmic reionization. In this paper, we investigate the cross-power spectrum during the epoch of reionization. We employ an improved halo approach to derive the distribution of the density field and consider two stellar populations in the star formation model: metal-free stars and metal-poor stars. The reionization history is further generated to be consistent with the electron-scattering optical depth from cosmic microwave background measurements. Then, the intensity of the NIR background is estimated by collecting emission from stars in first-light galaxies. On large scales, we find that the 21 cm and NIR radiation backgrounds are positively correlated during the very early stages of reionization. However, these two radiation backgrounds quickly become anti-correlated as reionization proceeds. The maximum absolute value of the cross-power spectrum is |Δ{sub 21,NIR}{sup 2}|∼10{sup −4} mK nW m{sup –2} sr{sup –1}, reached at ℓ ∼ 1000 when the mean fraction of ionized hydrogen is x-bar{sub i}∼0.9. We find that Square Kilometer Array can measure the 21 cm-NIR cross-power spectrum in conjunction with mild extensions to the existing CIBER survey, provided that the integration time independently adds up to 1000 and 1 hr for 21 cm and NIR observations, and that the sky coverage fraction of the CIBER survey is extended from 4 × 10{sup –4} to 0.1. Measuring the cross-correlation signal as a function of redshift provides valuable information on reionization and helps confirm the origin of the 'missing' NIR background.

  4. Simulation of signal and background processes for collider experiments

    International Nuclear Information System (INIS)

    Schumann, S.

    2008-01-01

    In this thesis new theoretical tools for the accurate simulation of scattering processes at present and future collider experiments have been developed. Special emphasis has thereby to be given to multi-particle/multi-jet final states that often constitute signals for interesting (new) physics. Considering final states with a number of hard jets, there seems to be enough evidence that the traditional simulation tools HERWIG and PYTHIA cannot fully accomplish their description. Starting from a 2→2 core process, they account only for soft and collinear QCD emissions through parton-shower models. Only recently, theoretical prescriptions have been found to consistently combine tree-level matrix-element calculations with the existing parton-shower algorithms. The gain of such methods is that phase-space regions covered by hard and by soft parton kinematics are simultaneously well described. In Chapter 2 of this thesis the working principles of such prescriptions have been discussed with special attention being paid to the merging scheme implemented in the SHERPA Monte Carlo. To consistently match QCD higher-order calculations (at one-loop or tree-level) with parton showers, a good analytical control over the perturbative terms present in the latter is required. This has triggered the demand for improved parton-shower models that facilitate the inclusion of exact matrix elements. In this line a completely new shower algorithm has been presented in Chapter 3. It is based on the Catani-Seymour dipole subtraction formalism, a universal method for calculating arbitrary processes at next-to-leading order in QCD. The splitting kernels used in the shower are justified approximations of the Catani-Seymour dipole functions. The kinematics of the individual splittings is accomplished such that exact four-momentum conservation can be ensured for each single branching. Accordingly, the shower can be stopped and started again at each intermediate stage of the evolution. The model

  5. Simulation of signal and background processes for collider experiments

    Energy Technology Data Exchange (ETDEWEB)

    Schumann, S.

    2008-10-08

    In this thesis new theoretical tools for the accurate simulation of scattering processes at present and future collider experiments have been developed. Special emphasis has thereby to be given to multi-particle/multi-jet final states that often constitute signals for interesting (new) physics. Considering final states with a number of hard jets, there seems to be enough evidence that the traditional simulation tools HERWIG and PYTHIA cannot fully accomplish their description. Starting from a 2{yields}2 core process, they account only for soft and collinear QCD emissions through parton-shower models. Only recently, theoretical prescriptions have been found to consistently combine tree-level matrix-element calculations with the existing parton-shower algorithms. The gain of such methods is that phase-space regions covered by hard and by soft parton kinematics are simultaneously well described. In Chapter 2 of this thesis the working principles of such prescriptions have been discussed with special attention being paid to the merging scheme implemented in the SHERPA Monte Carlo. To consistently match QCD higher-order calculations (at one-loop or tree-level) with parton showers, a good analytical control over the perturbative terms present in the latter is required. This has triggered the demand for improved parton-shower models that facilitate the inclusion of exact matrix elements. In this line a completely new shower algorithm has been presented in Chapter 3. It is based on the Catani-Seymour dipole subtraction formalism, a universal method for calculating arbitrary processes at next-to-leading order in QCD. The splitting kernels used in the shower are justified approximations of the Catani-Seymour dipole functions. The kinematics of the individual splittings is accomplished such that exact four-momentum conservation can be ensured for each single branching. Accordingly, the shower can be stopped and started again at each intermediate stage of the evolution. The

  6. Infrared-faint radio sources: a cosmological view. AGN number counts, the cosmic X-ray background and SMBH formation

    Science.gov (United States)

    Zinn, P.-C.; Middelberg, E.; Ibar, E.

    2011-07-01

    Context. Infrared-faint radio sources (IFRS) are extragalactic emitters clearly detected at radio wavelengths but barely detected or undetected at optical and infrared wavelengths, with 5σ sensitivities as low as 1 μJy. Aims: Spectral energy distribution (hereafter SED) modelling and analyses of their radio properties indicate that IFRS are consistent with a population of (potentially extremely obscured) high-redshift AGN at 3 ≤ z ≤ 6. We demonstrate some astrophysical implications of this population and compare them to predictions from models of galaxy evolution and structure formation. Methods: We compiled a list of IFRS from four deep extragalactic surveys and extrapolated the IFRS number density to a survey-independent value of (30.8 ± 15.0) deg-2. We computed the IFRS contribution to the total number of AGN in the Universe to account for the cosmic X-ray background. By estimating the black hole mass contained in IFRS, we present conclusions for the SMBH mass density in the early universe and compare it to relevant simulations of structure formation after the Big Bang. Results: The number density of AGN derived from the IFRS density was found to be ~310 deg-2, which is equivalent to a SMBH mass density of the order of 103 M⊙ Mpc-3 in the redshift range 3 ≤ z ≤ 6. This produces an X-ray flux of 9 × 10-16 W m-2 deg-2 in the 0.5-2.0 keV band and 3 × 10-15 W m-2 deg-2 in the 2.0-10 keV band, in agreement with the missing unresolved components of the Cosmic X-ray Background. To address SMBH formation after the Big Bang we invoke a scenario involving both halo gas accretion and major mergers.

  7. The noise background and its suppression in high energy physics experiment

    International Nuclear Information System (INIS)

    Meng Xiangcheng

    1996-01-01

    In the modern high energy physics experiments, system is very complicated and from a lot of sources may originate noise and background. How to reduce and restrain noise and backgrounds? It should use different suppression mode for different kinds of noise and backgrounds

  8. PROBING THE EPOCH OF PRE-REIONIZATION BY CROSS-CORRELATING COSMIC MICROWAVE AND INFRARED BACKGROUND ANISOTROPIES

    International Nuclear Information System (INIS)

    Atrio-Barandela, F.; Kashlinsky, A.

    2014-01-01

    The epoch of first star formation and the state of the intergalactic medium (IGM) at that time are not directly observable with current telescopes. The radiation from those early sources is now part of the cosmic infrared background (CIB) and, as these sources ionize the gas around them, the IGM plasma would produce faint temperature anisotropies in the cosmic microwave background (CMB) via the thermal Sunyaev-Zeldovich (TSZ) effect. While these TSZ anisotropies are too faint to be detected, we show that the cross-correlation of maps of source-subtracted CIB fluctuations from Euclid, with suitably constructed microwave maps at different frequencies, can probe the physical state of the gas during reionization and test/constrain models of the early CIB sources. We identify the frequency-combined, CMB-subtracted microwave maps from space- and ground-based instruments to show that they can be cross-correlated with the forthcoming all-sky Euclid CIB maps to detect the cross-power at scales ∼5'-60' with signal-to-noise ratios (S/Ns) of up to S/N ∼ 4-8 depending on the contribution to the Thomson optical depth during those pre-reionization epochs (Δτ ≅ 0.05) and the temperature of the IGM (up to ∼10 4 K). Such a measurement would offer a new window to explore the emergence and physical properties of these first light sources

  9. Mitigation of ^{42}Ar/^{42}K background for the GERDA Phase II experiment

    Science.gov (United States)

    Lubashevskiy, A.; Agostini, M.; Budjáš, D.; Gangapshev, A.; Gusev, K.; Heisel, M.; Klimenko, A.; Lazzaro, A.; Lehnert, B.; Pelczar, K.; Schönert, S.; Smolnikov, A.; Walter, M.; Zuzel, G.

    2018-01-01

    Background coming from the ^{42}Ar decay chain is considered to be one of the most relevant for the Gerda experiment, which searches for the neutrinoless double beta decay of ^{76}Ge. The sensitivity strongly relies on the absence of background around the Q-value of the decay. Background coming from ^{42}K, a progeny of ^{42}Ar, can contribute to that background via electrons from the continuous spectrum with an endpoint at 3.5 MeV. Research and development on the suppression methods targeting this source of background were performed at the low-background test facility LArGe . It was demonstrated that by reducing ^{42}K ion collection on the surfaces of the broad energy germanium detectors in combination with pulse shape discrimination techniques and an argon scintillation veto, it is possible to suppress ^{42}K background by three orders of magnitude. This is sufficient for Phase II of the Gerda experiment.

  10. Environmental 222Rn as a background source in the solar neutrino experiment GALLEX

    International Nuclear Information System (INIS)

    Wojcik, M.

    1996-01-01

    The radiochemical neutrino experiment GALLEX is described. Its aim is to measure the flux of low energy solar neutrinos. In this experiment it is essential to suppress strongly the background of environmental origin, like charged cosmic rays, neutrons and gamma rays. In low-level radioactivity measurements performed in deep underground laboratory where flux of charged comic rays is strongly reduced, radon (Rn) exhaled from rock or concrete walls forms a most important strong, time-dependent background component. In this work the impact of Rn on the GALLEX experiment has been discussed and attempts to recognize and minimize its influence on the counter background were described. 63 refs, 22 figs, 11 tabs

  11. Environmental {sup 222}Rn as a background source in the solar neutrino experiment GALLEX

    Energy Technology Data Exchange (ETDEWEB)

    Wojcik, M. [Uniwersytet Jagiellonski, Cracow (Poland). Inst. Fizyki; BOREXINO

    1996-12-31

    The radiochemical neutrino experiment GALLEX is described. Its aim is to measure the flux of low energy solar neutrinos. In this experiment it is essential to suppress strongly the background of environmental origin, like charged cosmic rays, neutrons and gamma rays. In low-level radioactivity measurements performed in deep underground laboratory where flux of charged comic rays is strongly reduced, radon (Rn) exhaled from rock or concrete walls forms a most important strong, time-dependent background component. In this work the impact of Rn on the GALLEX experiment has been discussed and attempts to recognize and minimize its influence on the counter background were described. 63 refs, 22 figs, 11 tabs.

  12. Environmental {sup 222}Rn as a background source in the solar neutrino experiment GALLEX

    Energy Technology Data Exchange (ETDEWEB)

    Wojcik, M [Uniwersytet Jagiellonski, Cracow (Poland). Inst. Fizyki; BOREXINO,

    1997-12-31

    The radiochemical neutrino experiment GALLEX is described. Its aim is to measure the flux of low energy solar neutrinos. In this experiment it is essential to suppress strongly the background of environmental origin, like charged cosmic rays, neutrons and gamma rays. In low-level radioactivity measurements performed in deep underground laboratory where flux of charged comic rays is strongly reduced, radon (Rn) exhaled from rock or concrete walls forms a most important strong, time-dependent background component. In this work the impact of Rn on the GALLEX experiment has been discussed and attempts to recognize and minimize its influence on the counter background were described. 63 refs, 22 figs, 11 tabs.

  13. Kinetics experiments and bench-scale system: Background, design, and preliminary experiments

    International Nuclear Information System (INIS)

    Rofer, C.K.

    1987-10-01

    The project, Supercritical Water Oxidation of Hazardous Chemical Waste, is a Hazardous Waste Remedial Actions Program (HAZWRAP) Research and Development task being carried out by the Los Alamos National Laboratory. Its objective is to obtain information for use in understanding the basic technology and for scaling up and applying oxidation in supercritical water as a viable process for treating a variety of DOE-DP waste streams. This report gives the background and rationale for kinetics experiments on oxidation in supercritical water being carried out as a part of this HAZWRAP Research and Development task. It discusses supercritical fluid properties and their relevance to applying this process to the destruction of hazardous wastes. An overview is given of the small emerging industry based on applications of supercritical water oxidation. Factors that could lead to additional applications are listed. Modeling studies are described as a basis for the experimental design. The report describes plug flow reactor and batch reactor systems, and presents preliminary results. 28 refs., 4 figs., 5 tabs

  14. The Cosmic Background Explorer

    Science.gov (United States)

    Gulkis, Samuel; Lubin, Philip M.; Meyer, Stephan S.; Silverberg, Robert F.

    1990-01-01

    The Cosmic Background Explorer (CBE), NASA's cosmological satellite which will observe a radiative relic of the big bang, is discussed. The major questions connected to the big bang theory which may be clarified using the CBE are reviewed. The satellite instruments and experiments are described, including the Differential Microwave Radiometer, which measures the difference between microwave radiation emitted from two points on the sky, the Far-Infrared Absolute Spectrophotometer, which compares the spectrum of radiation from the sky at wavelengths from 100 microns to one cm with that from an internal blackbody, and the Diffuse Infrared Background Experiment, which searches for the radiation from the earliest generation of stars.

  15. Neutron lifetime experiments using magnetically trapped neutrons: optimal background correction strategies

    International Nuclear Information System (INIS)

    Coakley, K.J.

    2001-01-01

    In the first stage of each run of a neutron lifetime experiment, a magnetic trap is filled with neutrons. In the second stage of each run, decay events plus background events are observed. In a separate experiment, background is measured. The mean lifetime is estimated by fitting a two parameter exponential model to the background-corrected data. For two models of the background signal, I determine the optimal ratio of the number of 'background-only' measurements to the number of primary 'neutron decay plus background' measurements. Further, for each run, I determine the optimal allocation of time for filling and for observing decay events. For the case where the background consists of an activated material (aluminum) plus a stationary Poisson process, the asymptotic standard error of the lifetime estimate computed from the background-corrected data is lower than the asymptotic standard error computed from the uncorrected data. For the case where the background is a stationary Poisson process, background correction is desirable provided that the background intensity is sufficiently small compared to the rate at which neutrons enter the trap

  16. HerMES: The contribution to the cosmic infrared background from galaxies selected by mass and redshift

    Energy Technology Data Exchange (ETDEWEB)

    Viero, M. P.; Moncelsi, L.; Bock, J.; Bridge, C.; Cooray, A. [California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Quadri, R. F. [Carnegie Observatories, Pasadena, CA 91101 (United States); Arumugam, V.; Ivison, R. J. [Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); Assef, R. J. [Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Béthermin, M. [Laboratoire AIM-Paris-Saclay, CEA/DSM/Irfu-CNRS-Université Paris Diderot, CE-Saclay, pt courrier 131, F-91191 Gif-sur-Yvette (France); Casey, C. M. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Conley, A.; Glenn, J. [Center for Astrophysics and Space Astronomy 389-UCB, University of Colorado, Boulder, CO 80309 (United States); Farrah, D. [Department of Physics, Virginia Tech, Blacksburg, VA 24061 (United States); Heinis, S. [Laboratoire d' Astrophysique de Marseille-LAM, Université d' Aix-Marseille and CNRS, UMR7326, 38 rue F. Joliot-Curie, F-13388 Marseille Cedex 13 (France); Ibar, E. [Departamento de Astronomía y Astrofísica, Pontificia Universidad Catolica de Chile, Vicuña Mackenna 4860, Casilla 306, Santiago 22 (Chile); Ikarashi, S.; Kohno, K. [Institute of Astronomy, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Marsden, G. [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada); Oliver, S. J., E-mail: marco.viero@caltech.edu [Astronomy Centre, Department of Physics and Astronomy, University of Sussex, Brighton BN1 9QH (United Kingdom); and others

    2013-12-10

    We quantify the fraction of the cosmic infrared background (CIB) that originates from galaxies identified in the UV/optical/near-infrared by stacking 81,250 (∼35.7 arcmin{sup –2}) K-selected sources (K {sub AB} < 24.0) split according to their rest-frame U – V versus V – J colors into 72,216 star-forming and 9034 quiescent galaxies, on maps from Spitzer/MIPS (24 μm), Herschel/PACS (100, 160 μm), Herschel/SPIRE (250, 350, 500 μm), and AzTEC (1100 μm). The fraction of the CIB resolved by our catalog is (69% ± 15%) at 24 μm, (78% ± 17%) at 70 μm, (58% ± 13%) at 100 μm, (78% ± 18%) at 160 μm, (80% ± 17%) at 250 μm, (69% ± 14%) at 350 μm, (65% ± 12%) at 500 μm, and (45% ± 8%) at 1100 μm. Of that total, about 95% originates from star-forming galaxies, while the remaining 5% is from apparently quiescent galaxies. The CIB at λ ≲ 200 μm appears to be sourced predominantly from galaxies at z ≲ 1, while at λ ≳ 200 μm the bulk originates from 1 ≲ z ≲ 2. Galaxies with stellar masses log(M/M {sub ☉}) = 9.5-11 are responsible for the majority of the CIB, with those in the log(M/M {sub ☉}) = 9.5-10 bin contributing mostly at λ < 250 μm, and those in the log(M/M {sub ☉}) = 10-11 bin dominating at λ > 350 μm. The contribution from galaxies in the log(M/M {sub ☉}) = 9.0-9.5 (lowest) and log(M/M {sub ☉}) = 11.0-12.0 (highest) stellar-mass bins contribute the least—both of order 5%—although the highest stellar-mass bin is a significant contributor to the luminosity density at z ≳ 2. The luminosities of the galaxies responsible for the CIB shifts from combinations of 'normal' and luminous infrared galaxies (LIRGs) at λ ≲ 160 μm, to LIRGs at 160 ≲ λ ≲ 500 μm, to finally LIRGs and ultra-luminous infrared galaxies at λ ≳ 500 μm. Stacking analyses were performed using SIMSTACK, a novel algorithm designed to account for possible biases in the stacked flux density due to clustering. It is made available to

  17. Applying Bayesian neural networks to separate neutrino events from backgrounds in reactor neutrino experiments

    International Nuclear Information System (INIS)

    Xu, Y; Meng, Y X; Xu, W W

    2008-01-01

    A toy detector has been designed to simulate central detectors in reactor neutrino experiments in the paper. The samples of neutrino events and three major backgrounds from the Monte-Carlo simulation of the toy detector are generated in the signal region. The Bayesian Neural Networks (BNN) are applied to separate neutrino events from backgrounds in reactor neutrino experiments. As a result, the most neutrino events and uncorrelated background events in the signal region can be identified with BNN, and the part events each of the fast neutron and 8 He/ 9 Li backgrounds in the signal region can be identified with BNN. Then, the signal to noise ratio in the signal region is enhanced with BNN. The neutrino discrimination increases with the increase of the neutrino rate in the training sample. However, the background discriminations decrease with the decrease of the background rate in the training sample

  18. CRYSTALLIZATION EXPERIMENTS ON AMORPHOUS MAGNESIUM SILICATE. II. EFFECT OF STACKING FAULTS ON INFRARED SPECTRA OF ENSTATITE

    International Nuclear Information System (INIS)

    Murata, K.; Chihara, H.; Koike, C.; Takakura, T.; Imai, Y.; Tsuchiyama, A.; Noguchi, T.

    2009-01-01

    We carried out experiments of low-temperature infrared spectroscopy and transmission electron microscopy of enstatite (MgSiO 3 ) synthesized by heating of amorphous magnesium silicate. There is a discrepancy between the infrared feature of enstatite obtained in this experiment and that of fine powdered single crystals. This reflects stacking disorder of enstatite. We show that circumstellar dust emission of enstatite is similar to the infrared feature measured in this experiment. This result strongly suggests that circumstellar enstatite has abundant stacking faults and is different from the single crystal.

  19. Focal plane array based infrared thermography in fine physical experiment

    International Nuclear Information System (INIS)

    Vainer, Boris G

    2008-01-01

    By two examples of dissimilar physical phenomena causing thermophysical effects, the unique capabilities of one of the up-to-date methods of experimental physics-focal plane array (FPA) based infrared (IR) thermography (IRT), are demonstrated distinctly. Experimenters inexperienced in IRT can grasp how this method provides a means for combining real-time visualization with quantitative analysis. A narrow-band short-wavelength IR camera was used in the experiments. It is discussed and stated that IRT is best matched and suited to the next two test conditions-when a heated specimen is thin and when heat is generated in the immediate region of a surface of a solid. The first prerequisite is realized in the search for directional patterns of combined low-power radiation sources with the use of the IRT-aided method. The second one is realized in studies of water vapour adsorption on uneven (irregular) surfaces of solid materials. With multiple swatches taken from a set of different fabrics and used as experimental samples, a sharp distinction between adsorptivities of their surfaces is strikingly illustrated by IRT time-domain measurements exhibiting the associated thermal effect ranging within an order of magnitude. It is justified that the described IRT-aided test can find practical implementation at least in the light industry. Emissivities of different fabrics are evaluated experimentally with the described reflection method based on the narrow spectral range of IRT. On the basis of direct IR observations, attention is paid to the need for close control over the surface temperature increase while the adsorption isotherms are being measured. Sensitivity of the FPA-based IRT method, as applied to examine the kinetics of initial stages of adsorption of gaseous molecules on the solid surface, is evaluated analytically and quantitatively. The relationship between the amount of adsorbate and the measurable excess of adsorbent temperature is found. It is discovered that

  20. GOODS-Herschel: identification of the individual galaxies responsible for the 80-290 μm cosmic infrared background

    Science.gov (United States)

    Leiton, R.; Elbaz, D.; Okumura, K.; Hwang, H. S.; Magdis, G.; Magnelli, B.; Valtchanov, I.; Dickinson, M.; Béthermin, M.; Schreiber, C.; Charmandaris, V.; Dole, H.; Juneau, S.; Le Borgne, D.; Pannella, M.; Pope, A.; Popesso, P.

    2015-07-01

    Aims: We propose a new method of pushing Herschel to its faintest detection limits using universal trends in the redshift evolution of the far infrared over 24 μm colours in the well-sampled GOODS-North field. An extension to other fields with less multi-wavelength information is presented. This method is applied here to raise the contribution of individually detected Herschel sources to the cosmic infrared background (CIRB) by a factor 5 close to its peak at 250 μm and more than 3 in the 350 and 500 μm bands. Methods: We produce realistic mock Herschel images of the deep PACS and SPIRE images of the GOODS-North field from the GOODS-Herschel key program and use them to quantify the confusion noise at the position of individual sources, i.e., estimate a "local confusion noise". Two methods are used to identify sources with reliable photometric accuracy extracted using 24 μm prior positions. The clean index (CI), previously defined but validated here with simulations, which measures the presence of bright 24 μm neighbours and the photometric accuracy index (PAI) directly extracted from the mock Herschel images. Results: Both methods converge to comparable depths and fractions of the CIRB resolved into sources individually detected with Herschel. After correction for completeness, thanks to our mock Herschel images, individually detected sources make up as much as 54% and 60% of the CIRB in the PACS bands down to 1.1 mJy at 100 μm and 2.2 mJy at 160 μm and 55, 33, and 13% of the CIRB in the SPIRE bands down to 2.5, 5, and 9 mJy at 250 μm, 350 μm, and 500 μm, respectively. The latter depths improve the detection limits of Herschel by factors of 5 at 250 μm, and 3 at 350 μm and 500 μm as compared to the standard confusion limit. Interestingly, the dominant contributors to the CIRB in all Herschel bands appear to be distant siblings of the Milky Way (z ~ 0.96 for λ< 300 μm) with a stellar mass of M⋆ ~ 9 × 1010M⊙.

  1. The Limb Infrared Monitor of the Stratosphere (LIMS) experiment

    Science.gov (United States)

    Russell, J. M.; Gille, J. C.

    1978-01-01

    The Limb Infrared Monitor of the Stratosphere is used to obtain vertical profiles and maps of temperature and the concentration of ozone, water vapor, nitrogen dioxide, and nitric acid for the region of the stratosphere bounded by the upper troposphere and the lower mesosphere.

  2. Background determination for the neutron-neutron scattering experiment at the reactor YAGUAR

    Energy Technology Data Exchange (ETDEWEB)

    Muzichka, A.Yu. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Furman, W.I. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Lychagin, E.V. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Krylov, A.R. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Nekhaev, G.V. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Sharapov, E.I. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Shvetsov, V.N. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Strelkov, A.V. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Levakov, B.G. [Russian Federal Nuclear Center-All-Russian Research Institute of Technical Physics, PO Box 245, 456770 Snezhinsk (Russian Federation); Lyzhin, A.E. [Russian Federal Nuclear Center-All-Russian Research Institute of Technical Physics, PO Box 245, 456770 Snezhinsk (Russian Federation); Chernukhin, Yu.I. [Russian Federal Nuclear Center-All-Russian Research Institute of Technical Physics, PO Box 245, 456770 Snezhinsk (Russian Federation); Kandiev, Ya.Z. [Russian Federal Nuclear Center-All-Russian Research Institute of Technical Physics, PO Box 245, 456770 Snezhinsk (Russian Federation); Howell, C.R. [Duke University and Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States); Mitchell, G.E. [North Carolina State University, Raleigh, NC 27695-8202 (United States); Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States); Crawford, B.E. [Gettysburg College, Box 405, Gettysburg, PA 17325 (United States); Stephenson, S.L. [Gettysburg College, Box 405, Gettysburg, PA 17325 (United States)]. E-mail: sstephen@gettysburg.edu; Tornow, W. [Duke University and Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States)

    2007-06-01

    The motivation and design is outlined for the experiment to measure the neutron-neutron singlet scattering length directly with thermal neutrons at the pulsed reactor YAGUAR. A statistical accuracy of 3% can be reached, though achieving the goal of an overall accuracy of 3-5% for the nn-scattering length depends on the background level. Possible sources of background are discussed in depth and the results of extensive modeling of the background are presented. Measurements performed at YAGUAR to test these background calculations are described. The experimental results indicate an anticipated background level up to 30% relative to the expected nn effect at the maximal energy burst of the reactor. The conclusion is made that the nn experiment at YAGUAR is feasible to produce the first directly measured value for the neutron-neutron scattering length.

  3. Infrared

    Science.gov (United States)

    Vollmer, M.

    2013-11-01

    'Infrared' is a very wide field in physics and the natural sciences which has evolved enormously in recent decades. It all started in 1800 with Friedrich Wilhelm Herschel's discovery of infrared (IR) radiation within the spectrum of the Sun. Thereafter a few important milestones towards widespread use of IR were the quantitative description of the laws of blackbody radiation by Max Planck in 1900; the application of quantum mechanics to understand the rotational-vibrational spectra of molecules starting in the first half of the 20th century; and the revolution in source and detector technologies due to micro-technological breakthroughs towards the end of the 20th century. This has led to much high-quality and sophisticated equipment in terms of detectors, sources and instruments in the IR spectral range, with a multitude of different applications in science and technology. This special issue tries to focus on a few aspects of the astonishing variety of different disciplines, techniques and applications concerning the general topic of infrared radiation. Part of the content is based upon an interdisciplinary international conference on the topic held in 2012 in Bad Honnef, Germany. It is hoped that the information provided here may be useful for teaching the general topic of electromagnetic radiation in the IR spectral range in advanced university courses for postgraduate students. In the most general terms, the infrared spectral range is defined to extend from wavelengths of 780 nm (upper range of the VIS spectral range) up to wavelengths of 1 mm (lower end of the microwave range). Various definitions of near, middle and far infrared or thermal infrared, and lately terahertz frequencies, are used, which all fall in this range. These special definitions often depend on the scientific field of research. Unfortunately, many of these fields seem to have developed independently from neighbouring disciplines, although they deal with very similar topics in respect of the

  4. Background and technical studies for GENIUS as a dark matter experiment

    International Nuclear Information System (INIS)

    Baudis, L.; Heusser, G.; Majorovits, B.; Ramachers, Y.; Strecker, H.; Klapdor-Kleingrothaus, H.V.

    1999-01-01

    The GENIUS project is a proposal for a new dark matter detector, with an increased sensitivity of three orders of magnitude relative to existing direct dark matter detection experiments. We performed a technical study and calculated the main background sources for the relevant energy region in a detailed detector geometry. The achieved overall background level and detector performance confirm the outstanding potential of GENIUS as a powerful tool for the direct search of WIMPs in our Galaxy

  5. Upper limits of a cosmic infrared background flux as determined by X- and gamma-ray observations on M87

    International Nuclear Information System (INIS)

    Schlickeiser, R.; Cambridge Univ.; Harwit, M.; Cornell Univ., Ithaca, NY

    1982-01-01

    Upper limits on the energy density of infrared photons in the radio lobe regions of M87 are derived using measurements of the X-ray and gamma-ray emission. The calculations are based on an inverse Compton scattering model initiated by radio-flux producing electrons. It is shown that the energy density of infrared photons in the radio lobe regions is similar than 2 eV cm -3 . (orig.)

  6. Mitigation of {sup 42}Ar/{sup 42}K background for the GERDA Phase II experiment

    Energy Technology Data Exchange (ETDEWEB)

    Lubashevskiy, A.; Klimenko, A.; Smolnikov, A. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Joint Institute for Nuclear Research, Dubna (Russian Federation); Agostini, M. [Gran Sasso Science Institute, L' Aquila (Italy); Budjas, D.; Lazzaro, A.; Schoenert, S. [Technische Universitaet Muenchen, Physik Department E15, Munich (Germany); Gangapshev, A. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Institute for Nuclear Research, Russian Academy of Sciences, Moscow (Russian Federation); Gusev, K. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Technische Universitaet Muenchen, Physik Department E15, Munich (Germany); Russian Research Center Kurchatov Institute, Moscow (Russian Federation); Heisel, M. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Lehnert, B. [Institut fuer Kern- und Teilchenphysik Technische Universitaet Dresden, Dresden (Germany); Carleton University, Physics Department, Ottawa (Canada); Pelczar, K. [Jagellonian University, Institute of Physics, Cracow (Poland); INFN Laboratori Nazionali del Gran Sasso, LNGS, Assergi (Italy); Walter, M. [Physik Institut der Universitaet Zuerich, Zurich (Switzerland); Zuzel, G. [Jagellonian University, Institute of Physics, Cracow (Poland)

    2018-01-15

    Background coming from the {sup 42}Ar decay chain is considered to be one of the most relevant for the Gerda experiment, which searches for the neutrinoless double beta decay of {sup 76}Ge. The sensitivity strongly relies on the absence of background around the Q-value of the decay. Background coming from {sup 42}K, a progeny of {sup 42}Ar, can contribute to that background via electrons from the continuous spectrum with an endpoint at 3.5 MeV. Research and development on the suppression methods targeting this source of background were performed at the low-background test facility LArGe. It was demonstrated that by reducing {sup 42}K ion collection on the surfaces of the broad energy germanium detectors in combination with pulse shape discrimination techniques and an argon scintillation veto, it is possible to suppress {sup 42}K background by three orders of magnitude. This is sufficient for Phase II of the Gerda experiment. (orig.)

  7. Background study of absorbed dose in biological experiments at the Modane Underground Laboratory

    Directory of Open Access Journals (Sweden)

    Lampe Nathanael

    2016-01-01

    Full Text Available Aiming to explore how biological systems respond to ultra-low background environ-ments, we report here our background studies for biological experiments in the Modane Under-ground Laboratory. We find that the minimum radioactive background for biology experiments is limited by the potassium content of the biological sample itself, coming from its nutritive me-dium, which we find in our experimental set-up to be 26 nGy hr-1. Compared to our reference radiation environment in Clermont-Ferrand, biological experiments can be conducted in the Modane laboratory with a radiation background 8.2 times lower than the reference above-ground level. As the radiation background may be further reduced by using different nutritive media, we also provide measurements of the potassium concentration by gamma spectroscopy of yeast extract (63.3±1.2 mg g-1 and tryptone (2.5±0.2 mg g-1 in order to guide media selection in future experiments.

  8. RESOLVING THE COSMIC FAR-INFRARED BACKGROUND AT 450 AND 850 μm WITH SCUBA-2

    International Nuclear Information System (INIS)

    Chen, Chian-Chou; Cowie, Lennox L.; Barger, Amy J.; Casey, Caitlin M.; Lee, Nicholas; Sanders, David B.; Williams, Jonathan P.; Wang, Wei-Hao

    2013-01-01

    We use the SCUBA-2 submillimeter camera mounted on the James Clerk Maxwell Telescope to obtain extremely deep number counts at 450 and 850 μm. We combine data on two cluster lensing fields, A1689 and A370, and three blank fields, CDF-N, CDF-S, and COSMOS, to measure the counts over a wide flux range at each wavelength. We use statistical fits to broken power law representations to determine the number counts. This allows us to probe to the deepest possible level in the data. At both wavelengths our results agree well with the literature in the flux range over which they have been measured, with the exception of the 850 μm counts in CDF-S, where we do not observe the counts deficit found by previous single-dish observations. At 450 μm, we detect significant counts down to ∼1 mJy, an unprecedented depth at this wavelength. By integrating the number counts above this flux limit, we measure 113.9 +49.7 -28.4 Jy deg –2 of the 450 μm extragalactic background light (EBL). The majority of this contribution is from sources with S 450 μ m between 1-10 mJy, and these sources are likely to be the ones that are analogous to the local luminous infrared galaxies. At 850 μm, we measure 37.3 +21.1 -12.9 Jy deg –2 of the EBL. Because of the large systematic uncertainties on the COBE measurements, the percentage of the EBL we resolve could range from 48%-153% (44%-178%) at 450 (850) μm. Based on high-resolution Submillimeter Array observations of around half of the 4 σ 850 μm sample in CDF-N, we find that 12.5 +12.1 -6.8 % of the sources are blends of multiple fainter sources. This is a low multiple fraction, and we find no significant difference between our original SCUBA-2 850 μm counts and the multiplicity-corrected counts

  9. Resolving the Cosmic Far-infrared Background at 450 and 850 μm with SCUBA-2

    Science.gov (United States)

    Chen, Chian-Chou; Cowie, Lennox L.; Barger, Amy J.; Casey, Caitlin. M.; Lee, Nicholas; Sanders, David B.; Wang, Wei-Hao; Williams, Jonathan P.

    2013-10-01

    We use the SCUBA-2 submillimeter camera mounted on the James Clerk Maxwell Telescope to obtain extremely deep number counts at 450 and 850 μm. We combine data on two cluster lensing fields, A1689 and A370, and three blank fields, CDF-N, CDF-S, and COSMOS, to measure the counts over a wide flux range at each wavelength. We use statistical fits to broken power law representations to determine the number counts. This allows us to probe to the deepest possible level in the data. At both wavelengths our results agree well with the literature in the flux range over which they have been measured, with the exception of the 850 μm counts in CDF-S, where we do not observe the counts deficit found by previous single-dish observations. At 450 μm, we detect significant counts down to ~1 mJy, an unprecedented depth at this wavelength. By integrating the number counts above this flux limit, we measure 113.9^{+49.7}_{-28.4} Jy deg-2 of the 450 μm extragalactic background light (EBL). The majority of this contribution is from sources with S 450 μm between 1-10 mJy, and these sources are likely to be the ones that are analogous to the local luminous infrared galaxies. At 850 μm, we measure 37.3^{+21.1}_{-12.9} Jy deg-2 of the EBL. Because of the large systematic uncertainties on the COBE measurements, the percentage of the EBL we resolve could range from 48%-153% (44%-178%) at 450 (850) μm. Based on high-resolution Submillimeter Array observations of around half of the 4 σ 850 μm sample in CDF-N, we find that 12.5^{ +12.1}_{ -6.8}% of the sources are blends of multiple fainter sources. This is a low multiple fraction, and we find no significant difference between our original SCUBA-2 850 μm counts and the multiplicity-corrected counts.

  10. The MAJORANA experiment: an ultra-low background search for neutrinoless double-beta decay

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, D.; Aguayo Navarrete, Estanislao; Avignone, Frank T.; Back, Henning O.; Barabash, Alexander S.; Bergevin, M.; Bertrand, F.; Boswell, M.; Brudanin, V.; Busch, Matthew; Chan, Yuen-Dat; Christofferson, Cabot-Ann; Collar, J. I.; Combs, Dustin C.; Cooper, R. J.; Detwiler, Jason A.; Doe, Peter J.; Efremenko, Yuri; Egorov, Viatcheslav; Ejiri, H.; Elliott, Steven R.; Esterline, James H.; Fast, James E.; Fields, N.; Finnerty, P.; Fraenkle, Florian; Gehman, Victor; Giovanetti, G. K.; Green, Matthew P.; Guiseppe, Vincente; Gusey, K.; Hallin, A. L.; Hazama, R.; Henning, Reyco; Hime, Andrew; Hoppe, Eric W.; Horton, Mark; Howard, Stanley; Howe, M. A.; Johnson, R. A.; Keeter, K.; Keller, C.; Kidd, Mary; Knecht, A.; Kochetov, Oleg; Konovalov, S.; Kouzes, Richard T.; LaFerriere, Brian D.; LaRoque, B. H.; Leon, Jonathan D.; Leviner, L.; Loach, J. C.; MacMullin, S.; Marino, Michael G.; Martin, R. D.; Mei, Dong-Ming; Merriman, Jason H.; Miller, M. L.; Mizouni, Leila; Nomachi, Masaharu; Orrell, John L.; Overman, Nicole R.; Poon, Alan; Perumpilly, Gopakumar; Prior, Gersende; Radford, D. C.; Rielage, Keith; Robertson, R. G. H.; Ronquest, M. C.; Schubert, Alexis G.; Shima, T.; Shirchenko, M.; Snavely, Kyle J.; Steele, David; Strain, J.; Thomas, K.; Timkin, V.; Tornow, W.; Vanyushin, I.; Varner, R. L.; Vetter, Kai; Vorren, Kris R.; Wilkerson, J. F.; Wolfe, B. A.; Yakushev, E.; Young, A.; Yu, Chang-Hong; Yumatov, Vladimir; Zhang, C.

    2012-12-01

    The observation of neutrinoless double-beta decay would resolve the Majorana nature of the neutrino and could provide information on the absolute scale of the neutrino mass. The initial phase of the Majorana Experiment, known as the Demonstrator, will house 40 kg of Ge in an ultra-low background shielded environment at the 4850' level of the Sanford Underground Laboratory in Lead, SD. The objective of the Demonstrator is to validate whether a future 1-tonne experiment can achieve a background goal of one count per tonne-year in a narrow region of interest around the 76Ge neutrinoless double-beta decay peak.

  11. Monte Carlo-based development of a shield and total background estimation for the COBRA experiment

    International Nuclear Information System (INIS)

    Heidrich, Nadine

    2014-11-01

    The COBRA experiment aims for the measurement of the neutrinoless double beta decay and thus for the determination the effective Majorana mass of the neutrino. To be competitive with other next-generation experiments the background rate has to be in the order of 10 -3 counts/kg/keV/yr, which is a challenging criterion. This thesis deals with the development of a shield design and the calculation of the expected total background rate for the large scale COBRA experiment containing 13824 6 cm 3 CdZnTe detectors. For the development of a shield single-layer and multi-layer shields were investigated and a shield design was optimized concerning high-energy muon-induced neutrons. As the best design the combination of 10 cm boron doped polyethylene as outermost layer, 20 cm lead and 10 cm copper as innermost layer were determined. It showed the best performance regarding neutron attenuation as well as (n, γ) self-shielding effects leading to a negligible background rate of less than 2.10 -6 counts/kg/keV/yr. Additionally. the shield with a thickness of 40 cm is compact and costeffective. In the next step the expected total background rate was computed taking into account individual setup parts and various background sources including natural and man-made radioactivity, cosmic ray-induced background and thermal neutrons. Furthermore, a comparison of measured data from the COBRA demonstrator setup with Monte Carlo data was used to calculate reliable contamination levels of the single setup parts. The calculation was performed conservatively to prevent an underestimation. In addition, the contribution to the total background rate regarding the individual detector parts and background sources was investigated. The main portion arise from the Delrin support structure, the Glyptal lacquer followed by the circuit board of the high voltage supply. Most background events originate from particles with a quantity of 99 % in total. Regarding surface events a contribution of 26

  12. Monte Carlo-based development of a shield and total background estimation for the COBRA experiment

    Energy Technology Data Exchange (ETDEWEB)

    Heidrich, Nadine

    2014-11-15

    The COBRA experiment aims for the measurement of the neutrinoless double beta decay and thus for the determination the effective Majorana mass of the neutrino. To be competitive with other next-generation experiments the background rate has to be in the order of 10{sup -3} counts/kg/keV/yr, which is a challenging criterion. This thesis deals with the development of a shield design and the calculation of the expected total background rate for the large scale COBRA experiment containing 13824 6 cm{sup 3} CdZnTe detectors. For the development of a shield single-layer and multi-layer shields were investigated and a shield design was optimized concerning high-energy muon-induced neutrons. As the best design the combination of 10 cm boron doped polyethylene as outermost layer, 20 cm lead and 10 cm copper as innermost layer were determined. It showed the best performance regarding neutron attenuation as well as (n, γ) self-shielding effects leading to a negligible background rate of less than 2.10{sup -6} counts/kg/keV/yr. Additionally. the shield with a thickness of 40 cm is compact and costeffective. In the next step the expected total background rate was computed taking into account individual setup parts and various background sources including natural and man-made radioactivity, cosmic ray-induced background and thermal neutrons. Furthermore, a comparison of measured data from the COBRA demonstrator setup with Monte Carlo data was used to calculate reliable contamination levels of the single setup parts. The calculation was performed conservatively to prevent an underestimation. In addition, the contribution to the total background rate regarding the individual detector parts and background sources was investigated. The main portion arise from the Delrin support structure, the Glyptal lacquer followed by the circuit board of the high voltage supply. Most background events originate from particles with a quantity of 99 % in total. Regarding surface events a

  13. Students' Moral Reasoning as Related to Cultural Background and Educational Experience.

    Science.gov (United States)

    Bar-Yam, Miriam; And Others

    The relationship between moral development and cultural and educational background is examined. Approximately 120 Israeli youth representing different social classes, sex, religious affiliation, and educational experience were interviewed. The youth interviewed included urban middle and lower class students, Kibbutz-born, Youth Aliyah…

  14. The background of external γ radiation in the proportional counters in SAGE experiment

    International Nuclear Information System (INIS)

    Gavrin, V.N.; Gorbachev, V.V.

    2003-01-01

    The influence of external γ radiation on the process of 71 Ge-decay counting in proportional counters in SAGE experiment of solar neutrino flux measurement is examined. One determines the systematic error of SAGE result, connected with radon decays inside the air volume surrounding the counters, and the background counting rate of proportional counters from γ radiation of passive and active shield [ru

  15. Input comparison of radiogenic neutron estimates for ultra-low background experiments

    Science.gov (United States)

    Cooley, J.; Palladino, K. J.; Qiu, H.; Selvi, M.; Scorza, S.; Zhang, C.

    2018-04-01

    Ultra-low-background experiments address some of the most important open questions in particle physics, cosmology and astrophysics: the nature of dark matter, whether the neutrino is its own antiparticle, and does the proton decay. These rare event searches require well-understood and minimized backgrounds. Simulations are used to understand backgrounds caused by naturally occurring radioactivity in the rock and in every piece of shielding and detector material used in these experiments. Most important are processes like spontaneous fission and (α,n) reactions in material close to the detectors that can produce neutrons. A comparison study of the (α,n) reactions between two dedicated software packages is detailed. The cross section libraries, neutron yields, and spectra from the Mei-Zhang-Hime and the SOURCES-4A codes are presented. The resultant yields and spectra are used as inputs to direct dark matter detector toy models in GEANT4, to study the impact of their differences on background estimates and fits. Although differences in neutron yield calculations up to 50% were seen, there was no systematic difference between the Mei-Hime-Zhang and SOURCES-4A results. Neutron propagation simulations smooth differences in spectral shape and yield, and both tools were found to meet the broad requirements of the low-background community.

  16. Screening experiments of ecstasy street samples using near infrared spectroscopy.

    Science.gov (United States)

    Sondermann, N; Kovar, K A

    1999-12-20

    Twelve different sets of confiscated ecstasy samples were analysed applying both near infrared spectroscopy in reflectance mode (1100-2500 nm) and high-performance liquid chromatography (HPLC). The sets showed a large variance in composition. A calibration data set was generated based on the theory of factorial designs. It contained 221 N-methyl-3,4-methylenedioxyamphetamine (MDMA) samples, 167 N-ethyl-3,4-methylenedioxyamphetamine (MDE), 111 amphetamine and 106 samples without a controlled substance, which will be called placebo samples thereafter. From this data set, PLS-1 models were calculated and were successfully applied for validation of various external laboratory test sets. The transferability of these results to confiscated tablets is demonstrated here. It is shown that differentiation into placebo, amphetamine and ecstasy samples is possible. Analysis of intact tablets is practicable. However, more reliable results are obtained from pulverised samples. This is due to ill-defined production procedures. The use of mathematically pretreated spectra improves the prediction quality of all the PLS-1 models studied. It is possible to improve discrimination between MDE and MDMA with the help of a second model based on raw spectra. Alternative strategies are briefly discussed.

  17. Suppression of the background coming from {sup 42}Ar in the GERDA experiment

    Energy Technology Data Exchange (ETDEWEB)

    Lubashevskiy, Alexey [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Collaboration: GERDA-Collaboration

    2016-07-01

    The GERDA experiment aims at the 0νββ search in {sup 76}Ge. The search is performed with high purity germanium detectors operated in liquid argon. One of the most dangerous backgrounds in GERDA is the background from {sup 42}K which is a daughter isotope of cosmogenically produced {sup 42}Ar, presented in natural argon. {sup 42}K ions collect on the surface of the detector and increase its background level. Several ways to suppress such background has been investigated. The tests were performed at LArGe low-background test facility, which gives a possibility to operate bare detectors in about 1m{sup 3} of LAr. It is equipped with a scintillation veto, so particles which deposit part of their energy in LAr can be detected by PMTs. The experimental setup is located at LNGS underground laboratory close to GERDA experiment location. Different experimental techniques were tested together with pulse shape discrimination (PSD) method in order to suppress {sup 42}K background. The chosen solution for GERDA Phase II is so called ''nylon mini-shroud'' (NMS). It is made from nylon foil and covered with wavelength shifter from both sides. NMS allows to suppress collection of {sup 42}K ions towards to the surface significantly. It was demonstrated in LArGe that together with PSD and scintillation veto the {sup 42}K background can be suppressed in more than 1000 times. The results obtained during commissioning runs in GERDA Phase II are also presented.

  18. Numerical modeling of plasma plume evolution against ambient background gas in laser blow off experiments

    International Nuclear Information System (INIS)

    Patel, Bhavesh G.; Das, Amita; Kaw, Predhiman; Singh, Rajesh; Kumar, Ajai

    2012-01-01

    Two dimensional numerical modelling based on simplified hydrodynamic evolution for an expanding plasma plume (created by laser blow off) against an ambient background gas has been carried out. A comparison with experimental observations shows that these simulations capture most features of the plasma plume expansion. The plume location and other gross features are reproduced as per the experimental observation in quantitative detail. The plume shape evolution and its dependence on the ambient background gas are in good qualitative agreement with the experiment. This suggests that a simplified hydrodynamic expansion model is adequate for the description of plasma plume expansion.

  19. Evaluation of childhood trauma with respect to criminal behavior, dissociative experiences, adverse family experiences and psychiatric backgrounds among prison inmates.

    Science.gov (United States)

    Altintas, Merih; Bilici, Mustafa

    2018-04-01

    To evaluate childhood trauma in relation to criminal behavior, dissociative experiences, adverse family experiences during childhood and psychiatric backgrounds among prison inmates. In total, 200 prison inmates were included in this questionnaire-based study. Data on demographic characteristics, adverse family experiences during childhood and psychiatric backgrounds were collected via face-to-face interviews, and a psychometric evaluation was conducted using the Childhood Trauma Questionnaire (CTQ-28) and Dissociative Experiences Scale (DES). Several historical items were more common in females than in males including family history of psychiatric disease (23.0% vs. 13.0%, p = 0.048), a personal history of psychiatric disease (51.0% vs. 29.0%, p first crime (24.9 ± 8.9 years vs. 30.3 ± 9.2 years, p first offense (β = 0.772, p first offense. In conclusion, our findings revealed a high prevalence of and significant associations among childhood trauma, dissociative experiences, adverse family experiences and psychiatric problems in a cohort of incarcerated females and males. A psychiatric background, childhood trauma characterized by sexual abuse and violent crimes were found to be predominant in female prison inmates, whereas a criminal background with a younger age at first offense and frequent previous convictions, substance use and sexual crimes were more prevalent among male prison inmates. Our findings indicate a potential link between childhood traumatization and criminal behavior in terms of subsequent offending but not in terms of severity of the subsequent offense. Copyright © 2018. Published by Elsevier Inc.

  20. High-speed infrared imaging for material characterization in experimental mechanics experiments

    Science.gov (United States)

    Gagnon, Marc-André; Marcotte, Frédérick; Lagueux, Philippe; Farley, Vincent; Guyot, Éric; Morton, Vince

    2017-10-01

    Heat transfers are involved in many phenomena such as friction, tensile stress, shear stress and material rupture. Among the challenges encountered during the characterization of such thermal patterns is the need for both high spatial and temporal resolution. Infrared imaging provides information about surface temperature that can be attributed to the stress response of the material and breaking of chemical bounds. In order to illustrate this concept, tensile and shear tests were carried out on steel, aluminum and carbon fiber composite materials and monitored using high-speed (Telops FASTM2K) and high-definition (Telops HD-IR) infrared imaging. Results from split-Hopkinson experiments carried out on a polymer material at high strain-rate are also presented. The results illustrate how high-speed and high-definition infrared imaging in the midwave infrared (MWIR, 3 - 5 μm) spectral range can provide detailed information about the thermal properties of materials undergoing mechanical testing.

  1. Background of external γ radiation in the proportional counters of the SAGE experiment

    International Nuclear Information System (INIS)

    Gavrin, V.N.; Gorbachev, V.V.

    2003-01-01

    The effect of external γ radiation on the process of counting 71 Ge decays in the proportional counters of the SAGE experiment measuring the solar-neutrino flux is considered. The systematic uncertainty in the SAGE result due to radon decays inside the air volume surrounding the counters is estimated. The background counting rate in the proportional counters that is caused by γ radiation from the enclosing shield is also determined

  2. Measurements of Plasma Expansion due to Background Gas in the Electron Diffusion Gauge Experiment

    International Nuclear Information System (INIS)

    Morrison, Kyle A.; Paul, Stephen F.; Davidson, Ronald C.

    2003-01-01

    The expansion of pure electron plasmas due to collisions with background neutral gas atoms in the Electron Diffusion Gauge (EDG) experiment device is observed. Measurements of plasma expansion with the new, phosphor-screen density diagnostic suggest that the expansion rates measured previously were observed during the plasma's relaxation to quasi-thermal-equilibrium, making it even more remarkable that they scale classically with pressure. Measurements of the on-axis, parallel plasma temperature evolution support the conclusion

  3. The background in the 0νββ experiment GERDA

    Energy Technology Data Exchange (ETDEWEB)

    Agostini, M.; Bode, T.; Budjas, D.; Csathy, J.J.; Lazzaro, A.; Schoenert, S. [Technische Universitaet Muenchen, Physik Department and Excellence Cluster Universe, Muenchen (Germany); Allardt, M.; Barros, N.; Domula, A.; Lehnert, B.; Wester, T.; Zuber, K. [Technische Universitaet Dresden, Institut fuer Kern- und Teilchenphysik, Dresden (Germany); Andreotti, E. [Institute for Reference Materials and Measurements, Geel (Belgium); Eberhard Karls Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); Bakalyarov, A.M.; Belyaev, S.T.; Lebedev, V.I.; Zhukov, S.V. [National Research Centre ' ' Kurchatov Institute' ' , Moscow (Russian Federation); Balata, M.; Ioannucci, L.; Junker, M.; Laubenstein, M.; Macolino, C.; Nisi, S.; Pandola, L.; Zavarise, P. [INFN Laboratori Nazionali del Gran Sasso, LNGS, Assergi (Italy); Barabanov, I.; Bezrukov, L.; Gurentsov, V.; Inzhechik, L.V.; Kuzminov, V.V.; Lubsandorzhiev, B.; Yanovich, E. [Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Barnabe Heider, M. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Technische Universitaet Muenchen, Physik Department and Excellence Cluster Universe, Muenchen (Germany); Baudis, L.; Benato, G.; Ferella, A.; Guthikonda, K.K.; Tarka, M.; Walter, M. [Physik Institut der Universitaet Zuerich, Zurich (Switzerland); Bauer, C.; Hampel, W.; Heisel, M.; Heusser, G.; Hofmann, W.; Kihm, T.; Kirsch, A.; Knoepfle, K.T.; Lindner, M.; Lubashevskiy, A.; Machado, A.A.; Maneschg, W.; Salathe, M.; Schreiner, J.; Schwingenheuer, B.; Simgen, H.; Smolnikov, A.; Strecker, H.; Wagner, V.; Wegmann, A. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Becerici-Schmidt, N.; Caldwell, A.; Cossavella, F.; Liao, H.Y.; Liu, X.; Majorovits, B.; O' Shaughnessy, C.; Palioselitis, D.; Schulz, O.; Volynets, O. [Max-Planck-Institut fuer Physik, Muenchen (Germany); Bellotti, E.; Pessina, G. [Universita Milano Bicocca, Dipartimento di Fisica, Milan (Italy); INFN Milano Bicocca, Milan (Italy); Belogurov, S.; Kornoukhov, V.N. [Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Bettini, A.; Brugnera, R.; Garfagnini, A.; Hemmer, S.; Sada, C. [Dipartimento di Fisica e Astronomia dell' Universita di Padova, Padua (Italy); INFN Padova, Padua (Italy); Brudanin, V.; Egorov, V.; Kochetov, O.; Nemchenok, I.; Shevchik, E.; Zhitnikov, I.; Zinatulina, D. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Cattadori, C.; Gotti, C. [INFN Milano Bicocca, Milan (Italy); Chernogorov, A.; Demidova, E.V.; Kirpichnikov, I.V.; Vasenko, A.A. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Falkenstein, R.; Freund, K.; Grabmayr, P.; Hegai, A.; Jochum, J.; Schmitt, C. [Eberhard Karls Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); Frodyma, N.; Pelczar, K.; Wojcik, M.; Zuzel, G. [Jagiellonian University, Institute of Physics, Cracow (Poland); Gangapshev, A. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Gusev, K. [Joint Institute for Nuclear Research, Dubna (Russian Federation); National Research Centre ' ' Kurchatov Institute' ' , Moscow (Russian Federation); Technische Universitaet Muenchen, Physik Department and Excellence Cluster Universe, Muenchen (Germany); Hult, M.; Lutter, G. [Institute for Reference Materials and Measurements, Geel (Belgium); Klimenko, A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Lippi, I.; Stanco, L.; Ur, C.A. [INFN Padova, Padua (Italy); Pullia, A.; Riboldi, S. [Universita degli Studi di Milano (IT); INFN Milano, Dipartimento di Fisica, Milan (IT); Shirchenko, M. [Joint Institute for Nuclear Research, Dubna (RU); National Research Centre ' ' Kurchatov Institute' ' , Moscow (RU); Sturm, K. von [Dipartimento di Fisica e Astronomia dell' Universita di Padova, Padua (IT); INFN Padova, Padua (IT); Eberhard Karls Universitaet Tuebingen, Physikalisches Institut, Tuebingen (DE)

    2014-04-15

    The GERmanium Detector Array (GERDA) experiment at the Gran Sasso underground laboratory (LNGS) of INFN is searching for neutrinoless double beta (0νββ) decay of {sup 76}Ge. The signature of the signal is a monoenergetic peak at 2039 keV, the Q{sub ββ} value of the decay. To avoid bias in the signal search, the present analysis does not consider all those events, that fall in a 40 keV wide region centered around Q{sub ββ}. The main parameters needed for the 0νββ analysis are described. A background model was developed to describe the observed energy spectrum. The model contains several contributions, that are expected on the basis of material screening or that are established by the observation of characteristic structures in the energy spectrum. The model predicts a flat energy spectrum for the blinding window around Q{sub ββ} with a background index ranging from 17.6 to 23.8 x 10{sup -3} cts/(keV kg yr). A part of the data not considered before has been used to test if the predictions of the background model are consistent. The observed number of events in this energy region is consistent with the background model. The background at Q{sub ββ} is dominated by close sources,mainly due to {sup 42}K, {sup 214}Bi, {sup 228}Th, {sup 60}Co and α emitting isotopes from the {sup 226}Ra decay chain. The individual fractions depend on the assumed locations of the contaminants. It is shown, that after removal of the known γ peaks, the energy spectrum can be fitted in an energy range of 200 keV around Q{sub ββ} with a constant background. This gives a background index consistent with the full model and uncertainties of the same size. (orig.)

  4. On-site underground background measurements for the KASKA reactor-neutrino experiment

    International Nuclear Information System (INIS)

    Furuta, H.; Sakuma, K.; Aoki, M.; Fukuda, Y.; Funaki, Y.; Hara, T.; Haruna, T.; Ishihara, N.; Katsumata, M.; Kawasaki, T.; Kuze, M.; Maeda, J.; Matsubara, T.; Matsumoto, T.; Miyata, H.; Nagasaka, Y.; Nakagawa, T.; Nakajima, N.; Nitta, K.; Sakai, K.; Sakamoto, Y.; Suekane, F.; Sumiyoshi, T.; Tabata, H.; Tamura, N.; Tsuchiya, Y.

    2006-01-01

    On-site underground background measurements were performed for the planned reactor-neutrino oscillation experiment KASKA at Kashiwazaki-Kariwa nuclear power station in Niigata, Japan. A small-diameter boring hole was excavated down to 70m underground level, and a detector unit for γ-ray and cosmic-muon measurements was placed at various depths to take data. The data were analyzed to obtain abundance of natural radioactive elements in the surrounding soil and rates of cosmic muons that penetrate the overburden. The results will be reflected in the design of the KASKA experiment

  5. Theoretical considerations and preparatory experiments for poloidal field measurements in tokamaks by far-infrared polarimetry

    Energy Technology Data Exchange (ETDEWEB)

    Kunz, W; Dodel, G [Stuttgart Univ. (TH) (Germany, F.R.). Inst. fuer Plasmaforschung

    1978-12-01

    Numerical calculations give an optimum wavelength and show the precision requirements for determining poloidal field profiles in tokamaks on the basis of the Faraday effect. The required precision of the polarimetric measurements can be achieved in the far-infrared as is verified in a model experiment using a ferrite modulated HCN laser beam.

  6. Mitigation of {sup 222}Rn induced background in the XENON1T dark matter experiment

    Energy Technology Data Exchange (ETDEWEB)

    Bruenner, Stefan A.

    2017-07-05

    {sup 222}Rn is a major source of background in many rare-event experiments such as the XENON1T dark matter search. The noble gas radon is created by radioactive decay inside all detector materials and emanates into the sensitive liquid xenon target disabling any detector shielding. Subsequent beta-decays of radon progenies are the dominant source of background in the XENON1T experiment. In order to mitigate radon induced background the detector's construction materials have been selected according to dedicated {sup 222}Rn emanation measurements. In the first part of this thesis, we summarize the results of the XENON1T radon screening campaign and present the measurement of the integral radon emanation rate of the fully assembled detector. The development of a radon removal system which continuously purifies the liquid xenon target from the emanated radon is the topic of the second part of this thesis. In order to demonstrate the suitability of cryogenic distillation as a technique to separate radon from xenon, we developed an experimental setup to measure the depletion of radon in xenon boil-off gas after a single distillation step. In the last part of the thesis, we demonstrate the operation of a radon removal system for the XENON100 experiment. For this first test employing a running dark matter detector, we integrated a multiple stage, cryogenic distillation column in the XENON100 gas purification loop. From the evolution of the radon concentration in XENON100, we investigate the distillation column's radon removal capability and discuss the design and application of a radon removal system for XENON1T and the upcoming XENONnT experiment.

  7. Background studies of high energy γ rays from (n,γ) reactions in the CANDLES experiment

    Science.gov (United States)

    Nakajima, K.; Iida, T.; Akutagawa, K.; Batpurev, T.; Chan, W. M.; Dokaku, F.; Fushimi, K.; Kakubata, H.; Kanagawa, K.; Katagiri, S.; Kawasaki, K.; Khai, B. T.; Kino, H.; Kinoshita, E.; Kishimoto, T.; Hazama, R.; Hiraoka, H.; Hiyama, T.; Ishikawa, M.; Li, X.; Maeda, T.; Matsuoka, K.; Moser, M.; Nomachi, M.; Ogawa, I.; Ohata, T.; Sato, H.; Shamoto, K.; Shimada, M.; Shokati, M.; Takahashi, N.; Takemoto, Y.; Takihira, Y.; Tamagawa, Y.; Tozawa, M.; Teranishi, K.; Tetsuno, K.; Trang, V. T. T.; Tsuzuki, M.; Umehara, S.; Wang, W.; Yoshida, S.; Yotsunaga, N.

    2018-07-01

    High energy γ rays with several MeV produced by (n,γ) reactions can be a trouble for low background measurements in the underground laboratories such as double beta decay experiments. In the CANDLES project, which aimed to observe the neutrino-less double beta decay from 48Ca, γ rays caused by (n,γ) reactions were found to be the most significant background. The profile of the background was studied by measurements with a neutron source and a simulation with a validity check of neutron processes in Geant4. The observed spectrum of γ rays from (n,γ) reactions was well reproduced by the simulated spectra, which were originated from the surrounding rock and a detector tank made of stainless steel. The environmental neutron flux was derived by the observed event rate of γ rays from (n,γ) reactions using the simulation. The thermal and non-thermal neutron flux were found to be (1.3 ± 0.6) ×10-6 cm-2s-1 and (1.1 ± 0.5) ×10-5 cm-2s-1 , respectively. It is necessary to install an additional shield to reduce the background from (n,γ) reaction to the required level.

  8. Optimization of a fluorescence X-ray source and background studies for a prospective CNNS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Zoeller, Andreas; Ciemniak, Christian; Feilitzsch, Franz von; Guetlein, Achim; Haag, Nils; Hofmann, Martin; Isaila, Christian; Lanfranchi, Jean-Come; Oberauer, Lothar; Pfister, Sebastian; Potzel, Walter; Roth, Sabine; Schoenert, Stefan; Sivers, Moritz von; Strauss, Raimund [Technische Universitaet Muenchen, Physik-Department, E15 (Germany); Lachenmaier, Tobias [Eberhard Karls Universitaet, Tuebingen (Germany)

    2011-07-01

    Coherent Neutrino Nucleus Scattering (CNNS) is predicted by the Standard Model but hasn't been measured yet. A good background discrimination and shielding is essential for the achievement of a prospective experiment. We show the results of simulations for background discrimination and suppression using a myon veto system in combination with a shielding around a cryostat. With CNNS, the expected nuclear recoil energy for reactor anti-neutrinos is in the range of

  9. Late time neutrino masses, the LSND experiment, and the cosmic microwave background.

    Science.gov (United States)

    Chacko, Z; Hall, Lawrence J; Oliver, Steven J; Perelstein, Maxim

    2005-03-25

    Models with low-scale breaking of global symmetries in the neutrino sector provide an alternative to the seesaw mechanism for understanding why neutrinos are light. Such models can easily incorporate light sterile neutrinos required by the Liquid Scintillator Neutrino Detector experiment. Furthermore, the constraints on the sterile neutrino properties from nucleosynthesis and large-scale structure can be removed due to the nonconventional cosmological evolution of neutrino masses and densities. We present explicit, fully realistic supersymmetric models, and discuss the characteristic signatures predicted in the angular distributions of the cosmic microwave background.

  10. Application of point-to-point matching algorithms for background correction in on-line liquid chromatography-Fourier transform infrared spectrometry (LC-FTIR).

    Science.gov (United States)

    Kuligowski, J; Quintás, G; Garrigues, S; de la Guardia, M

    2010-03-15

    A new background correction method for the on-line coupling of gradient liquid chromatography and Fourier transform infrared spectrometry has been developed. It is based on the use of a point-to-point matching algorithm that compares the absorption spectra of the sample data set with those of a previously recorded reference data set in order to select an appropriate reference spectrum. The spectral range used for the point-to-point comparison is selected with minimal user-interaction, thus facilitating considerably the application of the whole method. The background correction method has been successfully tested on a chromatographic separation of four nitrophenols running acetonitrile (0.08%, v/v TFA):water (0.08%, v/v TFA) gradients with compositions ranging from 35 to 85% (v/v) acetonitrile, giving accurate results for both, baseline resolved and overlapped peaks. Copyright (c) 2009 Elsevier B.V. All rights reserved.

  11. Note: innovative demodulation scheme for coherent detectors in cosmic microwave background experiments.

    Science.gov (United States)

    Ishidoshiro, K; Chinone, Y; Hasegawa, M; Hazumi, M; Nagai, M; Tajima, O

    2012-05-01

    We propose an innovative demodulation scheme for coherent detectors used in cosmic microwave background polarization experiments. Removal of non-white noise, e.g., narrow-band noise, in detectors is one of the key requirements for the experiments. A combination of modulation and demodulation is used to extract polarization signals as well as to suppress such noise. Traditional demodulation, which is based on the two-point numerical differentiation, works as a first-order high pass filter for the noise. The proposed demodulation is based on the three-point numerical differentiation. It works as a second-order high pass filter. By using a real detector, we confirmed significant improvements of suppression power for the narrow-band noise. We also found improvement of the noise floor.

  12. Rate of germanium-isotope production by background processes in the SAGE experiment

    International Nuclear Information System (INIS)

    Gavrin, V.N.; Gorbachev, V.V.; Ibragimova, T.V.; Cleveland, B.T.

    2002-01-01

    Data on a direct determination of systematic uncertainties caused by the background production of germanium isotopes in the radiochemical SAGE experiment measuring the solar-neutrino flux are analyzed. The result obtained for the rate of 68 Ge production is 6.5(1±1.0) times greater than the expected one; the rate of 69 Ge production does not exceed preliminary estimates. The above result for 68 Ge corresponds to the systematic uncertainty that is caused by the interaction of cosmic-ray muons and which is equal to 5.8% (4.5 SNU) at a solar-neutrino-capture rate of 77.0 SNU. An experiment is proposed that would test the effect of cosmic-ray muon influence on the SAGE systematic uncertainty and which would be performed at the location of the underground scintillation telescope facilities of the Baksan Neutrino Observatory (Institute for Nuclear Research, Russian Academy of Sciences)

  13. The germanium isotopes production rate in background process in SAGE experiment

    International Nuclear Information System (INIS)

    Gavrin, V.N.; Gorbachev, V.V.; Ibragimova, T.V.; Cleveland, B.T.

    2002-01-01

    The analysis of the direct determination of systematics connected with the germanium isotopes generation of in background processes in radiochemical SAGE experiments on measuring solar neutrinos is described. The found 68 Ge generation rate is 6.5 (1 ± 1.0) times higher than expected; the generation rate of 69 Ge does not exceed preliminary evaluations. The result on 68 Ge corresponds to the systematic of cosmic ray muons of 5.8% (4.5 SNU) for the measured capture rate of solar neutrino of 77.0 SNU. To check the cosmic-ray muon influence of the SAGE systematic one suggests the experiment in place of underground scintillation telescope of the Baksan neutrino observatory on the Institute for Nuclear Research of the RAS [ru

  14. Background analysis for the beta-spectrum of the isotope 113Cd in the COBRA experiment

    Energy Technology Data Exchange (ETDEWEB)

    Platzek, Stephan [Technische Universitaet Dresden (Germany); Collaboration: COBRA-Collaboration

    2016-07-01

    The COBRA experiment uses Cadmium-Zinc-Telluride as detector material. This semiconductor contains several isotopes that are candidates for neutrinoless double beta-decay. Due to the natural abundance of the detector material various other isotopes are present as well. One of them is {sup 113}Cd with an abundance of about 12%. The fourfold forbidden non-unique beta-decay of {sup 113}Cd is a rare process with a half-life of about 8.10{sup 15} years. The shape of the spectrum is still topic of scientific discussions because of various forecasts given by theoretical models. The signal related to this decay is by far the most prominent in the COBRA setup causing more than 98% of the total rate. In this talk potential background components contributing to the {sup 113}Cd beta-spectrum are discussed with the aim to develop a detailed background simulation with the program VENOM (based on Geant4), that includes background sources originating from cosmic activation as well as natural radioactivity and detector specific effects.

  15. Ship Effect Neutron Measurements And Impacts On Low-Background Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Aguayo Navarrete, Estanislao [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kouzes, Richard T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Siciliano, Edward R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-10-01

    The primary particles entering the upper atmosphere as cosmic rays create showers in the atmosphere that include a broad spectrum of secondary neutrons, muons and protons. These cosmic-ray secondaries interact with materials at the surface of the Earth, yielding prompt backgrounds in radiation detection systems, as well as inducing long-lived activities through spallation events, dominated by the higher-energy neutron secondaries. For historical reasons, the multiple neutrons produced in spallation cascade events are referred to as “ship effect” neutrons. Quantifying the background from cosmic ray induced activities is important to low-background experiments, such as neutrino-less double beta decay. Since direct measurements of the effects of shielding on the cosmic-ray neutron spectrum are not available, Monte Carlo modeling is used to compute such effects. However, there are large uncertainties (orders of magnitude) in the possible cross-section libraries and the cosmic-ray neutron spectrum for the energy range needed in such calculations. The measurements reported here were initiated to validate results from Monte Carlo models through experimental measurements in order to provide some confidence in the model results. The results indicate that the models provide the correct trends of neutron production with increasing density, but there is substantial disagreement between the model and experimental results for the lower-density materials of Al, Fe and Cu.

  16. Mid infrared quantum cascade laser operating in pure amplitude modulation for background-free trace gas spectroscopy.

    Science.gov (United States)

    Bidaux, Yves; Bismuto, Alfredo; Patimisco, Pietro; Sampaolo, Angelo; Gresch, Tobias; Strubi, Gregory; Blaser, Stéphane; Tittel, Frank K; Spagnolo, Vincenzo; Muller, Antoine; Faist, Jérôme

    2016-11-14

    We present a single mode multi-section quantum cascade laser source composed of three different sections: master oscillator, gain and phase section. Non-uniform pumping of the QCL's gain reveals that the various laser sections are strongly coupled. Simulations of the electronic and optical properties of the laser (based on the density matrix and scattering matrix formalisms, respectively) were performed and a good agreement with measurements is obtained. In particular, a pure modulation of the laser output power can be achieved. This capability of the device is applied in tunable-laser spectroscopy of N2O where background-free quartz enhanced photo acoustic spectral scans with nearly perfect Voigt line shapes for the selected absorption line are obtained.

  17. The QMAP and MAT/TOCO Experiments for Measuring Anisotropy in the Cosmic Microwave Background

    Science.gov (United States)

    Miller, A.; Beach, J.; Bradley, S.; Caldwell, R.; Chapman, H.; Devlin, M. J.; Dorwart, W. B.; Herbig, T.; Jones, D.; Monnelly, G.; Netterfield, C. B.; Nolta, M.; Page, L. A.; Puchalla, J.; Robertson, T.; Torbet, E.; Tran, H. T.; Vinje, W. E.

    2002-06-01

    We describe two related experiments that measured the anisotropy in the cosmic microwave background (CMB). QMAP was a balloon-borne telescope that flew twice in 1996, collecting data on degree angular scales with an array of six high electron mobility transistor-based amplifiers (HEMTs). QMAP used an interlocking scan strategy to directly produce high signal-to-noise ratio CMB maps over a limited region of sky. The QMAP gondola was then refitted for ground-based work as the MAT/TOCO experiment. Observations were made from 5200 m on Cerro Toco in Northern Chile in 1997 and 1998 using time domain beam synthesis. MAT/TOCO measured the rise and fall of the CMB angular spectrum, thereby localizing the position of the first peak to lpeak=216+/-14. In addition to describing the instruments, we discuss the data selection methods, check for systematic errors, and compare the MAT/TOCO results to those from recent experiments. The previously reported data are updated to account for a small calibration shift and corrected to account for a small contribution from known sources of foreground emission. The resulting amplitude of the first peak for 160

  18. ForCent model development and testing using the Enriched Background Isotope Study experiment

    Energy Technology Data Exchange (ETDEWEB)

    Parton, W.J.; Hanson, P. J.; Swanston, C.; Torn, M.; Trumbore, S. E.; Riley, W.; Kelly, R.

    2010-10-01

    The ForCent forest ecosystem model was developed by making major revisions to the DayCent model including: (1) adding a humus organic pool, (2) incorporating a detailed root growth model, and (3) including plant phenological growth patterns. Observed plant production and soil respiration data from 1993 to 2000 were used to demonstrate that the ForCent model could accurately simulate ecosystem carbon dynamics for the Oak Ridge National Laboratory deciduous forest. A comparison of ForCent versus observed soil pool {sup 14}C signature ({Delta} {sup 14}C) data from the Enriched Background Isotope Study {sup 14}C experiment (1999-2006) shows that the model correctly simulates the temporal dynamics of the {sup 14}C label as it moved from the surface litter and roots into the mineral soil organic matter pools. ForCent model validation was performed by comparing the observed Enriched Background Isotope Study experimental data with simulated live and dead root biomass {Delta} {sup 14}C data, and with soil respiration {Delta} {sup 14}C (mineral soil, humus layer, leaf litter layer, and total soil respiration) data. Results show that the model correctly simulates the impact of the Enriched Background Isotope Study {sup 14}C experimental treatments on soil respiration {Delta} {sup 14}C values for the different soil organic matter pools. Model results suggest that a two-pool root growth model correctly represents root carbon dynamics and inputs to the soil. The model fitting process and sensitivity analysis exposed uncertainty in our estimates of the fraction of mineral soil in the slow and passive pools, dissolved organic carbon flux out of the litter layer into the mineral soil, and mixing of the humus layer into the mineral soil layer.

  19. Utilization of FADC for reconstruction and analysis of the background data in the Chooz neutrino experiment

    International Nuclear Information System (INIS)

    Veron, Didier

    1997-01-01

    This thesis describes a particular contribution to the Chooz experiment. The latter looks for the oscillations, over a distance of 1 km, of antineutrons emitted by two nuclear reactors. The electron-type antineutrinos are detected through their inverse beta interaction with a target's proton. The neutron is detected through its capture by a gadolinium nucleus revealed by an 8 MeV gamma emission. In the first part we describe the reconstruction of events as simulated by the GIANT software. We show that the positron's and neutron's stopping point can actually be reconstructed with an accuracy of 10 and 20 cm respectively. In the second part, we proceed to the analysis of the calibration's data as recorded with Fast Wave Form Digitizers. This confirms the reliability of the Monte-Carlo results and allows measurement of both the neutrons' capture probability and time by the target gadolinium. The last part deals with the background (reactor turned off) data analysis and the pin-pointing of its various sources. In order to reduce their contribution, we define spatial cuts. These cuts' reliability is validated by analysis of data obtained not only with a neutron source, but also with neutrons issued from cosmic rays. We end up with a background contribution of two to three events per day, about ten times less than the expected neutrino rate at full reactor power. (author)

  20. Intrinsic backgrounds from Rn and Kr in the XENON100 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Aprile, E.; Anthony, M.; Perio, P. de; Gao, F.; Goetzke, L.W.; Greene, Z.; Lin, Q.; Plante, G.; Rizzo, A.; Zhang, Y. [Columbia University, Physics Department, New York, NY (United States); Aalbers, J.; Breur, P.A.; Brown, A.; Colijn, A.P.; Decowski, M.P.; Hogenbirk, E.; Tiseni, A. [Nikhef and the University of Amsterdam, Amsterdam (Netherlands); Agostini, F. [INFN-Laboratori Nazionali del Gran Sasso, L' Aquila (Italy); Gran Sasso Science Institute, L' Aquila (Italy); University of Bologna, Department of Physics and Astrophysics, Bologna (Italy); INFN-Bologna (Italy); Alfonsi, M.; Geis, C.; Grignon, C.; Oberlack, U.; Scheibelhut, M.; Schindler, S. [Johannes Gutenberg-Universitaet Mainz, Institut fuer Physik and Exzellenzcluster PRISMA, Mainz (Germany); Amaro, F.D.; Cardoso, J.M.R.; Lopes, J.A.M.; Santos, J.M.F. dos; Silva, M. [University of Coimbra, LIBPhys, Department of Physics, Coimbra (Portugal); Arneodo, F.; Benabderrahmane, M.L.; Di Giovanni, A.; Maris, I. [New York University Abu Dhabi, Abu Dhabi (United Arab Emirates); Barrow, P.; Baudis, L.; Galloway, M.; Kazama, S.; Kessler, G.; Kish, A.; Mayani, D.; Pakarha, P.; Piastra, F.; Wulf, J. [University of Zurich, Physik-Institut, Zurich (Switzerland); Bauermeister, B.; Calven, J.; Conrad, J.; Ferella, A.D.; Moraa, K.; Pelssers, B. [Stockholm University, AlbaNova, Oskar Klein Centre, Department of Physics, Stockholm (Sweden); Berger, T.; Brown, E.; Piro, M.C. [Rensselaer Polytechnic Institute, Department of Physics, Applied Physics and Astronomy, Troy, NY (United States); Bruenner, S.; Cichon, D.; Eurin, G.; Hasterok, C.; Lindner, M.; Marrodan Undagoitia, T.; Pizzella, V.; Rauch, L.; Rupp, N.; Schreiner, J.; Simgen, H. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Bruno, G.; Rosso, A.G.; Molinario, A.; Wang, Z. [INFN-Laboratori Nazionali del Gran Sasso, L' Aquila (Italy); Gran Sasso Science Institute, L' Aquila (Italy); Budnik, R.; Itay, R.; Landsman, H.; Lellouch, D.; Levinson, L.; Manfredini, A.; Priel, N. [Weizmann Institute of Science, Department of Particle Physics and Astrophysics, Rehovot (Israel); Buetikofer, L.; Coderre, D.; Kaminsky, B.; Schumann, M.; Sivers, M. von [Universitaet Freiburg, Physikalisches Institut, Freiburg (Germany); Cervantes, M.; Lang, R.F.; Masson, D.; Reichard, S. [Purdue University, Department of Physics and Astronomy, West Lafayette, IN (United States); Cussonneau, J.P.; Diglio, S.; Masbou, J.; Micheneau, K.; Persiani, R.; Thers, D. [CNRS/IN2P3, Universite de Nantes, SUBATECH, IMT Atlantique, Nantes (France); Di Gangi, P.; Garbini, M.; Massoli, F.V.; Sartorelli, G.; Selvi, M. [University of Bologna, Department of Physics and Astrophysics, Bologna (Italy); INFN-Bologna (Italy); Fei, J.; Lombardi, F.; Ni, K.; Ye, J. [University of California, Department of Physics, San Diego, CA (United States); Fieguth, A.; Murra, M.; Vargas, M.; Weinheimer, C.; Wittweg, C. [Westfaelische Wilhelms-Universitaet Muenster, Institut fuer Kernphysik, Muenster (Germany); Fulgione, W. [INFN-Laboratori Nazionali del Gran Sasso, L' Aquila (Italy); Gran Sasso Science Institute, L' Aquila (Italy); INFN-Torino (Italy); Osservatorio Astrofisico di Torino, Torino (Italy); Lindemann, S. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Universitaet Freiburg, Physikalisches Institut, Freiburg (Germany); Messina, M. [Columbia University, Physics Department, New York, NY (United States); New York University Abu Dhabi, Abu Dhabi (United Arab Emirates); Naganoma, J.; Shagin, P. [Rice University, Department of Physics and Astronomy, Houston, TX (United States); Pienaar, J. [Purdue University, Department of Physics and Astronomy, West Lafayette, IN (United States); University of Chicago, Department of Physics, Kavli Institute of Cosmological Physics, Chicago, IL (United States); Ramirez Garcia, D. [Johannes Gutenberg-Universitaet Mainz, Institut fuer Physik and Exzellenzcluster PRISMA, Mainz (Germany); Universitaet Freiburg, Physikalisches Institut, Freiburg (Germany); Reuter, C. [University of Zurich, Physik-Institut, Zurich (Switzerland); Purdue University, Department of Physics and Astronomy, West Lafayette, IN (United States); Lavina, L.S. [Universite Paris Diderot, CNRS/IN2P3, LPNHE, Universite Pierre et Marie Curie, Paris (France); Stein, A.; Wang, H. [University of California, Physics and Astronomy Department, Los Angeles, CA (United States); Trinchero, G. [INFN-Torino (Italy); Osservatorio Astrofisico di Torino, Torino (Italy); Tunnell, C. [Nikhef and the University of Amsterdam, Amsterdam (Netherlands); University of Chicago, Department of Physics, Kavli Institute of Cosmological Physics, Chicago, IL (United States); Weber, M. [Columbia University, Physics Department, New York, NY (United States); Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Wei, Y. [University of Zurich, Physik-Institut, Zurich (Switzerland); University of California, Department of Physics, San Diego, CA (United States); Collaboration: XENON Collaboration

    2018-02-15

    In this paper, we describe the XENON100 data analyses used to assess the target-intrinsic background sources radon ({sup 222}Rn), thoron ({sup 220}Rn) and krypton ({sup 85}Kr). We detail the event selections of high-energy alpha particles and decay-specific delayed coincidences. We derive distributions of the individual radionuclides inside the detector and quantify their abundances during the main three science runs of the experiment over a period of ∝ 4 years, from January 2010 to January 2014. We compare our results to external measurements of radon emanation and krypton concentrations where we find good agreement. We report an observed reduction in concentrations of radon daughters that we attribute to the plating-out of charged ions on the negatively biased cathode. (orig.)

  1. Intrinsic backgrounds from Rn and Kr in the XENON100 experiment

    International Nuclear Information System (INIS)

    Aprile, E.; Anthony, M.; Perio, P. de; Gao, F.; Goetzke, L.W.; Greene, Z.; Lin, Q.; Plante, G.; Rizzo, A.; Zhang, Y.; Aalbers, J.; Breur, P.A.; Brown, A.; Colijn, A.P.; Decowski, M.P.; Hogenbirk, E.; Tiseni, A.; Agostini, F.; Alfonsi, M.; Geis, C.; Grignon, C.; Oberlack, U.; Scheibelhut, M.; Schindler, S.; Amaro, F.D.; Cardoso, J.M.R.; Lopes, J.A.M.; Santos, J.M.F. dos; Silva, M.; Arneodo, F.; Benabderrahmane, M.L.; Di Giovanni, A.; Maris, I.; Barrow, P.; Baudis, L.; Galloway, M.; Kazama, S.; Kessler, G.; Kish, A.; Mayani, D.; Pakarha, P.; Piastra, F.; Wulf, J.; Bauermeister, B.; Calven, J.; Conrad, J.; Ferella, A.D.; Moraa, K.; Pelssers, B.; Berger, T.; Brown, E.; Piro, M.C.; Bruenner, S.; Cichon, D.; Eurin, G.; Hasterok, C.; Lindner, M.; Marrodan Undagoitia, T.; Pizzella, V.; Rauch, L.; Rupp, N.; Schreiner, J.; Simgen, H.; Bruno, G.; Rosso, A.G.; Molinario, A.; Wang, Z.; Budnik, R.; Itay, R.; Landsman, H.; Lellouch, D.; Levinson, L.; Manfredini, A.; Priel, N.; Buetikofer, L.; Coderre, D.; Kaminsky, B.; Schumann, M.; Sivers, M. von; Cervantes, M.; Lang, R.F.; Masson, D.; Reichard, S.; Cussonneau, J.P.; Diglio, S.; Masbou, J.; Micheneau, K.; Persiani, R.; Thers, D.; Di Gangi, P.; Garbini, M.; Massoli, F.V.; Sartorelli, G.; Selvi, M.; Fei, J.; Lombardi, F.; Ni, K.; Ye, J.; Fieguth, A.; Murra, M.; Vargas, M.; Weinheimer, C.; Wittweg, C.; Fulgione, W.; Lindemann, S.; Messina, M.; Naganoma, J.; Shagin, P.; Pienaar, J.; Ramirez Garcia, D.; Reuter, C.; Lavina, L.S.; Stein, A.; Wang, H.; Trinchero, G.; Tunnell, C.; Weber, M.; Wei, Y.

    2018-01-01

    In this paper, we describe the XENON100 data analyses used to assess the target-intrinsic background sources radon ( 222 Rn), thoron ( 220 Rn) and krypton ( 85 Kr). We detail the event selections of high-energy alpha particles and decay-specific delayed coincidences. We derive distributions of the individual radionuclides inside the detector and quantify their abundances during the main three science runs of the experiment over a period of ∝ 4 years, from January 2010 to January 2014. We compare our results to external measurements of radon emanation and krypton concentrations where we find good agreement. We report an observed reduction in concentrations of radon daughters that we attribute to the plating-out of charged ions on the negatively biased cathode. (orig.)

  2. DarkSide-50, a background free experiment for dark matter searches

    International Nuclear Information System (INIS)

    Bossa, M

    2014-01-01

    The existence of dark matter is inferred from gravitational effects, but its nature remains a deep mystery. One possibility, motivated by considerations in elementary particle physics, is that dark matter consists of elementary particles, such as the hypothesized Weakly Interacting Massive Particles (WIMPs), with mass ∼ 100 GeV and cross-section ∼ 10 −47 cm 2 , that can be gravitationally trapped inside our galaxy and revealed by their scattering on nuclei. It should be possible to detect WIMPs directly, as the orbital motion of the WIMPs composing the dark matter halo pervading the galaxy should result in WIMP-nucleus collisions of sufficient energy to be observable in the laboratory. The DarkSide-50 experiment is a direct WIMP search using a Liquid Argon Time Projection Chamber (LAr-TPC) with an active mass of 50 kg with a high sensitivity and an ultra-low background detector

  3. Ultra-Sensitive Transition-Edge Sensors for the Background Limited Infrared/Sub-mm Spectrograph (BLISS)

    Science.gov (United States)

    Beyer, A. D.; Kenyon, M. E.; Echternach, P. M.; Chui, T.; Eom, B.-H.; Day, P. K.; Bock, J. J.; Holmes, W.A.; Bradford, C. M.

    2011-01-01

    We report progress in fabricating ultra-sensitive superconducting transition-edge sensors (TESs) for BLISS. BLISS is a suite of grating spectrometers covering 35-433 micron with R approx. 700 cooled to 50 mK that is proposed to fly on the Japanese space telescope SPICA. The detector arrays for BLISS are TES bolometers readout with a time domain SQUID multiplexer. The required noise equivalent power (NEP) for BLISS is NEP = 10(exp -19) W/Hz(exp 1/2) with an ultimate goal of NEP= 5 x 10(exp -20) W/Hz(exp 1/2) to achieve background limited noise performance. The required and goal response times are tau = 150 ms and tau = 50ms respectively to achieve the NEP at the required and goal optical chop frequency 1-5 Hz. We measured prototype BLISS arrays and have achieved NEP = 6 x 10(exp -18) W/Hz(exp 1/2) and tau = 1.4 ms with a Ti TES (T(sub C) = 565 mK) and NEP approx. 2.5 x 10(exp -19) W/Hz(exp 1/2) and tau approximates 4.5 ms with an Ir TES (T(sub C) = 130 mK). Dark power for these tests is estimated at 1-5 fW.

  4. Calculating exclusion limits for weakly interacting massive particle direct detection experiments without background subtraction

    International Nuclear Information System (INIS)

    Green, Anne M.

    2002-01-01

    Competitive limits on the weakly interacting massive particle (WIMP) spin-independent scattering cross section are currently being produced by 76 Ge detectors originally designed to search for neutrinoless double beta decay, such as the Heidelberg-Moscow and IGEX experiments. In the absence of background subtraction, limits on the WIMP interaction cross section are set by calculating the upper confidence limit on the theoretical event rate, given the observed event rate. The standard analysis technique involves calculating the 90% upper confidence limit on the number of events in each bin, and excluding any set of parameters (WIMP mass and cross section) which produces a theoretical event rate for any bin which exceeds the 90% upper confidence limit on the event rate for that bin. We show that, if there is more than one energy bin, this produces exclusion limits that are actually at a lower degree of confidence than 90%, and are hence erroneously tight. We formulate criteria which produce true 90% confidence exclusion limits in these circumstances, including calculating the individual bin confidence limit for which the overall probability that no bins exceed this confidence limit is 90% and calculating the 90% minimum confidence limit on the number of bins which exceed their individual bin 90% confidence limits. We then compare the limits on the WIMP cross section produced by these criteria with those found using the standard technique, using data from the Heidelberg-Moscow and IGEX experiments

  5. Background constrains of the SuperNEMO experiment for neutrinoless double beta-decay searches

    Energy Technology Data Exchange (ETDEWEB)

    Povinec, Pavel P.

    2017-02-11

    The SuperNEMO experiment is a new generation of experiments dedicated to the search for neutrinoless double beta-decay, which if observed, would confirm the existence of physics beyond the Standard Model. It is based on the tracking and calorimetry techniques, which allow the reconstruction of the final state topology, including timing and kinematics of the double beta-decay transition events, offering a powerful tool for background rejection. While the basic detection strategy of the SuperNEMO detector remains the same as of the NEMO-3 detector, a number of improvements were accomplished for each of detector main components. Upgrades of the detector technologies and development of low-level counting techniques ensure radiopurity control of construction parts of the SuperNEMO detector. A reference material made of glass pellets has been developed to assure quality management and quality control of radiopurity measurements. The first module of the SuperNEMO detector (Demonstrator) is currently under construction in the Modane underground laboratory. No background event is expected in the neutrinoless double beta-decay region in 2.5 years of its operation using 7 kg of {sup 82}Se. The half-life sensitivity of the Demonstrator is expected to be >6.5·10{sup 24} y, corresponding to an effective Majorana neutrino mass sensitivity of |0.2−0.4| eV (90% C.L.). The full SuperNEMO experiment comprising of 20 modules with 100 kg of {sup 82}Se source should reach an effective Majorana neutrino mass sensitivity of |0.04−0.1| eV, and a half-life limit 1·10{sup 26} y. - Highlights: • SuperNEMO detector for 2β0ν-decay of {sup 82}Se should reach half-life limit of 10{sup 26} y. • Radiopurity of the SuperNEMO internal detector parts was checked down to 0.1 mBq/kg. • Reference material of glass pellets was developed for underground γ-spectrometry.

  6. The electron accelerator for FELIX [Free Electron Laser for Infrared eXperiments

    International Nuclear Information System (INIS)

    Amersfoort, P.W. van; Geer, C.A.J. van der; Meer, A.F.G. van der; Bruinsma, P.J.T.; Hoekstra, R.; Kroes, F.B.; Luyckx, G.; Noomen, J.G.; Poole, M.W.; Saxon, G.

    1989-01-01

    The authors discuss the design of the electron accelerator for the Free Electron Laser for Infrared eXperiments (FELIX), which is meant to provide the Dutch science community with a rapidly tunable source of infrared radiation. The first stage of the project will (at least) cover the wavelength range between 8 and 80 μm. The accelerator consists of a triode with a grid modulated at 1 GHz, a 3.8-MeV buncher, and two travelling-wave S-band linac structures, with which 70-A, 3-ps bunches are accelerated to an energy between 15 and 4-5 MeV. The system has been designed to minimize the energy spread in the electron beam. 8 refs., 2 figs., 1 tab

  7. LHCb: Numerical Analysis of Machine Background in the LHCb Experiment for the Early and Nominal Operation of LHC

    CERN Multimedia

    Lieng, M H; Corti, G; Talanov, V

    2010-01-01

    We consider the formation of machine background induced by proton losses in the long straight section of the LHCb experiment at LHC. Both sources showering from the tertiary collimators located in the LHCb insertion region as well as local beam-gas interaction are taken into account. We present the procedure for, and results of, numerical studies of such background for various conditions. Additionally expected impact and on the experiment and signal characteristics are discussed.

  8. Concept and properties of an infrared hybrid single-beam spectrum and its application to eliminate solvent bands and other background interferences.

    Science.gov (United States)

    Chen, Yujing; Wang, Hai-Shui; Morisawa, Yusuke; Ozaki, Yukihiro

    2014-02-01

    For infrared (IR) spectral measurements, if a quality single-beam background spectrum with desired intensity could be obtained, the contributions from solvent and other background components could be completely suppressed and their bands would not appear in a final transmittance/absorbance spectrum. In order to achieve this ideal but difficult goal, the concept of hybrid single-beam spectrum is introduced in this paper. The hybrid single-beam spectrum (φ h) is defined as a mixture of two single-beam spectra (φ b1 and φ b2) of the same sample but with different pathlengths (b1 and b2), namely, φ h = αφ b1+(1-α)φ b2, where α (0 ≤ α ≤ 1) is the component factor. The properties of the hybrid spectrum have been investigated. Under conditions of b2 > b1 ≥ 0.7 b2 and A max ≤ 0.60 (Amax is the maximum absorbance of b2 sample in the spectral range of interest), all the synthesized hybrid spectra are free from significant distortion regardless of the component factor. Therefore, the hybrid single-beam spectrum with desired intensity can be easily obtained simply by choosing an appropriate component factor. The proposed methodology has been demonstrated experimentally by the complete removal of the interference from the atmospheric water vapor and solvent. © 2013 Elsevier B.V. All rights reserved.

  9. Status and Integrated Focal Plane Characterization of Simons Array - Cosmic Microwave Background Polarimetry Experiment

    Science.gov (United States)

    Roberts, Hayley; POLARBEAR

    2018-06-01

    Simons Array is a cosmic microwave background (CMB) polarization experiment located at 5,200 meter altitude site in the Atacama desert in Chile. The science goals of the Simons Array are to characterize the CMB B-mode signal from gravitational lensing, and search for B-mode polarization generated from inflationary gravitational waves.In 2012, POLARBEAR-1 (PB-1) began observations and the POLARBEAR team has published the first measurements of non-zero polarization B-mode polarization angular power spectrum where gravitational lensing of CMB is the dominant signal.POLARBEAR-2A (PB-2A), the first of three receivers of Simons Array, will have 7,588 polarization sensitive Transition Edge Sensor (TES) bolometers with frequencies 90 GHz and 150 GHz. This represents a factor of 6 increase in detector count compared to PB-1. Once Simons Array is fully deployed, the focal plane array will consist 22,764 TES bolometers across 90 GHz, 150 GHz, 220 GHz, and 270 GHz with a projected instantaneous sensitivity of 2.5 µK√s. Here we present the status of PB-2A and characterization of the integrated focal plane to be deployed summer of 2018.

  10. Bayesian Noise Estimation for Non-ideal Cosmic Microwave Background Experiments

    Science.gov (United States)

    Wehus, I. K.; Næss, S. K.; Eriksen, H. K.

    2012-03-01

    We describe a Bayesian framework for estimating the time-domain noise covariance of cosmic microwave background (CMB) observations, typically parameterized in terms of a 1/f frequency profile. This framework is based on the Gibbs sampling algorithm, which allows for exact marginalization over nuisance parameters through conditional probability distributions. In this paper, we implement support for gaps in the data streams and marginalization over fixed time-domain templates, and also outline how to marginalize over confusion from CMB fluctuations, which may be important for high signal-to-noise experiments. As a by-product of the method, we obtain proper constrained realizations, which themselves can be useful for map making. To validate the algorithm, we demonstrate that the reconstructed noise parameters and corresponding uncertainties are unbiased using simulated data. The CPU time required to process a single data stream of 100,000 samples with 1000 samples removed by gaps is 3 s if only the maximum posterior parameters are required, and 21 s if one also wants to obtain the corresponding uncertainties by Gibbs sampling.

  11. BAYESIAN NOISE ESTIMATION FOR NON-IDEAL COSMIC MICROWAVE BACKGROUND EXPERIMENTS

    International Nuclear Information System (INIS)

    Wehus, I. K.; Næss, S. K.; Eriksen, H. K.

    2012-01-01

    We describe a Bayesian framework for estimating the time-domain noise covariance of cosmic microwave background (CMB) observations, typically parameterized in terms of a 1/f frequency profile. This framework is based on the Gibbs sampling algorithm, which allows for exact marginalization over nuisance parameters through conditional probability distributions. In this paper, we implement support for gaps in the data streams and marginalization over fixed time-domain templates, and also outline how to marginalize over confusion from CMB fluctuations, which may be important for high signal-to-noise experiments. As a by-product of the method, we obtain proper constrained realizations, which themselves can be useful for map making. To validate the algorithm, we demonstrate that the reconstructed noise parameters and corresponding uncertainties are unbiased using simulated data. The CPU time required to process a single data stream of 100,000 samples with 1000 samples removed by gaps is 3 s if only the maximum posterior parameters are required, and 21 s if one also wants to obtain the corresponding uncertainties by Gibbs sampling.

  12. Target Group Segmentation in the Horse Buyers' Market against the Background of Equestrian Experience.

    Science.gov (United States)

    Gille, Claudia; Kayser, Maike; Spiller, Achim

    2010-01-01

    Whereas in former times horses were reserved primarily for people involved in agriculture, elite equestrians or the military, nowadays equestrian sport has become an activity for people with a wide variety of backgrounds. However, as more and more people become involved with equestrian sport today, the knowledge concerning animal husbandry in general is diminishing due to an alienation from agricultural themes in modern societies. As a consequence, this development affects both riding ability and the appraisal of horses, especially with respect to the purchase of horses. In order to analyse which factors influence purchase decisions in the horse market in conjunction with equestrian experience, 739 horse riders were surveyed on their purchase behaviour in this study. Using cluster analysis, a typology was generated that provides a differentiated picture of the preferences of the various rider groups. Three clusters were distinguished: the "amateurs", the "experienced" and the "experts". Taking personal horse riding proficiency into account, it could be concluded that especially the "amateur" group required objective criteria for the evaluation of a horse they are considering purchasing. Alongside "measureable" qualities, such as previous showing success or the level of training of the horse, also other attributes such as the simple handling of the horse should be taken into consideration. As particularly the "amateur" group in equestrian sport is increasing in numbers, it is therefore advisable when preparing a horse for sale to align oneself to the needs of this customer segment in order to ensure an effective and targeted marketing of horses.

  13. BAYESIAN NOISE ESTIMATION FOR NON-IDEAL COSMIC MICROWAVE BACKGROUND EXPERIMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Wehus, I. K. [Theoretical Physics, Imperial College London, London SW7 2AZ (United Kingdom); Naess, S. K.; Eriksen, H. K., E-mail: i.k.wehus@fys.uio.no, E-mail: sigurdkn@astro.uio.no, E-mail: h.k.k.eriksen@astro.uio.no [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029, Blindern, N-0315 Oslo (Norway)

    2012-03-01

    We describe a Bayesian framework for estimating the time-domain noise covariance of cosmic microwave background (CMB) observations, typically parameterized in terms of a 1/f frequency profile. This framework is based on the Gibbs sampling algorithm, which allows for exact marginalization over nuisance parameters through conditional probability distributions. In this paper, we implement support for gaps in the data streams and marginalization over fixed time-domain templates, and also outline how to marginalize over confusion from CMB fluctuations, which may be important for high signal-to-noise experiments. As a by-product of the method, we obtain proper constrained realizations, which themselves can be useful for map making. To validate the algorithm, we demonstrate that the reconstructed noise parameters and corresponding uncertainties are unbiased using simulated data. The CPU time required to process a single data stream of 100,000 samples with 1000 samples removed by gaps is 3 s if only the maximum posterior parameters are required, and 21 s if one also wants to obtain the corresponding uncertainties by Gibbs sampling.

  14. Measurement of the cosmic microwave background polarization lensing power spectrum with the POLARBEAR experiment.

    Science.gov (United States)

    Ade, P A R; Akiba, Y; Anthony, A E; Arnold, K; Atlas, M; Barron, D; Boettger, D; Borrill, J; Chapman, S; Chinone, Y; Dobbs, M; Elleflot, T; Errard, J; Fabbian, G; Feng, C; Flanigan, D; Gilbert, A; Grainger, W; Halverson, N W; Hasegawa, M; Hattori, K; Hazumi, M; Holzapfel, W L; Hori, Y; Howard, J; Hyland, P; Inoue, Y; Jaehnig, G C; Jaffe, A; Keating, B; Kermish, Z; Keskitalo, R; Kisner, T; Le Jeune, M; Lee, A T; Linder, E; Leitch, E M; Lungu, M; Matsuda, F; Matsumura, T; Meng, X; Miller, N J; Morii, H; Moyerman, S; Myers, M J; Navaroli, M; Nishino, H; Paar, H; Peloton, J; Quealy, E; Rebeiz, G; Reichardt, C L; Richards, P L; Ross, C; Schanning, I; Schenck, D E; Sherwin, B; Shimizu, A; Shimmin, C; Shimon, M; Siritanasak, P; Smecher, G; Spieler, H; Stebor, N; Steinbach, B; Stompor, R; Suzuki, A; Takakura, S; Tomaru, T; Wilson, B; Yadav, A; Zahn, O

    2014-07-11

    Gravitational lensing due to the large-scale distribution of matter in the cosmos distorts the primordial cosmic microwave background (CMB) and thereby induces new, small-scale B-mode polarization. This signal carries detailed information about the distribution of all the gravitating matter between the observer and CMB last scattering surface. We report the first direct evidence for polarization lensing based on purely CMB information, from using the four-point correlations of even- and odd-parity E- and B-mode polarization mapped over ∼30 square degrees of the sky measured by the POLARBEAR experiment. These data were analyzed using a blind analysis framework and checked for spurious systematic contamination using null tests and simulations. Evidence for the signal of polarization lensing and lensing B modes is found at 4.2σ (stat+sys) significance. The amplitude of matter fluctuations is measured with a precision of 27%, and is found to be consistent with the Lambda cold dark matter cosmological model. This measurement demonstrates a new technique, capable of mapping all gravitating matter in the Universe, sensitive to the sum of neutrino masses, and essential for cleaning the lensing B-mode signal in searches for primordial gravitational waves.

  15. Identification of backgrounds in the EDELWEISS-I dark matter search experiment

    Energy Technology Data Exchange (ETDEWEB)

    Fiorucci, S. [CEA, Centre d' Etudes Nucleaires de Saclay, DSM/DAPNIA, 91191 Gif-sur-Yvette Cedex (France); Benoit, A. [Centre de Recherche sur les Tres Basses Temperatures, SPM-CNRS, BP 166, 38042 Grenoble (France); Berge, L. [Centre de Spectroscopie Nucleaire et de Spectroscopie de Masse, UMR8609 IN2P3-CNRS, Univ. Paris Sud, bat 108, 91405 Orsay Campus (France)] (and others)

    2007-05-15

    This paper presents our interpretation and understanding of the different backgrounds in the EDELWEISS-I data sets. We analyze in detail the several populations observed, which include gammas, alphas, neutrons, thermal sensor events and surface events, and try to combine all data sets to provide a coherent picture of the nature and localization of the background sources. In light of this interpretation, we draw conclusions regarding the background suppression scheme for the EDELWEISS-II phase. (authors)

  16. Identification of backgrounds in the EDELWEISS-I dark matter search experiment

    Energy Technology Data Exchange (ETDEWEB)

    Fiorucci, S. [CEA, Centre d' Etudes Nucleaires de Saclay, DSM/DAPNIA, 91191 Gif-sur-Yvette Cedex (France); Benoit, A. [Centre de Recherche sur les Tres Basses Temperatures, SPM-CNRS, BP 166, 38042 Grenoble (France); Berge, L. [Centre de Spectroscopie Nucleaire et de Spectroscopie de Masse, UMR 8609 IN2P3-CNRS, Univ. Paris Sud, bat 108, 91405 Orsay Campus (France)] (and others)

    2006-10-15

    This paper presents our interpretation and understanding of the different backgrounds in the EDELWEISS-I data sets. We analyze in detail the several populations observed, which include gammas, alphas, neutrons, thermal sensor events and surface events, and try to combine all data sets to provide a coherent picture of the nature and localisation of the background sources. In light of this interpretation, we draw conclusions regarding the background suppression scheme for the EDELWEISS-II phase. (authors)

  17. Inverse Compton X-Ray Halos Around High-z Radio Galaxies: A Feedback Mechanism Powered by Far-Infrared Starbursts or the Cosmic Microwave Background?

    Science.gov (United States)

    Small, Ian; Blundell, Katherine M.; Lehmer, B. D.; Alexander, D. M.

    2012-01-01

    We report the detection of extended X-ray emission around two powerful radio galaxies at z approx. 3.6 (4C 03.24 and 4C 19.71) and use these to investigate the origin of extended, inverse Compton (IC) powered X-ray halos at high redshifts. The halos have X-ray luminosities of L(sub X) approx. 3 x 10(exp 44) erg/s and sizes of approx.60 kpc. Their morphologies are broadly similar to the approx.60 kpc long radio lobes around these galaxies suggesting they are formed from IC scattering by relativistic electrons in the radio lobes, of either cosmic microwave background (CMB) photons or far-infrared photons from the dust-obscured starbursts in these galaxies. These observations double the number of z > 3 radio galaxies with X-ray-detected IC halos. We compare the IC X-ray-to-radio luminosity ratios for the two new detections to the two previously detected z approx. 3.8 radio galaxies. Given the similar redshifts, we would expect comparable X-ray IC luminosities if millimeter photons from the CMB are the dominant seed field for the IC emission (assuming all four galaxies have similar ages and jet powers). Instead we see that the two z approx. 3.6 radio galaxies, which are 4 fainter in the far-infrared than those at z 3.8, also have approx.4x fainter X-ray IC emission. Including data for a further six z > or approx. 2 radio sources with detected IC X-ray halos from the literature, we suggest that in the more compact, majority of radio sources, those with lobe sizes < or approx.100-200 kpc, the bulk of the IC emission may be driven by scattering of locally produced far-infrared photons from luminous, dust-obscured starbursts within these galaxies, rather than millimeter photons from the CMB. The resulting X-ray emission appears sufficient to ionize the gas on approx.100-200 kpc scales around these systems and thus helps form the extended, kinematically quiescent Ly(alpha) emission line halos found around some of these systems. The starburst and active galactic nucleus

  18. Target Group Segmentation in the Horse Buyers’ Market against the Background of Equestrian Experience

    Science.gov (United States)

    GILLE, Claudia; KAYSER, Maike; SPILLER, Achim

    2011-01-01

    Whereas in former times horses were reserved primarily for people involved in agriculture, elite equestrians or the military, nowadays equestrian sport has become an activity for people with a wide variety of backgrounds. However, as more and more people become involved with equestrian sport today, the knowledge concerning animal husbandry in general is diminishing due to an alienation from agricultural themes in modern societies. As a consequence, this development affects both riding ability and the appraisal of horses, especially with respect to the purchase of horses. In order to analyse which factors influence purchase decisions in the horse market in conjunction with equestrian experience, 739 horse riders were surveyed on their purchase behaviour in this study. Using cluster analysis, a typology was generated that provides a differentiated picture of the preferences of the various rider groups. Three clusters were distinguished: the “amateurs”, the “experienced” and the “experts”. Taking personal horse riding proficiency into account, it could be concluded that especially the “amateur” group required objective criteria for the evaluation of a horse they are considering purchasing. Alongside “measureable” qualities, such as previous showing success or the level of training of the horse, also other attributes such as the simple handling of the horse should be taken into consideration. As particularly the “amateur” group in equestrian sport is increasing in numbers, it is therefore advisable when preparing a horse for sale to align oneself to the needs of this customer segment in order to ensure an effective and targeted marketing of horses. PMID:24833979

  19. Muonic background in the GERDA 0νββ experiment

    Energy Technology Data Exchange (ETDEWEB)

    Freund, Kai Lorenz

    2014-07-18

    Muons can cause a non-negligible background in rare-event experiments like GERDA which searches for the neutrinoless double-beta decay (0νββ) in the isotope {sup 76}Ge. The kinetic energy of cosmogenic muons depends on the progenitor particle, hence they can have an energy which is high enough to penetrate even the deepest underground laboratory. For this reason GERDA is equipped with a powerful muon veto system which in most parts was developed in Tuebingen. In this work, a plastic scintillator veto was added to the existing water Cherenkov veto in order to protect a weak spot. Existing hardware was maintained, frequently calibrated and faulty modules exchanged when possible. The DAQ and analysis was upgraded in order to run both veto systems simultaneously. The system was simulated with a GEANT4-based Monte-Carlo simulation. Multiplicity and photon spectra of the simulations were found to be in good agreement with the experimental data and give an efficiency for the detection of energy-depositing muons of ε{sup sim}{sub μd}=(99.935±0.015)%. Two external effects were clearly identified in the muon veto data: additional muons originating from the CNGS-beam at CERN and an annual flux modulation due to seasonal atmospheric temperature changes. Both effects were measured with high precision and agree well with other experiments. Coincidences with the germanium detectors were studied and muon-germanium coincidences were clearly identified. By defining a muon cut, a muon rejection efficiency of the germanium detectors of ε{sup Ge}{sub μr}=(99.2{sup +0.3}{sub -0.4})% was found. Two methods were pursued to find radioactive isotopes produced by muons through spallation or neutron activation. The result of both methods is compatible with zero, i.e. no events could be clearly identified. The overall functionality of the muon veto for Phase I of GERDA was successfully maintained and verified.

  20. Scientific results from the cosmic background explorer (COBE)

    International Nuclear Information System (INIS)

    Bennett, C.L.; Boggess, N.W.; Cheng, E.S.; Hauser, M.G.; Kelsall, T.; Mather, J.C.; Moseley, S.H. Jr.; Shafer, R.A.; Silverberg, R.F.; Murdock, T.L.; Smoot, G.F.; Weiss, R.; Wright, E.L.

    1993-01-01

    The National Aeronautics and Space Administration (NASA) has flown the COBE satellite to observe the Big Bang and the subsequent formation of galaxies and large-scale structure. Data from the Far-Infrared Absolute Spectrophotometer (FIRAS) show that the spectrum of the cosmic microwave background is that of a black body of temperature T = 2.73 ± 0.06 K, with no deviation from a black-body spectrum greater than 0.25% of the peak brightness. The data from the Differential Microwave Radiometers (DMR) show statistically significant cosmic microwave background anisotropy, consistent with a scale-invariant primordial density fluctuation spectrum. Measurements from the Diffuse Infrared Background Experiment (DIRBE) provide new conservation upper limits to the cosmic infrared background. Extensive modeling of solar system and galactic infrared foregrounds is required for further improvement in the cosmic infrared background limits. 104 refs., 1 tab

  1. Infrared Emission Spectrum of the Hydroxyl Radical: A Novel Experiment in Molecular Spectroscopy.

    Science.gov (United States)

    Henderson, Giles; And Others

    1982-01-01

    Describes an experiment in which parameters from an "ab-initio" potential are used to calculate vibrational-rotational energy levels and construct a "stick spectrum" for the overtone emission of the hydroxyl radical. Provides background information on ab-initio spectrum, experimental procedures, and analysis of data. (Author/JN)

  2. LArGe: active background suppression using argon scintillation for the GERDA 0νββ-experiment

    International Nuclear Information System (INIS)

    Agostini, M.; Budjas, D.; Schoenert, S.; Barnabe-Heider, M.; Cattadori, C.; Gangapshev, A.; Gusev, K.; Heisel, M.; Smolnikov, A.; Junker, M.; Klimenko, A.; Lubashevskiy, A.; Pelczar, K.; Zuzel, G.

    2015-01-01

    LArGe is a GERDA low-background test facility to study novel background suppression methods in a low-background environment, for future application in the GERDA experiment. Similar to GERDA, LArGe operates bare germanium detectors submersed into liquid argon (1 m 3 , 1.4tons), which in addition is instrumented with photomultipliers to detect argon scintillation light. The scintillation signals are used in anti-coincidence with the germanium detectors to effectively suppress background events that deposit energy in the liquid argon. The background suppression efficiency was studied in combination with a pulse shape discrimination (PSD) technique using a BEGe detector for various sources, which represent characteristic backgrounds to GERDA. Suppression factors of a few times 10 3 have been achieved. First background data of LArGe with a coaxial HPGe detector (without PSD) yield a background index of (0.12 - 4.6) x 10 -2 cts/(keV kg year) (90 % C.L.), which is at the level of GERDA Phase I. Furthermore, for the first time we monitor the natural 42 Ar abundance (parallel to GERDA), and have indication for the 2νββ-decay in natural germanium. These results show the effectivity of an active liquid argon veto in an ultra-low background environment. As a consequence, the implementation of a liquid argon veto in GERDA Phase II is pursued. (orig.)

  3. LArGe: active background suppression using argon scintillation for the Gerda 0ν β β -experiment

    Science.gov (United States)

    Agostini, M.; Barnabé-Heider, M.; Budjáš, D.; Cattadori, C.; Gangapshev, A.; Gusev, K.; Heisel, M.; Junker, M.; Klimenko, A.; Lubashevskiy, A.; Pelczar, K.; Schönert, S.; Smolnikov, A.; Zuzel, G.

    2015-10-01

    LArGe is a Gerda low-background test facility to study novel background suppression methods in a low-background environment, for future application in the Gerda experiment. Similar to Gerda, LArGe operates bare germanium detectors submersed into liquid argon (1 m^3, 1.4 tons), which in addition is instrumented with photomultipliers to detect argon scintillation light. The scintillation signals are used in anti-coincidence with the germanium detectors to effectively suppress background events that deposit energy in the liquid argon. The background suppression efficiency was studied in combination with a pulse shape discrimination (PSD) technique using a BEGe detector for various sources, which represent characteristic backgrounds to Gerda. Suppression factors of a few times 10^3 have been achieved. First background data of LArGe with a coaxial HPGe detector (without PSD) yield a background index of (0.12-4.6)× 10^{-2} cts/(keV kg year) (90 % C.L.), which is at the level of Gerda Phase I. Furthermore, for the first time we monitor the natural ^{42}Ar abundance (parallel to Gerda), and have indication for the 2ν β β -decay in natural germanium. These results show the effectivity of an active liquid argon veto in an ultra-low background environment. As a consequence, the implementation of a liquid argon veto in Gerda Phase II is pursued.

  4. LArGe: active background suppression using argon scintillation for the GERDA 0νββ-experiment

    Energy Technology Data Exchange (ETDEWEB)

    Agostini, M.; Budjas, D.; Schoenert, S. [Technische Universitaet Muenchen, Munich (Germany); Barnabe-Heider, M. [Technische Universitaet Muenchen, Munich (Germany); Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Cattadori, C. [Universita degli Studi di Milano, Milan (Italy); INFN, Milan (Italy); Gangapshev, A. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Institut for Nuclear Research, Moscow (Russian Federation); Gusev, K. [Technische Universitaet Muenchen, Munich (Germany); Joint Institut for Nuclear Research, Dubna (Russian Federation); National Research Center Kurchatov Institut, Moscow (Russian Federation); Heisel, M.; Smolnikov, A. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Junker, M. [Laboratori Nazionali del Gran Sasso, Assergi (Italy); Klimenko, A.; Lubashevskiy, A. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Joint Institut for Nuclear Research, Dubna (Russian Federation); Pelczar, K. [Jagellonian University, Cracow (Poland); Zuzel, G. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Jagellonian University, Cracow (Poland)

    2015-10-15

    LArGe is a GERDA low-background test facility to study novel background suppression methods in a low-background environment, for future application in the GERDA experiment. Similar to GERDA, LArGe operates bare germanium detectors submersed into liquid argon (1 m{sup 3}, 1.4tons), which in addition is instrumented with photomultipliers to detect argon scintillation light. The scintillation signals are used in anti-coincidence with the germanium detectors to effectively suppress background events that deposit energy in the liquid argon. The background suppression efficiency was studied in combination with a pulse shape discrimination (PSD) technique using a BEGe detector for various sources, which represent characteristic backgrounds to GERDA. Suppression factors of a few times 10{sup 3} have been achieved. First background data of LArGe with a coaxial HPGe detector (without PSD) yield a background index of (0.12 - 4.6) x 10{sup -2} cts/(keV kg year) (90 % C.L.), which is at the level of GERDA Phase I. Furthermore, for the first time we monitor the natural {sup 42}Ar abundance (parallel to GERDA), and have indication for the 2νββ-decay in natural germanium. These results show the effectivity of an active liquid argon veto in an ultra-low background environment. As a consequence, the implementation of a liquid argon veto in GERDA Phase II is pursued. (orig.)

  5. Pre operational background radiation monitoring around Kudankulam Nuclear Power Project site - a decade long experience

    International Nuclear Information System (INIS)

    Vijayakumar, B.; George, Thomas; Sundara Rajan, P.; Selvi, B.S.; Balamurugan, M.; Pandit, G.G.; Ravi, P.M.; Tripathi, R.M.

    2014-01-01

    Pre-operational environmental background radiation monitoring around nuclear power plants is very important to understand baseline values existing in the site and also to identify any hot spots of naturally occurring high background radiation areas and their sources. These baseline measurements will act as a benchmark for future comparison after the reactors go into operation. The radiation measurements are continued during the operational phase of the plant and the results are compared to see whether there is any impact of the operation of the plant on the environment. A comprehensive background radiation monitoring plan has been in vogue at site from 2004 to meet this objective. This paper describes the different monitoring strategies adopted around Kudankulam Nuclear Power Project site and throws light on the pre operational background radiation levels in the environment

  6. Infrared variation reduction by simultaneous background suppression and target contrast enhancement for deep convolutional neural network-based automatic target recognition

    Science.gov (United States)

    Kim, Sungho

    2017-06-01

    Automatic target recognition (ATR) is a traditionally challenging problem in military applications because of the wide range of infrared (IR) image variations and the limited number of training images. IR variations are caused by various three-dimensional target poses, noncooperative weather conditions (fog and rain), and difficult target acquisition environments. Recently, deep convolutional neural network-based approaches for RGB images (RGB-CNN) showed breakthrough performance in computer vision problems, such as object detection and classification. The direct use of RGB-CNN to the IR ATR problem fails to work because of the IR database problems (limited database size and IR image variations). An IR variation-reduced deep CNN (IVR-CNN) to cope with the problems is presented. The problem of limited IR database size is solved by a commercial thermal simulator (OKTAL-SE). The second problem of IR variations is mitigated by the proposed shifted ramp function-based intensity transformation. This can suppress the background and enhance the target contrast simultaneously. The experimental results on the synthesized IR images generated by the thermal simulator (OKTAL-SE) validated the feasibility of IVR-CNN for military ATR applications.

  7. Construction, Deployment and Data Analysis of the E and B EXperiment: A Cosmic Microwave Background Polarimeter

    Science.gov (United States)

    Didier, Joy

    The E and B EXperiment (EBEX) is a pointed balloon-borne telescope designed to measure the polarization of the cosmic microwave background (CMB) as well as that from Galactic dust. The instrument is equipped with a 1.5 meter aperture Gregorian-Dragone telescope, providing an 8' beam at three frequency bands centered on 150, 250 and 410 GHz. The telescope is designed to measure or place an upper limit on inflationary B-mode signals and to probe B-modes originating from gravitationnal lensing of the CMB. The higher EBEX frequencies are designed to enable the measurement and removal of polarized Galactic dust foregrounds which currently limit the measurement of inflationary B-modes. Polarimetry is achieved by rotating an achromatic half-wave plate (HWP) on a superconducting magnetic bearing. In January 2013, EBEX completed 11 days of observations in a flight over Antarctica covering 6,000 square degrees of the southern sky. This marks the first time that kilo-pixel TES bolometer arrays have made science observations on a balloon-borne platform. In this thesis we report on the construction, deployment and data analysis of EBEX. We review the development of the pointing sensors and software used for real-time attitude determination and control, including pre-flight testing and calibration. We then report on the 2013 long duration flight (LD2013) and review all the major stages of the analysis pipeline used to transform the ˜1 TB of raw data into polarized sky maps. We review "LEAP", the software framework developed to support the analysis pipeline. We discuss in detail the novel program developed to reconstruct the attitude post-flight and estimate the effect of attitude errors on measured B-mode signals. We describe the bolometer time-stream cleaning procedure including removing the HWP-synchronous signal, and we detail the map making procedure. Finally we present a novel method to measure and subtract instrumental polarization, after which we show Galaxy and CMB maps.

  8. Diabetes nurse educators' experiences of providing care for women, with gestational diabetes mellitus, from disadvantaged backgrounds.

    Science.gov (United States)

    Carolan, Mary

    2014-05-01

    To explore diabetes nurse educators' experiences of providing care for women, with gestational diabetes mellitus, from disadvantaged backgrounds and to gather information which would assist with the development of an educational programme that would support both women and diabetes educators. Rates of gestational diabetes mellitus have increased dramatically in recent years. This is concerning as gestational diabetes mellitus is linked to poorer pregnancy outcomes including hypertension, stillbirth, and nursery admission. Poorest outcomes occur among disadvantaged women. gestational diabetes mellitus is also associated with maternal type 2 diabetes and with child obesity and type 2 diabetes among offspring. Effective self-management of gestational diabetes mellitus reduces these risks. Diabetes nurse educators provide most education and support for gestational diabetes mellitus self-management. An interpretative phenomenological analysis approach, as espoused by Smith and Osborn (Qualitative Psychology: A Practical Guide to Research Methods, 2008, Sage, London, 51), provided the framework for this study. The views of six diabetes educators were explored through in-depth interviewing. Interviews were transcribed verbatim and analysed according to steps outlined by Smith and Osborn (Qualitative Psychology: A Practical Guide to Research Methods, 2008, Sage, London, 51). Three themes emerged from the data: (1) working in a suboptimal environment, (2) working to address the difficulties and (3) looking to the future. Throughout, the diabetes nurse educators sought opportunities to connect with women in their care and to make the educational content understandable and meaningful. Low literacy among disadvantaged women has a significant impact on their understanding of gestational diabetes mellitus information. In turn, catering for women with low literacy contributes to increased workloads for diabetes nurse educators, making them vulnerable to burnout. There is a need

  9. Capturing the guest experience in hotels phase one : theoretical background and development of the guest experience scan

    NARCIS (Netherlands)

    Marle, van R.S.F. (Rienk); Pijls, R. (Ruth); Schreiber, G.H. (Gerrit)

    2011-01-01

    The goal for the coming years is to get insight in the guest experience in hotels. What is guest experience? How to measure guest experience? What is the relation between guest experience and guest loyalty? And finally, what tangible elements in the physical environment of hotels and the contact

  10. The Influence of Social and Family Backgrounds on College Transition Experiences of Foster Youth

    Science.gov (United States)

    Franco, Joaquin; Durdella, Nathan

    2018-01-01

    Familial and social experiences shape college transitions of first-year, first-generation college students who are foster youth. This chapter describes these experiences and offers recommendations to enhance support for foster youth in college.

  11. Exposure to space radiation of high-performance infrared multilayer filters and materials technology experiments (A0056)

    Science.gov (United States)

    Seeley, J. S.; Hunneman, R.; Whatley, A.; Lipscombe, D. R.

    1984-01-01

    Infrared multilayer interface filter which were used in satellite radiometers were examined. The ability of the filters to withstand the space environment in these applications is critical. An experiment on the LDEF subjects the filters to authoritative spectral measurements following space exposure to ascertain their suitability for spacecraft use and to permit an understanding of degradation mechanisms. The understanding of the effects of prolonged space exposure on spacecraft materials, surface finishes, and adhesive systems is important to the spacecraft designer. Materials technology experiments and experiment on infrared multilayer filters are discussed.

  12. Laboratory Experiments on Propagating Plasma Bubbles into Vacuum, Vacuum Magnetic Field, and Background Plasmas

    Science.gov (United States)

    Lynn, Alan G.; Zhang, Yue; Gilmore, Mark; Hsu, Scott

    2014-10-01

    We discuss the dynamics of plasma ``bubbles'' as they propagate through a variety of background media. These bubbles are formed by a pulsed coaxial gun with an externally applied magnetic field. Bubble parameters are typically ne ~1020 m-3, Te ~ 5 - 10 eV, and Ti ~ 10 - 15 eV. The structure of the bubbles can range from unmagnetized jet-like structures to spheromak-like structures with complex magnetic flux surfaces. Some of the background media the bubbles interact with are vacuum, vacuum with magnetic field, and other magnetized plasmas. These bubbles exhibit different qualitative behavior depending on coaxial gun parameters such as gas species, gun current, and gun bias magnetic field. Their behavior also depends on the parameters of the background they propagate through. Multi-frame fast camera imaging and magnetic probe data are used to characterize the bubble evolution under various conditions.

  13. INVERSE COMPTON X-RAY HALOS AROUND HIGH-z RADIO GALAXIES: A FEEDBACK MECHANISM POWERED BY FAR-INFRARED STARBURSTS OR THE COSMIC MICROWAVE BACKGROUND?

    Energy Technology Data Exchange (ETDEWEB)

    Smail, Ian [Institute for Computational Cosmology, Durham University, South Road, Durham DH1 3LE (United Kingdom); Blundell, Katherine M. [Department of Astrophysics, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom); Lehmer, B. D. [Department of Physics and Astronomy, The Johns Hopkins University, Homewood Campus, Baltimore, MD 21218 (United States); Alexander, D. M. [Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom)

    2012-12-01

    We report the detection of extended X-ray emission around two powerful radio galaxies at z {approx} 3.6 (4C 03.24 and 4C 19.71) and use these to investigate the origin of extended, inverse Compton (IC) powered X-ray halos at high redshifts. The halos have X-ray luminosities of L {sub X} {approx} 3 Multiplication-Sign 10{sup 44} erg s{sup -1} and sizes of {approx}60 kpc. Their morphologies are broadly similar to the {approx}60 kpc long radio lobes around these galaxies suggesting they are formed from IC scattering by relativistic electrons in the radio lobes, of either cosmic microwave background (CMB) photons or far-infrared photons from the dust-obscured starbursts in these galaxies. These observations double the number of z > 3 radio galaxies with X-ray-detected IC halos. We compare the IC X-ray-to-radio luminosity ratios for the two new detections to the two previously detected z {approx} 3.8 radio galaxies. Given the similar redshifts, we would expect comparable X-ray IC luminosities if millimeter photons from the CMB are the dominant seed field for the IC emission (assuming all four galaxies have similar ages and jet powers). Instead we see that the two z {approx} 3.6 radio galaxies, which are {approx}4 Multiplication-Sign fainter in the far-infrared than those at z {approx} 3.8, also have {approx}4 Multiplication-Sign fainter X-ray IC emission. Including data for a further six z {approx}> 2 radio sources with detected IC X-ray halos from the literature, we suggest that in the more compact, majority of radio sources, those with lobe sizes {approx}<100-200 kpc, the bulk of the IC emission may be driven by scattering of locally produced far-infrared photons from luminous, dust-obscured starbursts within these galaxies, rather than millimeter photons from the CMB. The resulting X-ray emission appears sufficient to ionize the gas on {approx}100-200 kpc scales around these systems and thus helps form the extended, kinematically quiescent Ly{alpha} emission line

  14. Measuring Attitude towards RE: Factoring Pupil Experience and Home Faith Background into Assessment

    Science.gov (United States)

    Thanissaro, Phra Nicholas

    2012-01-01

    Recent studies have increasingly favoured contextualisation of religious education (RE) to pupils' home faith background in spite of current assessment methods that might hinder this. For a multi-religious, multi-ethnic sample of 369 London school pupils aged from 13 to 15 years, this study found that the participatory, transformative and…

  15. Confidence intervals for experiments with background and small numbers of events

    International Nuclear Information System (INIS)

    Bruechle, W.

    2003-01-01

    Methods to find a confidence interval for Poisson distributed variables are illuminated, especially for the case of poor statistics. The application of 'central' and 'highest probability density' confidence intervals is compared for the case of low count-rates. A method to determine realistic estimates of the confidence intervals for Poisson distributed variables affected with background, and their ratios, is given. (orig.)

  16. Confidence intervals for experiments with background and small numbers of events

    International Nuclear Information System (INIS)

    Bruechle, W.

    2002-07-01

    Methods to find a confidence interval for Poisson distributed variables are illuminated, especially for the case of poor statistics. The application of 'central' and 'highest probability density' confidence intervals is compared for the case of low count-rates. A method to determine realistic estimates of the confidence intervals for Poisson distributed variables affected with background, and their ratios, is given. (orig.)

  17. Background Music in the Dissection Laboratory: Impact on Stress Associated with the Dissection Experience

    Science.gov (United States)

    Anyanwu, Emeka G.

    2015-01-01

    Notable challenges, such as mental distress, boredom, negative moods, and attitudes, have been associated with learning in the cadaver dissection laboratory (CDL). The ability of background music (BM) to enhance the cognitive abilities of students is well documented. The present study was designed to investigate the impact of BM in the CDL and on…

  18. The Bolund experiment: Overview and background; Wind conditions in complex terrain

    Energy Technology Data Exchange (ETDEWEB)

    Bechmann, A.; Berg, J.; Courtney, M.S.; Joergensen, Hans E.; Mann, J.; Soerensen, Niels N.

    2009-07-15

    The Bolund experiment is a measuring campaign performed in 2007 and 2008. The aim of the experiment is to measure the flow field around the Bolund hill in order to provide a dataset for validating numerical flow models. The present report gives an overview of the whole experiment including a description of the orography, the instrumentation used and of the data processing. The Actual measurements are available from a database also described. (au)

  19. The role of background music in the experience of watching YouTube videos about death and dying

    Directory of Open Access Journals (Sweden)

    Panagiotis Pentaris

    2015-12-01

    Full Text Available YouTube is the largest video sharing site live at the moment. It has been used to communicate a vast array of information, while it allows for user-generated content. This paper will focus on YouTube videos that communicate death, and in particular will present findings from a preliminary study undertaken by the authors considering the role that background music plays in these videos. Specifically, this study explores the experiences of the viewers of death-related YouTube videos with and without background music while it makes comparisons in relation to the impact that music has on the viewers’ emotional experiences. We conclude that background music elicits emotions and enhances feelings of sadness and sympathy in relation to the visual content of videos while recommendations for future research are made.

  20. Observations of the anisotropy in the cosmic microwave background by the FIRS, SK93, and MSAM-I experiments

    Science.gov (United States)

    Kowitt, Matt; Cheng, Ed; Silverberg, Bob; Ganga, Ken; Page, Lyman; Jarosik, Norm; Netterfield, Barth; Wilkinson, Dave; Meyer, Stephan; Inman, Casey; hide

    1994-01-01

    The observations and results from the FIRS, SK93, and MSAM-1, experiments are discussed. These experiments search for anisotropy in the cosmic microwave background over a range in angular scale from 180 deg to 0.5 deg and a range in frequency from 26 to 680 GHz. Emphasis is placed on the observing strategy and potential systematic errors. Contamination of the data by galactic sources is addressed. Future directions are indicated. The results for all three experiments, as found by us and others, are given in the context of the standard CDM model, Q(sub CDM), and the model-independent band-power estimates.

  1. LHCb: Beam and Background Monitoring and the Development of an Online Condition Analysis Tool for the LHCb Experiment at CERN

    CERN Multimedia

    Alessio, F

    2010-01-01

    The LHCb experiment has been taking data since more than half a year at the LHC, recording events from collisions at the highest energy ever achieved. For its physics purposes in the sector of CP violation, the experiment will record data with the best precision achievable. An online and offline beam and background monitoring became therefore essential to understand the performance of the LHC accelerator at CERN, to monitor and study the behavior of the background around the LHCb experiment and to optimize the experimental conditions. During my second year as a Doctoral Student at CERN, I have been working on the timing and readout control as well as on the online Beam, Background, and Luminosity Monitoring of the LHCb experiment in the frame of the LHCb Online group. The group is responsible for the complete data acquisition of the LHCb experiment, from the Front-End Electronics (FEE) to the storage of the data for offline analysis, including the Timing and Fast Control (TFC) system. The latter controls and...

  2. The Relationship of a Pilot's Educational Background, Aeronautical Experience and Recency of Experience to Performance In Initial Training at a Regional Airline

    Science.gov (United States)

    Shane, Nancy R.

    The purpose of this study was to determine how a pilot's educational background, aeronautical experience and recency of experience relate to their performance during initial training at a regional airline. Results show that variables in pilots' educational background, aeronautical experience and recency of experience do predict performance in training. The most significant predictors include years since graduation from college, multi-engine time, total time and whether or not a pilot had military flying experience. Due to the pilot shortage, the pilots entering regional airline training classes since August 2013 have varied backgrounds, aeronautical experience and recency of experience. As explained by Edward Thorndike's law of exercise and the law of recency, pilots who are actively using their aeronautical knowledge and exercising their flying skills should exhibit strong performance in those areas and pilots who have not been actively using their aeronautical knowledge and exercising their flying skills should exhibit degraded performance in those areas. Through correlation, chi-square and multiple regression analysis, this study tests this theory as it relates to performance in initial training at a regional airline.

  3. The Psychologist's Troubled Background: Major Related Life Experiences of Psychology and Law Students

    Science.gov (United States)

    Werz, Janina; Buechner, Vanessa L.

    2017-01-01

    This study explores major-related life experiences (MRLE) of psychology and law students to examine the stereotype of the wounded psychology student. Previous studies have shown that psychology students know people with mental disorders and are seeking treatment themselves. However, these studies do not allow drawing conclusions about the…

  4. Cursus Honorum: Personal Background, Careers and Experience of Political Leaders in Democracy and Dictatorship—New Data and Analyses

    Directory of Open Access Journals (Sweden)

    Alexander Baturo

    2016-06-01

    Full Text Available Politics in democracy and dictatorship is markedly different; democracy and dictatorship are also associated with distinct policy outcomes. Do political regimes also select different leaders, i.e., do democratic leaders have distinct personal backgrounds to those of their peers in dictatorships, do they tend to hold different prior careers and posts while climbing the “greasy pole” of politics? The aim of this paper is to introduce the new data on leaders’ careers in democracy and dictatorship and compare their personal background, experience in politics, careers and significant posts prior to their tenure, and details about their time in office, inter alia. In general, democratic leaders differ from nondemocratic ones in terms of their educational, social and career background. The paper also finds significant differences among leaders in different nondemocratic regimes, and suggests possible venues for further research.

  5. Background on the commercial explosive chosen for the non-proliferation experiment

    Energy Technology Data Exchange (ETDEWEB)

    Mammele, M.E.

    1994-12-31

    The requirements of the Chemical Kiloton Experiment as outlined in the original explosives bid package provided DYNO NOBEL/Alpha-Ireco, Inc. with a unique challenge. The size of the chamber, the total volume of explosives required, the chemical energy equivalent of one kiloton, the time-frame of loading the chamber, transportation, safety, were all necessary considerations in choosing this particular explosive. The rationale for choosing this particular emulsion/ANFO blend of blasting agent explosive will be presented. DYNO NOBEL INC in-house theoretical predictions as to the explosive performance potential of the blasting agent will be compared to some of the actual data acquired upon detonation. The results of this type of experiment may provide new insight as to the efficiency of the energy release of typical commercial explosives.

  6. Experiences of registered nurses from a refugee background: A scoping review.

    Science.gov (United States)

    Ng Chok, Harrison; Mannix, Judy; Dickson, Cathy; Wilkes, Lesley

    2018-04-01

    This scoping review presents an exploration of international literature on the factors that impact refugees' personal and professional experiences during their journey to being registered nurses in a new host country. Governments of host countries receiving refugees seek to develop strategies that facilitate the successful resettlement, employment and enculturation of refugees that arrive as skilled professionals. There is a scarcity of studies focussing on issues faced by refugees that are RNs or those pursuing nursing registration and employment in a new host country. This study is relevant for resettlement services, nursing registration authorities and education providers and informs the international nursing workforce. Scoping review. Databases such as MEDLINE, EMBASE, Cochrane Library, CINAHL; Google Scholar; PubMed; Scopus and Web of Science were searched for qualitative studies published up to and including 2017. Articles that did not specify explicitly the participants as registered nurses and/or refugees were excluded. All eligible articles were analysed for collective findings, and impact factors were extracted, synthesised and illustrated diagrammatically. This review explored six eligible articles and six impact factors were identified. The challenging impacts were as follows: loss of control; shock in a new environment and bleak employment prospects. Equally three impact factors: reconciling new reality; establishing a new identity and hope for the future, facilitate positive experiences for nurses in their successful transition into society and the nursing workplace. This scoping review reports the small number of international studies on the experiences of refugees seeking to become registered and employed as registered nurses. The six impact factors identified influence the lives of the nurse participants socio-economically in and out of the workplace. Policymakers, managers and educators providing resettlement, registration and employment services

  7. Investigation of the muon-induced background of the EDELWEISS-II experiment

    International Nuclear Information System (INIS)

    Chantelauze, A.

    2009-11-01

    The EDELWEISS experiment aims at detecting WIMPs (weakly interactive massive particles) which could possibly amount for all or part of the dark matter in the universe. It measures the energy released by nuclear recoils produced by the elastic collision of a WIMP in an ordinary matter target. Due to the very small interaction cross-section of WIMP with nucleons, which leads to an extremely low expected event rate ( R < 250 keV. (author)

  8. Study of the material photon and electron background and the liquid argon detector veto efficiency of the CDEX-10 experiment

    International Nuclear Information System (INIS)

    Su Jian; Zeng Zhi; Ma Hao

    2015-01-01

    The China Dark Matter Experiment (CDEX) is located at the China Jinping Underground Laboratory (CJPL) and aims to directly detect the weakly interacting massive particles (WIMP) flux with high sensitivity in the low mass region. Here we present a study of the predicted photon and electron backgrounds including the background contribution of the structure materials of the germanium detector, the passive shielding materials, and the intrinsic radioactivity of the liquid argon that serves as an anti-Compton active shielding detector. A detailed geometry is modeled and the background contribution has been simulated based on the measured radioactivities of all possible components within the GEANT4 program. Then the photon and electron background level in the energy region of interest (< 10 -2 events·kg 1 ·day -1 ·keV -1 (cpkkd)) is predicted based on Monte Carlo simulations. The simulated result is consistent with the design goal of the CDEX-10 experiment, 0.1cpkkd, which shows that the active and passive shield design of CDEX-10 is effective and feasible. (authors)

  9. The effect of a scanning flat fold mirror on a cosmic microwave background B-mode experiment.

    Science.gov (United States)

    Grainger, William F; North, Chris E; Ade, Peter A R

    2011-06-01

    We investigate the possibility of using a flat-fold beam steering mirror for a cosmic microwave background B-mode experiment. An aluminium flat-fold mirror is found to add ∼0.075% polarization, which varies in a scan synchronous way. Time-domain simulations of a realistic scanning pattern are performed, and the effect on the power-spectrum illustrated, and a possible method of correction applied. © 2011 American Institute of Physics

  10. Characterization, 1064 nm photon signals and background events of a tungsten TES detector for the ALPS experiment

    International Nuclear Information System (INIS)

    Dreyling-Eschweiler, J.; Doebrich, B.; Januschek, F.; Lindner, A.; Bastidon, N.; Horns, D.

    2015-02-01

    The high efficiency, low-background, and single-photon detection with transition-edge sensors (TES) is making this type of detector attractive in widely different types of application. In this paper, we present first characterizations of a TES to be used in the Any Light Particle Search (ALPS) experiment searching for new fundamental ultra-light particles. Firstly, we describe the setup and the main components of the ALPS TES detector (TES, millikelvin-cryostat and SQUID read-out) and their performances. Secondly, we explain a dedicated analysis method for single-photon spectroscopy and rejection of non-photon background. Finally, we report on results from extensive background measurements. Considering an event-selection, optimized for a wavelength of 1064 nm, we achieved a background suppression of ∝10 -3 with a ∝ 50 % efficiency for photons passing the selection. The resulting overall efficiency was 23 % with a dark count rate of 8.6.10 -3 s -1 . We observed that pile-up events of thermal photons are the main background component.

  11. Measurement of Radon-Induced Backgrounds in the NEXT Double Beta Decay Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Novella, P.; et al.

    2018-04-02

    The measurement of the internal 222Rn activity in the NEXT-White detector during the so-called Run-II period with 136Xe-depleted xenon is discussed in detail, together with its implications for double beta decay searches in NEXT. The activity is measured through the alpha production rate induced in the fiducial volume by 222Rn and its alpha-emitting progeny. The specific activity is measured to be $(37.5\\pm 2.3~\\mathrm{(stat.)}\\pm 5.9~\\mathrm{(syst.)})$~mBq/m$^3$. Radon-induced electrons have also been characterized from the decay of the 214Bi daughter ions plating out on the cathode of the time projection chamber. From our studies, we conclude that radon-induced backgrounds are sufficiently low to enable a successful NEXT-100 physics program, as the projected rate contribution should not exceed 0.2~counts/yr in the neutrinoless double beta decay sample.

  12. Probing the Underground Science beyond the Standard Model with Ultra-Low Background Experiments at Sanford Lab/DUSEL

    International Nuclear Information System (INIS)

    Mei, D.-M.

    2010-01-01

    We show that an improved sensitivity on effective neutrino mass to the atmospheric neutrino mass scale with the next generation germanium-based double-beta decay experiment together with results from cosmology survey, θ 13 measurements and neutrino oscillation experiments may be able to determine the absolute mass scale of the neutrino, and answer the question of the neutrino nature. To achieve such a sensitivity of 45 meV, the next generation germanium experiment must reduce background by a factor of 440 comparing to the existing results. The planned germanium experiment at the Deep Underground Science and Engineering Laboratory (DUSEL) in western South Dakota aims at achieving such a sensitivity. Sanford Lab supported by the state of South Dakota and a private donor, Mr. T. Denny Sanford, will be up and running within the next year to pave the way for the creation of DUSEL in five years.

  13. Poloidal magnetic field profile measurements on the microwave tokamak experiment using far-infrared polarimetry

    International Nuclear Information System (INIS)

    Rice, B.W.

    1992-09-01

    The measurement of plasma poloidal magnetic field (B) profiles in tokamaks with good temporal and spatial resolution has proven to be a difficult but important measurement. A large range of toroidal confinement phenomena is expected to depend sensitively on the radial variation of B including the tearing instability, sawtooth oscillations, disruptions, and transport. Experimental confirmation of theoretical models describing these phenomena has been hampered by the lack of detailed B measurements. A fifteen chord far-infrared (FIR) polarimeter has been developed to measure B in the Microwave Tokamak, Experiment (MTX). Polarimetry utilizes the well known Faraday rotation effect, which causes a rotation of the polarization of an FIR beam propagating in the poloidal plane. The rotation angle is proportional to the component of B parallel to the beam. A new technique for determining the Faraday rotation angle is introduced, based on phase measurements of a rotating polarization ellipse. This instrument has been used successfully to measure B profiles for a wide range of experiments on MTX. For ohmic discharges, measurements of the safety factor on axis give q 0 ∼ 0.75 during sawteeth and q 0 > 1 without sawteeth. Large perturbations to the polarimeter signals correlated with the sawtooth crash are observed during some discharges. Measurements in discharges with electron cyclotron heating (ECH) show a transition from a hollow to peaked J profile that is triggered by the ECH pulse. Current-ramp experiments were done to perturb the J profile from the nominal Spitzer conductivity profile. Profiles for initial current ramps and ramps starting from a stable equilibrium have been measured and are compared with a cylindrical diffusion model. Finally, the tearing mode stability equation is solved using measured J profiles. Stability predictions are in good agreement with the existence of oscillations observed on the magnetic loops

  14. Measuring fast neutrons with large liquid scintillation detector for ultra-low background experiments

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, C. [Department of Physics, The University of South Dakota, Vermillion, SD 57069 (United States); College of Sciences, China Three Gorges University, Yichang 443002 (China); Mei, D.-M., E-mail: dongming.mei@usd.edu [Department of Physics, The University of South Dakota, Vermillion, SD 57069 (United States); Davis, P.; Woltman, B. [Department of Physics, The University of South Dakota, Vermillion, SD 57069 (United States); Gray, F. [Department of Physics and Computational Science, Regis University, Denver, CO 80221 (United States)

    2013-11-21

    We developed a 12-liter volume neutron detector filled with the liquid scintillator EJ301 that measures neutrons in an underground laboratory where dark matter and neutrino experiments are located. The detector target is a cylindrical volume coated on the inside with reflective paint (95% reflectivity) that significantly increases the detector's light collection. We demonstrate several calibration techniques using point sources and cosmic-ray muons for energies up to 20 MeV for this large liquid scintillation detector. Neutron–gamma separation using pulse shape discrimination with a few MeV neutrons to hundreds of MeV neutrons is shown for the first time using a large liquid scintillator.

  15. Design and Operation of Cryogenic Distillation Research Column for Ultra-Low Background Experiments

    Science.gov (United States)

    Chiller, Christopher; Alanson Chiller, Angela; Jasinski, Benjamin; Snyder, Nathan; Mei, Dongming

    2013-04-01

    Motivated by isotopically enriched germanium (76Ge and 73Ge) for monocrystalline crystal growth for neutrinoless double-beta decay and dark matter experiments, a cryogenic distillation research column was developed. Without market availability of distillation columns in the temperature range of interest with capabilities necessary for our purposes, we designed, fabricated, tested, refined and operated a two-meter research column for purifying and separating gases in the temperature range from 100-200K. Due to interest in defining stratification, purity and throughput optimization, capillary lines were integrated at four equidistant points along the length of the column such that real-time residual gas analysis could guide the investigation. Interior gas column temperatures were monitored and controlled within 0.1oK accuracy at the top and bottom. Pressures were monitored at the top of the column to four significant figures. Subsequent impurities were measured at partial pressures below 2E-8torr. We report the performance of the column in this paper.

  16. Differences between previously married and never married 'gay' men: family background, childhood experiences and current attitudes.

    Science.gov (United States)

    Higgins, Daryl J

    2004-01-01

    Despite a large body of literature on the development of sexual orientation, little is known about why some gay men have been (or remain) married to a woman. In the current study, a self-selected sample of 43 never married gay men ('never married') and 26 gay men who were married to a woman ('previously married') completed a self-report questionnaire. Hypotheses were based on five possible explanations for gay men's marriages: (a) differences in sexual orientation (i.e., bisexuality); (b) internalized homophobia; (c) religious intolerance; (d) confusion created because of childhood/adolescent sexual experiences; and/or (e) poor psychological adjustment. Previously married described their families' religious beliefs as more fundamentalist than never married. No differences were found between married' and never married' ratings of their sexual orientation and identity, and levels of homophobia and self-depreciation. Family adaptability and family cohesion and the degree to which respondents reported having experienced child maltreatment did not distinguish between previously married and never married. The results highlight how little is understood of the reasons why gay men marry, and the need to develop an adequate theoretical model.

  17. The Experiences of Israeli Early Childhood Educators Working With Children of Ethiopian Background

    Directory of Open Access Journals (Sweden)

    Esther Firstater

    2015-09-01

    Full Text Available This study offers an in-depth examination of the experiences of early childhood educators, focusing on their work with Ethiopian immigrant children and their families. We aim to describe and analyze the teachers’ insider views vis-à-vis the challenges faced by these children and their parents in the Israeli preschool system. Using narrative methodology, the analysis of findings is based upon 20 stories written by 10 early childhood educators. It reveals that for these teachers, the chief struggle is their relationship with the parents of their Ethiopian pupils, one characterized by difficulties, frustrations, and burdens. The engagement with parents of Ethiopian children exhibited a range of possibilities: from the expression of patronizing, hierarchical viewpoints, to a search for ad hoc ways of coping with a persistent cultural gap, to the attainment of genuine, successful partnerships. Lack of sufficient knowledge and understanding of the unique cultural attributes of the Ethiopian community appears to be the basis for the teachers’ view of the parents as lacking faith in them and in the educational system as a whole. In addition, suggestions are made about implications for educational practice and for policies that might assist teachers in ameliorating these challenges via the development of, and professional training in, skills which help coping with the problems and dilemmas unique to the multicultural classroom.

  18. Simulations of the muon-induced neutron background of the EDELWEISS-II experiment for Dark Matter search

    International Nuclear Information System (INIS)

    Horn, O.M.

    2007-01-01

    In modern astroparticle physics and cosmology, the nature of Dark Matter is one of the central problems. Particle Dark Matter in form of WIMPs is favoured among many proposed candidates. The EDELWEISS direct Dark Matter search uses Germanium bolometers to detect these particles by nuclear recoils. Here, the use of two signal channels on an event-by-event basis, namely the heat and ionisation signal, enables the detectors to discriminate between electron and nuclear recoils. This technique leaves neutrons in the underground laboratory as the main background for the experiment. Besides (α,n) reactions of natural radioactivity, neutrons are produced in electromagnetic and hadronic showers induced by cosmic ray muons in the surrounding rock and shielding material of the Germanium crystals. To reach high sensitivities, the EDELWEISS-II experiment, as well as other direct Dark Matter searches, has to efficiently suppress this neutron background. The present work is devoted to study the muon-induced neutron flux in the underground laboratory LSM and the interaction rate within the Germanium crystals by using the Monte Carlo simulation toolkit Geant4. To ensure reliable results, the implemented physics in the toolkit regarding neutron production is tested in a benchmark geometry and results are compared to experimental data and other simulation codes. Also, the specific energy and angular distribution of the muon flux in the underground laboratory as a consequence of the asymmetric mountain overburden is implemented. A good agreement of the simulated muon flux is shown in a comparison to preliminary experimental data obtained with the EDELWEISS-II muon veto system. Furthermore, within a detailed geometry of the experimental setup, the muon-induced background rate of nuclear recoils in the bolometers is simulated. Coincidences of recoil events in the Germanium with an energy deposit of the muoninduced shower in the plastic scintillators of the veto system are studied to

  19. Simulations of the muon-induced neutron background of the EDELWEISS-II experiment for Dark Matter search

    Energy Technology Data Exchange (ETDEWEB)

    Horn, O M

    2007-12-21

    In modern astroparticle physics and cosmology, the nature of Dark Matter is one of the central problems. Particle Dark Matter in form of WIMPs is favoured among many proposed candidates. The EDELWEISS direct Dark Matter search uses Germanium bolometers to detect these particles by nuclear recoils. Here, the use of two signal channels on an event-by-event basis, namely the heat and ionisation signal, enables the detectors to discriminate between electron and nuclear recoils. This technique leaves neutrons in the underground laboratory as the main background for the experiment. Besides ({alpha},n) reactions of natural radioactivity, neutrons are produced in electromagnetic and hadronic showers induced by cosmic ray muons in the surrounding rock and shielding material of the Germanium crystals. To reach high sensitivities, the EDELWEISS-II experiment, as well as other direct Dark Matter searches, has to efficiently suppress this neutron background. The present work is devoted to study the muon-induced neutron flux in the underground laboratory LSM and the interaction rate within the Germanium crystals by using the Monte Carlo simulation toolkit Geant4. To ensure reliable results, the implemented physics in the toolkit regarding neutron production is tested in a benchmark geometry and results are compared to experimental data and other simulation codes. Also, the specific energy and angular distribution of the muon flux in the underground laboratory as a consequence of the asymmetric mountain overburden is implemented. A good agreement of the simulated muon flux is shown in a comparison to preliminary experimental data obtained with the EDELWEISS-II muon veto system. Furthermore, within a detailed geometry of the experimental setup, the muon-induced background rate of nuclear recoils in the bolometers is simulated. Coincidences of recoil events in the Germanium with an energy deposit of the muoninduced shower in the plastic scintillators of the veto system are studied

  20. Study of rare neutron induced processes and coincidence analyses to identify and reduce background contributions in the COBRA experiment

    International Nuclear Information System (INIS)

    Timm, Jan Horst Karl

    2015-11-01

    The aim of the COBRA experiment is the observation of neutrinoless double-beta decay, primarily of the isotope 116 Cd. The applied semiconductor detectors of cadmium zinc telluride that are 90% to be enriched enable both the detection and the source of this decay. The half-lives of decays of this kind are expected in the range of more than 10 26 years. Therefore, the reduction of contributions to the background is of decisive importance. The main subjects of this work are, on the one hand, the time synchronization of the data, which provides the basis for coincidence analysis. This analysis method has access not only to identification of contributions to the background, but also to observe decays involving positron annihilation and decays into excited states. In this study, the intrinsic detector contamination of some decay products of 238 U and 232 Th was measured and sensitivities to the half-lives of the decays like 120 Te and 128 Te in each case to the first excited state of daughter products are given. On the other hand, qualitative studies on the importance of neutrons in the COBRA experiment were conducted. These have shown that fast neutrons, thus with energies greater than 10 keV, only result in an insignificant contribution to the background for the detection of neutrinoless double-beta decay of the 116 Cd. Previous studies have also shown that the thermal neutron flux can be in situ determined by coincidence analysis.

  1. Emergence of a signal from background noise in the "memory of water" experiments: how to explain it?

    Science.gov (United States)

    Beauvais, Francis

    2012-01-01

    After more than 20 years, the case of the "memory of water" still has not been resolved satisfactorily. After the affair with the journal Nature, Benveniste extended his results on high dilutions to an "electromagnetic biology" and then to a "digital biology," where electromagnetic signals supposed to be emitted from biologically active solutions were said to be stored on magnetic memories. Although the results obtained by Benveniste and coworkers were obvious, the difficulties in reproducibility by other teams created doubt of the reality of the alleged phenomenon. In a first step, we analyzed a set of experiments obtained by Benveniste's team in the 1990s. We quantified the relationship between "expected" effects (ie, labels of the tested samples) and apparatus outcomes, and we defined the experimental conditions to observe significant correlations. We concluded that the results of these experiments were related to experimenter-dependent correlations, which did not support the initial "memory of water" hypothesis. The fact that a signal emerged from background noise, however, remained puzzling. Therefore, in a second step, we described Benveniste's experiments according to the relational interpretation of quantum physics of C. Rovelli. In this interpretation, the state of a system is observer-dependent and the collapse of the wave function appears only in the states relative to a given observer. This interpretation allowed us to elaborate a model describing Benveniste's experiments in which the emergence of a signal from background noise was described by the entanglement of the experimenter with the observed system. In conclusion, the pursuit of the experimental "proof" to support the "memory of water" hypothesis has prevented other interpretations. Although our hypothesis does not definitely dismiss the possibility of "memory of water," the experimenter-dependent entanglement could be an attractive alternative interpretation of Benveniste's experiments

  2. Time-resolved far-infrared experiments at the National Synchrotron Light Source. Final report

    International Nuclear Information System (INIS)

    Tanner, D.B.; Reitze, D.H.; Carr, G.L.

    1999-01-01

    A facility for time-resolved infrared and far-infrared spectroscopy has been built and commissioned at the National Synchrotron Light Source. This facility permits the study of time dependent phenomena over a frequency range from 2-8000cm -1 (0.25 meV-1 eV). Temporal resolution is approximately 200 psec and time dependent phenomena in the time range out to 100 nsec can be investigated

  3. The role of background music in the experience of watching YouTube videos about death and dying

    OpenAIRE

    Panagiotis Pentaris; Maria Yerosimou

    2015-01-01

    YouTube is the largest video-sharing site live at the moment. It has been used to communicate a vast array of information, while it allows for user-generated content. This paper will focus on YouTube videos that communicate death, and, in particular, will present findings from a preliminary study undertaken by the authors considering the role that background music plays in these videos. Specifically, this study explores the experiences of the viewers of death-related YouTube videos with and w...

  4. DAQ Software Contributions, Absolute Scale Energy Calibration and Background Evaluation for the NOvA Experiment at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Flumerfelt, Eric Lewis [Univ. of Tennessee, Knoxville, TN (United States)

    2015-08-01

    The NOvA (NuMI Off-axis ve [nu_e] Appearance) Experiment is a long-baseline accelerator neutrino experiment currently in its second year of operations. NOvA uses the Neutrinos from the Main Injector (NuMI) beam at Fermilab, and there are two main off-axis detectors: a Near Detector at Fermilab and a Far Detector 810 km away at Ash River, MN. The work reported herein is in support of the NOvA Experiment, through contributions to the development of data acquisition software, providing an accurate, absolute-scale energy calibration for electromagnetic showers in NOvA detector elements, crucial to the primary electron neutrino search, and through an initial evaluation of the cosmic background rate in the NOvA Far Detector, which is situated on the surface without significant overburden. Additional support work for the NOvA Experiment is also detailed, including DAQ Server Administration duties and a study of NOvA’s sensitivity to neutrino oscillations into a “sterile” state.

  5. Infrared observation of the early universe

    International Nuclear Information System (INIS)

    Matsumoto, T.

    1984-01-01

    The rocket observation of the near-infrared extragalactic background radiation and its influence on the cosmology are described. The furute plans to observe the near-infrared and far-infrared backgrounds are also presented. (author)

  6. Effect of metal stress on the thermal infrared emission of soybeans: A greenhouse experiment - Possible utility in remote sensing

    Science.gov (United States)

    Suresh, R.; Schwaller, M. R.; Foy, C. D.; Weidner, J. R.; Schnetzler, C. S.

    1989-01-01

    Manganese-sensitive forest and manganese-tolerant lee soybean cultivars were subjected to differential manganese stress in loring soil in a greenhouse experiment. Leaf temperature measurements were made using thermistors for forest and lee. Manganese-stressed plants had higher leaf temperatures than control plants in both forest and lee. Results of this experiment have potential applications in metal stress detection using remote sensing thermal infrared data over large areas of vegetation. This technique can be useful in reconnaissance mineral exploration in densely-vegetated regions where conventional ground-based methods are of little help.

  7. Neutron-induced Backgrounds in 134Xe for Large-Scale Neutrinoless Double-Beta Decay Experiments

    Science.gov (United States)

    Moriguchi, Nina; Kidd, Mary; Tornow, Werner

    2016-09-01

    136Xe is used in large neutrinoless double-beta (0 νββ) decay experiments, such as KamLAND- Zen and EXO 200. Though highly purified, 136Xe still contains a significant amount of 134Xe. Recently, a new nuclear energy level was found in 134Xe. If 134Xe decays from this proposed excited state, it will emit a 2485.7 keV gamma ray. Because this energy lies near the region of interest of 136Xe νββ decay experiments (Q value 2457.8 keV), it could make a significant contribution to the background. A purified gaseous sample of 134Xe will be irradiated with neutrons of an incident energy of 4.0 MeV at Triangle Universities Nuclear Laboratory and monitored with high-purity germanium detectors. The spectra obtained from these detectors will be analyzed for the presence of the 2581 keV gamma ray. We will report on the status of this experiment. Future plans include expanding this measurement to higher initial neutron energies. Tennesse Tech University CISE Grant program.

  8. High Frequency Propagation modeling in a disturbed background ionosphere: Results from the Metal Oxide Space Cloud (MOSC) experiment

    Science.gov (United States)

    Joshi, D. R.; Groves, K. M.

    2015-12-01

    The Air Force Research Laboratory (AFRL) launched two sounding rockets in the Kwajalein Atoll, Marshall Islands, in May 2013 known as the Metal Oxide Space Cloud (MOSC) experiment to study the interactions of artificial ionization and the background plasma. The rockets released samarium metal vapor in the lower F-region of the ionosphere that ionized forming a plasma cloud. A host of diagnostic instruments were used to probe and characterize the cloud including the ALTAIR incoherent scatter radar, multiple GPS and optical instruments, satellite radio beacons, and a dedicated network of high frequency (HF) radio links. Data from ALTAIR incoherent scatter radar and HF radio links have been analyzed to understand the impacts of the artificial ionization on radio wave propagation. During the first release the ionosphere was disturbed, rising rapidly and spread F formed within minutes after the release. To address the disturbed conditions present during the first release, we have developed a new method of assimilating oblique ionosonde data to generate the background ionosphere that can have numerous applications for HF systems. The link budget analysis of the received signals from the HF transmitters explains the missing low frequencies in the received signals along the great circle path. Observations and modeling confirm that the small amounts of ionized material injected in the lower-F region resulted in significant changes to the natural propagation environment.

  9. The water purification system for the low background counting test facility of the Borexino experiment at Gran Sasso

    International Nuclear Information System (INIS)

    Balata, M.; Cadonati, L.; Laubenstein, M.; Heusser, G.; Giammarchi, M.G.; Scardaoni, R.; Torri, V.; Cecchet, G.; De Bari, A.; Perotti, A.

    1996-01-01

    The Borexino experiment, for the study of solar neutrino physics, requires radiopurity at the level of 5 x 10 -16 g/g 238 U equivalent (or 6 x 10 -9 Bq/kg) on a detector mass of many tons of scintillator. Feasibility studies are performed in a counting test facility now operating at LNGS, which consists of 4 t of liquid scintillator viewed by 100 photomultipliers and shielded by 100 t of water. The accomplishment of this goal requires the shielding liquid, water, to be at the 10 -13 g/g contamination level (1.2 x 10 -6 Bq/kg) or better. This paper describes the water purification system; it consists of a combination of several purification processes to remove particulate, radioactive ions, dissolved gases and other impurities. Residual contaminations are measured by analytical or direct-counting techniques. For radon measurement, particularly challenging at this low activity levels, a low background counting method has been developed. (orig.)

  10. Simulation studies of muon-produced background events deep underground and consequences for double beta decay experiments

    Science.gov (United States)

    Massarczyk, Ralph; Majorana Collaboration

    2015-10-01

    Cosmic radiation creates a significant background for low count rate experiments. The Majorana demonstrator experiment is located at the Sanford Underground Research Facility at a depth of 4850ft below the surface but it can still be penetrated by cosmic muons with initial energies above the TeV range. The interaction of muons with the rock, the shielding material in the lab and the detector itself can produce showers of secondary particles, like fast neutrons, which are able to travel through shielding material and can produce high-energy γ-rays via capture or inelastic scattering. The energy deposition of these γ rays in the detector can overlap with energy region of interest for the neutrino-less double beta decay. Recent studies for cosmic muons penetrating the Majorana demonstrator are made with the Geant4 code. The results of these simulations will be presented in this talk and an overview of the interaction of the shower particles with the detector, shielding and veto system will be given. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, the Particle Astrophysics Program of the National Science Foundation, and the Sanford Underground Research Facility. Supported by U.S. Department of Energy through the LANL/LDRD Program.

  11. Background experiences, time allocation, time on teaching and perceived support of early-career college science faculty

    Science.gov (United States)

    Sagendorf, Kenneth S.

    The purposes of this research were to create an inventory of the research, teaching and service background experiences of and to document the time allocation and time spent on teaching by early-career college science faculty members. This project is presented as three distinct papers. Thirty early-career faculty in the science disciplines from sixteen different institutions in their first year of employment participated in this study. For the first two papers, a new survey was developed asking participants to choose which experiences they had acquired prior to taking their current faculty position and asking them to document their time allocation and time spent on teaching activities in an average work week. In addition, a third component documents the support early-career college faculty in the sciences are receiving from the perspective of faculty members and their respective department chairpersons and identifies areas of disagreement between these two different groups. Twenty early-career college science faculty and their respective department chairpersons completed a newly-designed survey regarding the support offered to new faculty. The survey addressed the areas of feedback on performance, clarity of tenure requirements, mentoring, support for teaching and scholarship and balancing faculty life. This dissertation presents the results from these surveys, accounting for different demographic variables such as science discipline, gender and institutional category.

  12. Extinction of visible and infrared radiation in rain Comparison of theory and experiment

    Science.gov (United States)

    Ulbrich, C. W.; Atlas, D.

    1985-01-01

    A critical review is given of the experimental and theoretical results concerning the measurement of rainfall using optical extinction, i.e., the attenuation of radiation with wavelength less than or equal to that of the infrared band. It is shown that rainfall rates found from an empirical relation involving optical extinction generally display average deviations without regard for sign of only 25 percent when compared with those measured by raingages directly beneath the optical beam. It is also shown that the differences between experimental and theoretical results can be explained in terms of variations of the shape of the raindrop size distribution, i.e., deviations from exponentiality.

  13. Contribution to the G0 experiment about parity violation: calculation and simulation of radiative corrections, study of the background noise

    International Nuclear Information System (INIS)

    Guler, H.

    2003-12-01

    In the framework of quantum chromodynamics, the nucleon is made of three valence quarks surrounded by a sea of gluons and quark-antiquark pairs. Only the only lightest quarks (u, d and s) contribute significantly to the nucleon properties. In G 0 we use the property of weak interaction to violate parity symmetry, in order to determine separately the contributions of the three types of quarks to nucleon form factors. The experiment, which takes place at Thomas Jefferson laboratory (USA), aims at measuring parity violation asymmetry in electron-proton scattering. By doing several measurements at different momentum squared of the exchanged photons and for different kinematics (forward angle when the proton is detected and backward angle it will be the electron) will permit to determine separately strange quarks electric and magnetic contributions to nucleon form factors. To extract an asymmetry with small errors, it is necessary to correct all the beam parameters, and to have high enough counting rates in detectors. A special electronics was developed to treat information coming from 16 scintillator pairs for each of the 8 sectors of the G 0 spectrometer. A complete calculation of radiative corrections has been done and Monte Carlo simulations with the GEANT program has permitted to determine the shape of the experimental spectra including inelastic background. This work will allow to do a comparison between experimental data and theoretical calculations based on the Standard Model. (author)

  14. Development of High Frequency Transition-Edge-Sensor Polarimeters for Next Generation Cosmic Microwave Background Experiments and Galactic Foreground Measurements

    Science.gov (United States)

    Walker, Samantha; Sierra, Carlos E.; Austermann, Jason Edward; Beall, James; Becker, Dan; Dober, Bradley; Duff, Shannon; Hilton, Gene; Hubmayr, Johannes; Van Lanen, Jeffrey L.; McMahon, Jeff; Simon, Sara M.; Ullom, Joel; Vissers, Michael R.; NIST Quantum Sensors Group

    2018-06-01

    Observations of the cosmic microwave background (CMB) provide a powerful tool for probing the earliest moments of the universe and therefore have the potential to transform our understanding of cosmology. In particular, precision measurements of its polarization can reveal the existence of gravitational waves produced during cosmic inflation. However, these observations are complicated by the presence of astrophysical foregrounds, which may be separated by using broad frequency coverage, as the spectral energy distribution between foregrounds and the CMB is distinct. For this purpose, we are developing large-bandwidth, feedhorn-coupled transition-edge-sensor (TES) arrays that couple polarized light from waveguide to superconducting microstrip by use of a symmetric, planar orthomode transducer (OMT). In this work, we describe two types of pixels, an ultra-high frequency (UHF) design, which operates from 195 GHz-315 GHz, and an extended ultra-high frequency (UHF++) design, which operates from 195 GHz-420 GHz, being developed for next generation CMB experiments that will come online in the next decade, such as CCAT-prime and the Simons Observatory. We present the designs, simulation results, fabrication, and preliminary measurements of these prototype pixels.

  15. Acupuncture or low frequency infrared treatment for low back pain in Chinese patients: a discrete choice experiment.

    Directory of Open Access Journals (Sweden)

    Li-Chia Chen

    Full Text Available Acupuncture is a popular but controversial treatment option for low back pain. In China, it is practised as traditional Chinese medicine; other treatment strategies for low back pain are commonly practised as Western medicine. Research on patient preference for low back-pain treatment options has been mainly conducted in Western countries and is limited to a willingness-to-pay approach. A stated-preference, discrete choice experiment was conducted to determine Chinese patient preferences and trade-offs for acupuncture and low frequency infrared treatment in low back pain from September 2011 to August 2012 after approval from the Department of Scientific Research in the study settings. Eight-six adult outpatients who visited the 'traditional medicine department' at a traditional Chinese medicine hospital and the 'rehabilitation department' at a Western medicine hospital in Guangdong Province of China for chronic low back pain during study period participated in an interview survey. A questionnaire containing 10 scenarios (5 attributes in each scenario was used to ask participants' preference for acupuncture, low frequency infrared treatment or neither option. Validated responses were analysed using a nested-logit model. The decision on whether to receive a therapy was not associated with the expected utility of receiving therapy, female gender and higher out-of-pocket payment significantly decreased chance to receive treatments. Of the utility of receiving either acupuncture or low frequency infrared treatment, the treatment sensation was the most important attribute as an indicator of treatment efficacy, followed by the maximum efficacy, maintenance duration and onset of efficacy, and the out-of-pocket payment. The willingness-to-pay for acupuncture and low frequency infrared treatment were about $618.6 and $592.4 USD per course respectively, demonstrated patients' demand of pain management. The treatment sensation was regarded as an indicator

  16. A high-speed, eight-wavelength visible light-infrared pyrometer for shock physics experiments

    Science.gov (United States)

    Wang, Rongbo; Li, Shengfu; Zhou, Weijun; Luo, Zhen-Xiong; Meng, Jianhua; Tian, Jianhua; He, Lihua; Cheng, Xianchao

    2017-09-01

    An eight-channel, high speed pyrometer for precise temperature measurement is designed and realized in this work. The addition of longer-wavelength channels sensitive at lower temperatures highly expands the measured temperature range, which covers the temperature of interest in shock physics from 1500K-10000K. The working wavelength range is 400-1700nm from visible light to near-infrared (NIR). Semiconductor detectors of Si and InGaAs are used as photoelectric devices, whose bandwidths are 50MHz and 150MHz respectively. Benefitting from the high responsivity and high speed of detectors, the time resolution of the pyrometer can be smaller than 10ns. By combining the high-transmittance beam-splitters and narrow-bandwidth filters, the peak spectrum transmissivity of each channel can be higher than 60%. The gray-body temperatures of NaI crystal under shock-loading are successfully measured by this pyrometer.

  17. Recent advances in infrared astronomy

    International Nuclear Information System (INIS)

    Robson, E.I.

    1980-01-01

    A background survey is given of developments in infrared astronomy during the last decade. Advantages obtained in using infrared wavelengths to penetrate the Earth's atmosphere and the detectors used for this work are considered. Infrared studies of, among other subjects, the stars, dust clouds, the centre of our galaxy and the 3k cosmic background radiation, are discussed. (UK)

  18. Characterization of silicon microstrip sensors with a pulsed infrared laser system for the CBM experiment at FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Pradeep [Goethe Univ., Frankfurt (Germany); GSI (Germany); Eschke, Juergen [GSI (Germany); FAIR (Germany); Collaboration: CBM-Collaboration

    2014-07-01

    The Silicon Tracking System (STS) for the Compressed Baryonic Matter (CBM) experiment at FAIR will comprise more than 1200 double-sided silicon microstrip sensors. For the quality assurance of the prototype sensors a laser test system has been built up. The aim of the sensor scans with the pulsed infrared laser system is to determine the charge sharing between strips and to measure the uniformity of the sensor response over the whole active area. The laser system measures the sensor response in an automatized procedure at several thousand positions across the sensor with focused infrared laser light (σ∼15 μm, λ=1060 nm). The duration (5 ns) and power (few mW) of the laser pulses are selected such, that the absorption of the laser light in the 300 μm thick silicon sensors produces a number of about 24k electrons, which is similar to the charge created by minimum ionizing particles in these sensors. Results from the characterization of monolithic active pixel sensors, to understand the spot-size of the laser, and laser scans for different sensors are presented.

  19. The cloud monitor by an infrared camera at the Telescope Array experiment

    International Nuclear Information System (INIS)

    Shibata, F.

    2011-01-01

    The mesurement of the extensive air shower using the fluorescence detectors (FDs) is affected by the condition of the atmosphere. In particular, FD aperture is limited by cloudiness. If cloud exists on the light path from extensive air shower to FDs, fluorescence photons will be absorbed drastically. Therefore cloudiness of FD's field of view (FOV) is one of important quality cut condition in FD analysis. In the Telescope Array (TA), an infrared (IR) camera with 320x236 pixels and a filed of view of 25.8 deg. x19.5 deg. has been installed at an observation site for cloud monitoring during FD observations. This IR camera measures temperature of the sky every 30 min during FD observation. IR camera is mounted on steering table, which can be changed in elevation and azimuthal direction. Clouds can be seen at a higher temperature than areas of cloudless sky from these temperature maps. In this paper, we discuss the quality of the cloud monitoring data, the analysis method, and current quality cut condition of cloudiness in FD analysis.

  20. Intracranial Hematoma Detection by Near Infrared Spectroscopy in a Helicopter Emergency Medical Service: Practical Experience.

    Science.gov (United States)

    Schober, Patrick; Bossers, Sebastiaan M; Schwarte, Lothar A

    2017-01-01

    In (helicopter) emergency medical services, (H)EMS, the prehospital detection of intracranial hematomas should improve patient care and the triage to specialized neurosurgical hospitals. Recently, noninvasive detection of intracranial hematomas became possible by applying transcranial near infrared spectroscopy (NIRS). Herein, second-generation devices are currently available, for example, the Infrascanner 2000 (Infrascan), that appear suited also for prehospital (H)EMS applications. Since (H)EMS operations are time-critical, we studied the Infrascanner 2000 as a "first-time-right" monitor in healthy volunteers ( n = 17, hospital employees, no neurologic history). Further, we studied the implementation of the Infrascanner 2000 in a European HEMS organization (Lifeliner 1, Amsterdam, The Netherlands). The principal results of our study were as follows: The screening for intracranial hematomas in healthy volunteers with first-time-right intention resulted in a marked rate of virtual hematomas (false positive results, i.e., 12/17), rendering more time consuming repeat measurements advisable. The results of the implementation of the Infrascanner in HEMS suggest that NIRS-based intracranial hematoma detection is feasible in the HEMS setting. However, some drawbacks exist and their possible solutions are discussed. Future studies will have to demonstrate how NIRS-based intracranial hematoma detection will improve prehospital decision making in (H)EMS and ultimately patient outcome.

  1. Exploring the Cross-Cultural Experiences of College Students with Diverse Backgrounds Performing International Service-Learning in Myanmar

    Science.gov (United States)

    Liu, Ruo-lan; Lee, Hsin-hua

    2011-01-01

    Background: In view of the growing globalization, volunteer service organizations, local universities, colleges, and student groups have begun extending their service programs from Taiwan to other countries. This study employs a self-organized, self-funded group of university students participating in international service-learning as its subject,…

  2. Australian School Practices and the Education Experiences of Students with a Refugee Background: A Review of the Literature

    Science.gov (United States)

    Miller, Emily; Ziaian, Tahereh; Esterman, Adrian

    2018-01-01

    Schools have the potential for significant impact on the lives of Australian students with a refugee background. Many of these young people speak at least one language other than English, have previous histories of interrupted schooling or have experienced trauma during times of displacement and forced migration. Combined with the further…

  3. Development of a multivariate tool to reject background in a WZ diboson search for the CDF experiment

    Energy Technology Data Exchange (ETDEWEB)

    Cremonesi, Matteo [Univ. of of Rome Tor Vergata (Italy)

    2015-08-27

    In the frame of the strong on-going data analysis effort of the CDF collaboration at Fermilab, a method was developed by the candidate to improve the background rejection efficiency in the search for associated pair production of electroweak W, Z bosons. The performaces of the method for vetoing the tt background in a WZ/ZZ → fνq$\\bar{q}$ diboson search are reported. The method was developed in the inclusive 2-jets sample and applied to the “tag-2 jets" region, the subsample defined by the request that the two jets carry beauty flavor. In this region the tt production is one of the largest backgrounds. The tt veto proceeds in two steps: first, a set of pre-selection cuts are applied in a candidate sample where up to two leptons are accepted in addition to a jet pair, and the ZZ component of the signal is thus preserved; next, a Neural Network is trained to indicate the probability that the event be top-pair production. To validate the the method as developed in the inclusive 2-jets sample, it is applied to veto region providing a significant rejection of this important background.

  4. A Case Study of the Experiences of Instructors and Students in a Virtual Learning Environment (VLE) with Different Cultural Backgrounds

    Science.gov (United States)

    Lim, Keol; Kim, Mi Hwa

    2015-01-01

    The use of virtual learning environments (VLEs) has become more common and educators recognized the potential of VLEs as educational environments. The learning community in VLEs can be a mixture of people from all over the world with different cultural backgrounds. However, despite many studies about the use of virtual environments for learning,…

  5. IRST infrared background analysis of bay environments

    CSIR Research Space (South Africa)

    Schwering, PBW

    2008-04-01

    Full Text Available Present-day naval operations take place in coastal environments as well as narrow straits all over the world. Coastal environments around the world are exhibiting a number of threats to naval forces. In particular a large number of asymmetric...

  6. Preliminary test Results for a 25K Sorption Cryocooler Designed for the UCSB Long Duration Balloon Cosmic Microwave Background Radiation Experiment

    Science.gov (United States)

    Wade, L. A.; Levy, A. R.

    1996-01-01

    A continuous operation, vibration-free, long-life 25K sorption cryocooler has been built and is now in final integration and performance testing. This cooler wil be flown on the University of California at Santa Barbara (UCSB) Long Duration Balloon (LDB) Cosmic Microwave Background Radiation Experiment.

  7. The Contribution of Galactic Free-Free Emission to Anistropies in the Cosmic Microwave Background Found by the Saskatoon Experiment

    Science.gov (United States)

    Simonetti, John H.; Dennison, Brian; Topasna, Gregory A.

    1996-02-01

    We made a sensitive, wide-field H alpha image of the north celestial polar region. Using this image, we constrain the contribution of irregularities in interstellar free-free emission to the degree-scale anisotropies in the cosmic microwave background detected in recent observations at Saskatoon by the Princeton group. The analysis of the H alpha image mimics the Saskatoon data analysis: the resulting signal is the strength of irregularities sampled with the Saskatoon beam (i.e., degree-scale) along the 85 deg declination circle. We found no such irregularities that could be attributed to H alpha emission. The implied upper bound on the rms variation in free-free brightness temperature is less than 4.6 mu K at 27.5 GHz. The observed cosmic microwave background anisotropies are much larger. Therefore, the contribution of irregularities in interstellar free-free emission to the observed anisotropies is negligible.

  8. A low-background piston-cylinder type hybrid high pressure cell for muon-spin rotation/relaxation experiments

    OpenAIRE

    Shermadini, Z.; Khasanov, R.; Elender, M.; Simutis, G.; Guguchia, Z.; Kamenev, K. V.; Amato, A.

    2017-01-01

    A low background double-wall piston-cylinder-type pressure cell is developed at the Paul Scherrer Institute. The cell is made from BERLYCO-25 (beryllium copper) and MP35N nonmagnetic alloys with the design and dimensions which are specifically adapted to muon-spin rotation/relaxation (muSR) measurements. The mechanical design and performance of the pressure cell are evaluated using finite-element analysis (FEA). By including the measured stress-strain characteristics of the material into the ...

  9. Modelling of atmospheric mid-infrared radiative transfer: the AMIL2DA algorithm intercomparison experiment

    International Nuclear Information System (INIS)

    Clarmann, T. von; Hoepfner, M.; Funke, B.; Lopez-Puertas, M.; Dudhia, A.; Jay, V.; Schreier, F.; Ridolfi, M.; Ceccherini, S.; Kerridge, B.J.; Reburn, J.; Siddans, R.

    2003-01-01

    When retrieving atmospheric parameters from radiance spectra, the forward modelling of radiative transfer through the Earth's atmosphere plays a key role, since inappropriate modelling directly maps on to the retrieved state parameters. In the context of pre-launch activities of the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) experiment, which is a high resolution limb emission sounder for measurement of atmospheric composition and temperature, five scientific groups intercompared their forward models within the framework of the Advanced MIPAS Level 2 Data Analysis (AMIL2DA) project. These forward models have been developed, or, in certain respects, adapted in order to be used as part of the groups' MIPAS data processing. The following functionalities have been assessed: the calculation of line strengths including non-local thermodynamic equilibrium, the evaluation of the spectral line shape, application of chi-factors and semi-empirical continua, the interpolation of pre-tabulated absorption cross sections in pressure and temperature, line coupling, atmospheric ray tracing, the integration of the radiative transfer equation through an inhomogeneous atmosphere, the convolution of monochromatic spectra with an instrument line shape function, and the integration of the incoming radiances over the instrument field of view

  10. Dangerous gas detection based on infrared video

    Science.gov (United States)

    Ding, Kang; Hong, Hanyu; Huang, Likun

    2018-03-01

    As the gas leak infrared imaging detection technology has significant advantages of high efficiency and remote imaging detection, in order to enhance the detail perception of observers and equivalently improve the detection limit, we propose a new type of gas leak infrared image detection method, which combines background difference methods and multi-frame interval difference method. Compared to the traditional frame methods, the multi-frame interval difference method we proposed can extract a more complete target image. By fusing the background difference image and the multi-frame interval difference image, we can accumulate the information of infrared target image of the gas leak in many aspect. The experiment demonstrate that the completeness of the gas leakage trace information is enhanced significantly, and the real-time detection effect can be achieved.

  11. A low-background piston-cylinder-type hybrid high pressure cell for muon-spin rotation/relaxation experiments

    Science.gov (United States)

    Shermadini, Z.; Khasanov, R.; Elender, M.; Simutis, G.; Guguchia, Z.; Kamenev, K. V.; Amato, A.

    2017-10-01

    A low background double-wall piston-cylinder-type pressure cell is developed at the Paul Scherrer Institute. The cell is made from BERYLCO-25 (beryllium copper) and MP35N nonmagnetic alloys with the design and dimensions which are specifically adapted to muon-spin rotation/relaxation (μSR) measurements. The mechanical design and performance of the pressure cell are evaluated using finite-element analysis (FEA). By including the measured stress-strain characteristics of the materials into the finite-element model, the cell dimensions are optimized with the aim to reach the highest possible pressure while maintaining the sample space large (6 mm in diameter and 12 mm high). The presented unconventional design of the double-wall piston-cylinder pressure cell with a harder outer MP35N sleeve and a softer inner CuBe cylinder enables pressures of up to 2.6 GPa to be reached at ambient temperature, corresponding to 2.2 GPa at low temperatures without any irreversible damage to the pressure cell. The nature of the muon stopping distribution, mainly in the sample and in the CuBe cylinder, results in a low-background μSR signal.

  12. Background sources at PEP

    International Nuclear Information System (INIS)

    Lynch, H.; Schwitters, R.F.; Toner, W.T.

    1988-01-01

    Important sources of background for PEP experiments are studied. Background particles originate from high-energy electrons and positrons which have been lost from stable orbits, γ-rays emitted by the primary beams through bremsstrahlung in the residual gas, and synchrotron radiation x-rays. The effect of these processes on the beam lifetime are calculated and estimates of background rates at the interaction region are given. Recommendations for the PEP design, aimed at minimizing background are presented. 7 figs., 4 tabs

  13. The SIOP Model: Transforming the Experiences of College Professors. Part I. Lesson Planning, Building Background, and Comprehensible Input

    Science.gov (United States)

    Salcedo, Diana M.

    2010-01-01

    This article, the first of two, presents the introduction, context, and analysis of professor experiences in an on-going research project for implementing a new educational model in a bilingual teacher's college in Bogotá, Colombia. The model, the sheltered instruction observation protocol (SIOP) promotes eight components for a bilingual education…

  14. The Impact of Cultural Background and Cross-Cultural Experience on Impressions of American and Korean Male Speakers.

    Science.gov (United States)

    Peng, Ying; And Others

    1993-01-01

    Studies whether people from different cultures form different trait impressions based on identical vocal qualities, and whether cross-cultural experience influences trait impressions. Results for 48 Korean undergraduates in Korea and 32 U.S. undergraduates and 32 Korean graduate students in Boston (Massachusetts) highlight theories of ecological…

  15. Cardiotocography interpretation skills and the association with size of maternity unit, years of obstetric work experience and healthcare professional background

    DEFF Research Database (Denmark)

    Thellesen, Line; Sorensen, Jette Led; Hedegaard, Morten

    2017-01-01

    less than 15 years of obstetric work experience. This might indicate a challenge in maintaining CTG skills in small units and among experienced staff but could also reflect different levels of motivation, test familiarity and learning culture. Whether the findings are transferable to the clinical...... setting was not examined. This article is protected by copyright. All rights reserved....

  16. Experiment-specific cosmic microwave background calculations made easier - Approximation formula for smoothed delta T/T windows

    Science.gov (United States)

    Gorski, Krzysztof M.

    1993-01-01

    Simple and easy to implement elementary function approximations are introduced to the spectral window functions needed in calculations of model predictions of the cosmic microwave backgrond (CMB) anisotropy. These approximations allow the investigator to obtain model delta T/T predictions in terms of single integrals over the power spectrum of cosmological perturbations and to avoid the necessity of performing the additional integrations. The high accuracy of these approximations is demonstrated here for the CDM theory-based calculations of the expected delta T/T signal in several experiments searching for the CMB anisotropy.

  17. Background Material

    DEFF Research Database (Denmark)

    Zandersen, Marianne; Hyytiäinen, Kari; Saraiva, Sofia

    This document serves as a background material to the BONUS Pilot Scenario Workshop, which aims to develop harmonised regional storylines of socio-ecological futures in the Baltic Sea region in a collaborative effort together with other BONUS projects and stakeholders.......This document serves as a background material to the BONUS Pilot Scenario Workshop, which aims to develop harmonised regional storylines of socio-ecological futures in the Baltic Sea region in a collaborative effort together with other BONUS projects and stakeholders....

  18. Turkish University Students’ Perceptions of the World Wide Web as a Learning Tool: An Investigation Based on Gender, Socio-Economic Background, and Web Experience

    Directory of Open Access Journals (Sweden)

    Erkan Tekinarslan

    2009-04-01

    Full Text Available The main purpose of the study is to investigate Turkish undergraduate students’ perceptions of the Web as a learning tool and to analyze whether their perceptions differ significantly based on gender, socio-economic background, and Web experience. Data obtained from 722 undergraduate students (331 males and 391 females were used in the analyses. The findings indicated significant differences based on gender, socio-economic background, and Web experience. The students from higher socio-economic backgrounds indicated significantly higher attitude scores on the self-efficacy subscale of the Web attitude scale. Similarly, the male students indicated significantly higher scores on the self-efficacy subscale than the females. Also, the students with higher Web experience in terms of usage frequency indicated higher scores on all subscales (i.e., self-efficacy, affective, usefulness, Web-based learning. Moreover, the two-way ANOVA results indicated that the student’s PC ownership has significant main effects on their Web attitudes and on the usefulness, self-efficacy, and affective subscales.

  19. Own and parental war experience as a risk factor for mental health problems among adolescents with an immigrant background: results from a cross sectional study in Oslo, Norway

    Science.gov (United States)

    2006-01-01

    Background An increasing proportion of immigrants to Western countries in the past decade are from war affected countries. The aim of this study was to estimate the prevalence of war experience among adolescents and their parents and to investigate possible differences in internalizing and externalizing mental health problems between adolescents exposed and unexposed to own and parental war experience. Method The study is based on a cross-sectional population-based survey of all 10th grade pupils in Oslo for two consecutive years. A total of 1,758 aadolescents were included, all with both parents born outside of Norway. Internalizing and externalizing mental health problems were measured by Hopkins Symptom Checklist-10 and subscales of the Strengths and Difficulties Questionnaire, respectively. Own and parental war experience is based on adolescent self-report. Results The proportion of adolescents with own war experience was 14% with the highest prevalence in immigrants from Eastern Europe and Sub-Saharan Africa. The proportion of parental war experience was 33% with Sub-Saharan Africa being highest. Adolescents reporting own war experience had higher scores for both internalizing and externalizing mental health problems compared to immigrants without war experience, but only externalizing problems reached statistically significant differences. For parental war experience there was a statistically significant relationship between parental war experience and internalizing mental health problems. The association remained significant after adjustment for parental educational level and adolescents' own war experience. Conclusion War exposure is highly prevalent among immigrants living in Oslo, Norway, both among adolescents themselves and their parents. Among immigrants to Norway, parental war experience appears to be stronger associated with mental health problems than adolescents own exposure to war experience. PMID:17081315

  20. Physiological demands of a swimming-based video game: Influence of gender, swimming background, and exergame experience.

    Science.gov (United States)

    Soltani, Pooya; Figueiredo, Pedro; Ribeiro, João; Fernandes, Ricardo J; Vilas-Boas, João Paulo

    2017-07-12

    Active video games (exergames) may provide short-term increase in energy expenditure. We explored the effects of gender and prior experience on aerobic and anaerobic energy systems contributions, and the activity profiles of 40 participants playing with a swimming exergame. We recorded oxygen consumption and assessed blood lactate after each swimming technique. We also filmed participants' gameplays, divided them into different phases and tagged them as active or inactive. Anaerobic pathway accounted for 8.9 ± 5.6% of total energy expenditure and although experienced players were less active compared to novice counterparts (η² increase in physiological measures might happen in the beginning of gameplay because of unfamiliarity with the game mechanics. Despite low levels of activity compared to real sport, both aerobic and anaerobic energy systems should be considered in the evaluation of exergames. Game mechanics (involving the whole body) and strategies to minimize pragmatic play might be used for effective and meaningful game experience.

  1. Fast neutron spectrometry by bolometers lithium target for the reduction of background experiences of direct detection of dark matter

    International Nuclear Information System (INIS)

    Gironnet, J.

    2010-01-01

    Fast neutron spectrometry is a common interest for both direct dark matter detection and for nuclear research centres. Fast neutrons are usually detected indirectly. Neutrons are first slowed down by moderating materials for being detected in low energy range. Nevertheless, these detection techniques are and are limited in energy resolution. A new kind of fast neutron spectroscopy has been developed at the Institut d'Astrophysique Spatiale (IAS) in the aim of having a better knowledge of neutron backgrounds by the association of the bolometric technique with neutron sensitive crystals containing Li. Lithium-6 is indeed an element which has one the highest cross section for neutron capture with the 6 Li(n,α) 3 H reaction. This reaction releases 4,78 MeV tagging energetically each neutron capture. In particular for fast neutrons, the total energy measured by the bolometer would be the sum of this energy reaction and of the incoming fast neutron energy. To validate this principle, a spectrometer for fast neutrons, compact and semi-transportable, was built in IAS. This cryogenic detector, operated at 300 - 400 mK, consists of a 0.5 g LiF 95% 6 Li enriched crystal read out by a NTD-Ge sensor. This PhD thesis was on the study of the spectrometer characteristics, from the first measurements at IAS, to the measurements in the nuclear research centre of the Paul Scherrer Institute (PSI) until the final calibration with the Amande instrument of the Institut de Radioprotection et de Surete Nucleaire (IRSN). (author)

  2. Liquid argon as active shielding and coolant for bare germanium detectors. A novel background suppression method for the GERDA 0νββ experiment

    International Nuclear Information System (INIS)

    Peiffer, J.P.

    2007-01-01

    Two of the most important open questions in particle physics are whether neutrinos are their own anti-particles (Majorana particles) as required by most extensions of the StandardModel and the absolute values of the neutrino masses. The neutrinoless double beta (0νββ) decay, which can be investigated using 76 Ge (a double beta isotope), is the most sensitive probe for these properties. There is a claim for an evidence for the 0νββ decay in the Heidelberg-Moscow (HdM) 76 Ge experiment by a part of the HdM collaboration. The new 76 Ge experiment Gerda aims to check this claim within one year with 15 kg.y of statistics in Phase I at a background level of ≤10 -2 events/(kg.keV.y) and to go to higher sensitivity with 100 kg.y of statistics in Phase II at a background level of ≤10 -3 events/(kg.keV.y). In Gerda bare germanium semiconductor detectors (enriched in 76 Ge) will be operated in liquid argon (LAr). LAr serves as cryogenic coolant and as high purity shielding against external background. To reach the background level for Phase II, new methods are required to suppress the cosmogenic background of the diodes. The background from cosmogenically produced 60 Co is expected to be ∝2.5.10 -3 events/(kg.keV.y). LAr scintillates in UV (λ=128 nm) and a novel concept is to use this scintillation light as anti-coincidence signal for background suppression. In this work the efficiency of such a LAr scintillation veto was investigated for the first time. In a setup with 19 kg active LAr mass a suppression of a factor 3 has been achieved for 60 Co and a factor 17 for 232 Th around Q ββ = 2039 keV. This suppression will further increase for a one ton active volume (factor O(100) for 232 Th and 60 Co). LAr scintillation can also be used as a powerful tool for background diagnostics. For this purpose a new, very stable and robust wavelength shifter/reflector combination for the light detection has been developed, leading to a photo electron (pe) yield of as much as

  3. Liquid argon as active shielding and coolant for bare germanium detectors. A novel background suppression method for the GERDA 0{nu}{beta}{beta} experiment

    Energy Technology Data Exchange (ETDEWEB)

    Peiffer, J.P.

    2007-07-25

    Two of the most important open questions in particle physics are whether neutrinos are their own anti-particles (Majorana particles) as required by most extensions of the StandardModel and the absolute values of the neutrino masses. The neutrinoless double beta (0{nu}{beta}{beta}) decay, which can be investigated using {sup 76}Ge (a double beta isotope), is the most sensitive probe for these properties. There is a claim for an evidence for the 0{nu}{beta}{beta} decay in the Heidelberg-Moscow (HdM) {sup 76}Ge experiment by a part of the HdM collaboration. The new {sup 76}Ge experiment Gerda aims to check this claim within one year with 15 kg.y of statistics in Phase I at a background level of {<=}10{sup -2} events/(kg.keV.y) and to go to higher sensitivity with 100 kg.y of statistics in Phase II at a background level of {<=}10{sup -3} events/(kg.keV.y). In Gerda bare germanium semiconductor detectors (enriched in {sup 76}Ge) will be operated in liquid argon (LAr). LAr serves as cryogenic coolant and as high purity shielding against external background. To reach the background level for Phase II, new methods are required to suppress the cosmogenic background of the diodes. The background from cosmogenically produced {sup 60}Co is expected to be {proportional_to}2.5.10{sup -3} events/(kg.keV.y). LAr scintillates in UV ({lambda}=128 nm) and a novel concept is to use this scintillation light as anti-coincidence signal for background suppression. In this work the efficiency of such a LAr scintillation veto was investigated for the first time. In a setup with 19 kg active LAr mass a suppression of a factor 3 has been achieved for {sup 60}Co and a factor 17 for {sup 232}Th around Q{sub {beta}}{sub {beta}} = 2039 keV. This suppression will further increase for a one ton active volume (factor O(100) for {sup 232}Th and {sup 60}Co). LAr scintillation can also be used as a powerful tool for background diagnostics. For this purpose a new, very stable and robust wavelength

  4. Exposure to space radiation of high-performance infrared multilayer filters and materials technology experiment (A0056)

    Science.gov (United States)

    Hawkins, Gary J.; Seeley, John S.; Hunneman, Roger

    1992-01-01

    Infrared optical multilayer filters and materials were exposed to the space environment of low Earth orbit on LDEF. The effects are summarized of that environment on the physical and optical properties of the filters and materials flown.

  5. The SCUBA-2 Cosmology Legacy Survey: the EGS deep field - I. Deep number counts and the redshift distribution of the recovered cosmic infrared background at 450 and 850 μ m

    Science.gov (United States)

    Zavala, J. A.; Aretxaga, I.; Geach, J. E.; Hughes, D. H.; Birkinshaw, M.; Chapin, E.; Chapman, S.; Chen, Chian-Chou; Clements, D. L.; Dunlop, J. S.; Farrah, D.; Ivison, R. J.; Jenness, T.; Michałowski, M. J.; Robson, E. I.; Scott, Douglas; Simpson, J.; Spaans, M.; van der Werf, P.

    2017-01-01

    We present deep observations at 450 and 850 μm in the Extended Groth Strip field taken with the SCUBA-2 camera mounted on the James Clerk Maxwell Telescope as part of the deep SCUBA-2 Cosmology Legacy Survey (S2CLS), achieving a central instrumental depth of σ450 = 1.2 mJy beam-1 and σ850 = 0.2 mJy beam-1. We detect 57 sources at 450 μm and 90 at 850 μm with signal-to-noise ratio >3.5 over ˜70 arcmin2. From these detections, we derive the number counts at flux densities S450 > 4.0 mJy and S850 > 0.9 mJy, which represent the deepest number counts at these wavelengths derived using directly extracted sources from only blank-field observations with a single-dish telescope. Our measurements smoothly connect the gap between previous shallower blank-field single-dish observations and deep interferometric ALMA results. We estimate the contribution of our SCUBA-2 detected galaxies to the cosmic infrared background (CIB), as well as the contribution of 24 μm-selected galaxies through a stacking technique, which add a total of 0.26 ± 0.03 and 0.07 ± 0.01 MJy sr-1, at 450 and 850 μm, respectively. These surface brightnesses correspond to 60 ± 20 and 50 ± 20 per cent of the total CIB measurements, where the errors are dominated by those of the total CIB. Using the photometric redshifts of the 24 μm-selected sample and the redshift distributions of the submillimetre galaxies, we find that the redshift distribution of the recovered CIB is different at each wavelength, with a peak at z ˜ 1 for 450 μm and at z ˜ 2 for 850 μm, consistent with previous observations and theoretical models.

  6. Experiences with nutrition-related information during antenatal care of pregnant women of different ethnic backgrounds residing in the area of Oslo, Norway.

    Science.gov (United States)

    Garnweidner, Lisa M; Sverre Pettersen, Kjell; Mosdøl, Annhild

    2013-12-01

    to explore experiences with nutrition-related information during routine antenatal care among women of different ethnical backgrounds. individual interviews with seventeen participants were conducted twice during pregnancy. Data collection and analysis were inspired by an interpretative phenomenological approach. participants were purposively recruited at eight Mother and Child Health Centres in the area of Oslo, Norway, where they received antenatal care. participants had either immigrant backgrounds from African and Asian countries (n=12) or were ethnic Norwegian (n=5). Participants were pregnant with their first child and had a pre-pregnancy Body Mass Index above 25 kg/m(2). participants experienced that they were provided with little nutrition-related information in antenatal care. The information was perceived as presented in very general terms and focused on food safety. Weight management and the long-term prevention of diet-related chronic diseases had hardly been discussed. Participants with immigrant backgrounds appeared to be confused about information given by the midwife which was incongruent with their original food culture. The participants were actively seeking for nutrition-related information and had to navigate between various sources of information. the midwife is considered a trustworthy source of nutrition-related information. Therefore, antenatal care may have considerable potential to promote a healthy diet to pregnant women. Findings suggest that nutrition communication in antenatal care should be more tailored towards women's dietary habits and cultural background, nutritional knowledge as well as level of nutrition literacy. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Background radiation

    International Nuclear Information System (INIS)

    Arnott, D.

    1985-01-01

    The effects of background radiation, whether natural or caused by man's activities, are discussed. The known biological effects of radiation in causing cancers or genetic mutations are explained. The statement that there is a threshold below which there is no risk is examined critically. (U.K.)

  8. How people from Chinese backgrounds make sense of and respond to the experiences of mental distress: Thematic analysis.

    Science.gov (United States)

    Yeung, E Y W; Irvine, F; Ng, S M; Tsang, K M S

    2017-10-01

    Many Chinese people do not contact mental health services when they first develop mental health problems. It is therefore important to find out reasons for low uptake of services so that strategies can be identified to promote early intervention. WHAT IS ALREADY KNOWN ABOUT THE TOPIC?: Most Chinese people only come into contact with mental health services during crisis situations. Language difference, lack of knowledge of mainstream services and stigma attached to mental health problems are barriers to access and utilize mental health services. WHAT THE STUDY ADDS TO THE INTERNATIONAL EVIDENCE?: Chinese people apply both Western medication and traditional healing to manage distress caused by mental health problems. Because of the extreme stigma associated with mental health problems, Chinese people are reluctant to accept support from their own cultural groups outside their family. Family plays a major role in caring for relatives with mental health problems. Families are prepared to travel across the world in search of folk healing if not available in Western societies. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: It is important to recognize the different approaches to understanding and managing mental health problems among Chinese people, otherwise they will be dissuaded from engaging with mental health services if their beliefs are disregarded and invalidated. Services that involve Chinese speaking mental health workers can address the issue of language differences and sensitive mental health issues within the Chinese community. Introduction Late presentation and low utilization of mental health services are common among Chinese populations. An understanding of their journey towards mental health care helps to identify timely and appropriate intervention. Aim We aimed to examine how Chinese populations make sense of the experiences of mental distress, and how this understanding influences their pathways to mental health care. Method We undertook in-depth interviews

  9. The Significance of an Excess in a Counting Experiment: Assessing the Impact of Systematic Uncertainties and the Case with a Gaussian Background

    Science.gov (United States)

    Vianello, Giacomo

    2018-05-01

    Several experiments in high-energy physics and astrophysics can be treated as on/off measurements, where an observation potentially containing a new source or effect (“on” measurement) is contrasted with a background-only observation free of the effect (“off” measurement). In counting experiments, the significance of the new source or effect can be estimated with a widely used formula from Li & Ma, which assumes that both measurements are Poisson random variables. In this paper we study three other cases: (i) the ideal case where the background measurement has no uncertainty, which can be used to study the maximum sensitivity that an instrument can achieve, (ii) the case where the background estimate b in the off measurement has an additional systematic uncertainty, and (iii) the case where b is a Gaussian random variable instead of a Poisson random variable. The latter case applies when b comes from a model fitted on archival or ancillary data, or from the interpolation of a function fitted on data surrounding the candidate new source/effect. Practitioners typically use a formula that is only valid when b is large and when its uncertainty is very small, while we derive a general formula that can be applied in all regimes. We also develop simple methods that can be used to assess how much an estimate of significance is sensitive to systematic uncertainties on the efficiency or on the background. Examples of applications include the detection of short gamma-ray bursts and of new X-ray or γ-ray sources. All the techniques presented in this paper are made available in a Python code that is ready to use.

  10. Understanding internal backgrounds in NaI(Tl) crystals toward a 200 kg array for the KIMS-NaI experiment

    Energy Technology Data Exchange (ETDEWEB)

    Adhikari, P.; Adhikari, G.; Oh, S.Y. [Sejong University, Department of Physics, Seoul (Korea, Republic of); Choi, S.; Joo, H.W.; Kim, K.W.; Kim, S.K. [Seoul National University, Department of Physics and Astronomy, Seoul (Korea, Republic of); Ha, C.; Jeon, E.J.; Kang, W.G.; Kim, H.O.; Kim, N.Y.; Lee, H.S.; Lee, J.H.; Lee, M.H.; Leonard, D.S.; Li, J.; Olsen, S.L.; Park, H.K.; Park, K.S.; So, J.H.; Yoon, Y.S. [Institute for Basic Science, Center for Underground Physics, Daejeon (Korea, Republic of); Hahn, I.S. [Ewha Womans University, Department of Science Education, Seoul (Korea, Republic of); Kim, H.J. [Kyungpook National University, Department of Physics, Daegu (Korea, Republic of); Kim, Y.D. [Sejong University, Department of Physics, Seoul (Korea, Republic of); Institute for Basic Science, Center for Underground Physics, Daejeon (Korea, Republic of); Kim, Y.H. [Institute for Basic Science, Center for Underground Physics, Daejeon (Korea, Republic of); Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of); Park, H.S. [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

    2016-04-15

    The Korea Invisible Mass Search (KIMS) collaboration has developed low-background NaI(Tl) crystals that are suitable for the direct detection of WIMP dark matter. Building on experience accumulated during the KIMS-CsI programs, the KIMS-NaI experiment will consist of a 200 kg NaI(Tl) crystal array surrounded by layers of shielding structures and will be operated at the Yangyang underground laboratory. The goal is to provide an unambiguous test of the DAMA/LIBRA annual modulation signature. Measurements of six prototype crystals show progress in the reduction of internal contamination from radioisotopes. Based on our understanding of these measurements, we expect to achieve a background level in the final detector configuration that is less than 1 count/day/keV/kg for recoil energies around 2 keV. The annual modulation sensitivity for the KIMS-NaI experiment shows that an unambiguous 7σ test of the DAMA/LIBRA signature would be possible with a 600 kg year exposure with this system. (orig.)

  11. Infrared and Raman spectroscopy: principles and spectral interpretation

    National Research Council Canada - National Science Library

    Larkin, Peter

    2011-01-01

    "Infrared and Raman Spectroscopy: Principles and Spectral Interpretation explains the background, core principles and tests the readers understanding of the important techniques of Infrared and Raman Spectroscopy...

  12. Illness Perception and Clinical Treatment Experiences in Patients with M. Maroteaux-Lamy (Mucopolysaccharidosis Type VI) and a Turkish Migration Background in Germany

    Science.gov (United States)

    Dilger, Hansjörg; Leissner, Linn; Bosanska, Lenka; Lampe, Christina; Plöckinger, Ursula

    2013-01-01

    Introduction Mucopolysaccharidosis VI (MPS VI) is an inherited lysosomal storage disease caused by a mutation of the gene for arylsulfatase B (ASB). Of the thirty-one patients registered in Germany, almost fifty percent have a Turkish migration background. MPS VI is treated by enzyme replacement therapy (ERT), which is time-consuming and expensive. Methods This interdisciplinary study explored the illness perceptions and clinical treatment experiences among ten MPS VI patients with a Turkish migration background in two centers for metabolic diseases (Berlin and Mainz, Germany). The clinical treatment situation was observed and semi-structured interviews were conducted with patients and health care personnel, in addition to participatory observation in four patients' everyday environments in Berlin. The data from the interviews, patient records, and personal field notes were encoded, cross-related, and analyzed. Results Patients' acknowledgement of the disease and coping strategies are influenced predominantly by the perception of their individual health status and the handling of the disease within their family. Patients' willingness to cooperate with treatment strategies is further modified by their knowledge of the disease and the relationships with their health care providers. In this analysis, cultural factors turned out to be marginally relevant. Conclusion As with other chronic and debilitating diseases, effective treatment strategies have to reach beyond delivering medication. Health care providers need to strengthen the support for patients with a migration background. In this regard, they should respect the patients' cultural and social background and their personal perception of the disease and the therapy. Yet structural and social aspects (clinical setting, family and educational background) may be more crucial here than “cultural barriers.” PMID:23826140

  13. Dental Caries Experience and Utilization of Oral Health Services Among Tibetan Refugee-Background Children in Paonta Sahib, Himachal Pradesh, India.

    Science.gov (United States)

    Bhatt, Sumeet; Gaur, Ambika

    2018-06-04

    The study was done to describe the dental caries experience and dental care utilization among Tibetan refugee-background children in Paonta Sahib, India. The study was conducted on 254 school children in a Tibetan settlement in Paonta Sahib. Examination was done as per World Health Organization Oral Health Assessment criteria (2013). Data on dental services utilization was obtained from the parents of children using a structured questionnaire. Oral examination of 254 school children aged 6-18 years revealed an overall dental caries prevalence of 79.5%. The dental caries experience was greater in the mixed dentition (84%) than secondary dentition (77.3%). The mean DMFT was associated with sex and dental visiting patterns. About 60% children had never visited a dentist before. The main reason for dental visit was tooth removal (43%). The prevalence of dental caries among Tibetan refugee-background school children was high and utilization of dental care was low. A comprehensive oral health program focusing on preventive care and oral health education is recommended.

  14. Inline monitoring of adsorption of Butane Isomers with near infrared spectroscopy: Drift Correction in time based experiments

    NARCIS (Netherlands)

    Ferreira, A.; Boelens, H.F.M.; Westerhuis, J.A.

    2005-01-01

    Near-infrared (NIR) spectroscopy is used to monitor online a large variety of processes. Hydrocarbons with their strong NIR spectral signature are good candidate analytes. For this work, the sorption data are measured in a manometric setup coupled with online NIR spectroscopy, to monitor the bulk

  15. Applications of Group Theory: Infrared and Raman Spectra of the Isomers of 1,2-Dichloroethylene: A Physical Experiment

    Science.gov (United States)

    Craig, Norman C.; Lacuesta, Nanette N.

    2004-01-01

    A study of the vibrational spectroscopy of the cis and trans isomers of 1,2-dichloroethylene provides an excellent opportunity to learn the applications group theory in laboratories. The necessity of using infrared (IR) spectroscopy and Raman spectroscopy in making full vibrational assignments is illustrated.

  16. Optimal background matching camouflage.

    Science.gov (United States)

    Michalis, Constantine; Scott-Samuel, Nicholas E; Gibson, David P; Cuthill, Innes C

    2017-07-12

    Background matching is the most familiar and widespread camouflage strategy: avoiding detection by having a similar colour and pattern to the background. Optimizing background matching is straightforward in a homogeneous environment, or when the habitat has very distinct sub-types and there is divergent selection leading to polymorphism. However, most backgrounds have continuous variation in colour and texture, so what is the best solution? Not all samples of the background are likely to be equally inconspicuous, and laboratory experiments on birds and humans support this view. Theory suggests that the most probable background sample (in the statistical sense), at the size of the prey, would, on average, be the most cryptic. We present an analysis, based on realistic assumptions about low-level vision, that estimates the distribution of background colours and visual textures, and predicts the best camouflage. We present data from a field experiment that tests and supports our predictions, using artificial moth-like targets under bird predation. Additionally, we present analogous data for humans, under tightly controlled viewing conditions, searching for targets on a computer screen. These data show that, in the absence of predator learning, the best single camouflage pattern for heterogeneous backgrounds is the most probable sample. © 2017 The Authors.

  17. Study of the neutron background noise generated by muons in the Edelweiss-2 experiment; Etude du bruit de fond neutron induit par les muons dans l'experience EDELWEISS-2

    Energy Technology Data Exchange (ETDEWEB)

    Chabert, L

    2004-07-01

    This thesis contributes to the Edelweiss experiment whose aim is to detect interactions between neutralinos and target nuclei. Bolometers used in Edelweiss combine the detection of phonons with the detection of electric charges generated by the energy deposition. This double detection enables us to discard background signals due to electronic interactions and soon detection sensitivity of the experiment will be limited by the neutron background noise due to residual cosmic muons. This work is dedicated to a detailed study of muon inelastic interactions and the consequent production of neutrons. Simulations show that the expected neutron flux is so high that the direct detection of muons is required in order to link it to the neutron signal issued by the bolometer. Results from simulations show that plastic scintillators might be the main components of the muon detector.

  18. Background Music and Background Feelings

    DEFF Research Database (Denmark)

    Have, Iben

    2008-01-01

    With a focus on underscore music in film and television this report discusses the relations between music and emotions. The report will present and discuss an interdisciplinary theoretical framework connecting the experience of musical structures with emotional structures. Subsequently it discuss...... how music in the attachment to the audiovisual context contributes to the generation of different kinds of emotional experiences. The Danish television documentary Ballets droning (“The Queen of the Ball”) portraying the leader of the Danish right wing party The Danish Peoples’ Party...

  19. Solar neutrinos as a signal and background in direct-detection experiments searching for sub-GeV dark matter with electron recoils

    Science.gov (United States)

    Essig, Rouven; Sholapurkar, Mukul; Yu, Tien-Tien

    2018-05-01

    Direct-detection experiments sensitive to low-energy electron recoils from sub-GeV dark matter interactions will also be sensitive to solar neutrinos via coherent neutrino-nucleus scattering (CNS), since the recoiling nucleus can produce a small ionization signal. Solar neutrinos constitute both an interesting signal in their own right and a potential background to a dark matter search that cannot be controlled or reduced by improved shielding, material purification and handling, or improved detector design. We explore these two possibilities in detail for semiconductor (silicon and germanium) and xenon targets, considering several possibilities for the unmeasured ionization efficiency at low energies. For dark-matter-electron-scattering searches, neutrinos start being an important background for exposures larger than ˜1 - 10 kg -years in silicon and germanium, and for exposures larger than ˜0.1 - 1 kg -year in xenon. For the absorption of bosonic dark matter (dark photons and axion-like particles) by electrons, neutrinos are most relevant for masses below ˜1 keV and again slightly more important in xenon. Treating the neutrinos as a signal, we find that the CNS of 8B neutrinos can be observed with ˜2 σ significance with exposures of ˜2 , 7, and 20 kg-years in xenon, germanium, and silicon, respectively, assuming there are no other backgrounds. We give an example for how this would constrain nonstandard neutrino interactions. Neutrino components at lower energy can only be detected if the ionization efficiency is sufficiently large. In this case, observing pep neutrinos via CNS requires exposures ≳10 - 100 kg -years in silicon or germanium (˜1000 kg -years in xenon), and observing CNO neutrinos would require an order of magnitude more exposure. Only silicon could potentially detect 7Be neutrinos. These measurements would allow for a direct measurement of the electron-neutrino survival probability over a wide energy range.

  20. Measured and Modeled Downwelling Far-Infrared Radiances in Very Dry Environments and Calibration Requirements for Future Experiments

    Science.gov (United States)

    Mast, J. C.; Mlynczak, M. G.; Cageao, R.; Kratz, D. P.; Latvakoski, H.; Johnson, D. G.; Mlawer, E. J.; Turner, D. D.

    2016-12-01

    Downwelling radiances measured by the Far-Infrared Spectroscopy of the Troposphere (FIRST) instrument in an environment with integrated precipitable water as low as 0.03 cm are compared with calculated spectra in the far-infrared and mid-infrared. In its current ground-based configuration FIRST was deployed to 5.38 km on Cerro Toco, a mountain in the Atacama Desert of Chile, from August to October 2009. There FIRST took part in the Radiative Heating in Unexplored Bands Campaign Part 2. Water vapor and temperature profiles from an optimal-estimation-based physical retrieval algorithm (using simultaneous radiosonde and multichannel 183 GHz microwave radiometer measurements) are input to the AER Line-by-Line Radiative Transfer Model (LBLRTM) to compute radiances for comparison with FIRST. The AER v3.4 line parameter database is used. The low water vapor amounts and relatively cold atmosphere result in extremely small far-IR radiances (1.5 mW/m2/sr/cm-1) with corresponding brightness temperatures of 120 K. The residual LBLRTM minus FIRST is calculated to assess agreement between the measured and modeled spectra. Uncertainties in both the measured and modeled radiances are accounted for in the comparison. A goal of the deployment and subsequent analysis is the assessment of water vapor spectroscopy in the far-infrared and mid-infrared. While agreement is found between measured and modeled radiances within the combined uncertainties across all spectra, uncertainties in the measured water vapor profiles and from the laboratory calibration exceed those associated with water vapor spectroscopy in this very low radiance environment. Consequently, no improvement in water vapor spectroscopy is afforded by these measurements. However, we use these results to place requirements on instrument calibration accuracy and water vapor profile accuracy for future campaigns to similarly dry environments. Instrument calibration uncertainty needs to be at 2% (1-sigma) of measured radiance

  1. Spotlight on equality of employment opportunities: A qualitative study of job seeking experiences of graduating nurses and physiotherapists from black and minority ethnic backgrounds.

    Science.gov (United States)

    Hammond, John; Marshall-Lucette, Sylvie; Davies, Nigel; Ross, Fiona; Harris, Ruth

    2017-09-01

    There is growing attention in the UK and internationally to the representation of black and minority ethnic groups in healthcare education and the workplace. Although the NHS workforce is very diverse, ethnic minorities are unevenly spread across occupations, and considerably underrepresented in senior positions. Previous research has highlighted that this inequality also exists at junior levels with newly qualified nurses from non-White/British ethnic groups being less likely to get a job at graduation than their White/British colleagues. Although there is better national data on the scale of inequalities in the healthcare workforce, there is a gap in our understanding about the experience of job seeking, and the factors that influence disadvantage in nursing and other professions such as physiotherapy. This qualitative study seeks to fill that gap and explores the experience of student nurses (n=12) and physiotherapists (n=6) throughout their education and during the first 6-months post qualification to identify key experiences and milestones relating to successful employment particularly focusing on the perspectives from different ethnic groups. Participants were purposively sampled from one university to ensure diversity in ethnic group, age and gender. Using a phenomenological approach, in-depth semi-structured interviews were conducted at course completion and 6 months later. Two main themes were identified. The 'proactive self' ('It's up to me') theme included perceptions of employment success being due to student proactivity and resilience; qualities valued by employers. The second theme described the need to 'fit in' with organisational culture. Graduates described accommodating strategies where they modified aspects of their identity (clothing, cultural markers) to fit in. At one extreme, rather than fitting in, participants from minority ethnic backgrounds avoided applying to certain hospitals due to perceptions of discriminatory cultures, 'I wouldn

  2. Transfer of infrared thermography predictive maintenance technologies to Soviet-designed nuclear power plants: experience at Chernobyl

    Science.gov (United States)

    Pugh, Ray; Huff, Roy

    1999-03-01

    The importance of infrared (IR) technology and analysis in today's world of predictive maintenance and reliability- centered maintenance cannot be understated. The use of infrared is especially important in facilities that are required to maintain a high degree of equipment reliability because of plant or public safety concerns. As with all maintenance tools, particularly those used in predictive maintenance approaches, training plays a key role in their effectiveness and the benefit gained from their use. This paper details an effort to transfer IR technology to Soviet- designed nuclear power plants in Russia, Ukraine, and Lithuania. Delivery of this technology and post-delivery training activities have been completed recently at the Chornobyl nuclear power plant in Ukraine. Many interesting challenges were encountered during this effort. Hardware procurement and delivery of IR technology to a sensitive country were complicated by United States regulations. Freight and shipping infrastructure and host-country customs policies complicated hardware transport. Training activities were complicated by special hardware, software and training material translation needs, limited communication opportunities, and site logistical concerns. These challenges and others encountered while supplying the Chornobyl plant with state-of-the-art IR technology are described in this paper.

  3. Feasibility study of a microwave or far-infrared scattering experiment to measure small scale turbulence and anomalous transport in J.E.T

    International Nuclear Information System (INIS)

    Koechlin, F.; Olivain, J.; Gresillon, D.; Truc, A.

    1981-03-01

    In the first part, we make a rapid review of what can be expected as low frequency turbulence in J.E.T. This is to define the parameters of the density fluctuations which can be expected. A method to deduce the anomalous transport is described. In the second part, the physical problems of measuring these parameters by microwave or far-infrared scattering are outlined. In the third part, a preliminary study of a microwave scattering experiment at lambda approximately 1.3 mm is made. In the fourth part, a F.I.R. laser experiment at 10.6 μm is also proposed to perform the same measurements. In this last case, an estimation of the thermal nature of the plasma emission could be made, in order to eventually extend the diagnostic to the ion temperature measurement

  4. Infrared astronomy

    International Nuclear Information System (INIS)

    Setti, G.; Fazio, G.

    1978-01-01

    This volume contains lectures describing the important achievements in infrared astronomy. The topics included are galactic infrared sources and their role in star formation, the nature of the interstellar medium and galactic structure, the interpretation of infrared, optical and radio observations of extra-galactic sources and their role in the origin and structure of the universe, instrumental techniques and a review of future space observations. (C.F.)

  5. Development of a non destructive evaluation system using infrared images for divertor on nuclear fusion experiment reactor

    International Nuclear Information System (INIS)

    Yokoyama, Kenji; Suzuki, Satoshi; Ezato, Koichiro; Seki, Yohji; Enoeda, Mikio; Akiba, Masato

    2008-01-01

    An infrared thermography NDE facility which is utilized in the acceptance test of ITER divertor components has been developed in JAEA. This NDE facility can inspect the integrity of the bonding interface of the divertor components based on its surface temperature response by means of switching of hot (95 deg C)/cold (5 deg C) water. The advantages of this facility are 1) to have active coolant purging system which enables rapid temperature change and 2) to inspect the surface and the both side walls of three components at a time. We have conduct test operation for the divertor mockups and have found sufficient performance to implement the required acceptance test of the ITER divertor components. (author)

  6. Lead-chalcogenide mid-infrared vertical external cavity surface emitting lasers with improved threshold: Theory and experiment

    Science.gov (United States)

    Fill, Matthias; Debernardi, Pierluigi; Felder, Ferdinand; Zogg, Hans

    2013-11-01

    Mid-infrared Vertical External Cavity Surface Emitting Lasers (VECSEL) based on narrow gap lead-chalcogenide (IV-VI) semiconductors exhibit strongly reduced threshold powers if the active layers are structured laterally for improved optical confinement. This is predicted by 3-d optical calculations; they show that lateral optical confinement is needed to counteract the anti-guiding features of IV-VIs due to their negative temperature dependence of the refractive index. An experimental proof is performed with PbSe quantum well based VECSEL grown on a Si-substrate by molecular beam epitaxy and emitting around 3.3 μm. With proper mesa-etching, the threshold intensity is about 8-times reduced.

  7. Lead-chalcogenide mid-infrared vertical external cavity surface emitting lasers with improved threshold: Theory and experiment

    Energy Technology Data Exchange (ETDEWEB)

    Fill, Matthias [ETH Zurich, Laser Spectroscopy and Sensing Lab, 8093 Zurich (Switzerland); Phocone AG, 8005 Zurich (Switzerland); Debernardi, Pierluigi [IEIIT-CNR, Torino 10129 (Italy); Felder, Ferdinand [Phocone AG, 8005 Zurich (Switzerland); Zogg, Hans [ETH Zurich (Switzerland)

    2013-11-11

    Mid-infrared Vertical External Cavity Surface Emitting Lasers (VECSEL) based on narrow gap lead-chalcogenide (IV-VI) semiconductors exhibit strongly reduced threshold powers if the active layers are structured laterally for improved optical confinement. This is predicted by 3-d optical calculations; they show that lateral optical confinement is needed to counteract the anti-guiding features of IV-VIs due to their negative temperature dependence of the refractive index. An experimental proof is performed with PbSe quantum well based VECSEL grown on a Si-substrate by molecular beam epitaxy and emitting around 3.3 μm. With proper mesa-etching, the threshold intensity is about 8-times reduced.

  8. Infrared Astronomy and Education: Linking Infrared Whole Sky Mapping with Teacher and Student Research

    Science.gov (United States)

    Borders, Kareen; Mendez, Bryan; Thaller, Michelle; Gorjian, Varoujan; Borders, Kyla; Pitman, Peter; Pereira, Vincent; Sepulveda, Babs; Stark, Ron; Knisely, Cindy; Dandrea, Amy; Winglee, Robert; Plecki, Marge; Goebel, Jeri; Condit, Matt; Kelly, Susan

    The Spitzer Space Telescope and the recently launched WISE (Wide Field Infrared Survey Explorer) observe the sky in infrared light. Among the objects WISE will study are asteroids, the coolest and dimmest stars, and the most luminous galaxies. Secondary students can do authentic research using infrared data. For example, students will use WISE data to mea-sure physical properties of asteroids. In order to prepare students and teachers at this level with a high level of rigor and scientific understanding, the WISE and the Spitzer Space Tele-scope Education programs provided an immersive teacher professional development workshop in infrared astronomy.The lessons learned from the Spitzer and WISE teacher and student pro-grams can be applied to other programs engaging them in authentic research experiences using data from space-borne observatories such as Herschel and Planck. Recently, WISE Educator Ambassadors and NASA Explorer School teachers developed and led an infrared astronomy workshop at Arecibo Observatory in PuertoRico. As many common misconceptions involve scale and distance, teachers worked with Moon/Earth scale, solar system scale, and distance and age of objects in the Universe. Teachers built and used basic telescopes, learned about the history of telescopes, explored ground and satellite based telescopes, and explored and worked on models of WISE Telescope. An in-depth explanation of WISE and the Spitzer telescopes gave participants background knowledge for infrared astronomy observations. We taught the electromagnetic spectrum through interactive stations. We will outline specific steps for sec-ondary astronomy professional development, detail student involvement in infrared telescope data analysis, provide data demonstrating the impact of the above professional development on educator understanding and classroom use, and detail future plans for additional secondary professional development and student involvement in infrared astronomy. Funding was

  9. HARLIE 3-D Aerosol Backscatter and Wind Profile Measurements During Recent Field Experiments: Background Noise Reduction with a Fabry-Perot Etalon Filter in the HARLIE System

    Science.gov (United States)

    Lee, Sangwoo; Miller, David O.; Schwemmer, Geary; Wilkerson, Thomas D.; Andrus, Ionio; Egbert, Cameron; Anderson, Mark; Starr, David OC. (Technical Monitor)

    2002-01-01

    Background noise reduction of War signals is one of the most important factors in achieving better signal to noise ratio and precise atmospheric data from Mar measurements. Fahey Perot etalons have been used in several lidar systems as narrow band pass filters in the reduction of scattered sunlight. An slalom with spectral bandwidth, (Delta)v=0.23/cm, free spectral range, FSR=6.7/cm, and diameter, d=24mm was installed in a fiber coupled box which included a 500 pm bandwidth interference Filter. The slalom box couples the telescope and detector with 200 pm core fibers and 21 mm focal length collimators. The angular magnification is M=48. The etalon box was inserted into the Holographic Airborne Rotating Lidar Instrument Experiment (HARLIE) system and tested during the HARGLO-2 intercomparison campaign conducted in November 2001 at Wallops Island, Virginia. This paper presents the preliminary test results of the slalom and a complete analysis will be presented at the conference.

  10. Judges in the Formation of the Nation- State: Professional Experiences, Academic Background and Geographic Circulation of Members of the Supreme Courts of Brazil and the United States

    Directory of Open Access Journals (Sweden)

    Luciano Da Ros

    2010-06-01

    Full Text Available This article compares the career profiles of judges from the highest bodies of the Judiciary in Brazil and the United States of America, examining the biographies of all the ministros of the Supreme Court of Justice (Empire and of the Supreme Federal Tribunal (Republic in Brazil, and of all the justices of the Supreme Court of the United States, appointed until 2008 in both cases. Based on the sociology of political elites perspective, the article examines data concerning academic background, geographic circulation and the different professional experiences — legal, political and linked to the administration of the State’s coercive activity (police or military — lived through by future members of the Supreme Courts of Brazil and the United States so as to identify the types of individuals recommended to join the top bodies of the Judiciary in the two countries. In this sense, different State-building processes are identified on the basis of the examination of Brazilian and US judicial elites, suggesting a more fragmented and diverse trajectory in the case of US justices, and greater homogeneity and centralization in the case of their Brazilian counterparts.

  11. Analysis and research on thermal infrared properties and adaptability of the camouflage net

    Science.gov (United States)

    Cui, Guangzhen; Hu, Jianghua; Jian, Chaochao; Yang, Juntang

    2016-10-01

    As camouflage equipment, camouflage net which covers or obstruct the enemy reconnaissance and attack, have the compatibility such as optics, infrared, radar wave band performance. To improve the adaptive between the camouflage net with background in infrared wavelengths, the heat shield and heat integration requirements on the surface of the camouflage net was analyzed. The condition that satisfied the heat shield was when the average thermal infrared transmittance was less than 25.38% on camouflage screen surface. Studies have shown that camouflage nets and the background field fused together when infrared radiation temperature difference control is within the scope of ± 4K . Experiment on temperature contrast was tested in situ background, thermal camouflage spots and camouflage net with sponge material, the infrared heat maps was recorded in the period of experiment through the thermal imager. Results showed that the thermal inertia of camouflage net was markedly lower than the background and the exposed signs were obvious. It was difficult to reach camouflage thermal infrared fusion requirements by relying on camouflage spot emissivity, but sponge which mix with polymer resin can reduce target significance in the context of mottled and realize the fusion effect.

  12. Berkeley Low Background Facility

    International Nuclear Information System (INIS)

    Thomas, K. J.; Norman, E. B.; Smith, A. R.; Poon, A. W. P.; Chan, Y. D.; Lesko, K. T.

    2015-01-01

    The Berkeley Low Background Facility (BLBF) at Lawrence Berkeley National Laboratory (LBNL) in Berkeley, California provides low background gamma spectroscopy services to a wide array of experiments and projects. The analysis of samples takes place within two unique facilities; locally within a carefully-constructed, low background laboratory on the surface at LBNL and at the Sanford Underground Research Facility (SURF) in Lead, SD. These facilities provide a variety of gamma spectroscopy services to low background experiments primarily in the form of passive material screening for primordial radioisotopes (U, Th, K) or common cosmogenic/anthropogenic products; active screening via neutron activation analysis for U,Th, and K as well as a variety of stable isotopes; and neutron flux/beam characterization measurements through the use of monitors. A general overview of the facilities, services, and sensitivities will be presented. Recent activities and upgrades will also be described including an overview of the recently installed counting system at SURF (recently relocated from Oroville, CA in 2014), the installation of a second underground counting station at SURF in 2015, and future plans. The BLBF is open to any users for counting services or collaboration on a wide variety of experiments and projects

  13. Characterization of silicon micro-strip sensors with a pulsed infra-red laser system for the CBM experiment at FAIR

    International Nuclear Information System (INIS)

    Ghosh, P.

    2015-01-01

    The Compressed Baryonic Matter (CBM) experiment at FAIR is composed of 8 tracking stations consisting of 1292 double sided silicon micro-strip sensors. For the quality assurance of produced prototype sensors a laser test system (LTS) has been developed. The aim of the LTS is to scan sensors with a pulsed infra-red laser driven by step motor to determine the charge sharing in-between strips and to measure qualitative uniformity of the sensor response over the whole active area. The prototype sensors which are tested with the LTS so far have 256 strips with a pitch of 50 μm on each side. They are read-out using a self-triggering prototype read-out electronic ASIC called n-XYTER. The LTS is designed to measure sensor response in an automatized procedure at several thousand positions across the sensor with focused infra-red laser light (spot size ≈ 12 μm , wavelength = 1060 nm). The pulse with duration (≈ 10 ns) and power (≈ 5 mW) of the laser pulses is selected such, that the absorption of the laser light in the 300 μm thick silicon sensors produces a number of about 24000 electrons, which is similar to the charge created by minimum ionizing particles (MIP) in these sensors. Laser scans different prototype sensors is reported

  14. Infrared thermography

    CERN Document Server

    Meola, Carosena

    2012-01-01

    This e-book conveys information about basic IRT theory, infrared detectors, signal digitalization and applications of infrared thermography in many fields such as medicine, foodstuff conservation, fluid-dynamics, architecture, anthropology, condition monitoring, non destructive testing and evaluation of materials and structures.

  15. Experimental Determination of Infrared Extinction Coefficients of Interplanetary Dust Particles

    Science.gov (United States)

    Spann, J. F., Jr.; Abbas, M. M.

    1998-01-01

    This technique is based on irradiating a single isolated charged dust particle suspended in balance by an electric field, and measuring the scattered radiation as a function of angle. The observed scattered intensity profile at a specific wavelength obtained for a dust particle of known composition is compared with Mie theory calculations, and the variable parameters relating to the particle size and complex refractive index are adjusted for a best fit between the two profiles. This leads to a simultaneous determination of the particle radius, the complex refractive index, and the scattering and extinction coefficients. The results of these experiments can be utilized to examine the IRAS and DIRBE (Diffuse Infrared Background Experiment) infrared data sets in order to determine the dust particle physical characteristics and distributions by using infrared models and inversion techniques. This technique may also be employed for investigation of the rotational bursting phenomena whereby large size cosmic and interplanetary particles are believed to fragment into smaller dust particles.

  16. Infrared Sky Surveys

    Science.gov (United States)

    Price, Stephan D.

    2009-02-01

    A retrospective is given on infrared sky surveys from Thomas Edison’s proposal in the late 1870s to IRAS, the first sensitive mid- to far-infrared all-sky survey, and the mid-1990s experiments that filled in the IRAS deficiencies. The emerging technology for space-based surveys is highlighted, as is the prominent role the US Defense Department, particularly the Air Force, played in developing and applying detector and cryogenic sensor advances to early mid-infrared probe-rocket and satellite-based surveys. This technology was transitioned to the infrared astronomical community in relatively short order and was essential to the success of IRAS, COBE and ISO. Mention is made of several of the little known early observational programs that were superseded by more successful efforts.

  17. Overview of the Brooklyn traffic real-time ambient pollutant penetration and environmental dispersion (B-TRAPPED) study: theoretical background and model for design of field experiments.

    Science.gov (United States)

    Hahn, Intaek; Wiener, Russell W; Richmond-Bryant, Jennifer; Brixey, Laurie A; Henkle, Stacy W

    2009-12-01

    The Brooklyn traffic real-time ambient pollutant penetration and environmental dispersion (B-TRAPPED) study was a multidisciplinary field research project that investigated the transport, dispersion, and infiltration processes of traffic emission particulate matter (PM) pollutants in a near-highway urban residential area. The urban PM transport, dispersion, and infiltration processes were described mathematically in a theoretical model that was constructed to develop the experimental objectives of the B-TRAPPED study. In the study, simultaneous and continuous time-series PM concentration and meteorological data collected at multiple outdoor and indoor monitoring locations were used to characterize both temporal and spatial patterns of the PM concentration movements within microscale distances (street canyon; (2) investigating the effects of urban structures such as a tall building or an intersection on the transport and dispersion of PM; (3) studying the influence of meteorological variables on the transport, dispersion, and infiltration processes; (4) characterizing the relationships between the building parameters and the infiltration mechanisms; (5) establishing a cause-and-effect relationship between outdoor-released PM and indoor PM concentrations and identifying the dominant mechanisms involved in the infiltration process; (6) evaluating the effectiveness of a shelter-in-place area for protection against outdoor-released PM pollutants; and (7) understanding the predominant airflow and pollutant dispersion patterns within the neighborhood using wind tunnel and CFD simulations. The 10 papers in this first set of papers presenting the results from the B-TRAPPED study address these objectives. This paper describes the theoretical background and models representing the interrelated processes of transport, dispersion, and infiltration. The theoretical solution for the relationship between the time-dependent indoor PM concentration and the initial PM concentration

  18. Are Schools Promoting Social and Economic Integration of Migrant and Ethnic Minorities? The Experiences of Some Young People of Ecuadorian Background in Spain

    Science.gov (United States)

    Ron-Balsera, Maria

    2015-01-01

    Although school is usually considered the most promising institution for the social and economic integration of young people of migration background, the educational outcomes of young people of Ecuadorian background signal a broken promise. Their families, peers, and teachers mediate the effect of the intersections of age, gender, class and…

  19. Design, Construction and Calibration of a Near-Infrared Four-Color Pyrometry System for Laser-Driven High Pressure Experiments

    Science.gov (United States)

    Ali, S. J.; Jeanloz, R.; Collins, G.; Spaulding, D. K.

    2010-12-01

    Current dynamic compression experiments, using both quasi-isentropic and shock-compression, allow access to pressure-temperature states both on and off the principle Hugoniot and over a wide range of conditions of direct relevance to planetary interiors. Such studies necessitate reliable temperature measurements below 4000-5000 K. Such relatively low temperature states are also of particular interest for materials such as methane and water that do not experience much heating under shock compression. In order to measure these temperatures as a function of time across the sample, a four-color, near-infrared pyrometry system is being developed for use at the Janus laser facility (LLNL) with channels at wavelengths of 932nm-1008nm, 1008nm-1108nm, 1108nm-1208nm, and 1208nm-1300nm. Each color band is fiber-coupled to an InGaAs PIN photodiode with a rise time of less than 60 ps, read using an 18 GHz oscilloscope in order to ensure time resolutions of under 200 ps. This will allow for high temporal resolution measurements of laser-driven shock compression experiments with total durations of 5-15 ns as well as correlation with simultaneous time-resolved velocity interferometry and visual-wavelength pyrometry. Calibration of the system is being accomplished using quartz targets, as the EOS for quartz is well known, along with a calibrated integrating sphere of known spectral radiance.

  20. Structure and reactivity of oxalate surface complexes on lepidocrocite derived from infrared spectroscopy, DFT-calculations, adsorption, dissolution and photochemical experiments

    Science.gov (United States)

    Borowski, Susan C.; Biswakarma, Jagannath; Kang, Kyounglim; Schenkeveld, Walter D. C.; Hering, Janet G.; Kubicki, James D.; Kraemer, Stephan M.; Hug, Stephan J.

    2018-04-01

    Oxalate, together with other ligands, plays an important role in the dissolution of iron(hdyr)oxides and the bio-availability of iron. The formation and properties of oxalate surface complexes on lepidocrocite were studied with a combination of infrared spectroscopy (IR), density functional theory (DFT) calculations, dissolution, and photochemical experiments. IR spectra measured as a function of time, concentration, and pH (50-200 μM oxalate, pH 3-7) showed that several surface complexes are formed at different rates and in different proportions. Measured spectra could be separated into three contributions described by Gaussian line shapes, with frequencies that agreed well with the theoretical frequencies of three different surface complexes: an outer-sphere complex (OS), an inner-sphere monodentate mononuclear complex (MM), and a bidentate mononuclear complex (BM) involving one O atom from each carboxylate group. At pH 6, OS was formed at the highest rate. The contribution of BM increased with decreasing pH. In dissolution experiments, lepidocrocite was dissolved at rates proportional to the surface concentration of BM, rather than to the total adsorbed concentration. Under UV-light (365 nm), BM was photolyzed at a higher rate than MM and OS. Although the comparison of measured spectra with calculated frequencies cannot exclude additional possible structures, the combined results allowed the assignment of three main structures with different reactivities consistent with experiments. The results illustrate the importance of the surface speciation of adsorbed ligands in dissolution and photochemical reactions.

  1. Utilization of FADC for reconstruction and analysis of the background data in the Chooz neutrino experiment; Utilisation des FADC pour la reconstruction et l`analyse des donnees de bruit de fond dans l`experience neutrino de Chooz

    Energy Technology Data Exchange (ETDEWEB)

    Veron, Didier [Universite Claude Bernard, 69 - Lyon (France)

    1997-03-25

    This thesis describes a particular contribution to the Chooz experiment. The latter looks for the oscillations, over a distance of 1 km, of antineutrons emitted by two nuclear reactors. The electron-type antineutrinos are detected through their inverse beta interaction with a target`s proton. The neutron is detected through its capture by a gadolinium nucleus revealed by an 8 MeV gamma emission. In the first part we describe the reconstruction of events as simulated by the GIANT software. We show that the positron`s and neutron`s stopping point can actually be reconstructed with an accuracy of 10 and 20 cm respectively. In the second part, we proceed to the analysis of the calibration`s data as recorded with Fast Wave Form Digitizers. This confirms the reliability of the Monte-Carlo results and allows measurement of both the neutrons` capture probability and time by the target gadolinium. The last part deals with the background (reactor turned off) data analysis and the pin-pointing of its various sources. In order to reduce their contribution, we define spatial cuts. These cuts` reliability is validated by analysis of data obtained not only with a neutron source, but also with neutrons issued from cosmic rays. We end up with a background contribution of two to three events per day, about ten times less than the expected neutrino rate at full reactor power. (author) 81 refs., 152 figs.,43 tabs.

  2. History of infrared detectors

    Science.gov (United States)

    Rogalski, A.

    2012-09-01

    This paper overviews the history of infrared detector materials starting with Herschel's experiment with thermometer on February 11th, 1800. Infrared detectors are in general used to detect, image, and measure patterns of the thermal heat radiation which all objects emit. At the beginning, their development was connected with thermal detectors, such as thermocouples and bolometers, which are still used today and which are generally sensitive to all infrared wavelengths and operate at room temperature. The second kind of detectors, called the photon detectors, was mainly developed during the 20th Century to improve sensitivity and response time. These detectors have been extensively developed since the 1940's. Lead sulphide (PbS) was the first practical IR detector with sensitivity to infrared wavelengths up to ˜3 μm. After World War II infrared detector technology development was and continues to be primarily driven by military applications. Discovery of variable band gap HgCdTe ternary alloy by Lawson and co-workers in 1959 opened a new area in IR detector technology and has provided an unprecedented degree of freedom in infrared detector design. Many of these advances were transferred to IR astronomy from Departments of Defence research. Later on civilian applications of infrared technology are frequently called "dual-use technology applications." One should point out the growing utilisation of IR technologies in the civilian sphere based on the use of new materials and technologies, as well as the noticeable price decrease in these high cost technologies. In the last four decades different types of detectors are combined with electronic readouts to make detector focal plane arrays (FPAs). Development in FPA technology has revolutionized infrared imaging. Progress in integrated circuit design and fabrication techniques has resulted in continued rapid growth in the size and performance of these solid state arrays.

  3. Optical polarization: background and camouflage

    Science.gov (United States)

    Škerlind, Christina; Hallberg, Tomas; Eriksson, Johan; Kariis, Hans; Bergström, David

    2017-10-01

    Polarimetric imaging sensors in the electro-optical region, already military and commercially available in both the visual and infrared, show enhanced capabilities for advanced target detection and recognition. The capabilities arise due to the ability to discriminate between man-made and natural background surfaces using the polarization information of light. In the development of materials for signature management in the visible and infrared wavelength regions, different criteria need to be met to fulfil the requirements for a good camouflage against modern sensors. In conventional camouflage design, the aimed design of the surface properties of an object is to spectrally match or adapt it to a background and thereby minimizing the contrast given by a specific threat sensor. Examples will be shown from measurements of some relevant materials and how they in different ways affect the polarimetric signature. Dimensioning properties relevant in an optical camouflage from a polarimetric perspective, such as degree of polarization, the viewing or incident angle, and amount of diffuse reflection, mainly in the infrared region, will be discussed.

  4. Validating an infrared thermal switch as a novel access technology

    Directory of Open Access Journals (Sweden)

    Memarian Negar

    2010-08-01

    Full Text Available Abstract Background Recently, a novel single-switch access technology based on infrared thermography was proposed. The technology exploits the temperature differences between the inside and surrounding areas of the mouth as a switch trigger, thereby allowing voluntary switch activation upon mouth opening. However, for this technology to be clinically viable, it must be validated against a gold standard switch, such as a chin switch, that taps into the same voluntary motion. Methods In this study, we report an experiment designed to gauge the concurrent validity of the infrared thermal switch. Ten able-bodied adults participated in a series of 3 test sessions where they simultaneously used both an infrared thermal and conventional chin switch to perform multiple trials of a number identification task with visual, auditory and audiovisual stimuli. Participants also provided qualitative feedback about switch use. User performance with the two switches was quantified using an efficiency measure based on mutual information. Results User performance (p = 0.16 and response time (p = 0.25 with the infrared thermal switch were comparable to those of the gold standard. Users reported preference for the infrared thermal switch given its non-contact nature and robustness to changes in user posture. Conclusions Thermal infrared access technology appears to be a valid single switch alternative for individuals with disabilities who retain voluntary mouth opening and closing.

  5. The new Mediterranean background monitoring station of Ersa, Cape Corsica: A long term Observatory component of the Chemistry-Aerosol Mediterranean Experiment (ChArMEx)

    Science.gov (United States)

    Dulac, Francois

    2013-04-01

    The Chemistry-Aerosol Mediterranean Experiment (ChArMEx, http://charmex.lsce.ipsl.fr/) is a French initiative supported by the MISTRALS program (Mediterranean Integrated Studies at Regional And Locals Scales, http://www.mistrals-home.org). It aims at a scientific assessment of the present and future state of the atmospheric environment in the Mediterranean Basin, and of its impacts on the regional climate, air quality, and marine biogeochemistry. The major stake is an understanding of the future of the Mediterranean region in a context of strong regional anthropogenic and climatic pressures. The target of ChArMEx is short-lived particulate and gaseous tropospheric trace species which are the cause of poor air quality events, have two-way interactions with climate, or impact the marine biogeochemistry. In order to fulfill these objectives, important efforts have been put in 2012 in order to implement the infrastructure and instrumentation for a fully equipped background monitoring station at Ersa, Cape Corsica, a key location at the crossroads of dusty southerly air masses and polluted outflows from the European continent. The observations at this station began in June 2012 (in the context of the EMEP / ACTRIS / PEGASOS / ChArMEx campaigns). A broad spectrum of aerosol properties is also measured at the station, from the chemical composition (off-line daily filter sampling in PM2.5/PM10, on-line Aerosol Chemical Speciation Monitor), ground optical properties (extinction/absorption/light scattering coeff. with 1-? CAPS PMex monitor, 7-? Aethalometer, 3-? Nephelometer), integrated and vertically resolved optical properties (4-? Cimel sunphotometer and LIDAR, respective), size distribution properties (N-AIS, SMPS, APS, and OPS instruments), mass (PM1/PM10 by TEOM/TEOM-FDMS), hygroscopicity (CCN), as well as total insoluble deposition. So far, real-time measurement of reactive gases (O3, CO, NO, NO2), and off-line VOC measurements (cylinders, cartridges) are also

  6. The Cosmic Microwave Background

    Directory of Open Access Journals (Sweden)

    Jones Aled

    1998-01-01

    Full Text Available We present a brief review of current theory and observations of the cosmic microwave background (CMB. New predictions for cosmological defect theories and an overview of the inflationary theory are discussed. Recent results from various observations of the anisotropies of the microwave background are described and a summary of the proposed experiments is presented. A new analysis technique based on Bayesian statistics that can be used to reconstruct the underlying sky fluctuations is summarised. Current CMB data is used to set some preliminary constraints on the values of fundamental cosmological parameters $Omega$ and $H_circ$ using the maximum likelihood technique. In addition, secondary anisotropies due to the Sunyaev-Zel'dovich effect are described.

  7. An Empirical Determination of the Intergalactic Background Light Using Near-Infrared Deep Galaxy Survey Data Out to 5 Micrometers and the Gamma-Ray Opacity of the Universe

    Science.gov (United States)

    Scully, Sean T.; Malkan, Matthew A.; Stecker, Floyd W.

    2014-01-01

    We extend our previous model-independent determination of the intergalactic background light, based purely on galaxy survey data, out to a wavelength of 5 micrometers. Our approach enables us to constrain the range of photon densities, based on the uncertainties from observationally determined luminosity densities and colors. We further determine a 68% confidence upper and lower limit on the opacity of the universe to gamma-rays up to energies of 1.6/(1 + z) terraelectron volts. A comparison of our lower limit redshift-dependent opacity curves to the opacity limits derived from the results of both ground-based air Cerenkov telescope and Fermi-LAT observations of PKS 1424+240 allows us to place a new upper limit on the redshift of this source, independent of IBL modeling.

  8. Bridging the gap between public health and primary care in prevention of cardiometabolic diseases: background of and experiences with the Prevention Consultation in The Netherlands.

    NARCIS (Netherlands)

    Assendelft, W.J.J.; Nielen, M.M.J.; Hettinga, D.M.; Meer, V. van der; Vliet, M. van; Drenthen, A.J.M.; Schellevis, F.G.; Oosterhout, M.J.W. van

    2012-01-01

    BACKGROUND: There is an increasing need for programmatic prevention of cardiometabolic diseases (cardiovascular disease, type 2 diabetes and chronic kidney disease). Therefore, in the Netherlands, a prevention programme linked to primary care has been developed. This initiative was supported by the

  9. Sentinel Node Mapping Using Indocyanine Green and Near-infrared Fluorescence Imaging Technology for Uterine Malignancies: Preliminary Experience With the Da Vinci Xi System.

    Science.gov (United States)

    Siesto, Gabriele; Romano, Fabrizio; Fiamengo, Barbara; Vitobello, Domenico

    2016-01-01

    Sentinel lymph node (SLN) mapping has emerged as the new frontier for the surgical staging of apparently early-stage cervical and endometrial cancer. Different colorimetric and radioactive tracers, alone and in combination, have been proposed with encouraging results. Fluorometric mapping using indocyanine green (ICG) appears to be a suitable and attractive alternative to provide reliable staging [1-4]. In this video, we present the technique of SLN mapping in 2 cases (1 endometrial and 1 cervical cancer, respectively) using ICG and the near-infrared technology provided by the newest Da Vinci Xi robotic system (Intuitive Surgical Inc., Sunnyvale, CA). Together we report the results of our preliminary experience on the first 20 cases performed. The new robotic Da Vinci Xi system was available at our institution since May 2015. Upon institutional review board/ethical committee approval, all consecutive patients with early-stage endometrial and cervical cancer who were judged suitable for robotic surgery have been enrolled for SLN mapping with ICG. We adopted the Memorial Sloan Kettering Cancer Center SLN algorithm; the tracer was delivered into the cervix in all cases. Four milliliters (1.25 mg/mL) of ICG was injected divided into the 3- and 9-o'clock positions of the cervix alone, with 1 mL deep into the stroma and 1 mL submucosally at the skin incision. Sentinel lymph nodes were examined with a protocol including both ultrastaging with immunohistochemistry [3] and 1-step nucleic acid amplification assay [5,6] under a parallel protocol of study. During the study period, 20 cases were managed; 14 and 6 patients had endometrial and cervical cancer, respectively. SLN was detected in all cases (20/20, 100%). Bilateral SLNs were detected in 17 of 20 (85.0%) cases. Based on preoperative and intraoperative findings, 13 (65.0%) patients received systematic pelvic lymphadenectomy after SLN mapping. Three (15.0%) patients had microscopic nodal metastases on SLN. No

  10. THE DISTORTION OF THE COSMIC MICROWAVE BACKGROUND SPECTRUM DUE TO INTERGALACTIC DUST

    Energy Technology Data Exchange (ETDEWEB)

    Imara, Nia; Loeb, Abraham, E-mail: nimara@cfa.harvard.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2016-07-10

    Infrared emission from intergalactic dust might compromise the ability of future experiments to detect subtle spectral distortions in the Cosmic Microwave Background (CMB) from the early universe. We provide the first estimate of foreground contamination of the CMB signal due to diffuse dust emission in the intergalactic medium. We use models of the extragalactic background light to calculate the intensity of intergalactic dust emission and find that emission by intergalactic dust at z ≲ 0.5 exceeds the sensitivity of the planned Primordial Inflation Explorer to CMB spectral distortions by 1–3 orders of magnitude. In the frequency range ν = 150–2400 GHz, we place an upper limit of 0.06% on the contribution to the far-infrared background from intergalactic dust emission.

  11. Design and performance of combined infrared canopy and belowground warming in the B4WarmED (Boreal Forest Warming at an Ecotone in Danger) experiment.

    Science.gov (United States)

    Rich, Roy L; Stefanski, Artur; Montgomery, Rebecca A; Hobbie, Sarah E; Kimball, Bruce A; Reich, Peter B

    2015-06-01

    Conducting manipulative climate change experiments in complex vegetation is challenging, given considerable temporal and spatial heterogeneity. One specific challenge involves warming of both plants and soils to depth. We describe the design and performance of an open-air warming experiment called Boreal Forest Warming at an Ecotone in Danger (B4WarmED) that addresses the potential for projected climate warming to alter tree function, species composition, and ecosystem processes at the boreal-temperate ecotone. The experiment includes two forested sites in northern Minnesota, USA, with plots in both open (recently clear-cut) and closed canopy habitats, where seedlings of 11 tree species were planted into native ground vegetation. Treatments include three target levels of plant canopy and soil warming (ambient, +1.7°C, +3.4°C). Warming was achieved by independent feedback control of voltage input to aboveground infrared heaters and belowground buried resistance heating cables in each of 72-7.0 m(2) plots. The treatments emulated patterns of observed diurnal, seasonal, and annual temperatures but with superimposed warming. For the 2009 to 2011 field seasons, we achieved temperature elevations near our targets with growing season overall mean differences (∆Tbelow ) of +1.84°C and +3.66°C at 10 cm soil depth and (∆T(above) ) of +1.82°C and +3.45°C for the plant canopies. We also achieved measured soil warming to at least 1 m depth. Aboveground treatment stability and control were better during nighttime than daytime and in closed vs. open canopy sites in part due to calmer conditions. Heating efficacy in open canopy areas was reduced with increasing canopy complexity and size. Results of this study suggest the warming approach is scalable: it should work well in small-statured vegetation such as grasslands, desert, agricultural crops, and tree saplings (<5 m tall). © 2015 John Wiley & Sons Ltd.

  12. Application of open-path Fourier transform infrared spectroscopy for atmospheric monitoring of a CO2 back-production experiment at the Ketzin pilot site (Germany).

    Science.gov (United States)

    Sauer, Uta; Borsdorf, H; Dietrich, P; Liebscher, A; Möller, I; Martens, S; Möller, F; Schlömer, S; Schütze, C

    2018-02-03

    During a controlled "back-production experiment" in October 2014 at the Ketzin pilot site, formerly injected CO 2 was retrieved from the storage formation and directly released to the atmosphere via a vent-off stack. Open-path Fourier transform infrared (OP FTIR) spectrometers, on-site meteorological parameter acquisition systems, and distributed CO 2 point sensors monitored gas dispersion processes in the near-surface part of the atmospheric boundary layer. The test site provides a complex and challenging mosaic-like surface setting for atmospheric monitoring which can also be found at other storage sites. The main aims of the atmospheric monitoring of this experiment were (1) to quantify temporal and spatial variations in atmospheric CO 2 concentrations around the emitting vent-off stack and (2) to test if and how atmospheric monitoring can cope with typical environmental and operational challenges. A low environmental risk was encountered during the whole CO 2 back-production experiment. The study confirms that turbulent wind conditions favor atmospheric mixing processes and are responsible for rapid dilution of the released CO 2 leading to decreased detectability at all sensors. In contrast, calm and extremely stable wind conditions (especially occurring during the night) caused an accumulation of gases in the near-ground atmospheric layer with the highest amplitudes in measured gas concentration. As an important benefit of OP FTIR spectroscopic measurements and their ability to detect multiple gas species simultaneously, emission sources could be identified to a much higher certainty. Moreover, even simulation models using simplified assumptions help to find suitable monitoring network designs and support data analysis for certain wind conditions in such a complex environment.

  13. Moisture measurement in the iron and steel industry: experience with nuclear moisture measurements in coke, and studies of infrared moisture measurement of iron ore mixtures

    International Nuclear Information System (INIS)

    Beumer, J.A.; Wouters, M.

    1976-01-01

    In the heavy iron-making industry there are several processes for which it is necessary to measure on-line the moisture content of certain process materials, especially in the field of iron ore preparation and blast furnace practice. Two examples are given. (1) Experience with nuclear moisture-measurements in coke covers a period of ten years in which eight measuring systems have been installed in the weighing hoppers of blast furnaces. The standard deviation is about 0.7% moisture in the range 0 to 15% moisture. The way the method is used, the safety measures and the difficulties encountered, especially the effect on recalibration of neutron-absorbing materials in photomultipliers are described. (2) The application of infrared absorption to the study of moisture measurment or iron ore mixtures is described. With an ore mixture for pellets manufacture, a rather dark ore mixture, problems have arisen concerning the sensitivity. The reference and measuring wavelengths now in use are 2.51 and 2.95 μm. In this case the absorption of the energy is rather high. The results may be improved by using quartz optics instead of the normal Pyrex ones, as the cut-off wavelength of Pyrex is about 3 μm. Variations due to colour and specific surface have been studied. As the accuracy required is +- 0.1% moisture in the range 8 to 12% moisture, these variations need to be eliminated. (author)

  14. Characterization of silicon micro-strip sensors with a pulsed infra-red laser system for the CBM experiment at FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Pradeep [Goethe University, Frankfurt am Main (Germany); GSI Helmholtz Center for Heavy Ion Research GmbH, Darmstadt (Germany); Eschke, Juergen [GSI Helmholtz Center for Heavy Ion Research GmbH, Darmstadt (Germany); Facility for Anti-proton and Ion Research, GmbH, Darmstadt (Germany); Collaboration: CBM-Collaboration

    2015-07-01

    The Silicon Tracking System (STS) of the CBM experiment at FAIR is composed of 8 tracking stations comprising of 1292 double-sided silicon micro-strip sensors. A Laser Test System (LTS) has been developed for the quality assurance of prototype sensors. The aim is to scan sensors with a pulsed infra-red laser driven by step motor to determine the charge sharing in-between strips and to measure qualitative uniformity of the sensor response over the whole active area. Several prototype sensors with strip pitch of 50 and 58 μm have been tested, as well as a prototype module with realistic mechanical arrangement of sensor and read-out cables. The LTS is designed to measure sensor response in an automatized procedure across the sensor with focused laser beam (spot-size ∼ 12 μm, wavelength = 1060 nm). The pulse with duration (∼ 10 ns) and power (∼ 5 mW) of the laser pulses is selected such, that the absorption of the laser light in the 300 μm thick silicon sensors produces a number of about 24000 electrons, which is similar to the charge created by minimum ionizing particles (MIP) in these sensors. Results from laser scans of prototype sensors and detector module are reported.

  15. Radiation budget studies using collocated observations from advanced Very High Resolution Radiometer, High-Resolution Infrared Sounder/2, and Earth Radiation Budget Experiment instruments

    Science.gov (United States)

    Ackerman, Steven A.; Frey, Richard A.; Smith, William L.

    1992-01-01

    Collocated observations from the Advanced Very High Resolution Radiometer (AVHRR), High-Resolution Infrared Sounder/2 (HIRS/2), and Earth Radiation Budget Experiment (ERBE) instruments onboard the NOAA 9 satellite are combined to describe the broadband and spectral radiative properties of the earth-atmosphere system. Broadband radiative properties are determined from the ERBE observations, while spectral properties are determined from the HIRS/2 and AVHRR observations. The presence of clouds, their areal coverage, and cloud top pressure are determined from a combination of the HIRS/2 and the AVHRR observations. The CO2 slicing method is applied to the HIRS/2 to determine the presence of upper level clouds and their effective emissivity. The AVHRR data collocated within the HIRS/2 field of view are utilized to determine the uniformity of the scene and retrieve sea surface temperature. Changes in the top of the atmosphere longwave and shortwave radiative energy budgets, and the spectral distribution of longwave radiation are presented as a function of cloud amount and cloud top pressure. The radiative characteristics of clear sky conditions over oceans are presented as a function of sea surface temperature and atmospheric water vapor structure.

  16. submitter Study of possible Supersymmetric processes and Mini Black Hole production and comparison to background events with high transverse energy in the ATLAS experiment

    CERN Document Server

    Melamed-Katz, Arie

    2009-01-01

    The ATLAS detector, which was installed at one of the interaction points of the Large Hadron Collider (LHC), has the capability to discover 'new physics' beyond the Standard Model (SM) already during its first year of operation. In this work an assessment of ATLAS capabilities regarding the detection of some 'new physics' signals is performed. In the course of this research all relevant SM background sources were produced. These sources were studied with several simulation tools and the results are compared. In the scope of these background studies, a verification procedure that relies on expected SM production rates was developed. This procedure is able to distinguish between new physics and a faked one originating in malfunctioning detector. Supersymmetry (SUSY) is one of the best candidates for the theory 'beyond the Standard Model'. It predicts the existence of new symmetry between bosons and fermions, and assumes a new fermion partner for each SM boson and a new boson partner for each SM fermion. A maj...

  17. Mid-infrared picosecond pump-dump-probe and pump-repump-probe experiments to resolve a ground-state intermediate in cyanobacterial phytochrome Cph1.

    Science.gov (United States)

    van Wilderen, Luuk J G W; Clark, Ian P; Towrie, Michael; van Thor, Jasper J

    2009-12-24

    Multipulse picosecond mid-infrared spectroscopy has been used to study photochemical reactions of the cyanobacterial phytochrome photoreceptor Cph1. Different photophysical schemes have been discussed in the literature to describe the pathways after photoexcitation, particularly, to identify reaction phases that are linked to photoisomerisation and electronic decay in the 1566-1772 cm(-1) region that probes C=C and C=O stretching modes of the tetrapyrrole chromophore. Here, multipulse spectroscopy is employed, where, compared to conventional visible pump-mid-infrared probe spectroscopy, an additional visible pulse is incorporated that interacts with populations that are evolving on the excited- and ground-state potential energy surfaces. The time delays between the pump and the dump pulse are chosen such that the dump pulse interacts with different phases in the reaction process. The pump and dump pulses are at the same wavelength, 640 nm, and are resonant with the Pr ground state as well as with the excited state and intermediates. Because the dump pulse additionally pumps the remaining, partially recovered, and partially oriented ground-state population, theory is developed for estimating the fraction of excited-state molecules. The calculations take into account the model-dependent ground-state recovery fraction, the angular dependence of the population transfer resulting from the finite bleach that occurs with linearly polarized intense femtosecond optical excitation, and the partially oriented population for the dump field. Distinct differences between the results from the experiments that use a 1 or a 14 ps dump time favor a branching evolution from S1 to an excited state or reconfigured chromophore and to a newly identified ground-state intermediate (GSI). Optical dumping at 1 ps shows the instantaneous induced absorption of a delocalized C=C stretching mode at 1608 cm(-1), where the increased cross section is associated with the electronic ground

  18. LHCb: Beam and Background Monitoring and the Upgrade of the Timing and Fast Control System of the LHCb experiment at CERN

    CERN Multimedia

    Alessio, F

    2009-01-01

    The LHCb experiment at CERN is preparing for first real data taking, foreseen by the end of the year 2009 with the start-up of the LHC. A large amount of work of commissioning, tests and improvements of the full detector has been done in order to optimize its performance. During my first year as a Doctoral Student at CERN, I have been working on the timing and readout control of the LHCb experiment in the frame of the LHCb Online group. The group is responsible for the full data acquisition of the LHCb experiment, from the Front-End Electronics (FEE) to the storage of the data for offline analysis, as well as the Timing and Fast Control (TFC) system. The latter controls and distributes centrally timing and trigger information, as well as synchronous and asynchronous commands to the readout system. It is also responsible for receiving and adjusting the bunch and orbit clocks of the LHC machine and distributing it to the electronics of the whole experiment. It is of vital importance to assure that the timing o...

  19. Clearance of materials, some experience from the UK - Clearing a recent building, a chance to get as much material out as indistinguishable from background. A rare opportunity

    International Nuclear Information System (INIS)

    Burgess, Peter; Fisher, Alan

    2014-01-01

    This poster will illustrate the methods used in the UK to clear materials from a relatively modern building with good history. Some materials were cleared as clean, i.e. there was no reasonable chance of contamination given where they were and how they had been used. Other materials were cleared as Out of Scope, i.e. they complied with the relevant UK legislation to be considered in law as non-radioactive. The first group was subjected to limited confirmation measurements whereas the latter were carefully monitored. The aim was to set up, for each object, a monitoring method which took account of the fingerprint, the material mass per unit area and its influence on background. The capacity of the monitoring method was described in terms of Maximum Missable Activity and the aim was to set up methods which gave MMAs which gave confident sentencing but limited the time taken. The project was very successful. (authors)

  20. Infrared thermal annealing device

    International Nuclear Information System (INIS)

    Gladys, M.J.; Clarke, I.; O'Connor, D.J.

    2003-01-01

    A device for annealing samples within an ultrahigh vacuum (UHV) scanning tunneling microscopy system was designed, constructed, and tested. The device is based on illuminating the sample with infrared radiation from outside the UHV chamber with a tungsten projector bulb. The apparatus uses an elliptical mirror to focus the beam through a sapphire viewport for low absorption. Experiments were conducted on clean Pd(100) and annealing temperatures in excess of 1000 K were easily reached

  1. High-sensitive spectrometer of fast neutrons and the results of fast neutron background flux measurements at the gallium-germanium solar neutrino experiment (SAGE)

    International Nuclear Information System (INIS)

    Abdurashitov, D.N.; Gavrin, V.N.; Kalikhov, A.V.; Matushko, V.L.; Shikhin, A.A.; Yants, V.E.; Zaborskaya, O.S.

    2001-01-01

    The principle of operation, design, registration system and main characteristics of a fast neutron spectrometer are described. The spectrometer is intended for direct measurements of ultra-low fluxes of fast neutrons. It is sensitive to neutron fluxes of 10 -7 cm -2 · s -1 and lower. The detection efficiency of fast neutrons with simultaneous energy measurement was determined from Monte-Carlo simulation to be equal to 0.11 ± 0.01. The background counting rate in the detector corresponds to a neutron flux of (6.5 ± 2.1) · 10 -7 cm -2 · s -1 in the range of 1.0-11.0 MeV. The natural neutron flux from the surrounding mine rock at the depth of 4600 meters of water equivalent was measured to be (7.3 ± 2.4) · 10 -7 cm -2 · s -1 in the interval 1.0 -11.0 MeV. The flux of fast neutrons in the SAGE main room was measured to be 2.3 · 10 -7 cm -2 · s -1 in 1.0 - 11.0 MeV energy range

  2. High-sensitive spectrometer of fast neutrons and the results of fast neutron background flux measurements at the Gallium-Germanium Solar Neutrino Experiment

    CERN Document Server

    Abdurashitov, J N; Kalikhov, A V; Matushko, V L; Shikhin, A A; Yants, V E; Zaborskaia, O S

    2002-01-01

    The principle of operation, design, registration system and main characteristics of a fast neutron spectrometer are described. The spectrometer is intended for direct measurements of ultra low fluxes of fast neutrons. It is sensitive to neutron fluxes of 10 sup - sup 7 cm sup - sup 2 s sup - sup 1 and lower. The detection efficiency of fast neutrons with simultaneous energy measurement was determined from Monte-Carlo simulation to be equal to 0.11+-0.01. The background counting rate in the detector corresponds to a neutron flux of (6.5+-2.1)x10 sup - sup 7 cm sup - sup 2 s sup - sup 1 in the range 1.0-11.0 MeV. The natural neutron flux from the surrounding mine rock at the depth of 4600 m of water equivalent was measured to be (7.3+-2.4)x10 sup - sup 7 cm sup - sup 2 s sup - sup 1 in the range 1.0-11.0 MeV. The flux of fast neutrons in the SAGE main room was measured to be <2.3x10 sup - sup 7 cm sup - sup 2 s sup - sup 1 in 1.0-11.0 MeV energy range.

  3. Analysis method for the search for neutrinoless double beta decay in the NEMO3 experiment: study of the background and first results

    International Nuclear Information System (INIS)

    Etienvre, A.I.

    2003-04-01

    The NEMO3 detector, installed in the Frejus Underground Laboratory, is dedicated to the study of neutrinoless double beta decay: the observation of this process would sign the massive and Majorana nature of neutrino. The experiment consists in very thin central source foils (the total mass is equal to 10 kg), a tracking detector made of drift cells operating in Geiger mode, a calorimeter made of plastic scintillators associated to photomultipliers, a coil producing a 30 gauss magnetic field and two shields, dedicated to the reduction of the γ-ray and neutron fluxes. In the first part, I describe the implications of several mechanisms, related to trilinear R-parity violation, on double beta decay. The second part is dedicated to a detailed study of the tracking detector of the experiment: after a description of the different working tests, I present the determination of the characteristics of the tracking reconstruction (transverse and longitudinal resolution, by Geiger cell and precision on vertex determination, charge recognition). The last part corresponds to the analysis of the data taken by the experiment. On the one hand, an upper limit on the Tl 208 activity of the sources has been determined: it is lower than 68 mBq/kg, at 90% of confidence level. On the other hand, I have developed and tested on these data a method in order to analyse the neutrinoless double beta decay signal; this method is based on a maximum of likelihood using all the available information. Using this method, I could determine a first and very preliminary upper limit on the effective mass of the neutrino. (author)

  4. Cosmic microwave background, where next?

    CERN Multimedia

    CERN. Geneva

    2009-01-01

    Ground-based, balloon-borne and space-based experiments will observe the Cosmic Microwave Background in greater details to address open questions about the origin and the evolution of the Universe. In particular, detailed observations the polarization pattern of the Cosmic Microwave Background radiation have the potential to directly probe physics at the GUT scale and illuminate aspects of the physics of the very early Universe.

  5. Activation of the maternal caregiving system by childhood fever – a qualitative study of the experiences made by mothers with a German or a Turkish background in the care of their children

    Science.gov (United States)

    2013-01-01

    Background Childhood fever represents a frequent cause to consult a primary care physician. “Fever phobia” describes a fearful and irrational view of fever shared by many parents with different cultural backgrounds. The study aims to explain the experiences of mothers of children having a fever and to analyze the role of the mothers’ cultural background with regard to their experiences by comparing the accounts of mothers with a German with those from a Turkish background. Disease and context specific knowledge about the influence of culture can be important for effective counselling. Methods We applied a qualitative approach using in-depth interviews with 11 mothers with a Turkish and 9 with a German background living in Germany. The interviews were conducted at the participants´ homes from May to October 2008. Data was audio-recorded and transcribed verbatim. Grounded Theory was used as a framing methodology including open, axial and selective coding. Analysis was performed in a group with members of different professional and cultural backgrounds. Results Mothers experienced their child’s fever not merely as elevated temperature but as a potentially dangerous event. A deeply rooted urge to protect the child from harm was central to all participants’ experience. The caregiving system model offers a good theoretical foundation to explain the findings as it incorporates the unique relational quality of care giving mothers to their children. The cultural background represents an important context variable influencing the explanatory models and strategies of dealing with fever. The identified culturally influenced concepts sometimes match and sometimes conflict with medical knowledge. Conclusion By applying the caregiving system model which is a part of attachment theory (Bowlby) maternal actions can be understood as an understandable attempt to protect the child from harm. The mothers´ decisions what to do when a child has a fever can be culturally

  6. QCD background estimation for Supersymmetry searches with jets and missing transverse momentum with the ATLAS experiment at the Large Hadron Collider

    CERN Document Server

    Stoerig, Kathrin

    Some of the most interesting questions mankind might ask are closely related to the field of astro- and particle physics: What are the fundamental building blocks of our universe and how do they interact? Will there eventually be a theory that can describe everything? During the last decades, particle collision experiments unraveled various aspects of these mysteries - and a very successful theory emerged: the Standard Model (SM) of particle physics: As of today’s knowledge, matter consists of fermions, the quarks and the leptons. Among these, four fundamental interactions are known: the strong, the weak, the electromagnetic and the gravitational force. These interactions are mediated by bosons (force carriers). While the SM describes the first three interactions with high precision, various fundamental questions remain unanswered - such as the structure in the SM itself, the origin of dark matter/energy and the matter-/antimatter asymmetry. One aesthetically appealing solution is Supersymmetry (SUSY), whic...

  7. AXION DECAY AND ANISOTROPY OF NEAR-IR EXTRAGALACTIC BACKGROUND LIGHT

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Yan; Chen, Xuelei [National Astronomical Observatories, Chinese Academy of Sciences, Beijing, 100012 (China); Cooray, Asantha; Mitchell-Wynne, Ketron [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Zemcov, Michael [Center for Detectors, School of Physics and Astronomy, Rochester Institute of Technology, Rochester, NY 14623 (United States); Smidt, Joseph [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2016-07-10

    The extragalactic background light (EBL) is composed of the cumulative radiation from all galaxies and active galactic nuclei over cosmic history. In addition to point sources, the EBL also contains information from diffuse sources of radiation. The angular power spectra of the near-infrared intensities could contain additional signals, and a complete understanding of the nature of the infrared (IR) background is still lacking in the literature. Here we explore the constraints that can be placed on particle decays, especially candidate dark matter (DM) models involving axions that trace DM halos of galaxies. Axions with a mass around a few electronvolts will decay via two photons with wavelengths in the near-IR band and will leave a signature in the IR background intensity power spectrum. Using recent power spectra measurements from the Hubble Space Telescope and the Cosmic Infrared Background Experiment, we find that the 0.6–1.6 μ m power spectra can be explained by axions with masses around 4 eV. The total axion abundance Ω{sub a} ≃ 0.05, and it is comparable to the baryon density of the universe. The suggested mean axion mass and abundance are not ruled out by existing cosmological observations. Interestingly, the axion model with a mass distribution is preferred by the data, which cannot be explained by the standard quantum chromodynamics theory and needs further discussion.

  8. Techniques and Analysis of Thermal Infrared Camouflage in Foliated Backgrounds

    Science.gov (United States)

    1977-01-06

    is the long wavelength (terrestial) insolation J is the solar wavelength radiosity of the ith surface J is the terrestial wavelength radiosity of the...reflectance Pt is the terrestial wavelength reflectance and J T is the solar wavelength transmittance. The radiosities were evaluated in terms of the boundary

  9. COBE DIRBE near-infrared polarimetry of the zodiacal light: Initial results

    Science.gov (United States)

    Berriman, G. B.; Boggess, N. W.; Hauser, M. G.; Kelsall, T.; Lisse, C. M.; Moseley, S. H.; Reach, W. T.; Silverberg, R. F.

    1994-01-01

    This Letter describes near-infrared polarimetry of the zodiacal light at 2.2 micrometers, measured with the Diffuse Infrared Background Experiment (DIRBE) aboard the Cosmic Background Explorer (COBE) spacecraft. The polarization is due to scattering of sunlight. The polarization vector is perpendicular to the scattering plane, and its observed amplitude on the ecliptic equator at an elongation of 90 deg and ecliptic longitude of 10 deg declines from 12.0 +/- 0.4% at 1.25 micrometers to 8.0 +/- 0.6% at 3.5 micrometers (cf. 16% in the visible); the principal source of uncertainty is photometric noise due to stars. The observed near-infrared colors at this location are redder than Solar, but at 3.5 micrometers this is due at least in part to the thermal emission contribution from the interplanetary dust. Mie theory calculations show that both polarizations and colors are important in constraining models of interplanetary dust.

  10. Infrared Heaters

    Science.gov (United States)

    1979-01-01

    The heating units shown in the accompanying photos are Panelbloc infrared heaters, energy savers which burn little fuel in relation to their effective heat output. Produced by Bettcher Manufacturing Corporation, Cleveland, Ohio, Panelblocs are applicable to industrial or other facilities which have ceilings more than 12 feet high, such as those pictured: at left the Bare Hills Tennis Club, Baltimore, Maryland and at right, CVA Lincoln- Mercury, Gaithersburg, Maryland. The heaters are mounted high above the floor and they radiate infrared energy downward. Panelblocs do not waste energy by warming the surrounding air. Instead, they beam invisible heat rays directly to objects which absorb the radiation- people, floors, machinery and other plant equipment. All these objects in turn re-radiate the energy to the air. A key element in the Panelbloc design is a coating applied to the aluminized steel outer surface of the heater. This coating must be corrosion resistant at high temperatures and it must have high "emissivity"-the ability of a surface to emit radiant energy. The Bettcher company formerly used a porcelain coating, but it caused a production problem. Bettcher did not have the capability to apply the material in its own plant, so the heaters had to be shipped out of state for porcelainizing, which entailed extra cost. Bettcher sought a coating which could meet the specifications yet be applied in its own facilities. The company asked The Knowledge Availability Systems Center, Pittsburgh, Pennsylvania, a NASA Industrial Applications Center (IAC), for a search of NASA's files

  11. Activation of the maternal caregiving system by childhood fever--a qualitative study of the experiences made by mothers with a German or a Turkish background in the care of their children.

    Science.gov (United States)

    Langer, Thorsten; Pfeifer, Miriam; Soenmez, Aynur; Kalitzkus, Vera; Wilm, Stefan; Schnepp, Wilfried

    2013-03-18

    Childhood fever represents a frequent cause to consult a primary care physician. "Fever phobia" describes a fearful and irrational view of fever shared by many parents with different cultural backgrounds. The study aims to explain the experiences of mothers of children having a fever and to analyze the role of the mothers' cultural background with regard to their experiences by comparing the accounts of mothers with a German with those from a Turkish background. Disease and context specific knowledge about the influence of culture can be important for effective counselling. We applied a qualitative approach using in-depth interviews with 11 mothers with a Turkish and 9 with a German background living in Germany. The interviews were conducted at the participants' homes from May to October 2008. Data was audio-recorded and transcribed verbatim. Grounded Theory was used as a framing methodology including open, axial and selective coding. Analysis was performed in a group with members of different professional and cultural backgrounds. Mothers experienced their child's fever not merely as elevated temperature but as a potentially dangerous event. A deeply rooted urge to protect the child from harm was central to all participants' experience. The caregiving system model offers a good theoretical foundation to explain the findings as it incorporates the unique relational quality of care giving mothers to their children. The cultural background represents an important context variable influencing the explanatory models and strategies of dealing with fever. The identified culturally influenced concepts sometimes match and sometimes conflict with medical knowledge. By applying the caregiving system model which is a part of attachment theory (Bowlby) maternal actions can be understood as an understandable attempt to protect the child from harm. The mothers' decisions what to do when a child has a fever can be culturally influenced. This may lead either to a frequent use of

  12. Cosmic Microwave Background Timeline

    Science.gov (United States)

    Cosmic Microwave Background Timeline 1934 : Richard Tolman shows that blackbody radiation in an will have a blackbody cosmic microwave background with temperature about 5 K 1955: Tigran Shmaonov anisotropy in the cosmic microwave background, this strongly supports the big bang model with gravitational

  13. Space Infrared Telescope Facility (SIRTF) science instruments

    International Nuclear Information System (INIS)

    Ramos, R.; Hing, S.M.; Leidich, C.A.; Fazio, G.; Houck, J.R.

    1989-01-01

    Concepts of scientific instruments designed to perform infrared astronomical tasks such as imaging, photometry, and spectroscopy are discussed as part of the Space Infrared Telescope Facility (SIRTF) project under definition study at NASA/Ames Research Center. The instruments are: the multiband imaging photometer, the infrared array camera, and the infrared spectograph. SIRTF, a cryogenically cooled infrared telescope in the 1-meter range and wavelengths as short as 2.5 microns carrying multiple instruments with high sensitivity and low background performance, provides the capability to carry out basic astronomical investigations such as deep search for very distant protogalaxies, quasi-stellar objects, and missing mass; infrared emission from galaxies; star formation and the interstellar medium; and the composition and structure of the atmospheres of the outer planets in the solar sytem. 8 refs

  14. Background Characterization Techniques For Pattern Recognition Applications

    Science.gov (United States)

    Noah, Meg A.; Noah, Paul V.; Schroeder, John W.; Kessler, Bernard V.; Chernick, Julian A.

    1989-08-01

    The Department of Defense has a requirement to investigate technologies for the detection of air and ground vehicles in a clutter environment. The use of autonomous systems using infrared, visible, and millimeter wave detectors has the potential to meet DOD's needs. In general, however, the hard-ware technology (large detector arrays with high sensitivity) has outpaced the development of processing techniques and software. In a complex background scene the "problem" is as much one of clutter rejection as it is target detection. The work described in this paper has investigated a new, and innovative, methodology for background clutter characterization, target detection and target identification. The approach uses multivariate statistical analysis to evaluate a set of image metrics applied to infrared cloud imagery and terrain clutter scenes. The techniques are applied to two distinct problems: the characterization of atmospheric water vapor cloud scenes for the Navy's Infrared Search and Track (IRST) applications to support the Infrared Modeling Measurement and Analysis Program (IRAMMP); and the detection of ground vehicles for the Army's Autonomous Homing Munitions (AHM) problems. This work was sponsored under two separate Small Business Innovative Research (SBIR) programs by the Naval Surface Warfare Center (NSWC), White Oak MD, and the Army Material Systems Analysis Activity at Aberdeen Proving Ground MD. The software described in this paper will be available from the respective contract technical representatives.

  15. Data-driven background predictions for a search of direct gluino pair production in the single-lepton final state using 13 TeV pp-collisions at the CMS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Lobanov, Artur; Seitz, Claudia; Melzer-Pellmann, Isabell [DESY, Hamburg (Germany)

    2016-07-01

    We present a search for direct gluino-pair production in events with a single lepton using 13 TeV pp-collisions at the CMS experiment. This final state is characterised by high multiplicities of jets and b-quark jets, as well as a large scalar sum of all jet transverse momenta, and a large scalar sum of the transverse missing momentum and the lepton transverse momentum, called L{sub T}. The dominating Standard Model backgrounds in this phase-space are tt+jets and W+jets production. A data-driven method is used to estimate the background in the search regions. All backgrounds except for QCD in the (high ΔΦ(W,l)) signal regions are predicted by from the number of events in the low ΔΦ(W,l) region, with transfer factors determined also from data, while for the multi-jet events a fake-lepton enriched side-band is used. We conclude by showing predictions and final results from data corresponding to 2.1 fb{sup -1} integrated luminosity recorded with the CMS detector during the LHC Run2 in 2015.

  16. Simulation of neutron background for DINO experiment

    International Nuclear Information System (INIS)

    Meghna, K.K.; Bhattacharjee, Pijushpani; Bhattacharya, Satyaki

    2017-01-01

    Various cosmological observations such as rotation curve of galaxies, gravitational lensing etc. establish the existence of a non-luminous matter known as Dark Matter which constitutes about 27% of the matter content of the universe. Despite the evidence for the existence of dark matter, its constituents are still unknown. In underground laboratories, neutrons can be generated mainly by spontaneous fission of U and radiogenic processes, such as by U / Th (α;n) reactions on the rock materials and by cosmogenic processes, such as interaction of cosmic ray muons with rock and shielding materials. We have estimated the flux of both the cosmogenic and the radiogenic neutrons for Jaduguda laboratory facility

  17. Solar Tower Experiments for Radiometric Calibration and Validation of Infrared Imaging Assets and Analysis Tools for Entry Aero-Heating Measurements

    Science.gov (United States)

    Splinter, Scott C.; Daryabeigi, Kamran; Horvath, Thomas J.; Mercer, David C.; Ghanbari, Cheryl M.; Ross, Martin N.; Tietjen, Alan; Schwartz, Richard J.

    2008-01-01

    The NASA Engineering and Safety Center sponsored Hypersonic Thermodynamic Infrared Measurements assessment team has a task to perform radiometric calibration and validation of land-based and airborne infrared imaging assets and tools for remote thermographic imaging. The IR assets and tools will be used for thermographic imaging of the Space Shuttle Orbiter during entry aero-heating to provide flight boundary layer transition thermography data that could be utilized for calibration and validation of empirical and theoretical aero-heating tools. A series of tests at the Sandia National Laboratories National Solar Thermal Test Facility were designed for this task where reflected solar radiation from a field of heliostats was used to heat a 4 foot by 4 foot test panel consisting of LI 900 ceramic tiles located on top of the 200 foot tall Solar Tower. The test panel provided an Orbiter-like entry temperature for the purposes of radiometric calibration and validation. The Solar Tower provided an ideal test bed for this series of radiometric calibration and validation tests because it had the potential to rapidly heat the large test panel to spatially uniform and non-uniform elevated temperatures. Also, the unsheltered-open-air environment of the Solar Tower was conducive to obtaining unobstructed radiometric data by land-based and airborne IR imaging assets. Various thermocouples installed on the test panel and an infrared imager located in close proximity to the test panel were used to obtain surface temperature measurements for evaluation and calibration of the radiometric data from the infrared imaging assets. The overall test environment, test article, test approach, and typical test results are discussed.

  18. Far infrared photoconductors

    International Nuclear Information System (INIS)

    Leotin, J.; Meny, C.

    1990-01-01

    This paper presents the development of far infrared photoconductors for the focal plane of a spaceborne instrument named SAFIRE. SAFIRE (Spectroscopy of the Atmosphere using Far-Infrared Emission) belongs to the EOS program (Earth Observing System) and is now in the definition phase. It is a joint effort by scientists from the United States, Great Britain, Italy and France for a new generation of atmosphere sensor. The overall goal of the SAFIRE experiment is to improve the understanding of the ozone distribution in the middle atmosphere by conducting global scale measurements of the important chemical, radiative and dynamical processes which influence its changes. This will be accomplished by the measurement of the far infrared thermal limb emission in seven spectral channels covering the range 80 to 400 cm -1 with a maximum resolution of 0.004 cm -1 . For example key gases like OH, O, HO 2 , N 2 O 5 will be probed for the first time. Achievement of the required detector sensitivity in the far-infrared imposes the choice of photoconductive detectors operating at liquid helium temperatures. Germanium doped with gallium is selected for six channels whereas germanium doped with beryllium is suitable for the N 2 O 5 channel. Both photoconductors Ge:Ga and Ge:Be benefit from a well established material technology. A better wavelength coverage of channel 1 is achieved by applying a small uniaxial stress of the order of 0.1 GPa on the Ge:Ga photoconductors. The channel 6B wavelength coverage could be improved by using zinc-doped-germanium (Ge:Zn) or, much better, by using a Blocked Impurity band silicon detector doped with antimony (BIB Si:Sb). The later is developed as an optional basis

  19. Infrared small target detection with kernel Fukunaga Koontz transform

    Science.gov (United States)

    Liu, Rui-ming; Liu, Er-qi; Yang, Jie; Zhang, Tian-hao; Wang, Fang-lin

    2007-09-01

    The Fukunaga-Koontz transform (FKT) has been proposed for many years. It can be used to solve two-pattern classification problems successfully. However, there are few researchers who have definitely extended FKT to kernel FKT (KFKT). In this paper, we first complete this task. Then a method based on KFKT is developed to detect infrared small targets. KFKT is a supervised learning algorithm. How to construct training sets is very important. For automatically detecting targets, the synthetic target images and real background images are used to train KFKT. Because KFKT can represent the higher order statistical properties of images, we expect better detection performance of KFKT than that of FKT. The well-devised experiments verify that KFKT outperforms FKT in detecting infrared small targets.

  20. Extragalactic background light measurements and applications.

    Science.gov (United States)

    Cooray, Asantha

    2016-03-01

    This review covers the measurements related to the extragalactic background light intensity from γ-rays to radio in the electromagnetic spectrum over 20 decades in wavelength. The cosmic microwave background (CMB) remains the best measured spectrum with an accuracy better than 1%. The measurements related to the cosmic optical background (COB), centred at 1 μm, are impacted by the large zodiacal light associated with interplanetary dust in the inner Solar System. The best measurements of COB come from an indirect technique involving γ-ray spectra of bright blazars with an absorption feature resulting from pair-production off of COB photons. The cosmic infrared background (CIB) peaking at around 100 μm established an energetically important background with an intensity comparable to the optical background. This discovery paved the way for large aperture far-infrared and sub-millimetre observations resulting in the discovery of dusty, starbursting galaxies. Their role in galaxy formation and evolution remains an active area of research in modern-day astrophysics. The extreme UV (EUV) background remains mostly unexplored and will be a challenge to measure due to the high Galactic background and absorption of extragalactic photons by the intergalactic medium at these EUV/soft X-ray energies. We also summarize our understanding of the spatial anisotropies and angular power spectra of intensity fluctuations. We motivate a precise direct measurement of the COB between 0.1 and 5 μm using a small aperture telescope observing either from the outer Solar System, at distances of 5 AU or more, or out of the ecliptic plane. Other future applications include improving our understanding of the background at TeV energies and spectral distortions of CMB and CIB.

  1. Background music and cognitive performance.

    Science.gov (United States)

    Angel, Leslie A; Polzella, Donald J; Elvers, Greg C

    2010-06-01

    The present experiment employed standardized test batteries to assess the effects of fast-tempo music on cognitive performance among 56 male and female university students. A linguistic processing task and a spatial processing task were selected from the Criterion Task Set developed to assess verbal and nonverbal performance. Ten excerpts from Mozart's music matched for tempo were selected. Background music increased the speed of spatial processing and the accuracy of linguistic processing. The findings suggest that background music can have predictable effects on cognitive performance.

  2. Distortion of the microwave background by dust

    International Nuclear Information System (INIS)

    Rowan-Robinson, M.

    1981-01-01

    The Woody and Richards distortion of the microwave background has a natural explanation within the framework of the isothermal density fluctuation picture. A pregalactic generation of ''stars'' makes light and metals. The latter are able to condense into dust grains at a redshift approximately 150-225, which then absorb the starlight and reradiate it in the infrared. At the present epoch we see this emission redshifted into the millimetre range of the spectrum

  3. Optical characterization of semiconductors infrared, Raman, and photoluminescence spectroscopy

    CERN Document Server

    Perkowitz, Sidney

    1993-01-01

    This is the first book to explain, illustrate, and compare the most widely used methods in optics: photoluminescence, infrared spectroscopy, and Raman scattering. Written with non-experts in mind, the book develops the background needed to understand the why and how of each technique, but does not require special knowledge of semiconductors or optics. Each method is illustrated with numerous case studies. Practical information drawn from the authors experience is given to help establish optical facilities, including commercial sources for equipment, and experimental details. For industrial sci

  4. Infrared small target detection technology based on OpenCV

    Science.gov (United States)

    Liu, Lei; Huang, Zhijian

    2013-09-01

    Accurate and fast detection of infrared (IR) dim target has very important meaning for infrared precise guidance, early warning, video surveillance, etc. In this paper, some basic principles and the implementing flow charts of a series of algorithms for target detection are described. These algorithms are traditional two-frame difference method, improved three-frame difference method, background estimate and frame difference fusion method, and building background with neighborhood mean method. On the foundation of above works, an infrared target detection software platform which is developed by OpenCV and MFC is introduced. Three kinds of tracking algorithms are integrated in this software. In order to explain the software clearly, the framework and the function are described in this paper. At last, the experiments are performed for some real-life IR images. The whole algorithm implementing processes and results are analyzed, and those algorithms for detection targets are evaluated from the two aspects of subjective and objective. The results prove that the proposed method has satisfying detection effectiveness and robustness. Meanwhile, it has high detection efficiency and can be used for real-time detection.

  5. Texture orientation-based algorithm for detecting infrared maritime targets.

    Science.gov (United States)

    Wang, Bin; Dong, Lili; Zhao, Ming; Wu, Houde; Xu, Wenhai

    2015-05-20

    Infrared maritime target detection is a key technology for maritime target searching systems. However, in infrared maritime images (IMIs) taken under complicated sea conditions, background clutters, such as ocean waves, clouds or sea fog, usually have high intensity that can easily overwhelm the brightness of real targets, which is difficult for traditional target detection algorithms to deal with. To mitigate this problem, this paper proposes a novel target detection algorithm based on texture orientation. This algorithm first extracts suspected targets by analyzing the intersubband correlation between horizontal and vertical wavelet subbands of the original IMI on the first scale. Then the self-adaptive wavelet threshold denoising and local singularity analysis of the original IMI is combined to remove false alarms further. Experiments show that compared with traditional algorithms, this algorithm can suppress background clutter much better and realize better single-frame detection for infrared maritime targets. Besides, in order to guarantee accurate target extraction further, the pipeline-filtering algorithm is adopted to eliminate residual false alarms. The high practical value and applicability of this proposed strategy is backed strongly by experimental data acquired under different environmental conditions.

  6. Study on general design of dual-DMD based infrared two-band scene simulation system

    Science.gov (United States)

    Pan, Yue; Qiao, Yang; Xu, Xi-ping

    2017-02-01

    Mid-wave infrared(MWIR) and long-wave infrared(LWIR) two-band scene simulation system is a kind of testing equipment that used for infrared two-band imaging seeker. Not only it would be qualified for working waveband, but also realize the essence requests that infrared radiation characteristics should correspond to the real scene. Past single-digital micromirror device (DMD) based infrared scene simulation system does not take the huge difference between targets and background radiation into account, and it cannot realize the separated modulation to two-band light beam. Consequently, single-DMD based infrared scene simulation system cannot accurately express the thermal scene model that upper-computer built, and it is not that practical. To solve the problem, we design a dual-DMD based, dual-channel, co-aperture, compact-structure infrared two-band scene simulation system. The operating principle of the system is introduced in detail, and energy transfer process of the hardware-in-the-loop simulation experiment is analyzed as well. Also, it builds the equation about the signal-to-noise ratio of infrared detector in the seeker, directing the system overall design. The general design scheme of system is given, including the creation of infrared scene model, overall control, optical-mechanical structure design and image registration. By analyzing and comparing the past designs, we discuss the arrangement of optical engine framework in the system. According to the main content of working principle and overall design, we summarize each key techniques in the system.

  7. Neutron background estimates in GESA

    Directory of Open Access Journals (Sweden)

    Fernandes A.C.

    2014-01-01

    Full Text Available The SIMPLE project looks for nuclear recoil events generated by rare dark matter scattering interactions. Nuclear recoils are also produced by more prevalent cosmogenic neutron interactions. While the rock overburden shields against (μ,n neutrons to below 10−8 cm−2 s−1, it itself contributes via radio-impurities. Additional shielding of these is similar, both suppressing and contributing neutrons. We report on the Monte Carlo (MCNP estimation of the on-detector neutron backgrounds for the SIMPLE experiment located in the GESA facility of the Laboratoire Souterrain à Bas Bruit, and its use in defining additional shielding for measurements which have led to a reduction in the extrinsic neutron background to ∼ 5 × 10−3 evts/kgd. The calculated event rate induced by the neutron background is ∼ 0,3 evts/kgd, with a dominant contribution from the detector container.

  8. Effects of ionizing radiation on cryogenic infrared detectors

    Science.gov (United States)

    Moseley, S. H.; Silverberg, R. F.; Lakew, B.

    1989-01-01

    The Diffuse Infrared Background Experiment (DIRBE) is one of three experiments to be carried aboard the Cosmic Background Explorer (COBE) satellite scheduled to be launched by NASA on a Delta rocket in 1989. The DIRBE is a cryogenic absolute photometer operating in a liquid helium dewar at 1.5 K. Photometric stability is a principal requirement for achieving the scientific objectives of this experiment. The Infrared Astronomy Satellite (IRAS), launched in 1983, which used detectors similar to those in DIRBE, revealed substantial changes in detector responsivity following exposure to ionizing radiation encountered on passage through the South Atlantic Anomaly (SAA). Since the COBE will use the same 900 Km sun-synchronous orbit as IRAS, ionizing radiation-induced performance changes in the detectors were a major concern. Here, ionizing radiation tests carried out on all the DIRBE photodetectors are reported. Responsivity changes following exposure to gamma rays, protons, and alpha particle are discussed. The detector performance was monitored following a simulated entire mission life dose. In addition, the response of the detectors to individual particle interactions was measured. The InSb photovoltaic detectors and the Blocked Impurity Band (BIB) detectors revealed no significant change in responsivity following radiation exposure. The Ge:Ga detectors show large effects which were greatly reduced by proper thermal annealing.

  9. An infrared view of high Tc superconductors

    International Nuclear Information System (INIS)

    Tanner, D.B.; Timusk, T.; McMaster Univ., Hamilton, ON

    1989-01-01

    Studies of the infrared properties of the high T c superconductors are reviewed, with particular emphasis on attempts to determine the energy gap by far infrared spectroscopy and on the properties of the strong absorption that occurs in the mid infrared. The authors argue that this mid-infrared absorption is a direct particle-hole excitation rather than a Holstein emission process. In addition, they conclude that although the energy gap is not easily observed, several recent experiments place it in the weak to moderate strong coupling range

  10. Looking for Cosmic Neutrino Background

    Directory of Open Access Journals (Sweden)

    Chiaki eYanagisawa

    2014-06-01

    Full Text Available Since the discovery of neutrino oscillation in atmospheric neutrinos by the Super-Kamiokande experiment in 1998, study of neutrinos has been one of exciting fields in high-energy physics. All the mixing angles were measured. Quests for 1 measurements of the remaining parameters, the lightest neutrino mass, the CP violating phase(s, and the sign of mass splitting between the mass eigenstates m3 and m1, and 2 better measurements to determine whether the mixing angle theta23 is less than pi/4, are in progress in a well-controlled manner. Determining the nature of neutrinos, whether they are Dirac or Majorana particles is also in progress with continuous improvement. On the other hand, although the ideas of detecting cosmic neutrino background have been discussed since 1960s, there has not been a serious concerted effort to achieve this goal. One of the reasons is that it is extremely difficult to detect such low energy neutrinos from the Big Bang. While there has been tremendous accumulation of information on Cosmic Microwave Background since its discovery in 1965, there is no direct evidence for Cosmic Neutrino Background. The importance of detecting Cosmic Neutrino Background is that, although detailed studies of Big Bang Nucleosynthesis and Cosmic Microwave Background give information of the early Universe at ~a few minutes old and ~300 k years old, respectively, observation of Cosmic Neutrino Background allows us to study the early Universe at $sim$ 1 sec old. This article reviews progress made in the past 50 years on detection methods of Cosmic Neutrino Background.

  11. Caregivers' experience of the decision-making process for placing a person with dementia into a nursing home: comparing caregivers from Chinese ethnic minority with those from English-speaking backgrounds.

    Science.gov (United States)

    Caldwell, Lauren; Low, Lee-Fay; Brodaty, Henry

    2014-03-01

    The experience of care transitions for people with dementia from ethnic minority groups has been poorly researched. Few studies have examined the decision to put someone on a waiting list for a nursing home and then actually accept a place. Many nursing homes have long waiting lists, but sometimes offers of a place are declined. Our aims were to investigate the decision-making process for placing a person with dementia on a waiting list for a nursing home, why offers of a place are accepted or declined, and the influence of cultural factors, comparing caregivers from Chinese and English-speaking backgrounds. Semi-structured interviews with 27 caregivers of people with dementia on waiting lists or living in nursing homes (20 Chinese background and seven English-speaking background) were conducted, with thematic analysis of factors affecting caregivers' decision-making. Caregivers were at different stages of decision-making when they applied for a waiting list - some were ready for placement, others applied "just in case," and for some there was no waiting time because of an urgent need for placement. Caregivers' decisions were influenced by their emotions and expectations of nursing homes. The decision-making process was similar for both cultural groups, but Chinese caregivers spoke more about their sense of duty, the need for a Chinese specific facility, and declining a place because of family disagreement. Understanding cultural issues, including stereotypes and concerns about nursing homes, and providing better information about admission processes may help caregivers by allaying their anxiety about nursing home placement.

  12. Cosmic microwave background radiation

    International Nuclear Information System (INIS)

    Wilson, R.W.

    1979-01-01

    The 20-ft horn-reflector antenna at Bell Laboratories is discussed in detail with emphasis on the 7.35 cm radiometer. The circumstances leading to the detection of the cosmic microwave background radiation are explored

  13. History of Space-Based Infrared Astronomy and the Air Force Infrared Celestial Backgrounds Program

    Science.gov (United States)

    2008-04-18

    previous work by ASE in the classified domain. The Air Force was receptive to providing support to place a small aperture (1 cm²) Geiger counter aboard...1970). On July 4, 1969 we loaded up a U-Haul trailer , having put the baby grand piano into storage, and set off for Boston, arriving two days later... movies were shown in the pub, Thursday had evening shopping and, on an occasional Saturday afternoon, amateur Australian rules football. Otherwise

  14. Zambia Country Background Report

    DEFF Research Database (Denmark)

    Hampwaye, Godfrey; Jeppesen, Søren; Kragelund, Peter

    This paper provides background data and general information for the Zambia studies focusing on local food processing sub­‐sector; and the local suppliers to the mines as part of the SAFIC project (Successful African Firms and Institutional Change).......This paper provides background data and general information for the Zambia studies focusing on local food processing sub­‐sector; and the local suppliers to the mines as part of the SAFIC project (Successful African Firms and Institutional Change)....

  15. Edge enhancement and noise suppression for infrared image based on feature analysis

    Science.gov (United States)

    Jiang, Meng

    2018-06-01

    Infrared images are often suffering from background noise, blurred edges, few details and low signal-to-noise ratios. To improve infrared image quality, it is essential to suppress noise and enhance edges simultaneously. To realize it in this paper, we propose a novel algorithm based on feature analysis in shearlet domain. Firstly, as one of multi-scale geometric analysis (MGA), we introduce the theory and superiority of shearlet transform. Secondly, after analyzing the defects of traditional thresholding technique to suppress noise, we propose a novel feature extraction distinguishing image structures from noise well and use it to improve the traditional thresholding technique. Thirdly, with computing the correlations between neighboring shearlet coefficients, the feature attribute maps identifying the weak detail and strong edges are completed to improve the generalized unsharped masking (GUM). At last, experiment results with infrared images captured in different scenes demonstrate that the proposed algorithm suppresses noise efficiently and enhances image edges adaptively.

  16. An experiment to detect apples infested by the peach fruit moth, Carposina sasakii matsumura (Lepidoptera: Carposinidae), using near-infrared spectroscopy

    International Nuclear Information System (INIS)

    Toyoshima, S.; Nakamoto, Y.; Takanashi, M.; Masuda, T.

    2006-01-01

    The potential of near-infrared spectroscopy to detect apples ('Fuji' cultivar) infested by the peach fruit moth, Carposina sasakii, was evaluated using a prevalent NIR device. A calibration equation was developed using both the NIR spectra and injury levels of the infested fruits. The equation predicted the injury levels of fruits using a simple correlation coefficient of 0.8868 and a standard error of prediction of 0.3688. At the level of estimates to discard ca 90% of infested fruits, 90.15% of the infested fruits and 39.24% of the uninfested fruits were excluded from the samples. Although its accuracy was not sufficient, the present NIR device has the potential to identify internally infested fruits

  17. The Visualization of Infrared Radiation Using Thermal Sensitive Foils

    Science.gov (United States)

    Bochnícek, Zdenek

    2013-01-01

    This paper describes a set of demonstration school experiments where infrared radiation is detected using thermal sensitive foils. The possibility of using standard glass lenses for infrared imaging is discussed in detail. It is shown that with optic components made from glass, infrared radiation up to 2.5 µm of wavelength can be detected. The…

  18. Background Registration-Based Adaptive Noise Filtering of LWIR/MWIR Imaging Sensors for UAV Applications

    Directory of Open Access Journals (Sweden)

    Byeong Hak Kim

    2017-12-01

    Full Text Available Unmanned aerial vehicles (UAVs are equipped with optical systems including an infrared (IR camera such as electro-optical IR (EO/IR, target acquisition and designation sights (TADS, or forward looking IR (FLIR. However, images obtained from IR cameras are subject to noise such as dead pixels, lines, and fixed pattern noise. Nonuniformity correction (NUC is a widely employed method to reduce noise in IR images, but it has limitations in removing noise that occurs during operation. Methods have been proposed to overcome the limitations of the NUC method, such as two-point correction (TPC and scene-based NUC (SBNUC. However, these methods still suffer from unfixed pattern noise. In this paper, a background registration-based adaptive noise filtering (BRANF method is proposed to overcome the limitations of conventional methods. The proposed BRANF method utilizes background registration processing and robust principle component analysis (RPCA. In addition, image quality verification methods are proposed that can measure the noise filtering performance quantitatively without ground truth images. Experiments were performed for performance verification with middle wave infrared (MWIR and long wave infrared (LWIR images obtained from practical military optical systems. As a result, it is found that the image quality improvement rate of BRANF is 30% higher than that of conventional NUC.

  19. Background Registration-Based Adaptive Noise Filtering of LWIR/MWIR Imaging Sensors for UAV Applications

    Science.gov (United States)

    Kim, Byeong Hak; Kim, Min Young; Chae, You Seong

    2017-01-01

    Unmanned aerial vehicles (UAVs) are equipped with optical systems including an infrared (IR) camera such as electro-optical IR (EO/IR), target acquisition and designation sights (TADS), or forward looking IR (FLIR). However, images obtained from IR cameras are subject to noise such as dead pixels, lines, and fixed pattern noise. Nonuniformity correction (NUC) is a widely employed method to reduce noise in IR images, but it has limitations in removing noise that occurs during operation. Methods have been proposed to overcome the limitations of the NUC method, such as two-point correction (TPC) and scene-based NUC (SBNUC). However, these methods still suffer from unfixed pattern noise. In this paper, a background registration-based adaptive noise filtering (BRANF) method is proposed to overcome the limitations of conventional methods. The proposed BRANF method utilizes background registration processing and robust principle component analysis (RPCA). In addition, image quality verification methods are proposed that can measure the noise filtering performance quantitatively without ground truth images. Experiments were performed for performance verification with middle wave infrared (MWIR) and long wave infrared (LWIR) images obtained from practical military optical systems. As a result, it is found that the image quality improvement rate of BRANF is 30% higher than that of conventional NUC. PMID:29280970

  20. Background Registration-Based Adaptive Noise Filtering of LWIR/MWIR Imaging Sensors for UAV Applications.

    Science.gov (United States)

    Kim, Byeong Hak; Kim, Min Young; Chae, You Seong

    2017-12-27

    Unmanned aerial vehicles (UAVs) are equipped with optical systems including an infrared (IR) camera such as electro-optical IR (EO/IR), target acquisition and designation sights (TADS), or forward looking IR (FLIR). However, images obtained from IR cameras are subject to noise such as dead pixels, lines, and fixed pattern noise. Nonuniformity correction (NUC) is a widely employed method to reduce noise in IR images, but it has limitations in removing noise that occurs during operation. Methods have been proposed to overcome the limitations of the NUC method, such as two-point correction (TPC) and scene-based NUC (SBNUC). However, these methods still suffer from unfixed pattern noise. In this paper, a background registration-based adaptive noise filtering (BRANF) method is proposed to overcome the limitations of conventional methods. The proposed BRANF method utilizes background registration processing and robust principle component analysis (RPCA). In addition, image quality verification methods are proposed that can measure the noise filtering performance quantitatively without ground truth images. Experiments were performed for performance verification with middle wave infrared (MWIR) and long wave infrared (LWIR) images obtained from practical military optical systems. As a result, it is found that the image quality improvement rate of BRANF is 30% higher than that of conventional NUC.

  1. Polarization of Cosmic Microwave Background

    International Nuclear Information System (INIS)

    Buzzelli, A; Cabella, P; De Gasperis, G; Vittorio, N

    2016-01-01

    In this work we present an extension of the ROMA map-making code for data analysis of Cosmic Microwave Background polarization, with particular attention given to the inflationary polarization B-modes. The new algorithm takes into account a possible cross- correlated noise component among the different detectors of a CMB experiment. We tested the code on the observational data of the BOOMERanG (2003) experiment and we show that we are provided with a better estimate of the power spectra, in particular the error bars of the BB spectrum are smaller up to 20% for low multipoles. We point out the general validity of the new method. A possible future application is the LSPE balloon experiment, devoted to the observation of polarization at large angular scales. (paper)

  2. Executive Summary - Historical background

    International Nuclear Information System (INIS)

    2005-01-01

    matter physics experiments at the High Flux Reactor of The Laue Langevin Institute and the ISIS spallation source at Rutherford-Appleton. Recently, we very actively entered the ICARUS neutrino collaboration and were invited to the PIERRE AUGER collaboration which will search for the highest energies in the Universe. Having close ties with CERN we are very actively engaged in CROSS-GRID, a large computer network project. To better understand the historical background of the INP development, it is necessary to add a few comments on financing of science in Poland. During the 70's and the 80's, research was financed through the so-called Central Research Projects for Science and Technical Development. The advantage of this system was that state-allocated research funds were divided only by a few representatives of the scientific community, which allowed realistic allocation of money to a small number of projects. After 1989 we were able to purchase commercially available equipment, which led to the closure of our large and very experienced electronic workshop. We also considerably reduced our well equipped mechanical shop. During the 90's the reduced state financing of science was accompanied by a newly established Committee of Scientific Research which led to the creation of a system of small research projects. This precluded the development of more ambitious research projects and led to the dispersion of equipment among many smaller laboratories and universities. A large research establishment, such as our Institute, could not develop properly under such conditions. In all, between 1989 and 2004 we reduced our personnel from about 800 to 470 and our infrastructure became seriously undercapitalised. However, with energetic search for research funds, from European rather than national research programs, we hope to improve and modernize our laboratories and their infrastructure in the coming years

  3. The natural radiation background

    International Nuclear Information System (INIS)

    Duggleby, J.C.

    1982-01-01

    The components of the natural background radiation and their variations are described. Cosmic radiation is a major contributor to the external dose to the human body whilst naturally-occurring radionuclides of primordial and cosmogenic origin contribute to both the external and internal doses, with the primordial radionuclides being the major contributor in both cases. Man has continually modified the radiation dose to which he has been subjected. The two traditional methods of measuring background radiation, ionisation chamber measurements and scintillation counting, are looked at and the prospect of using thermoluminescent dosimetry is considered

  4. Effects of background radiation

    International Nuclear Information System (INIS)

    Knox, E.G.; Stewart, A.M.; Gilman, E.A.; Kneale, G.W.

    1987-01-01

    The primary objective of this investigation is to measure the relationship between exposure to different levels of background gamma radiation in different parts of the country, and different Relative Risks for leukaemias and cancers in children. The investigation is linked to an earlier analysis of the effects of prenatal medical x-rays upon leukaemia and cancer risk; the prior hypothesis on which the background-study was based, is derived from the earlier results. In a third analysis, the authors attempted to measure varying potency of medical x-rays delivered at different stages of gestation and the results supply a link between the other two estimates. (author)

  5. The cosmic microwave background

    International Nuclear Information System (INIS)

    Silk, J.

    1991-01-01

    Recent limits on spectral distortions and angular anisotropies in the cosmic microwave background are reviewed. The various backgrounds are described, and the theoretical implications are assessed. Constraints on inflationary cosmology dominated by cold dark matter (CDM) and on open cosmological models dominated by baryonic dark matter (BDM), with, respectively, primordial random phase scale-invariant curvature fluctuations or non-gaussian isocurvature fluctuations are described. More exotic theories are addressed, and I conclude with the 'bottom line': what theories expect experimentalists to be measuring within the next two to three years without having to abandon their most cherished theorists. (orig.)

  6. Beam-gas Background Observations at LHC

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00214737; The ATLAS collaboration; Alici, Andrea; Lazic, Dragoslav-Laza; Alemany Fernandez, Reyes; Alessio, Federico; Bregliozzi, Giuseppe; Burkhardt, Helmut; Corti, Gloria; Guthoff, Moritz; Manousos, Athanasios; Sjoebaek, Kyrre; D'Auria, Saverio

    2017-01-01

    Observations of beam-induced background at LHC during 2015 and 2016 are presented in this paper. The four LHC experiments use the non-colliding bunches present in the physics-filling pattern of the accelerator to trigger on beam-gas interactions. During luminosity production the LHC experiments record the beam-gas interactions using dedicated background monitors. These data are sent to the LHC control system and are used to monitor the background levels at the experiments during accelerator operation. This is a very important measurement, since poor beam-induced background conditions can seriously affect the performance of the detectors. A summary of the evolution of the background levels during 2015 and 2016 is given in these proceedings.

  7. Thermal background noise limitations

    Science.gov (United States)

    Gulkis, S.

    1982-01-01

    Modern detection systems are increasingly limited in sensitivity by the background thermal photons which enter the receiving system. Expressions for the fluctuations of detected thermal radiation are derived. Incoherent and heterodyne detection processes are considered. References to the subject of photon detection statistics are given.

  8. Feldspar, Infrared Stimulated Luminescence

    DEFF Research Database (Denmark)

    Jain, Mayank

    2014-01-01

    This entry primarily concerns the characteristics and the origins of infrared-stimulated luminescence in feldspars.......This entry primarily concerns the characteristics and the origins of infrared-stimulated luminescence in feldspars....

  9. Gravitational lensing effect and polarization of the cosmic microwave background in the PLANCK Experiment and post-planckian projects; Effet de lentilles gravitationnelles et polarisation du fond diffus cosmologique dans le cadre de l'experience PLANCK et de projets post-planckiens

    Energy Technology Data Exchange (ETDEWEB)

    Perotto, Laurence [Universite Paris 7 - Denis Diderot, UFR de Physique, 75205 Paris Cedex 13 (France)

    2006-01-15

    This thesis is motivated by the upcoming high-resolution, high-sensitivity microwave background experiments, which should be sensitive to the CMB polarization and lensing. The first chapter provides a review of the CMB polarization with emphasis on future related experiments. The PLANCK experiment is described in a second chapter, where I develop a fast simulation code of PLANCK time-ordered data optimized to ease elaboration and test of data analysis methods. The two last chapters deal with gravitational lensing of the cosmic background radiation. First, I evaluate the capability of the upcoming experiments mentioned above to measure the power spectrum of Large Scale Structure by means of the extraction of weak lensing. Then I derive their sensitivity to the total neutrino mass, using the suppression of power due to free-streaming of massive neutrinos. Finally, I develop a method to estimate the foreground effects in the gravitational lensing extraction process. This method uses the best linear estimator available in the literature and is validated by numerical simulations that include non-Gaussian CMB lensed maps and extra-galactic radio sources maps. I find that sources emission reduces the sensitivity of future experiments to the weak lensing and leads to an overestimate of the convergence power spectrum. (author)

  10. Gravitational lensing effect and polarization of the cosmic microwave background in the PLANCK Experiment and post-planckian projects; Effet de lentilles gravitationnelles et polarisation du fond diffus cosmologique dans le cadre de l'experience PLANCK et de projets post-planckiens

    Energy Technology Data Exchange (ETDEWEB)

    Perotto, Laurence [Universite Paris 7 - Denis Diderot, UFR de Physique, 75205 Paris Cedex 13 (France)

    2006-01-15

    This thesis is motivated by the upcoming high-resolution, high-sensitivity microwave background experiments, which should be sensitive to the CMB polarization and lensing. The first chapter provides a review of the CMB polarization with emphasis on future related experiments. The PLANCK experiment is described in a second chapter, where I develop a fast simulation code of PLANCK time-ordered data optimized to ease elaboration and test of data analysis methods. The two last chapters deal with gravitational lensing of the cosmic background radiation. First, I evaluate the capability of the upcoming experiments mentioned above to measure the power spectrum of Large Scale Structure by means of the extraction of weak lensing. Then I derive their sensitivity to the total neutrino mass, using the suppression of power due to free-streaming of massive neutrinos. Finally, I develop a method to estimate the foreground effects in the gravitational lensing extraction process. This method uses the best linear estimator available in the literature and is validated by numerical simulations that include non-Gaussian CMB lensed maps and extra-galactic radio sources maps. I find that sources emission reduces the sensitivity of future experiments to the weak lensing and leads to an overestimate of the convergence power spectrum. (author)

  11. Visible-near infrared point spectrometry of drill core samples from Río Tinto, Spain: results from the 2005 Mars Astrobiology Research and Technology Experiment (MARTE) drilling exercise.

    Science.gov (United States)

    Sutter, Brad; Brown, Adrian J; Stoker, Carol R

    2008-10-01

    Sampling of subsurface rock may be required to detect evidence of past biological activity on Mars. The Mars Astrobiology Research and Technology Experiment (MARTE) utilized the Río Tinto region, Spain, as a Mars analog site to test dry drilling technologies specific to Mars that retrieve subsurface rock for biological analysis. This work examines the usefulness of visible-near infrared (VNIR) (450-1000 nm) point spectrometry to characterize ferric iron minerals in core material retrieved during a simulated Mars drilling mission. VNIR spectrometry can indicate the presence of aqueously precipitated ferric iron minerals and, thus, determine whether biological analysis of retrieved rock is warranted. Core spectra obtained during the mission with T1 (893-897 nm) and T2 (644-652 nm) features indicate goethite-dominated samples, while relatively lower wavelength T1 (832-880 nm) features indicate hematite. Hematite/goethite molar ratios varied from 0 to 1.4, and within the 880-898 nm range, T1 features were used to estimate hematite/goethite molar ratios. Post-mission X-ray analysis detected phyllosilicates, which indicates that examining beyond the VNIR (e.g., shortwave infrared, 1000-2500 nm) will enhance the detection of other minerals formed by aqueous processes. Despite the limited spectral range of VNIR point spectrometry utilized in the MARTE Mars drilling simulation project, ferric iron minerals could be identified in retrieved core material, and their distribution served to direct core subsampling for biological analysis.

  12. Infrared Quenched Photoinduced Superconductivity

    Science.gov (United States)

    Federici, J. F.; Chew, D.; Guttierez-Solana, J.; Molina, G.; Savin, W.; Wilber, W.

    1996-03-01

    Persistant photoconductivity (PPC) and photoinduced superconductivity (PISC) in oxygen deficient YBa_2Cu_3O_6+x have received recent attention. It has been suggested that oxygen vacancy defects play an important role in the PISC/PPC mechanism.(J. F. Federici, D. Chew, B. Welker, W. Savin, J. Gutierrez-Solana, and T. Fink, Phys. Rev. B), December 1995 Supported by National Science Foundation In this model, defects trap photogenerated electrons so that electron-hole recombination can not occur thereby allowing photogenerated holes to contribute to the carrier density. Nominally, the photoinduced state is long-lived, persisting for days at low temperature. Experiment results will be presented demonstrating that the photoinduced superconductivity state can be quenched using infrared radiation. Implications for the validity of the PISC/PCC defect model will be discussed.

  13. Extragalactic infrared astronomy

    International Nuclear Information System (INIS)

    Gondhalekar, P.M.

    1985-05-01

    The paper concerns the field of Extragalactic Infrared Astronomy, discussed at the Fourth RAL Workshop on Astronomy and Astrophysics. Fifteen papers were presented on infrared emission from extragalactic objects. Both ground-(and aircraft-) based and IRAS infrared data were reviewed. The topics covered star formation in galaxies, active galactic nuclei and cosmology. (U.K.)

  14. Sources of the Radio Background Considered

    Energy Technology Data Exchange (ETDEWEB)

    Singal, J.; /KIPAC, Menlo Park /Stanford U.; Stawarz, L.; /KIPAC, Menlo Park /Stanford U. /Jagiellonian U., Astron. Observ.; Lawrence, A.; /Edinburgh U., Inst. Astron. /KIPAC, Menlo Park /Stanford U.; Petrosian, V.; /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., Appl. Phys. Dept.

    2011-08-22

    We investigate possible origins of the extragalactic radio background reported by the ARCADE 2 collaboration. The surface brightness of the background is several times higher than that which would result from currently observed radio sources. We consider contributions to the background from diffuse synchrotron emission from clusters and the intergalactic medium, previously unrecognized flux from low surface brightness regions of radio sources, and faint point sources below the flux limit of existing surveys. By examining radio source counts available in the literature, we conclude that most of the radio background is produced by radio point sources that dominate at sub {mu}Jy fluxes. We show that a truly diffuse background produced by elections far from galaxies is ruled out because such energetic electrons would overproduce the observed X-ray/{gamma}-ray background through inverse Compton scattering of the other photon fields. Unrecognized flux from low surface brightness regions of extended radio sources, or moderate flux sources missed entirely by radio source count surveys, cannot explain the bulk of the observed background, but may contribute as much as 10%. We consider both radio supernovae and radio quiet quasars as candidate sources for the background, and show that both fail to produce it at the observed level because of insufficient number of objects and total flux, although radio quiet quasars contribute at the level of at least a few percent. We conclude that the most important population for production of the background is likely ordinary starforming galaxies above redshift 1 characterized by an evolving radio far-infrared correlation, which increases toward the radio loud with redshift.

  15. Aircraft and background noise annoyance effects

    Science.gov (United States)

    Willshire, K. F.

    1984-01-01

    To investigate annoyance of multiple noise sources, two experiments were conducted. The first experiment, which used 48 subjects, was designed to establish annoyance-noise level functions for three community noise sources presented individually: jet aircraft flyovers, air conditioner, and traffic. The second experiment, which used 216 subjects, investigated the effects of background noise on aircraft annoyance as a function of noise level and spectrum shape; and the differences between overall, aircraft, and background noise annoyance. In both experiments, rated annoyance was the dependent measure. Results indicate that the slope of the linear relationship between annoyance and noise level for traffic is significantly different from that of flyover and air conditioner noise and that further research was justified to determine the influence of the two background noises on overall, aircraft, and background noise annoyance (e.g., experiment two). In experiment two, total noise exposure, signal-to-noise ratio, and background source type were found to have effects on all three types of annoyance. Thus, both signal-to-noise ratio, and the background source must be considered when trying to determine community response to combined noise sources.

  16. Observation of galactic far-infrared ray

    International Nuclear Information System (INIS)

    Maihara, Toshinori; Oda, Naoki; Okuda, Haruyuki; Sugiyama, Takuya; Sakai, Kiyomi.

    1978-01-01

    Galactic far-infrared was observed to study the spatial distribution of interstellar dust. Far-infrared is emitted by interstellar dust distributing throughout the galactic plane. The observation of far-infrared is very important to study the overall structure of the galaxy, that is the structure of the galactic arm and gas distribution. The balloon experiment was conducted on May 25, 1978. The detector was a germanium bolometer cooled by liquid helium. The size of the detector is 1.6 mm in diameter. The geometrical factor was 4 x 10 3 cm 2 sr. The result showed that the longitude distribution of far-infrared at 150 μm correlated with H 166 α recombination line. This indicates that the observed far-infrared is emitted by interstellar dust heated by photons of Lyman continuum. (Yoshimori, M.)

  17. Optimisation of a multivariate analysis technique for the $\\mathbf{{t\\bar{t}}}$ background rejection in the search for Higgs boson pair production in $\\mathbf{b\\bar{b}\\tau^+\\tau^-}$ decay channel with the CMS experiment at the LHC

    CERN Document Server

    Giraldi, Angela

    This thesis reports the optimisation of a multivariate analysis technique for the search for Higgs boson pair ($HH$) production. $HH$ production gives an access to the Higgs boson trilinear self-coupling and is sensitive to the presence of physics beyond the Standard Model. Both resonant and nonresonant production mechanisms are investigated exploring events with one Higgs boson decaying into two $b$ quarks and the other decaying into two $\\tau$ leptons ($HH\\rightarrow b\\bar{b}\\tau^+\\tau^{-}$). This process is studied through the examination of the three decay modes of the $\\tau^+\\tau^{-}$ system, with one or two $\\tau$ decaying into hadrons in the final state. The search uses proton-proton collision data collected at $\\sqrt{s}=13$ TeV with the CMS experiment at the CERN LHC, corresponding to an integrated luminosity of 35.9 fb$^{{-}1}$. The main effort has been devoted to design and develop a multivariate technique to separate the signal from the $t\\bar{t}$ background. This technique has been applied for the...

  18. Initial clinical experience with infrared-reflecting skin markers in the positioning of patients treated by conformal radiotherapy for prostate cancer

    International Nuclear Information System (INIS)

    Soete, Guy; Steene, Jan van de; Verellen, Dirk; Vinh-Hung, Vincent; Berge, Dirk van den; Michielsen, Dirk; Keuppens, Frans; Roover, Patricia de; Storme, Guy

    2002-01-01

    Purpose: To evaluate an infrared (IR) marker-based positioning system in patients receiving conformal radiotherapy for prostate cancer. Methods and materials: During 553 treatments, the ability of the IR system to automatically position the isocenter was recorded. Setup errors were measured by means of orthogonal verification films and compared to conventional positioning (using skin drawings and lasers) in 184 treatments. Results: The standard deviation of anteroposterior (AP) and lateral setup errors was significantly reduced with IR marker positioning compared to conventional: 2 vs. 4.8 mm AP (p<0.01) and 1.6 vs. 3.5 mm laterally (p<0.01). Longitudinally, the difference was not significant (3.5 vs. 3.0 mm). Systematic errors were on the average smaller AP and laterally for the IR method: 4.1 vs. 7.8 mm AP (p=0.01) and 3.1 vs. 5.6 mm lateral (p=0.07). Longitudinally, the IR system resulted in somewhat larger systematic errors: 5.0 vs. 3.4 mm for conventional positioning (p=0.03). The use of an off-line correction protocol, based on the average deviation measured over the first four fractions, allowed virtual elimination of systematic errors. Inability of the IR system to correctly locate the markers, leading to an executional failure, occurred in 21% of 553 fractions. Conclusion: IR marker-assisted patient positioning significantly improves setup accuracy along the AP and lateral axes. Executional failures need to be reduced

  19. A dissociative quantum mechanical/molecular mechanical molecular dynamics simulation and infrared experiments reveal characteristics of the strongly hydrolytic arsenic(III).

    Science.gov (United States)

    Canaval, Lorenz R; Lutz, Oliver M D; Weiss, Alexander K H; Huck, Christian W; Hofer, Thomas S

    2014-11-17

    This work presents a hybrid ab initio quantum mechanical/molecular mechanical simulation at the RI-MP2 level of theory investigating the hydrolysis process of arsenic(III), ultimately leading to arsenous acid (H3AsO3). A newly implemented dissociative water model has been applied to treat the interactions in the classical region, which is capable of describing non-neutral water species such as hydroxide and oxonium ions. Three stages of hydrolysis have been observed during the simulation and besides profound dynamical considerations, detailed insights into structural changes and atomic partial charge shifts are presented. In particular, the geometrical properties of H-bonds involved in each of the three proton transfer events and subsequent proton hopping reactions are discussed. A Laguerre tessellation analysis has been employed to estimate the molecular volume of H3AsO3. Estimations of pKa values of the arsenic(III)-aquo-complexes have been obtained at the G4 and CBS-Q//B3 levels of theory using a thermodynamic cycle, whereas rate constants for the final hydrolysis step have been determined via reaction path optimization and transition state theory. Newly recorded Fourier transform infrared (FT-IR) spectroscopy measurements have been compared to power spectra obtained from the simulation data, confirming its quality. The simulation findings, as well as results from computational spectroscopic calculations utilizing the PT2-VSCF methodology, proved valuable for the interpretation of the experimental FT-IR data, elucidating the particularities of the strongly observed IR Raman noncoincidence effect.

  20. Low background aspects of GERDA

    International Nuclear Information System (INIS)

    Simgen, Hardy

    2011-01-01

    The GERDA experiment operates bare Germanium diodes enriched in 76 Ge in an environment of pure liquid argon to search for neutrinoless double beta decay. A very low radioactive background is essential for the success of the experiment. We present here the research done in order to remove radio-impurities coming from the liquid argon, the stainless steel cryostat and the front-end electronics. We found that liquid argon can be purified efficiently from 222 Rn. The main source of 222 Rn in GERDA is the cryostat which emanates about 55 mBq. A thin copper shroud in the center of the cryostat was implemented to prevent radon from approaching the diodes. Gamma ray screening of radio-pure components for front-end electronics resulted in the development of a pre-amplifier with a total activity of less than 1 mBq 228 Th.

  1. Simulation of Experimental Background using FLUKA

    Energy Technology Data Exchange (ETDEWEB)

    Rokni, Sayed

    1999-05-11

    In November 1997, Experiment T423 began acquiring data with the intentions of understanding the energy spectra of high-energy neutrons generated in the interaction of electrons with lead. The following describes a series of FLUKA simulations studying (1) particle yields in the absence of all background; (2) the background caused from scattering in the room; (3) the effects of the thick lead shielding which surrounded the detector; (4) the sources of neutron background created in this lead shielding; and (5) the ratio of the total background to the ideal yield. In each case, particular attention is paid to the neutron yield.

  2. [The study of transpiration influence on plant infrared radiation character].

    Science.gov (United States)

    Ling, Jun; Zhang, Shuan-Qin; Pan, Jia-Liang; Lian, Chang-Chun; Yang, Hui

    2012-07-01

    Studying vegetation infrared radiation character is the base of developing infrared camouflage and concealment technology of ground military target. Accurate fusion of target and background can be achieved by simulating formation mechanism of vegetation infrared radiation character. Leaf transpiration is characteristic physiological mechanism of vegetation and one of the main factors that influence its infrared radiation character. In the present paper, physical model of leaf energy balance is set up. Based on this model the influence of plant transpiration on leaf temperature is analyzed and calculated. The daily periodic variation of transpiration, leaf temperature and infrared radiation character of typical plants such as camphor tree and holly is actually measured with porometer and infrared thermal imaging system. By contrasting plant leaf with dryness leaf, experimental data indicates that plant transpiration can regulate leaf energy balance effectively and control leaf temperature in a reasonable range and suppress deep range variation of leaf infrared radiation character.

  3. Introductory survey for wireless infrared communications

    Directory of Open Access Journals (Sweden)

    Munsif Ali Jatoi

    2014-08-01

    Full Text Available Wireless infrared communications can be defined as the propagation of light waves in free space using infrared radiation whose range is 400–700 nm. This range corresponds to frequencies of hundreds of terahertz, which is high for higher data rate applications. Wireless infrared is applied for higher data rates applications such as wireless computing, wireless video and wireless multimedia communication applications. Introduced by Gfeller, this field has grown with different link configurations, improved transmitter efficiency, increased receiver responsivity and various multiple access techniques for improved quality. Errors are caused because of background light, which causes degradation overall system performance. Error correction techniques are used to remove the errors caused during transmission. This study provides a brief account on field theory used for error correction in wireless infrared systems. The results are produced in terms of bit error rate and signal-to-noise ratio for various bit lengths to show the ability of encoding and decoding algorithms.

  4. Family Background and Entrepreneurship

    DEFF Research Database (Denmark)

    Lindquist, Matthew J.; Sol, Joeri; Van Praag, Mirjam

    Vast amounts of money are currently being spent on policies aimed at promoting entrepreneurship. The success of such policies, however, rests in part on the assumption that individuals are not ‘born entrepreneurs’. In this paper, we assess the importance of family background and neighborhood...... effects as determinants of entrepreneurship. We start by estimating sibling correlations in entrepreneurship. We find that between 20 and 50 percent of the variance in different entrepreneurial outcomes is explained by factors that siblings share. The average is 28 percent. Allowing for differential...... entrepreneurship does play a large role, as do shared genes....

  5. Malaysia; Background Paper

    OpenAIRE

    International Monetary Fund

    1996-01-01

    This Background Paper on Malaysia examines developments and trends in the labor market since the mid-1980s. The paper describes the changes in the employment structure and the labor force. It reviews wages and productivity trends and their effects on unit labor cost. The paper highlights that Malaysia’s rapid growth, sustained since 1987, has had a major impact on the labor market. The paper outlines the major policy measures to address the labor constraints. It also analyzes Malaysia’s recen...

  6. Analysis of the SIAM Infrared Acquisition System

    Energy Technology Data Exchange (ETDEWEB)

    Varnado, S.G.

    1974-02-01

    This report describes and presents the results of an analysis of the performance of the infrared acquisition system for a Self-Initiated Antiaircraft Missile (SIAM). A description of the optical system is included, and models of target radiant intensity, atmospheric transmission, and background radiance are given. Acquisition probabilities are expressed in terms of the system signal-to-noise ratio. System performance against aircraft and helicopter targets is analyzed, and background discrimination techniques are discussed. 17 refs., 22 figs., 6 tabs.

  7. Wyoming Infrared Observatory's Summer Undergraduate Research Assistantship Program: 10 Years of REU

    Science.gov (United States)

    Canterna, R.; Beck, K.; Hickman, M. A.

    1996-05-01

    The Wyoming Infrared Observatory's Summer Undergraduate Research Assistantship Program (SURAP) will complete its tenth year as an NSF REU site. Using the theme, a tutorial in research, SURAP has provided research experience for over 90 students from all regions of the United States. We will present typical histories of past students to illustrate the impact an REU experience has on the scientific careers of these students. Demographic data will be presented to show the diverse backgrounds of our SURAP students. A short film describing our science ethics seminar will be available for later presentation.

  8. Hydrothermal Synthesis and Characterization of a Metal-Organic Framework by Thermogravimetric Analysis, Powder X-Ray Diffraction, and Infrared Spectroscopy: An Integrative Inorganic Chemistry Experiment

    Science.gov (United States)

    Crane, Johanna L.; Anderson, Kelly E.; Conway, Samantha G.

    2015-01-01

    This advanced undergraduate laboratory experiment involves the synthesis and characterization of a metal-organic framework with microporous channels that are held intact via hydrogen bonding of the coordinated water molecules. The hydrothermal synthesis of Co[subscript 3](BTC)[subscript 2]·12H[subscript 2]O (BTC = 1,3,5-benzene tricarboxylic acid)…

  9. Far-infrared contraband-detection-system development for personnel-search applications

    International Nuclear Information System (INIS)

    Schellenbaum, R.L.

    1982-09-01

    Experiments have been conducted toward the development of an active near-millimeter-wave, far infrared, personnel search system for the detection of contraband. These experiments employed a microwave hybrid tee interferometer/radiometer scanning system and quasi-optical techniques at 3.3-mm wavelength to illuminate and detect the reflection from target objects against a human body background. Clothing and other common concealing materials are transport at this wavelength. Retroreflector arrays, in conjunction with a Gunn diode radiation source, were investigated to provide all-angle illumination and detection of specular reflections from unaligned and irregular-shaped objects. Results indicate that, under highly controlled search conditions, metal objects greater than or equal to 25 cm 2 can be detected in an enclosure lined with retroreflectors. Further development is required to produce a practical personnel search system. The investigation and feasibility of alternate far infrared search techniques are presented. 23 figures, 2 tables

  10. Infrared observations of planetary atmospheres

    International Nuclear Information System (INIS)

    Orton, G.S.; Baines, K.H.; Bergstralh, J.T.

    1988-01-01

    The goal of this research in to obtain infrared data on planetary atmospheres which provide information on several aspects of structure and composition. Observations include direct mission real-time support as well as baseline monitoring preceding mission encounters. Besides providing a broader information context for spacecraft experiment data analysis, observations will provide the quantitative data base required for designing optimum remote sensing sequences and evaluating competing science priorities. In the past year, thermal images of Jupiter and Saturn were made near their oppositions in order to monitor long-term changes in their atmospheres. Infrared images of the Jovian polar stratospheric hot spots were made with IUE observations of auroral emissions. An exploratory 5-micrometer spectrum of Uranus was reduced and accepted for publication. An analysis of time-variability of temperature and cloud properties of the Jovian atomsphere was made. Development of geometric reduction programs for imaging data was initiated for the sun workstation. Near-infrared imaging observations of Jupiter were reduced and a preliminary analysis of cloud properties made. The first images of the full disk of Jupiter with a near-infrared array camera were acquired. Narrow-band (10/cm) images of Jupiter and Saturn were obtained with acousto-optical filters

  11. On the sensitivity of heterodyne detectors in far infrared astronomy

    International Nuclear Information System (INIS)

    Bueren, H.G. van

    1976-01-01

    The signal-to-noise ratio of astronomical heterodyne detection infrared spectrographs is considered, taking into account background, linewidth and seeing effects. A comparison with incoherent detector systems is presented. (author)

  12. The Zugspitze radiative closure experiment for quantifying water vapor absorption over the terrestrial and solar infrared – Part 3: Quantification of the mid- and near-infrared water vapor continuum in the 2500 to 7800 cm−1 spectral range under atmospheric conditions

    Directory of Open Access Journals (Sweden)

    A. Reichert

    2016-09-01

    Full Text Available We present a first quantification of the near-infrared (NIR water vapor continuum absorption from an atmospheric radiative closure experiment carried out at the Zugspitze (47.42° N, 10.98° E; 2964 m a.s.l.. Continuum quantification is achieved via radiative closure using radiometrically calibrated solar Fourier transform infrared (FTIR absorption spectra covering the 2500 to 7800 cm−1 spectral range. The dry atmospheric conditions at the Zugspitze site (IWV 1.4 to 3.3 mm enable continuum quantification even within water vapor absorption bands, while upper limits for continuum absorption can be provided in the centers of window regions. Throughout 75 % of the 2500 to 7800 cm−1 spectral range, the Zugspitze results agree within our estimated uncertainty with the widely used MT_CKD 2.5.2 model (Mlawer et al., 2012. In the wings of water vapor absorption bands, our measurements indicate about 2–5 times stronger continuum absorption than MT_CKD, namely in the 2800 to 3000 cm−1 and 4100 to 4200 cm−1 spectral ranges. The measurements are consistent with the laboratory measurements of Mondelain et al. (2015, which rely on cavity ring-down spectroscopy (CDRS, and the calorimetric–interferometric measurements of Bicknell et al. (2006. Compared to the recent FTIR laboratory studies of Ptashnik et al. (2012, 2013, our measurements are consistent within the estimated errors throughout most of the spectral range. However, in the wings of water vapor absorption bands our measurements indicate typically 2–3 times weaker continuum absorption under atmospheric conditions, namely in the 3200 to 3400, 4050 to 4200, and 6950 to 7050 cm−1 spectral regions.

  13. Exploring the Large Scale Anisotropy in the Cosmic Microwave Background Radiation at 170 GHz

    Science.gov (United States)

    Ganga, Kenneth Matthew

    1994-01-01

    In this thesis, data from the Far Infra-Red Survey (FIRS), a balloon-borne experiment designed to measure the large scale anisotropy in the cosmic microwave background radiation, are analyzed. The FIRS operates in four frequency bands at 170, 280, 480, and 670 GHz, using an approximately Gaussian beam with a 3.8 deg full-width-at-half-maximum. A cross-correlation with the COBE/DMR first-year maps yields significant results, confirming the DMR detection of anisotropy in the cosmic microwave background radiation. Analysis of the FIRS data alone sets bounds on the amplitude of anisotropy under the assumption that the fluctuations are described by a Harrison-Peebles-Zel'dovich spectrum and further analysis sets limits on the index of the primordial density fluctuations for an Einstein-DeSitter universe. Galactic dust emission is discussed and limits are set on the magnitude of possible systematic errors in the measurement.

  14. Backgrounded but not peripheral

    DEFF Research Database (Denmark)

    Hovmark, Henrik

    2013-01-01

    .e. the schema enters into apparently contradictory constructions of the informants’ local home-base and, possibly, of their identity (cf. Hovmark, 2010). Second, I discuss the status and role of the specific linguistic category in question, i.e. the directional adverbs. On the one hand we claim that the DDAs......In this paper I pay a closer look at the use of the CENTRE-PERIPHERY schema in context. I address two specific issues: first, I show how the CENTRE-PERIPHERY schema, encoded in the DDAs, enters into discourses that conceptualize and characterize a local community as both CENTRE and PERIPHERY, i......; furthermore, the DDAs are backgrounded in discourse. Is it reasonable to claim, rather boldly, that “the informants express their identity in the use of the directional adverb ud ‘out’ etc.”? In the course of this article, however, I suggest that the DDAs in question do contribute to the socio...

  15. OCRWM Backgrounder, January 1987

    International Nuclear Information System (INIS)

    1987-01-01

    The Nuclear Waste Policy Act of 1982 (NWPA) assigns to the US Department of Energy (DOE) responsibility for developing a system to safely and economically transport spent nuclear fuel and high-level radioactive waste from various storage sites to geologic repositories or other facilities that constitute elements of the waste management program. This transportation system will evolve from technologies and capabilities already developed. Shipments of spent fuel to a monitored retrievable storage (MRS) facility could begin as early as 1996 if Congress authorizes its construction. Shipments of spent fuel to a geologic repository are scheduled to begin in 1998. The backgrounder provides an overview of DOE's cask development program. Transportation casks are a major element in the DOE nuclear waste transportation system because they are the primary protection against any potential radiation exposure to the public and transportation workers in the event an accident occurs

  16. Monitored background radiometer

    International Nuclear Information System (INIS)

    Ruel, C.

    1988-01-01

    A monitored background radiometer is described comprising: a thermally conductive housing; low conductivity support means mounted on the housing; a sensing plate mounted on the low conductivity support means and spaced from the housing so as to be thermally insulated from the housing and having an outwardly facing first surface; the sensing plate being disposed relative to the housing to receive direct electromagnetic radiation from sources exterior to the radiometer upon the first surface only; means for controllably heating the sensing plate; first temperature sensitive means to measure the temperature of the housing; and second temperature sensitive means to measure the temperature of the sensing plate, so that the heat flux at the sensing plate may be determined from the temperatures of the housing and sensing plate after calibration of the radiometer by measuring the temperatures of the housing and sensing plate while controllably heating the sensing plate

  17. FAR-INFRARED EXTINCTION MAPPING OF INFRARED DARK CLOUDS

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Wanggi [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States); Tan, Jonathan C. [Departments of Astronomy and Physics, University of Florida, Gainesville, FL 32611 (United States)

    2014-01-10

    Progress in understanding star formation requires detailed observational constraints on the initial conditions, i.e., dense clumps and cores in giant molecular clouds that are on the verge of gravitational instability. Such structures have been studied by their extinction of near-infrared and, more recently, mid-infrared (MIR) background light. It has been somewhat more of a surprise to find that there are regions that appear as dark shadows at far-infrared (FIR) wavelengths as long as ∼100 μm! Here we develop analysis methods of FIR images from Spitzer-MIPS and Herschel-PACS that allow quantitative measurements of cloud mass surface density, Σ. The method builds on that developed for MIR extinction mapping by Butler and Tan, in particular involving a search for independently saturated, i.e., very opaque, regions that allow measurement of the foreground intensity. We focus on three massive starless core/clumps in the Infrared Dark Cloud (IRDC) G028.37+00.07, deriving mass surface density maps from 3.5 to 70 μm. A by-product of this analysis is the measurement of the spectral energy distribution of the diffuse foreground emission. The lower opacity at 70 μm allows us to probe to higher Σ values, up to ∼1 g cm{sup –2} in the densest parts of the core/clumps. Comparison of the Σ maps at different wavelengths constrains the shape of the MIR-FIR dust opacity law in IRDCs. We find that it is most consistent with the thick ice mantle models of Ossenkopf and Henning. There is tentative evidence for grain ice mantle growth as one goes from lower to higher Σ regions.

  18. FAR-INFRARED EXTINCTION MAPPING OF INFRARED DARK CLOUDS

    International Nuclear Information System (INIS)

    Lim, Wanggi; Tan, Jonathan C.

    2014-01-01

    Progress in understanding star formation requires detailed observational constraints on the initial conditions, i.e., dense clumps and cores in giant molecular clouds that are on the verge of gravitational instability. Such structures have been studied by their extinction of near-infrared and, more recently, mid-infrared (MIR) background light. It has been somewhat more of a surprise to find that there are regions that appear as dark shadows at far-infrared (FIR) wavelengths as long as ∼100 μm! Here we develop analysis methods of FIR images from Spitzer-MIPS and Herschel-PACS that allow quantitative measurements of cloud mass surface density, Σ. The method builds on that developed for MIR extinction mapping by Butler and Tan, in particular involving a search for independently saturated, i.e., very opaque, regions that allow measurement of the foreground intensity. We focus on three massive starless core/clumps in the Infrared Dark Cloud (IRDC) G028.37+00.07, deriving mass surface density maps from 3.5 to 70 μm. A by-product of this analysis is the measurement of the spectral energy distribution of the diffuse foreground emission. The lower opacity at 70 μm allows us to probe to higher Σ values, up to ∼1 g cm –2 in the densest parts of the core/clumps. Comparison of the Σ maps at different wavelengths constrains the shape of the MIR-FIR dust opacity law in IRDCs. We find that it is most consistent with the thick ice mantle models of Ossenkopf and Henning. There is tentative evidence for grain ice mantle growth as one goes from lower to higher Σ regions

  19. Introduction to experimental infrared spectroscopy fundamentals and practical methods

    CERN Document Server

    Tasumi, Mitsuo; Ochiai, Shukichi

    2014-01-01

    Infrared spectroscopy is generally understood to mean the science of spectra relating to infrared radiation, namely electromagnetic waves, in the wavelength region occurring intermediately between visible light and microwaves. Measurements of infrared spectra have been providing useful information, for a variety of scientific research and industrial studies, for over half a century; this is set to continue in the foreseeable future. Introduction to Experimental Infrared Spectroscopy is intended to be a handy guide for those who have no, or limited, experience in infrared spectroscopi

  20. Infrared microscope inspection apparatus

    Science.gov (United States)

    Forman, Steven E.; Caunt, James W.

    1985-02-26

    Apparatus and system for inspecting infrared transparents, such as an array of photovoltaic modules containing silicon solar cells, includes an infrared microscope, at least three sources of infrared light placed around and having their axes intersect the center of the object field and means for sending the reflected light through the microscope. The apparatus is adapted to be mounted on an X-Y translator positioned adjacent the object surface.

  1. Far infrared supplement: Catalog of infrared observations, second edition

    International Nuclear Information System (INIS)

    Gezari, D.Y.; Schmitz, M.; Mead, J.M.

    1988-08-01

    The Far Infrared Supplement: Catalog of Infrared Observations summarizes all infrared astronomical observations at far infrared wavelengths (5 to 1000 microns) published in the scientific literature from 1965 through 1986. The Supplement list contain 25 percent of the observations in the full Catalog of Infrared Observations (CIO), and essentially eliminates most visible stars from the listings. The Supplement is thus more compact than the main catalog, and is intended for easy reference during astronomical observations. The Far Infrared Supplement (2nd Edition) includes the Index of Infrared Source Positions and the Bibliography of Infrared Astronomy for the subset of far infrared observations listed

  2. Mid-Infrared Lasers

    Data.gov (United States)

    National Aeronautics and Space Administration — Mid infrared solid state lasers for Differential Absorption Lidar (DIAL) systems required for understanding atmospheric chemistry are not available. This program...

  3. Hanford Site background: Part 1, Soil background for nonradioactive analytes

    International Nuclear Information System (INIS)

    1993-04-01

    Volume two contains the following appendices: Description of soil sampling sites; sampling narrative; raw data soil background; background data analysis; sitewide background soil sampling plan; and use of soil background data for the detection of contamination at waste management unit on the Hanford Site

  4. Semiconductor optoelectronic infrared spectroscopy

    International Nuclear Information System (INIS)

    Hollingworth, A.R.

    2001-08-01

    We use spectroscopy to study infrared optoelectronic inter and intraband semiconductor carrier dynamics. The overall aim of this thesis was to study both III-V and Pb chalcogenide material systems in order to show their future potential use in infrared emitters. The effects of bandstructure engineering have been studied in the output characteristics of mid-IR III-V laser diodes to show which processes (defects, radiative, Auger and phonon) dominate and whether non-radiative processes can be suppressed. A new three-beam pump probe experiment was used to investigate interband recombination directly in passive materials. Experiments on PbSe and theory for non-parabolic near-mirror bands and non-degenerate statistics were in good agreement. Comparisons with HgCdTe showed a reduction in the Auger coefficient of 1-2 orders of magnitude in the PbSe. Using Landau confinement to model spatial confinement in quantum dots (QDs) 'phonon bottlenecking' was studied. The results obtained from pump probe and cyclotron resonance saturation measurements showed a clear suppression in the cooling of carriers when Landau level separation was not resonant with LO phonon energy. When a bulk laser diode was placed in a magnetic field to produce a quasi quantum wire device the resulting enhanced differential gain and reduced Auger recombination lowered I th by 30%. This result showed many peaks in the light output which occurred when the LO phonon energy was a multiple of the Landau level separation. This showed for the first time evidence of the phonon bottleneck in a working laser device. A new technique called time resolved optically detected cyclotron resonance, was used as a precursor to finding the carrier dynamics within a spatially confined quantum dot. By moving to the case of a spatial QD using an optically detected intraband resonance it was possible to measure the energy separation interband levels and conduction and valence sublevels within the dot simultaneously. Furthermore

  5. Summary of professional background

    International Nuclear Information System (INIS)

    Tolstykh, V.

    1990-01-01

    The main objectives of IAEA-IRS activity are to prevent repetition of unusual events in other NPPs, at other locations and to enhance the capability of the nuclear community to improve nuclear safety. This paper outlines the experience of international expertise in the analysis of data collection on unusual events in NPPs. Examples illustrate IAEA-IRS analysis activity in practice - trends and patterns identified by a human expert. The importance of the use of modern techniques simulating and supporting human decision-making processes for analysis of IRS information is briefly discussed

  6. Detection of WIMPs in the Edelweiss experiment. Study of the radioactive background noise and measurements with bolometers; Recherche des wimp's du halo galactique dans l'experience edelweiss: etude du bas bruit radioactif et mesures a l'aide de bolometres a double detection ionisation/chaleur

    Energy Technology Data Exchange (ETDEWEB)

    Miramonti, L. [CEA/Saclay, Dept. d' Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l' Instrumentation Associee (DAPNIA), 91 - Gif-sur-Yvette (France)]|[Paris-11 Univ., 91 - Orsay (France)

    1999-11-01

    This thesis is dedicated to the detection of black matter in the form of WIMPs (weakly interacting massive particle). The characteristics of the interaction of WIMPs with matter are recalled. The very low number of expected events (<1 event/day.Kg) implies a radioactive background noise as weak as possible, furthermore the exponential decrease of the interacting rate with increasing energy calls for detectors with very low thresholds. Bolometers present advantages in WIMPs detection: i) very good resolution and very low thresholds, ii) very broad range of materials that can be used as absorber, the only requirements are: a crystal structure, to be a diamagnetic isolator and to have a convenient Debye temperature, iii) the possibility of detecting ionizing or non-ionizing particles, iv) the possibility of identifying the incident particle by measuring both temperature and another parameter such as ionization or scintillation, and v) the possibility of localizing the interaction inside the absorber by detecting ballistic phonons. The problematic of radioactive background noise is presented and the answers to the different sources (cosmic radiation,natural and artificial radioactivity) generating the background noise are examined. The materials used in the building of the detector and cryostat must be carefully chosen, they should be as little radioactive as possible. The test benches used to select materials for the Edelweiss experiment are described. The first measurements concerning the detectors Ge-4 and Ge-7 are presented. (A.C.)

  7. Note on bouncing backgrounds

    Science.gov (United States)

    de Haro, Jaume; Pan, Supriya

    2018-05-01

    The theory of inflation is one of the fundamental and revolutionary developments of modern cosmology that became able to explain many issues of the early Universe in the context of the standard cosmological model (SCM). However, the initial singularity of the Universe, where physics is indefinite, is still obscure in the combined SCM +inflation scenario. An alternative to SCM +inflation without the initial singularity is thus always welcome, and bouncing cosmology is an attempt at that. The current work is thus motivated to investigate the bouncing solutions in modified gravity theories when the background universe is described by the spatially flat Friedmann-Lemaître-Robertson-Walker (FLRW) geometry. We show that the simplest way to obtain the bouncing cosmologies in such spacetime is to consider some kind of Lagrangian whose gravitational sector depends only on the square of the Hubble parameter of the FLRW universe. For these modified Lagrangians, the corresponding Friedmann equation, a constraint in the dynamics of the Universe, depicts a curve in the phase space (H ,ρ ), where H is the Hubble parameter and ρ is the energy density of the Universe. As a consequence, a bouncing cosmology is obtained when this curve is closed and crosses the axis H =0 at least twice, and whose simplest particular example is the ellipse depicting the well-known holonomy corrected Friedmann equation in loop quantum cosmology (LQC). Sometimes, a crucial point in such theories is the appearance of the Ostrogradski instability at the perturbative level; however, fortunately enough, in the present work, as long as the linear level of perturbations is concerned, this instability does not appear, although it may appear at the higher order of perturbations.

  8. Infrared laser induced population transfer and parity selection in (14)NH3: A proof of principle experiment towards detecting parity violation in chiral molecules.

    Science.gov (United States)

    Dietiker, P; Miloglyadov, E; Quack, M; Schneider, A; Seyfang, G

    2015-12-28

    We have set up an experiment for the efficient population transfer by a sequential two photon-absorption and stimulated emission-process in a molecular beam to prepare quantum states of well defined parity and their subsequent sensitive detection. This provides a proof of principle for an experiment which would allow for parity selection and measurement of the time evolution of parity in chiral molecules, resulting in a measurement of the parity violating energy difference ΔpvE between enantiomers of chiral molecules. Here, we present first results on a simple achiral molecule demonstrating efficient population transfer (about 80% on the average for each step) and unperturbed persistence of a selected excited parity level over flight times of about 1.3 ms in the beam. In agreement with model calculations with and without including nuclear hyperfine structure, efficient population transfer can be achieved by a rather simple implementation of the rapid adiabatic passage method of Reuss and coworkers and considering also the stimulated Raman adiabatic passage technique of Bergmann and coworkers as an alternative. The preparation step uses two powerful single mode continuous wave optical parametric oscillators of high frequency stability and accuracy. The detection uses a sensitive resonantly enhanced multiphoton ionization method after free flight lengths of up to 0.8 m in the molecular beam. Using this technique, we were able to also resolve the nuclear hyperfine structure in the rovibrational levels of the ν1 and ν3 fundamentals as well as the 2ν4 overtone of (14)NH3, for which no previous data with hyperfine resolution were available. We present our new results on the quadrupole coupling constants for the ν1, ν3, and 2ν4 levels in the context of previously known data for ν2 and its overtone, as well as ν4, and the ground state. Thus, now, (14)N quadrupole coupling constants for all fundamentals and some overtones of (14)NH3 are known and can be used for

  9. Infrared laser induced population transfer and parity selection in {sup 14}NH{sub 3}: A proof of principle experiment towards detecting parity violation in chiral molecules

    Energy Technology Data Exchange (ETDEWEB)

    Dietiker, P.; Miloglyadov, E.; Quack, M., E-mail: Martin@Quack.ch; Schneider, A.; Seyfang, G. [Physical Chemistry, ETH Zürich, CH-8093 Zürich (Switzerland)

    2015-12-28

    We have set up an experiment for the efficient population transfer by a sequential two photon—absorption and stimulated emission—process in a molecular beam to prepare quantum states of well defined parity and their subsequent sensitive detection. This provides a proof of principle for an experiment which would allow for parity selection and measurement of the time evolution of parity in chiral molecules, resulting in a measurement of the parity violating energy difference Δ{sub pv}E between enantiomers of chiral molecules. Here, we present first results on a simple achiral molecule demonstrating efficient population transfer (about 80% on the average for each step) and unperturbed persistence of a selected excited parity level over flight times of about 1.3 ms in the beam. In agreement with model calculations with and without including nuclear hyperfine structure, efficient population transfer can be achieved by a rather simple implementation of the rapid adiabatic passage method of Reuss and coworkers and considering also the stimulated Raman adiabatic passage technique of Bergmann and coworkers as an alternative. The preparation step uses two powerful single mode continuous wave optical parametric oscillators of high frequency stability and accuracy. The detection uses a sensitive resonantly enhanced multiphoton ionization method after free flight lengths of up to 0.8 m in the molecular beam. Using this technique, we were able to also resolve the nuclear hyperfine structure in the rovibrational levels of the ν{sub 1} and ν{sub 3} fundamentals as well as the 2ν{sub 4} overtone of {sup 14}NH{sub 3}, for which no previous data with hyperfine resolution were available. We present our new results on the quadrupole coupling constants for the ν{sub 1}, ν{sub 3}, and 2ν{sub 4} levels in the context of previously known data for ν{sub 2} and its overtone, as well as ν{sub 4}, and the ground state. Thus, now, {sup 14}N quadrupole coupling constants for all

  10. Infrared spectroscopy by use of synchrotron radiation

    International Nuclear Information System (INIS)

    Nanba, Takao

    1991-01-01

    During five years since the author wrote the paper on the utilization of synchrotron radiation in long wavelength region, it seems to be recognized that in synchrotron radiation, the light from infrared to milli wave can be utilized, and is considerably useful. Recently the research on coherent synchrotron radiation in this region using electron linac has been developed by Tohoku University group, and the high capability of synchrotron radiation as light source is verified. This paper is the report on the infrared spectroscopic research using incoherent synchrotron radiation obtained from the deflection electromagnet part of electron storage rings. Synchrotron radiation is high luminance white light source including from X-ray to micro wave. The example of research that the author carried out at UVSOR is reported, and the perspective in near future is mentioned. Synchrotron radiation as the light source for infrared spectroscopy, the intensity and dimensions of the light source, far infrared region and mid infrared region, far infrared high pressure spectroscopic experiment, and the heightening of luminance of synchrotron radiation as infrared light source are described. (K.I.)

  11. On infrared divergences

    International Nuclear Information System (INIS)

    Parisi, G.

    1979-01-01

    The structure of infrared divergences is studied in superrenormalizable interactions. It is conjectured that there is an extension of the Bogoliubov-Parasiuk-Hepp theorem which copes also with infrared divergences. The consequences of this conjecture on the singularities of the Borel transform in a massless asymptotic free field theory are discussed. The application of these ideas to gauge theories is briefly discussed. (Auth.)

  12. Human body region enhancement method based on Kinect infrared imaging

    Science.gov (United States)

    Yang, Lei; Fan, Yubo; Song, Xiaowei; Cai, Wenjing

    2016-10-01

    To effectively improve the low contrast of human body region in the infrared images, a combing method of several enhancement methods is utilized to enhance the human body region. Firstly, for the infrared images acquired by Kinect, in order to improve the overall contrast of the infrared images, an Optimal Contrast-Tone Mapping (OCTM) method with multi-iterations is applied to balance the contrast of low-luminosity infrared images. Secondly, to enhance the human body region better, a Level Set algorithm is employed to improve the contour edges of human body region. Finally, to further improve the human body region in infrared images, Laplacian Pyramid decomposition is adopted to enhance the contour-improved human body region. Meanwhile, the background area without human body region is processed by bilateral filtering to improve the overall effect. With theoretical analysis and experimental verification, the results show that the proposed method could effectively enhance the human body region of such infrared images.

  13. Infrared monitoring of combustion

    International Nuclear Information System (INIS)

    Bates, S.C.; Morrison, P.W. Jr.; Solomon, P.R.

    1991-01-01

    In this paper, the use of Fourier Transform Infrared (FT-IR) spectroscopy for combustion monitoring is described. A combination of emission, transmission, and reflection FT-IR spectroscopy yields data on the temperature and composition of the gases, surfaces and suspended particles in the combustion environment. Detection sensitivity of such trace exhaust gases as CO, CO 2 , SO 2 , NO x , and unburned hydrocarbons is at the ppm level. Tomographic reconstruction converts line-of-sight measurements into spatially resolved temperature and concentration data. Examples from various combustion processes are used to demonstrate the capabilities of the technique. Industrial measurements are described that have been performed directly in the combustion zone and in the exhaust duct of a large chemical recovery boiler. Other measurements of hot slag show how FT-IR spectroscopy can determine the temperature and optical properties of surfaces. In addition, experiments with water droplets show that transmission FT-IR data yield spectra that characterize particle size and number density

  14. Sparse representation for infrared Dim target detection via a discriminative over-complete dictionary learned online.

    Science.gov (United States)

    Li, Zheng-Zhou; Chen, Jing; Hou, Qian; Fu, Hong-Xia; Dai, Zhen; Jin, Gang; Li, Ru-Zhang; Liu, Chang-Ju

    2014-05-27

    It is difficult for structural over-complete dictionaries such as the Gabor function and discriminative over-complete dictionary, which are learned offline and classified manually, to represent natural images with the goal of ideal sparseness and to enhance the difference between background clutter and target signals. This paper proposes an infrared dim target detection approach based on sparse representation on a discriminative over-complete dictionary. An adaptive morphological over-complete dictionary is trained and constructed online according to the content of infrared image by K-singular value decomposition (K-SVD) algorithm. Then the adaptive morphological over-complete dictionary is divided automatically into a target over-complete dictionary describing target signals, and a background over-complete dictionary embedding background by the criteria that the atoms in the target over-complete dictionary could be decomposed more sparsely based on a Gaussian over-complete dictionary than the one in the background over-complete dictionary. This discriminative over-complete dictionary can not only capture significant features of background clutter and dim targets better than a structural over-complete dictionary, but also strengthens the sparse feature difference between background and target more efficiently than a discriminative over-complete dictionary learned offline and classified manually. The target and background clutter can be sparsely decomposed over their corresponding over-complete dictionaries, yet couldn't be sparsely decomposed based on their opposite over-complete dictionary, so their residuals after reconstruction by the prescribed number of target and background atoms differ very visibly. Some experiments are included and the results show that this proposed approach could not only improve the sparsity more efficiently, but also enhance the performance of small target detection more effectively.

  15. Sparse Representation for Infrared Dim Target Detection via a Discriminative Over-Complete Dictionary Learned Online

    Directory of Open Access Journals (Sweden)

    Zheng-Zhou Li

    2014-05-01

    Full Text Available It is difficult for structural over-complete dictionaries such as the Gabor function and discriminative over-complete dictionary, which are learned offline and classified manually, to represent natural images with the goal of ideal sparseness and to enhance the difference between background clutter and target signals. This paper proposes an infrared dim target detection approach based on sparse representation on a discriminative over-complete dictionary. An adaptive morphological over-complete dictionary is trained and constructed online according to the content of infrared image by K-singular value decomposition (K-SVD algorithm. Then the adaptive morphological over-complete dictionary is divided automatically into a target over-complete dictionary describing target signals, and a background over-complete dictionary embedding background by the criteria that the atoms in the target over-complete dictionary could be decomposed more sparsely based on a Gaussian over-complete dictionary than the one in the background over-complete dictionary. This discriminative over-complete dictionary can not only capture significant features of background clutter and dim targets better than a structural over-complete dictionary, but also strengthens the sparse feature difference between background and target more efficiently than a discriminative over-complete dictionary learned offline and classified manually. The target and background clutter can be sparsely decomposed over their corresponding over-complete dictionaries, yet couldn’t be sparsely decomposed based on their opposite over-complete dictionary, so their residuals after reconstruction by the prescribed number of target and background atoms differ very visibly. Some experiments are included and the results show that this proposed approach could not only improve the sparsity more efficiently, but also enhance the performance of small target detection more effectively.

  16. Video digitizer (real time-frame grabber) with region of interest suitable for quantitative data analysis used on the infrared and H alpha cameras installed on the DIII-D experiment

    International Nuclear Information System (INIS)

    Ferguson, S.W.; Kevan, D.K.; Hill, D.N.; Allen, S.L.

    1987-01-01

    This paper describes a CAMAC based video digitizer with region of interest (ROI) capability that was designed for use with the infrared and H alpha cameras installed by Lawrence Livermore Laboratory on the DIII-D experiment at G.A. Technologies in San Diego, California. The video digitizer uses a custom built CAMAC video synchronizer module to clock data into a CAMAC transient recorder on a line-by-line basis starting at the beginning of a field. The number of fields that are recorded is limited only by the available transient recorder memory. In order to conserve memory, the CAMAC video synchronizer module provides for the alternative selection of a specific region of interest in each successive field to be recorded. Memory conservation can be optimized by specifying lines in the field, start time, stop time, and the number of data samples per line. This video frame grabber has proved versatile for capturing video in such diverse applications as recording video fields from a video tape recorder played in slow motion or recording video fields in real time during a DIII-D shot. In other cases, one or more lines of video are recorded per frame to give a cross sectional slice of the plasma. Since all the data in the digitizer memory is synchronized to video fields and lines, the data can be read directly into the control computer in the proper matrix format to facilitate rapid processing, display, and permanent storage

  17. Infrared laser diagnostics for ITER

    International Nuclear Information System (INIS)

    Hutchinson, D.P.; Richards, R.K.; Ma, C.H.

    1995-01-01

    Two infrared laser-based diagnostics are under development at ORNL for measurements on burning plasmas such as ITER. The primary effort is the development of a CO 2 laser Thomson scattering diagnostic for the measurement of the velocity distribution of confined fusion-product alpha particles. Key components of the system include a high-power, single-mode CO 2 pulsed laser, an efficient optics system for beam transport and a multichannel low-noise infrared heterodyne receiver. A successful proof-of-principle experiment has been performed on the Advanced Toroidal Facility (ATF) stellerator at ORNL utilizing scattering from electron plasma frequency satellites. The diagnostic system is currently being installed on Alcator C-Mod at MIT for measurements of the fast ion tail produced by ICRH heating. A second diagnostic under development at ORNL is an infrared polarimeter for Faraday rotation measurements in future fusion experiments. A preliminary feasibility study of a CO 2 laser tangential viewing polarimeter for measuring electron density profiles in ITER has been completed. For ITER plasma parameters and a polarimeter wavelength of 10.6 microm, a Faraday rotation of up to 26 degree is predicted. An electro-optic polarization modulation technique has been developed at ORNL. Laboratory tests of this polarimeter demonstrated a sensitivity of ≤ 0.01 degree. Because of the similarity in the expected Faraday rotation in ITER and Alcator C-Mod, a collaboration between ORNL and the MIT Plasma Fusion Center has been undertaken to test this polarimeter system on Alcator C-Mod. A 10.6 microm polarimeter for this measurement has been constructed and integrated into the existing C-Mod multichannel two-color interferometer. With present experimental parameters for C-Mod, the predicted Faraday rotation was on the order of 0.1 degree. Significant output signals were observed during preliminary tests. Further experiment and detailed analyses are under way

  18. Design of a multiband near-infrared sky brightness monitor using an InSb detector.

    Science.gov (United States)

    Dong, Shu-Cheng; Wang, Jian; Tang, Qi-Jie; Jiang, Feng-Xin; Chen, Jin-Ting; Zhang, Yi-Hao; Wang, Zhi-Yue; Chen, Jie; Zhang, Hong-Fei; Jiang, Hai-Jiao; Zhu, Qing-Feng; Jiang, Peng; Ji, Tuo

    2018-02-01

    Infrared sky background level is an important parameter of infrared astronomy observations from the ground, particularly for a candidate site of an infrared capable observatory since low background level is required for such a site. The Chinese astronomical community is looking for a suitable site for a future 12 m telescope, which is designed for working in both optical and infrared wavelengths. However, none of the proposed sites has been tested for infrared observations. Nevertheless, infrared sky background measurements are also important during the design of infrared observing instruments. Based on the requirement, in order to supplement the current site survey data and guide the design of future infrared instruments, a multiband near-infrared sky brightness monitor (MNISBM) based on an InSb sensor is designed in this paper. The MNISBM consists of an optical system, mechanical structure and control system, detector and cooler, high gain readout electronics, and operational software. It is completed and tested in the laboratory. The results show that the sensitivity of the MNISBM meets the requirements of the measurement of near-infrared sky background level of several well-known astronomical infrared observing sites.

  19. Design of a multiband near-infrared sky brightness monitor using an InSb detector

    Science.gov (United States)

    Dong, Shu-cheng; Wang, Jian; Tang, Qi-jie; Jiang, Feng-xin; Chen, Jin-ting; Zhang, Yi-hao; Wang, Zhi-yue; Chen, Jie; Zhang, Hong-fei; Jiang, Hai-jiao; Zhu, Qing-feng; Jiang, Peng; Ji, Tuo

    2018-02-01

    Infrared sky background level is an important parameter of infrared astronomy observations from the ground, particularly for a candidate site of an infrared capable observatory since low background level is required for such a site. The Chinese astronomical community is looking for a suitable site for a future 12 m telescope, which is designed for working in both optical and infrared wavelengths. However, none of the proposed sites has been tested for infrared observations. Nevertheless, infrared sky background measurements are also important during the design of infrared observing instruments. Based on the requirement, in order to supplement the current site survey data and guide the design of future infrared instruments, a multiband near-infrared sky brightness monitor (MNISBM) based on an InSb sensor is designed in this paper. The MNISBM consists of an optical system, mechanical structure and control system, detector and cooler, high gain readout electronics, and operational software. It is completed and tested in the laboratory. The results show that the sensitivity of the MNISBM meets the requirements of the measurement of near-infrared sky background level of several well-known astronomical infrared observing sites.

  20. Theories of cometary origin and the brightness of the infrared sky

    International Nuclear Information System (INIS)

    Bailey, M.E.

    1983-01-01

    The far-infrared flux produced by a power-law density distribution of comets surrounding the planetary system is calculated. If the comet cloud is as massive and as dense as some recent ideas suggest, the total contribution by comets to the far-infrared background radiation may be significant and could be detected using current observational techniques. In this way observations of the infrared background could constrain theories of Solar System and cometary origins. (author)

  1. Towards a High Temporal Frequency Grass Canopy Thermal IR Model for Background Signatures

    Science.gov (United States)

    Ballard, Jerrell R., Jr.; Smith, James A.; Koenig, George G.

    2004-01-01

    In this paper, we present our first results towards understanding high temporal frequency thermal infrared response from a dense plant canopy and compare the application of our model, driven both by slowly varying, time-averaged meteorological conditions and by high frequency measurements of local and within canopy profiles of relative humidity and wind speed, to high frequency thermal infrared observations. Previously, we have employed three-dimensional ray tracing to compute the intercepted and scattered radiation fluxes and for final scene rendering. For the turbulent fluxes, we employed simple resistance models for latent and sensible heat with one-dimensional profiles of relative humidity and wind speed. Our modeling approach has proven successful in capturing the directional and diurnal variation in background thermal infrared signatures. We hypothesize that at these scales, where the model is typically driven by time-averaged, local meteorological conditions, the primary source of thermal variance arises from the spatial distribution of sunlit and shaded foliage elements within the canopy and the associated radiative interactions. In recent experiments, we have begun to focus on the high temporal frequency response of plant canopies in the thermal infrared at 1 second to 5 minute intervals. At these scales, we hypothesize turbulent mixing plays a more dominant role. Our results indicate that in the high frequency domain, the vertical profile of temperature change is tightly coupled to the within canopy wind speed In the results reported here, the canopy cools from the top down with increased wind velocities and heats from the bottom up at low wind velocities. .

  2. Cosmic thermalization and the microwave background radiation

    International Nuclear Information System (INIS)

    Rana, N.C.

    1981-01-01

    A different origin of the microwave background radiation (MBR) is suggested in view of some of the difficulties associated with the standard interpretation. Extensive stellar-type nucleosynthesis could provide radiation with the requisite energy density of the MBR and its spectral features are guaranteed by adequate thermalization of the above radiation by an ambient intergalactic dust medium. This thermalization must have occurred in quite recent epochs, say around epochs of redshift z = 7. The model emerges with consistent limits on the cosmic abundance of helium, the general luminosity evolution of the extragalactic objects, the baryonic matter density in the Universe (or, equivalently the deceleration parameter) and the degree of isotropy of MBR. The model makes definite predictions on issues like the properties of the intergalactic thermalizers, the degree of isotropy of MBR at submillimetre wavelengths and cluster emission in the far infrared. (author)

  3. Fourier-transform infrared anisotropy in cross and parallel sections of tendon and articular cartilage

    Directory of Open Access Journals (Sweden)

    Bidthanapally Aruna

    2008-10-01

    Full Text Available Abstract Background Fourier Transform Infrared Imaging (FTIRI is used to investigate the amide anisotropies at different surfaces of a three-dimensional cartilage or tendon block. With the change in the polarization state of the incident infrared light, the resulting anisotropic behavior of the tissue structure is described here. Methods Thin sections (6 μm thick were obtained from three different surfaces of the canine tissue blocks and imaged at 6.25 μm pixel resolution. For each section, infrared imaging experiments were repeated thirteen times with the identical parameters except a 15° increment of the analyzer's angle in the 0° – 180° angular space. The anisotropies of amide I and amide II components were studied in order to probe the orientation of the collagen fibrils at different tissue surfaces. Results For tendon, the anisotropy of amide I and amide II components in parallel sections is comparable to that of regular sections; and tendon's cross sections show distinct, but weak anisotropic behavior for both the amide components. For articular cartilage, parallel sections in the superficial zone have the expected infrared anisotropy that is consistent with that of regular sections. The parallel sections in the radial zone, however, have a nearly isotropic amide II absorption and a distinct amide I anisotropy. Conclusion From the inconsistency in amide anisotropy between superficial to radial zone in parallel section results, a schematic model is used to explain the origins of these amide anisotropies in cartilage and tendon.

  4. Background noise levels in Europe

    OpenAIRE

    Gjestland, Truls

    2008-01-01

    - This report gives a brief overview of typical background noise levels in Europe, and suggests a procedure for the prediction of background noise levels based on population density. A proposal for the production of background noise maps for Europe is included.

  5. Barrier Infrared Detector (BIRD)

    Data.gov (United States)

    National Aeronautics and Space Administration — A recent breakthrough in MWIR detector design, has resulted in a high operating temperature (HOT) barrier infrared detector (BIRD) that is capable of spectral...

  6. Infrared emission from protostars

    International Nuclear Information System (INIS)

    Adams, F.C.; Shu, F.H.

    1985-01-01

    The emergent spectral energy distribution at infrared to radio wavelengths is calculated for the simplest theoretical construct of a low-mass protostar. It is shown that the emergent spectrum in the infrared is insensitive to the details assumed for the temperature profile as long as allowance is made for a transition from optically thick to optically thin conditions and luminosity conservation isenforced at the inner and outer shells. The radiation in the far infrared and submillimeter wavelengths depends on the exact assumptions made for grain opacities at low frequencies. An atlas of emergent spectral energy distributions is presented for a grid of values of the instantaneous mass of the protostar and the mass infall rate. The attenuated contribution of the accretion shock to the near-infrared radiation is considered. 50 references

  7. Additive Manufacturing Infrared Inspection

    Science.gov (United States)

    Gaddy, Darrell; Nettles, Mindy

    2015-01-01

    The Additive Manufacturing Infrared Inspection Task started the development of a real-time dimensional inspection technique and digital quality record for the additive manufacturing process using infrared camera imaging and processing techniques. This project will benefit additive manufacturing by providing real-time inspection of internal geometry that is not currently possible and reduce the time and cost of additive manufactured parts with automated real-time dimensional inspections which deletes post-production inspections.

  8. Infrared image enhancement with learned features

    Science.gov (United States)

    Fan, Zunlin; Bi, Duyan; Ding, Wenshan

    2017-11-01

    Due to the variation of imaging environment and limitations of infrared imaging sensors, infrared images usually have some drawbacks: low contrast, few details and indistinct edges. Hence, to promote the applications of infrared imaging technology, it is essential to improve the qualities of infrared images. To enhance image details and edges adaptively, we propose an infrared image enhancement method under the proposed image enhancement scheme. On the one hand, on the assumption of high-quality image taking more evident structure singularities than low-quality images, we propose an image enhancement scheme that depends on the extractions of structure features. On the other hand, different from the current image enhancement algorithms based on deep learning networks that try to train and build the end-to-end mappings on improving image quality, we analyze the significance of first layer in Stacked Sparse Denoising Auto-encoder and propose a novel feature extraction for the proposed image enhancement scheme. Experiment results prove that the novel feature extraction is free from some artifacts on the edges such as blocking artifacts, ;gradient reversal;, and pseudo contours. Compared with other enhancement methods, the proposed method achieves the best performance in infrared image enhancement.

  9. The Andromeda Optical and Infrared Disk Survey

    Science.gov (United States)

    Sick, J.; Courteau, S.; Cuillandre, J.-C.

    2014-03-01

    The Andromeda Optical and Infrared Disk Survey has mapped M31 in u* g' r' i' JKs wavelengths out to R = 40 kpc using the MegaCam and WIRCam wide-field cameras on the Canada-France-Hawaii Telescope. Our survey is uniquely designed to simultaneously resolve stars while also carefully reproducing the surface brightness of M31, allowing us to study M31's global structure in the context of both resolved stellar populations and spectral energy distributions. We use the Elixir-LSB method to calibrate the optical u* g' r' i' images by building real-time maps of the sky background with sky-target nodding. These maps are stable to μg ≲ 28.5 mag arcsec-2 and reveal warps in the outer M31 disk in surface brightness. The equivalent WIRCam mapping in the near-infrared uses a combination of sky-target nodding and image-to-image sky offset optimization to produce stable surface brightnesses. This study enables a detailed analysis of the systematics of spectral energy distribution fitting with near-infrared bands where asymptotic giant branch stars impose a significant, but ill-constrained, contribution to the near-infrared light of a galaxy. Here we present panchromatic surface brightness maps and initial results from our near-infrared resolved stellar catalog.

  10. Plenoptic background oriented schlieren imaging

    International Nuclear Information System (INIS)

    Klemkowsky, Jenna N; Fahringer, Timothy W; Clifford, Christopher J; Thurow, Brian S; Bathel, Brett F

    2017-01-01

    The combination of the background oriented schlieren (BOS) technique with the unique imaging capabilities of a plenoptic camera, termed plenoptic BOS, is introduced as a new addition to the family of schlieren techniques. Compared to conventional single camera BOS, plenoptic BOS is capable of sampling multiple lines-of-sight simultaneously. Displacements from each line-of-sight are collectively used to build a four-dimensional displacement field, which is a vector function structured similarly to the original light field captured in a raw plenoptic image. The displacement field is used to render focused BOS images, which qualitatively are narrow depth of field slices of the density gradient field. Unlike focused schlieren methods that require manually changing the focal plane during data collection, plenoptic BOS synthetically changes the focal plane position during post-processing, such that all focal planes are captured in a single snapshot. Through two different experiments, this work demonstrates that plenoptic BOS is capable of isolating narrow depth of field features, qualitatively inferring depth, and quantitatively estimating the location of disturbances in 3D space. Such results motivate future work to transition this single-camera technique towards quantitative reconstructions of 3D density fields. (paper)

  11. Concerning background from calorimeter ports

    International Nuclear Information System (INIS)

    Digiacomo, N.J.

    1985-01-01

    Any detector system viewing a port or slit in a calorimeter wall will see, in addition to the primary particles of interest, a background of charged and neutral particles and photons generated by scattering from the port walls and by leakage from incompletely contained primary particle showers in the calorimeter near the port. The signal to noise ratio attainable outside the port is a complex function of the primary source spectrum, the calorimeter and port design and, of course, the nature and acceptance of the detector system that views the port. Rather than making general statements about the overall suitability (or lack thereof) of calorimeter ports, we offer here a specific example based on the external spectrometer and slit of the NA34 experiment. This combination of slit and spectrometer is designed for fixed-target work, so that the primary particle momentum spectrum contains higher momentum particles than expected in a heavy ion colliding beam environment. The results are, nevertheless, quite relevant for the collider case

  12. A fuzzy automated object classification by infrared laser camera

    Science.gov (United States)

    Kanazawa, Seigo; Taniguchi, Kazuhiko; Asari, Kazunari; Kuramoto, Kei; Kobashi, Syoji; Hata, Yutaka

    2011-06-01

    Home security in night is very important, and the system that watches a person's movements is useful in the security. This paper describes a classification system of adult, child and the other object from distance distribution measured by an infrared laser camera. This camera radiates near infrared waves and receives reflected ones. Then, it converts the time of flight into distance distribution. Our method consists of 4 steps. First, we do background subtraction and noise rejection in the distance distribution. Second, we do fuzzy clustering in the distance distribution, and form several clusters. Third, we extract features such as the height, thickness, aspect ratio, area ratio of the cluster. Then, we make fuzzy if-then rules from knowledge of adult, child and the other object so as to classify the cluster to one of adult, child and the other object. Here, we made the fuzzy membership function with respect to each features. Finally, we classify the clusters to one with the highest fuzzy degree among adult, child and the other object. In our experiment, we set up the camera in room and tested three cases. The method successfully classified them in real time processing.

  13. Backgrounder

    International Development Research Centre (IDRC) Digital Library (Canada)

    IDRC CRDI

    Center for Mountain Ecosystem Studies, Kunming Institute of Botany of the Chinese Academy of Sciences, China: $1,526,000 to inform effective water governance in the Asian highlands of China, Nepal, and Pakistan. • Ashoka Trust for Research in Ecology and the Environment (ATREE), India: $1,499,300 for research on ...

  14. Backgrounder

    International Development Research Centre (IDRC) Digital Library (Canada)

    IDRC CRDI

    Safe and Inclusive Cities: ... improving urban environments and public spaces might have on reducing the city's high ... violence against women among urban youth of working class neighbourhoods of Islamabad, Rawalpindi, and Karachi,.

  15. BACKGROUNDER

    International Development Research Centre (IDRC) Digital Library (Canada)

    IDRC CRDI

    CARIAA's research agenda addresses gaps and priorities highlighted in the ... Research focuses on climate risk, institutional and regulatory frameworks, markets, and ... The researchers will identify relevant drivers and trends and use develop ...

  16. BACKGROUNDER

    International Development Research Centre (IDRC) Digital Library (Canada)

    Corey Piccioni

    achieving long‐term food security in Africa, with a focus on post‐harvest loss, ... nutrion and health, and the socio‐economic factors that affect food supply ... Water use. Agricultural producvity in sub‐Saharan Africa is the lowest in the world.

  17. Infrared Drying Parameter Optimization

    Science.gov (United States)

    Jackson, Matthew R.

    In recent years, much research has been done to explore direct printing methods, such as screen and inkjet printing, as alternatives to the traditional lithographic process. The primary motivation is reduction of the material costs associated with producing common electronic devices. Much of this research has focused on developing inkjet or screen paste formulations that can be printed on a variety of substrates, and which have similar conductivity performance to the materials currently used in the manufacturing of circuit boards and other electronic devices. Very little research has been done to develop a process that would use direct printing methods to manufacture electronic devices in high volumes. This study focuses on developing and optimizing a drying process for conductive copper ink in a high volume manufacturing setting. Using an infrared (IR) dryer, it was determined that conductive copper prints could be dried in seconds or minutes as opposed to tens of minutes or hours that it would take with other drying devices, such as a vacuum oven. In addition, this study also identifies significant parameters that can affect the conductivity of IR dried prints. Using designed experiments and statistical analysis; the dryer parameters were optimized to produce the best conductivity performance for a specific ink formulation and substrate combination. It was determined that for an ethylene glycol, butanol, 1-methoxy 2- propanol ink formulation printed on Kapton, the optimal drying parameters consisted of a dryer height of 4 inches, a temperature setting between 190 - 200°C, and a dry time of 50-65 seconds depending on the printed film thickness as determined by the number of print passes. It is important to note that these parameters are optimized specifically for the ink formulation and substrate used in this study. There is still much research that needs to be done into optimizing the IR dryer for different ink substrate combinations, as well as developing a

  18. Cosmic microwave background power asymmetry from non-Gaussian modulation.

    Science.gov (United States)

    Schmidt, Fabian; Hui, Lam

    2013-01-04

    Non-Gaussianity in the inflationary perturbations can couple observable scales to modes of much longer wavelength (even superhorizon), leaving as a signature a large-angle modulation of the observed cosmic microwave background power spectrum. This provides an alternative origin for a power asymmetry that is otherwise often ascribed to a breaking of statistical isotropy. The non-Gaussian modulation effect can be significant even for typical ~10(-5) perturbations while respecting current constraints on non-Gaussianity if the squeezed limit of the bispectrum is sufficiently infrared divergent. Just such a strongly infrared-divergent bispectrum has been claimed for inflation models with a non-Bunch-Davies initial state, for instance. Upper limits on the observed cosmic microwave background power asymmetry place stringent constraints on the duration of inflation in such models.

  19. Background current of radioisotope manometer

    International Nuclear Information System (INIS)

    Vydrik, A.A.

    1987-01-01

    The technique for calculating the main component of the background current of radioisotopic monometers, current from direct collision of ionizing particles and a collector, is described. The reasons for appearance of background photoelectron current are clarified. The most effective way of eliminating background current components is collector protection from the source by a screen made of material with a high gamma-quanta absorption coefficient, such as lead, for example

  20. Non-collision backgrounds in ATLAS

    CERN Document Server

    Gibson, S M; The ATLAS collaboration

    2012-01-01

    The proton-proton collision events recorded by the ATLAS experiment are on top of a background that is due to both collision debris and non-collision components. The latter comprises of three types: beam-induced backgrounds, cosmic particles and detector noise. We present studies that focus on the first two of these. We give a detailed description of beam-related and cosmic backgrounds based on the full 2011 ATLAS data set, and present their rates throughout the whole data-taking period. Studies of correlations between tertiary proton halo and muon backgrounds, as well as, residual pressure and resulting beam-gas events seen in beam-condition monitors will be presented. Results of simulations based on the LHC geometry and its parameters will be presented. They help to better understand the features of beam-induced backgrounds in each ATLAS sub-detector. The studies of beam-induced backgrounds in ATLAS reveal their characteristics and serve as a basis for designing rejection tools that can be applied in physic...

  1. Background simulation for the GENIUS project

    International Nuclear Information System (INIS)

    Ponkratenko, O.A.; Tretyak, V.I.; Zdesenko, Yu.G.

    1999-01-01

    The background simulations for the GENIUS experiment were performed with the help of GEANT 3.21 package and event generator DECAY 4.Contributions from the cosmogenic activity produced in the Ge detectors and from its radioactive impurities as well as from contamination of the liquid nitrogen and other materials were calculated.External gamma and neutron background were taking into consideration also.The results of calculations evidently show feasibility of the GENIUS project,which can substantially promote development of modern astroparticle physics

  2. Background subtraction theory and practice

    CERN Document Server

    Elgammal, Ahmed

    2014-01-01

    Background subtraction is a widely used concept for detection of moving objects in videos. In the last two decades there has been a lot of development in designing algorithms for background subtraction, as well as wide use of these algorithms in various important applications, such as visual surveillance, sports video analysis, motion capture, etc. Various statistical approaches have been proposed to model scene backgrounds. The concept of background subtraction also has been extended to detect objects from videos captured from moving cameras. This book reviews the concept and practice of back

  3. Search for Higgs bosons in 2 lepton events and validation of a background noise detector in the DELPHI experiment; Recherche de bosons de higgs neutres dans les evenements a deux leptons isoles a LEP2 et mise au point d'un detecteur de controle du bruit de fond dans l'experience DELPHI

    Energy Technology Data Exchange (ETDEWEB)

    Lethuillier, M. [CEA/Saclay, Dept. d' Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l' Instrumentation Associee (DAPNIA), 91 - Gif-sur-Yvette (France)]|[Paris-7 Univ., 75 (France)

    1999-04-01

    This thesis presents two studies made within the DELPHI experiment in the context of the energy rise of the LEP collider. The first study concerns the setting up of a silicon plate detector that allows a continuous measurement of the background generated by the beams, particularly synchrotron radiation, the intensity of which increases strongly with the beam energy. This silicon monitor ensures a better safety of the more fragile DELPHI sub-detectors, especially the Time Projection Chamber, and gives a very precise measurement of the time of flight and energy of particles (2.1 ns and 3.6 keV resolution), thus allowing to identify the machine elements from which the background originates. The second study is devoted to the search for a neutral Higgs boson, produced in association with a Z boson decaying into an electron or a muon pair; we have searched for Higgs boson decays in b quarks, {tau} leptons or into invisible decay products as it is predicted by some supersymmetry scenarios. No signal has been observed in the 54 and 158 pb{sup -1} data recorded at {radical}s=183 and 189 GeV. Combining this result with those from other search channels, the hypothesis for a standard Higgs boson with a mass less than 94.5 GeV/c{sup 2} can be excluded at more than 95 % confidence level. In the frame of the Minimal Supersymmetric Model, this limit becomes 82.4 GeV/c{sup 2}, independently of the free parameter tan{beta}. Finally, as far as invisible decays are concerned, the limit becomes 90.2 GeV/c{sup 2}, independently of the branching ratio into invisible decay products. (author)

  4. Diffraction, chopping, and background subtraction for LDR

    Science.gov (United States)

    Wright, Edward L.

    1988-01-01

    The Large Deployable Reflector (LDR) will be an extremely sensitive infrared telescope if the noise due to the photons in the large thermal background is the only limiting factor. For observations with a 3 arcsec aperture in a broadband at 100 micrometers, a 20-meter LDR will emit 10(exp 12) per second, while the photon noise limited sensitivity in a deep survey observation will be 3,000 photons per second. Thus the background subtraction has to work at the 1 part per billion level. Very small amounts of scattered or diffracted energy can be significant if they are modulated by the chopper. The results are presented for 1-D and 2-D diffraction calculations for the lightweight, low-cost LDR concept that uses an active chopping quaternary to correct the wavefront errors introduced by the primary. Fourier transforms were used to evaluate the diffraction of 1 mm waves through this system. Unbalanced signals due to dust and thermal gradients were also studied.

  5. General Music Teachers' Backgrounds and Multicultural Repertoire Selection

    Science.gov (United States)

    Lee, Soojin

    2018-01-01

    The purpose of this qualitative study was to examine how teachers' backgrounds could contribute to their decisions to include music from diverse cultures. Analysis of interviews with three general music teachers indicated that their music training and experiences, ethnic backgrounds, and years of teaching experience may have influenced their…

  6. Application of ultraviolet and infrared radiation in food

    OpenAIRE

    D Jafarpour; M Alizadeh; F Siamak

    2018-01-01

    BACKGROUND: There are many uses of radiation in the food industry. Radiation can be considered as one of the new processes and usage of it can offer new features of food. This process in most food doesn’t leave any physical or sensory changes. Therefore, in this review article, the application of ultraviolet and infrared radiation in food was studied. Methods: Search by the keywords “Ultraviolet Radiation Infrared Radiation Food” in databases Pubmed, Scopus and Web of Sci...

  7. Infrared source test

    Energy Technology Data Exchange (ETDEWEB)

    Ott, L.

    1994-11-15

    The purpose of the Infrared Source Test (IRST) is to demonstrate the ability to track a ground target with an infrared sensor from an airplane. The system is being developed within the Advance Technology Program`s Theater Missile Defense/Unmanned Aerial Vehicle (UAV) section. The IRST payload consists of an Amber Radiance 1 infrared camera system, a computer, a gimbaled mirror, and a hard disk. The processor is a custom R3000 CPU board made by Risq Modular Systems, Inc. for LLNL. The board has ethernet, SCSI, parallel I/O, and serial ports, a DMA channel, a video (frame buffer) interface, and eight MBytes of main memory. The real-time operating system VxWorks has been ported to the processor. The application code is written in C on a host SUN 4 UNIX workstation. The IRST is the result of a combined effort by physicists, electrical and mechanical engineers, and computer scientists.

  8. Hanford Site background: Part 1, Soil background for nonradioactive analytes

    International Nuclear Information System (INIS)

    1993-04-01

    The determination of soil background is one of the most important activities supporting environmental restoration and waste management on the Hanford Site. Background compositions serve as the basis for identifying soil contamination, and also as a baseline in risk assessment processes used to determine soil cleanup and treatment levels. These uses of soil background require an understanding of the extent to which analytes of concern occur naturally in the soils. This report documents the results of sampling and analysis activities designed to characterize the composition of soil background at the Hanford Site, and to evaluate the feasibility for use as Sitewide background. The compositions of naturally occurring soils in the vadose Zone have been-determined for-nonradioactive inorganic and organic analytes and related physical properties. These results confirm that a Sitewide approach to the characterization of soil background is technically sound and is a viable alternative to the determination and use of numerous local or area backgrounds that yield inconsistent definitions of contamination. Sitewide soil background consists of several types of data and is appropriate for use in identifying contamination in all soils in the vadose zone on the Hanford Site. The natural concentrations of nearly every inorganic analyte extend to levels that exceed calculated health-based cleanup limits. The levels of most inorganic analytes, however, are well below these health-based limits. The highest measured background concentrations occur in three volumetrically minor soil types, the most important of which are topsoils adjacent to the Columbia River that are rich in organic carbon. No organic analyte levels above detection were found in any of the soil samples

  9. Backgrounds and characteristics of arsonists

    NARCIS (Netherlands)

    Labree, W.; Nijman, H.L.I.; Marle, H.J.C. van; Rassin, E.

    2010-01-01

    The aim of this study was to gain more insight in the backgrounds and characteristics of arsonists. For this, the psychiatric, psychological, personal, and criminal backgrounds of all arsonists (n = 25), sentenced to forced treatment in the maximum security forensic hospital “De Kijvelanden”, were

  10. Measurement of natural background neutron

    CERN Document Server

    Li Jain, Ping; Tang Jin Hua; Tang, E S; Xie Yan Fong

    1982-01-01

    A high sensitive neutron monitor is described. It has an approximate counting rate of 20 cpm for natural background neutrons. The pulse amplitude resolution, sensitivity and direction dependence of the monitor were determined. This monitor has been used for natural background measurement in Beijing area. The yearly average dose is given and compared with the results of KEK and CERN.

  11. Heat kernel expansion in the background field formalism

    CERN Document Server

    Barvinsky, Andrei

    2015-01-01

    Heat kernel expansion and background field formalism represent the combination of two calculational methods within the functional approach to quantum field theory. This approach implies construction of generating functionals for matrix elements and expectation values of physical observables. These are functionals of arbitrary external sources or the mean field of a generic configuration -- the background field. Exact calculation of quantum effects on a generic background is impossible. However, a special integral (proper time) representation for the Green's function of the wave operator -- the propagator of the theory -- and its expansion in the ultraviolet and infrared limits of respectively short and late proper time parameter allow one to construct approximations which are valid on generic background fields. Current progress of quantum field theory, its renormalization properties, model building in unification of fundamental physical interactions and QFT applications in high energy physics, gravitation and...

  12. Powerful infrared emitting diodes

    Directory of Open Access Journals (Sweden)

    Kogan L. M.

    2012-02-01

    Full Text Available Powerful infrared LEDs with emission wavelength 805 ± 10, 870 ± 20 and 940 ± 10 nm developed at SPC OED "OPTEL" are presented in the article. The radiant intensity of beam diode is under 4 W/sr in the continuous mode and under 100 W/sr in the pulse mode. The radiation power of wide-angle LEDs reaches 1 W in continuous mode. The external quantum efficiency of emission IR diodes runs up to 30%. There also has been created infrared diode modules with a block of flat Fresnel lenses with radiant intensity under 70 W/sr.

  13. The ZZ/WZ signal as a background to ZH/WH (ℓℓ,νν/ℓνb b¯$bar b$ searches with the CMS experiment

    Directory of Open Access Journals (Sweden)

    Vernieri Caterina

    2013-11-01

    Full Text Available The WZ/ZZ (VZ production channels with Z decaying to bottom quarks are one of the less reducible backgrounds for the standard model (SM Higgs boson search in the same event topology (VH. The study of the VZ signal described here should be considered as a validation of the analysis strategy developed for the VH search in the boosted regime. The 8 TeV data sample including 19.0 fb−1 from the 2012 running period has been analyzed in the Z(μμ, ee, ννZ and W(μν, eνZ channels and the presence of the signal has been established with a significance of 7.5σ.

  14. Far infrared observations of the galactic center

    International Nuclear Information System (INIS)

    Gatley, I.

    1977-01-01

    Maps of a region 10' in diameter around the galactic center made simultaneously in three wavelength bands at 30 μm, 50 μm, and 100 μm with approximately 1' resolution are presented, and the distribution of far infrared luminosity and color temperature across this region is derived. The position of highest far infrared surface brightness coincides with the peak of the late-type stellar distribution and with the H II region Sgr A West. The high spatial and temperature resolution of the data is used to identify features of the far infrared maps with known sources of near infrared, radio continuum, and molecular emission. The emission mechanism and energy sources for the far infrared radiation are anslyzed qualitatively, and it is concluded that all of the observed far infrared radiation from the galactic center region can be attributed to thermal emission from dust heated both by the late-type stars and by the ultraviolet sources which ionize the H II regions. A self-consistent model for the far infrared emission from the galactic center region is presented. It is found that the visual extinction across the central 10 pc of the galaxy is only about 3 magnitudes, and that the dust density is fairly uniform in this region. An upper limit of 10 7 L/sub mass/ is set on the luminosity of any presently unidentified source of 0.1 to 1 μm radiation at the galactic center. Additional maps in the vicinity of the source Sgr B2 and observations of Sgr C bring the total number of H II regions within 1 0 of the galactic center studied by the present experiment to nine. The far infrared luminosity, color temperature and optical depth of these regions and the ratio of infrared flux to radio continuum flux lie in the range characteristic of spiral arm H II regions. The far infrared results are therefore consistent with the data that the galactic center H II regions are ionized by luminous, early type stars

  15. Background Model for the Majorana Demonstrator

    Science.gov (United States)

    Cuesta, C.; Abgrall, N.; Aguayo, E.; Avignone, F. T.; Barabash, A. S.; Bertrand, F. E.; Boswell, M.; Brudanin, V.; Busch, M.; Byram, D.; Caldwell, A. S.; Chan, Y.-D.; Christofferson, C. D.; Combs, D. C.; Detwiler, J. A.; Doe, P. J.; Efremenko, Yu.; Egorov, V.; Ejiri, H.; Elliott, S. R.; Fast, J. E.; Finnerty, P.; Fraenkle, F. M.; Galindo-Uribarri, A.; Giovanetti, G. K.; Goett, J.; Green, M. P.; Gruszko, J.; Guiseppe, V. E.; Gusev, K.; Hallin, A. L.; Hazama, R.; Hegai, A.; Henning, R.; Hoppe, E. W.; Howard, S.; Howe, M. A.; Keeter, K. J.; Kidd, M. F.; Kochetov, O.; Konovalov, S. I.; Kouzes, R. T.; LaFerriere, B. D.; Leon, J.; Leviner, L. E.; Loach, J. C.; MacMullin, J.; MacMullin, S.; Martin, R. D.; Meijer, S.; Mertens, S.; Nomachi, M.; Orrell, J. L.; O'Shaughnessy, C.; Overman, N. R.; Phillips, D. G.; Poon, A. W. P.; Pushkin, K.; Radford, D. C.; Rager, J.; Rielage, K.; Robertson, R. G. H.; Romero-Romero, E.; Ronquest, M. C.; Schubert, A. G.; Shanks, B.; Shima, T.; Shirchenko, M.; Snavely, K. J.; Snyder, N.; Suriano, A. M.; Thompson, J.; Timkin, V.; Tornow, W.; Trimble, J. E.; Varner, R. L.; Vasilyev, S.; Vetter, K.; Vorren, K.; White, B. R.; Wilkerson, J. F.; Wiseman, C.; Xu, W.; Yakushev, E.; Young, A. R.; Yu, C.-H.; Yumatov, V.

    The Majorana Collaboration is constructing a system containing 40 kg of HPGe detectors to demonstrate the feasibility and potential of a future tonne-scale experiment capable of probing the neutrino mass scale in the inverted-hierarchy region. To realize this, a major goal of the Majorana Demonstrator is to demonstrate a path forward to achieving a background rate at or below 1 cnt/(ROI-t-y) in the 4 keV region of interest around the Q-value at 2039 keV. This goal is pursued through a combination of a significant reduction of radioactive impurities in construction materials with analytical methods for background rejection, for example using powerful pulse shape analysis techniques profiting from the p-type point contact HPGe detectors technology. The effectiveness of these methods is assessed using simulations of the different background components whose purity levels are constrained from radioassay measurements.

  16. Studies for reconstruction efficiency and background measurements of {tau} lepton identification in Z {yields} {tau}{tau} decays in data of the ATLAS experiment; Studien zur Messung von Rekonstruktionseffizienz und Untergrund der {tau}-Lepton-Identifikation im Zerfall Z {yields} {tau}{tau} beim ATLAS-Experiment aus Daten

    Energy Technology Data Exchange (ETDEWEB)

    Johnert, Sebastian

    2008-11-15

    In this diploma thesis two methods are presented, by which {tau} leptons shall be studied in the future data of the ATLAS experiment. The first part is formed by the determination of misidentification rates of jets from QCD 2-jet events as {tau} particles. The second part is the development of a method for the determination of the {tau} reconstruction and identification efficiency relatively to the {mu} efficiency. In this connection invariant masses from Z{yields}ll events are determined, the masses from Z{yields}{tau}{tau} events compared with those from Z{yields}ee and Z{yields}{mu}{mu}, {tau} efficiencies averaged over all ranges and in different {eta} ranges calculated as well as a mehtod for the determination of {tau} efficiencies in different transverse-momentum ranges presented. Furthermore an improved estimation of the QCD background is performed and the behaviour of the {tau} efficiency under regardment of the trigger studied. [German] In dieser Diplomarbeit werden zwei Methoden vorgestellt, mit denen {tau}-Leptonen in den zukuenftigen Daten des ATLAS-Experiments untersucht werden sollen. Den ersten Teil bildet die Bestimmung von Missidentifikationsraten von Jets aus QCD-2-Jet-Ereignissen als {tau}-Leptonen. Der zweite Teil ist die Entwicklung einer Methode zur Bestimmung der {tau}-Rekonstruktions und -Identifikationseffizienz relativ zur {mu}-Effizienz. In diesem Zusammenhang werden invariante Massen aus Z {yields} ll-Ereignissen bestimmt, die Massen aus Z {yields} {tau}{tau}-Ereignissen mit denen aus Z {yields} ee und Z {yields} {mu}{mu} verglichen, {tau}-Effizienzen gemittelt ueber alle Bereiche und in verschiedenen {eta}-Bereichen berechnet sowie eine Moeglichkeit zur Bestimmung von {tau}-Effizienzen in unterschiedlichen Transversalimpulsbereichen vorgestellt. Des Weiteren wird eine verbesserte Abschaetzung des QCD-Untergrunds vorgenommen und das Verhalten der {tau}-Effizienz unter Beruecksichtigung des Triggers untersucht. (orig.)

  17. Contribution to the G0 violation of parity experience: calculation and simulation of radiative corrections and the background noise study; Contribution a l'experience G0 de violation de la parite : calcul et simulation des corrections radiatives et etude du bruit de fond

    Energy Technology Data Exchange (ETDEWEB)

    Guler, Hayg [Univ. of Paris, Orsay (France)

    2003-12-17

    In the framework of quantum chromodynamics, the nucleon is made of three valence quarks surrpounded by a sea of gluons and quark-antiquark pairs. Only the only lightest quarks (u, d and s) contribute significantly to the nucleon properties. In Go we using the property of weak interaction to violate parity symmetry, in order to determine separately the contributions of the three types of quarks to nucleon form factors. The experiment, which takes place at Thomas Jefferson laboratory (USA), aims at measuring parity violation asymmetry in electron-proton scattering. By doing several measurements at different momentum squared of the exchanged photons and for different kinematics (forward angle when the proton is detected and backward angle it will be the electron) will permit to determine separately strange quarks electric and magnetic contributions to nucleon form factors. To extract an asymmetry with small errors, it is necessary to correct all the beam parameters, and to have high enough counting rates in detectors. A special electronics was developed to treat information coming from 16 scintillator pairs for each of the 8 sectors of the Go spectrometer. A complete calculation of radiative corrections has been clone and Monte Carlo simulations with the GEANT program has permitted to determine the shape of the experimental spectra including inelastic background. This work will allow to do a comparison between experimental data and theoretical calculations based on the Standard Model.

  18. Contribution to the G{sup 0} experiment about parity violation: calculation and simulation of radiative corrections, study of the background noise; Contribution a l'experience G{sup 0} de violation de la parite: calcul et simulation des corrections radiatives et etude de bruit de fond

    Energy Technology Data Exchange (ETDEWEB)

    Guler, H

    2003-12-01

    In the framework of quantum chromodynamics, the nucleon is made of three valence quarks surrounded by a sea of gluons and quark-antiquark pairs. Only the only lightest quarks (u, d and s) contribute significantly to the nucleon properties. In G{sup 0} we use the property of weak interaction to violate parity symmetry, in order to determine separately the contributions of the three types of quarks to nucleon form factors. The experiment, which takes place at Thomas Jefferson laboratory (USA), aims at measuring parity violation asymmetry in electron-proton scattering. By doing several measurements at different momentum squared of the exchanged photons and for different kinematics (forward angle when the proton is detected and backward angle it will be the electron) will permit to determine separately strange quarks electric and magnetic contributions to nucleon form factors. To extract an asymmetry with small errors, it is necessary to correct all the beam parameters, and to have high enough counting rates in detectors. A special electronics was developed to treat information coming from 16 scintillator pairs for each of the 8 sectors of the G{sup 0} spectrometer. A complete calculation of radiative corrections has been done and Monte Carlo simulations with the GEANT program has permitted to determine the shape of the experimental spectra including inelastic background. This work will allow to do a comparison between experimental data and theoretical calculations based on the Standard Model. (author)

  19. JEM-X background models

    DEFF Research Database (Denmark)

    Huovelin, J.; Maisala, S.; Schultz, J.

    2003-01-01

    Background and determination of its components for the JEM-X X-ray telescope on INTEGRAL are discussed. A part of the first background observations by JEM-X are analysed and results are compared to predictions. The observations are based on extensive imaging of background near the Crab Nebula...... on revolution 41 of INTEGRAL. Total observing time used for the analysis was 216 502 s, with the average of 25 cps of background for each of the two JEM-X telescopes. JEM-X1 showed slightly higher average background intensity than JEM-X2. The detectors were stable during the long exposures, and weak orbital...... background was enhanced in the central area of a detector, and it decreased radially towards the edge, with a clear vignetting effect for both JEM-X units. The instrument background was weakest in the central area of a detector and showed a steep increase at the very edges of both JEM-X detectors...

  20. Parallel algorithm of real-time infrared image restoration based on total variation theory

    Science.gov (United States)

    Zhu, Ran; Li, Miao; Long, Yunli; Zeng, Yaoyuan; An, Wei

    2015-10-01

    Image restoration is a necessary preprocessing step for infrared remote sensing applications. Traditional methods allow us to remove the noise but penalize too much the gradients corresponding to edges. Image restoration techniques based on variational approaches can solve this over-smoothing problem for the merits of their well-defined mathematical modeling of the restore procedure. The total variation (TV) of infrared image is introduced as a L1 regularization term added to the objective energy functional. It converts the restoration process to an optimization problem of functional involving a fidelity term to the image data plus a regularization term. Infrared image restoration technology with TV-L1 model exploits the remote sensing data obtained sufficiently and preserves information at edges caused by clouds. Numerical implementation algorithm is presented in detail. Analysis indicates that the structure of this algorithm can be easily implemented in parallelization. Therefore a parallel implementation of the TV-L1 filter based on multicore architecture with shared memory is proposed for infrared real-time remote sensing systems. Massive computation of image data is performed in parallel by cooperating threads running simultaneously on multiple cores. Several groups of synthetic infrared image data are used to validate the feasibility and effectiveness of the proposed parallel algorithm. Quantitative analysis of measuring the restored image quality compared to input image is presented. Experiment results show that the TV-L1 filter can restore the varying background image reasonably, and that its performance can achieve the requirement of real-time image processing.

  1. The infrared retina

    International Nuclear Information System (INIS)

    Krishna, Sanjay

    2009-01-01

    As infrared imaging systems have evolved from the first generation of linear devices to the second generation of small format staring arrays to the present 'third-gen' systems, there is an increased emphasis on large area focal plane arrays (FPAs) with multicolour operation and higher operating temperature. In this paper, we discuss how one needs to develop an increased functionality at the pixel level for these next generation FPAs. This functionality could manifest itself as spectral, polarization, phase or dynamic range signatures that could extract more information from a given scene. This leads to the concept of an infrared retina, which is an array that works similarly to the human eye that has a 'single' FPA but multiple cones, which are photoreceptor cells in the retina of the eye that enable the perception of colour. These cones are then coupled with powerful signal processing techniques that allow us to process colour information from a scene, even with a limited basis of colour cones. Unlike present day multi or hyperspectral systems, which are bulky and expensive, the idea would be to build a poor man's 'infrared colour' camera. We use examples such as plasmonic tailoring of the resonance or bias dependent dynamic tuning based on quantum confined Stark effect or incorporation of avalanche gain to achieve embodiments of the infrared retina.

  2. MEGA: A Low-Background Radiation Detector

    International Nuclear Information System (INIS)

    Kazkaz, Kareem; Aalseth, Craig E.; Hossbach, Todd W.; Gehman, Victor M.; Kephart, Jeremy; Miley, Harry S.

    2004-01-01

    The multiple-element gamma assay (MEGA) is a low-background detector designed to support environmental monitoring and national security applications. MEGA also demonstrates technology needed or Majorana, a next generation neutrino mass experiment. It will also exploit multicoincidence signatures to identify specific radioactive isotopes. MEGA is expected to begin testing in late 2003 for eventual installation at the Waste Isolation Plant, Carlsbad, NM

  3. Photographic infrared spectroscopy and near infrared photometry of Be stars

    International Nuclear Information System (INIS)

    Swings, J.P.

    1976-01-01

    Two topics are tackled in this presentation: spectroscopy and photometry. The following definitions are chosen: photographic infrared spectroscopy (wavelengths Hα<=lambda<1.2 μ); near infrared photometry (wavebands: 1.6 μ<=lambda<=20 μ). Near infrared spectroscopy and photometry of classical and peculiar Be stars are discussed and some future developments in the field are outlined. (Auth.)

  4. Stochastic backgrounds of gravitational waves

    International Nuclear Information System (INIS)

    Maggiore, M.

    2001-01-01

    We review the motivations for the search for stochastic backgrounds of gravitational waves and we compare the experimental sensitivities that can be reached in the near future with the existing bounds and with the theoretical predictions. (author)

  5. Berkeley Low Background Counting Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Sensitive low background assay detectors and sample analysis are available for non-destructive direct gamma-ray assay of samples. Neutron activation analysis is also...

  6. Spectral characterization of natural backgrounds

    Science.gov (United States)

    Winkelmann, Max

    2017-10-01

    As the distribution and use of hyperspectral sensors is constantly increasing, the exploitation of spectral features is a threat for camouflaged objects. To improve camouflage materials at first the spectral behavior of backgrounds has to be known to adjust and optimize the spectral reflectance of camouflage materials. In an international effort, the NATO CSO working group SCI-295 "Development of Methods for Measurements and Evaluation of Natural Background EO Signatures" is developing a method how this characterization of backgrounds has to be done. It is obvious that the spectral characterization of a background will be quite an effort. To compare and exchange data internationally the measurements will have to be done in a similar way. To test and further improve this method an international field trial has been performed in Storkow, Germany. In the following we present first impressions and lessons learned from this field campaign and describe the data that has been measured.

  7. Infrared thermography of loose hangingwalls

    CSIR Research Space (South Africa)

    Kononov, VA

    2002-09-01

    Full Text Available This project is the continuation of GAP706 “Pre-feasibility investigation of infrared thermography for the identification of loose hangingwall and impending falls of ground”. The main concept behind the infrared thermography method...

  8. WINGS: WFIRST Infrared Nearby Galaxy Survey

    Science.gov (United States)

    Williams, Benjamin

    testing and optimizing WFIRST observing strategies and providing science guidance to trade studies of observatory requirements such as field of view, pixel scale and filter selection. First, we will perform extensive simulations of galaxies' halo substructures and stellar populations that will be used as input for optimizing observing strategies and sample selection. Second, we will develop a pipeline that optimizes stellar photometry, proper motion, and variability measurements with WFIRST. This software will: maximize data quality & scientific yield; provide essential, independent calibrations to the larger WFIRST efforts; and rapidly provide accurate photometry and astrometry to the community. Third, we will derive quantitative performance metrics to fairly evaluate trade-offs between different survey strategies and WFIRST performance capabilities. The end result of this effort will be: (1) an efficient survey strategy that maximizes the scientific yield of what would otherwise be a chaotic archive of observations from small, un-coordinated programs; (2) a suite of analysis tools and a state-of-the-art pipeline that can be deployed after launch to rapidly deliver stellar photometry to the public; (3) a platform to independently verify the calibration and point spread function modeling that are essential to the primary WFIRST goals, but that are best tested from images of stellar populations. These activities will be carried out by a Science Investigation Team that has decades of experience in using nearby galaxies to inform fundamental topics in astrophysics. This team is composed of researchers who have led the charge in observational and theoretical studies of resolved stellar populations and stellar halos. With our combined background, we are poised to take full advantage of the large field of view and high spatial resolution WFIRST will offer.

  9. Infrared spectroscopy of ionic clusters

    International Nuclear Information System (INIS)

    Price, J.M.

    1990-11-01

    This thesis describes new experiments wherein the infrared vibrational predissociation spectra of a number of mass-selected ionic cluster systems have been obtained and analyzed in the 2600 to 4000 cm -1 region. The species studied include: the hydrated hydronium ions, H 3 O + (H 2 O) 3 -10 , ammoniated ammonium ions, NH 4 + (NH 3 ) 1 -10 and cluster ions involving both water and ammonia around an ammonium ion core, (mixed clusters) NH 4 + (NH 3 ) n (H 2 O) m (n+m=4). In each case, the spectra reveal well resolved structures that can be assigned to transitions arising from the vibrational motions of both the ion core of the clusters and the surrounding neutral solvent molecules. 154 refs., 19 figs., 8 tabs

  10. Infrared spectroscopy of ionic clusters

    Energy Technology Data Exchange (ETDEWEB)

    Price, J.M. (California Univ., Berkeley, CA (USA). Dept. of Chemistry Lawrence Berkeley Lab., CA (USA))

    1990-11-01

    This thesis describes new experiments wherein the infrared vibrational predissociation spectra of a number of mass-selected ionic cluster systems have been obtained and analyzed in the 2600 to 4000 cm{sup {minus}1} region. The species studied include: the hydrated hydronium ions, H{sub 3}O{sup +} (H{sub 2}O){sub 3 {minus}10}, ammoniated ammonium ions, NH{sub 4}{sup +}(NH{sub 3}){sub 1 {minus}10} and cluster ions involving both water and ammonia around an ammonium ion core, (mixed clusters) NH{sub 4}{sup +}(NH{sub 3}){sub n}(H{sub 2}O){sub m} (n+m=4). In each case, the spectra reveal well resolved structures that can be assigned to transitions arising from the vibrational motions of both the ion core of the clusters and the surrounding neutral solvent molecules. 154 refs., 19 figs., 8 tabs.

  11. Infrared up-conversion microscope

    DEFF Research Database (Denmark)

    2014-01-01

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

  12. Infrared up-conversion telescope

    DEFF Research Database (Denmark)

    2014-01-01

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

  13. Infrared emission and extragalactic starbursts

    International Nuclear Information System (INIS)

    Telesco, C.M.

    1985-01-01

    The paper examines the belief that recent star formation plays a significant role in determining many of the infrared properties of galaxies. Pertinent types of infrared observations and the infrared properties of starbursts are briefly summarized. Recently developed models which describe the evolution of starbursts are also considered. (U.K.)

  14. The influence of interpreters' professional background and experience on the interpretation of multimodality imaging of pulmonary lesions using 18F-3'-deoxy-fluorothymidine and 18F-fluorodeoxyglucose PET/CT.

    Science.gov (United States)

    Xu, Bai-xuan; Liu, Chang-bin; Wang, Rui-min; Shao, Ming-zhe; Fu, Li-ping; Li, Yun-gang; Tian, Jia-he

    2013-01-01

    Based on the results of a recently accomplished multicenter clinical trial for the incremental value of a dual-tracer (18F-FDG and 18F-FLT), dual-modality (PET and CT) imaging in the differential diagnosis of pulmonary lesions, we investigate some issues that might affect the image interpretation and result reporting. The images were read in two separate sessions. Firstly the images were read and reported by physician(s) of the imaging center on completion of each PET/CT scanning. By the end of MCCT, all images collected during the trial were re-read by a collective of readers in an isolated, blinded, and independent way. One hundred sixty two patients successfully passed the data verification and entered into the final analysis. The primary reporting result showed adding 18F-FDG image information did not change the clinical performance much in sensitivity, specifity and accuracy, but the ratio between SUVFLT and SUVFDG did help the differentiation efficacy among the three subgroups of patients. The collective reviewing result showed the diagnostic achievement varied with reading strategies. ANOVA indicated significant differences among (18)F-FDG, (18)F-FLT in SUV (F = 14.239, p = 0.004). CT had almost the same diagnostic performance as 18F-FLT. When the 18F-FDG, 18F-FLT and CT images read in pair, both diagnostic sensitivity and specificity improved. The best diagnostic figures were obtained in full-modality strategy, when dual-tracer PET worked in combination with CT. With certain experience and training both radiologists and nuclear physicians are qualified to read and to achieve the similar diagnostic accuracy in PET/CT study. Making full use of modality combination and selecting right criteria seems more practical than professional back ground and personal experience in the new hybrid imaging technology, at least when novel tracer or application is concerned.

  15. The influence of interpreters' professional background and experience on the interpretation of multimodality imaging of pulmonary lesions using 18F-3'-deoxy-fluorothymidine and 18F-fluorodeoxyglucose PET/CT.

    Directory of Open Access Journals (Sweden)

    Bai-xuan Xu

    Full Text Available OBJECTIVE: Based on the results of a recently accomplished multicenter clinical trial for the incremental value of a dual-tracer (18F-FDG and 18F-FLT, dual-modality (PET and CT imaging in the differential diagnosis of pulmonary lesions, we investigate some issues that might affect the image interpretation and result reporting. METHODS: The images were read in two separate sessions. Firstly the images were read and reported by physician(s of the imaging center on completion of each PET/CT scanning. By the end of MCCT, all images collected during the trial were re-read by a collective of readers in an isolated, blinded, and independent way. RESULTS: One hundred sixty two patients successfully passed the data verification and entered into the final analysis. The primary reporting result showed adding 18F-FDG image information did not change the clinical performance much in sensitivity, specifity and accuracy, but the ratio between SUVFLT and SUVFDG did help the differentiation efficacy among the three subgroups of patients. The collective reviewing result showed the diagnostic achievement varied with reading strategies. ANOVA indicated significant differences among (18F-FDG, (18F-FLT in SUV (F = 14.239, p = 0.004. CT had almost the same diagnostic performance as 18F-FLT. When the 18F-FDG, 18F-FLT and CT images read in pair, both diagnostic sensitivity and specificity improved. The best diagnostic figures were obtained in full-modality strategy, when dual-tracer PET worked in combination with CT. CONCLUSIONS: With certain experience and training both radiologists and nuclear physicians are qualified to read and to achieve the similar diagnostic accuracy in PET/CT study. Making full use of modality combination and selecting right criteria seems more practical than professional back ground and personal experience in the new hybrid imaging technology, at least when novel tracer or application is concerned.

  16. From Soft Walls to Infrared Branes

    CERN Document Server

    von Gersdorff, Gero

    2010-01-01

    Five dimensional warped spaces with soft walls are generalizations of the standard Randall-Sundrum compactifications, where instead of an infrared brane one has a curvature singularity (with vanishing warp factor) at finite proper distance in the bulk. We project the physics near the singularity onto a hypersurface located a small distance away from it in the bulk. This results in a completely equivalent description of the soft wall in terms of an effective infrared brane, hiding any singular point. We perform explicitly this calculation for two classes of soft wall backgrounds used in the literature. The procedure has several advantages. It separates in a clean way the physics of the soft wall from the physics of the five dimensional bulk, facilitating a more direct comparison with standard two-brane warped compactifications. Moreover, consistent soft walls show a sort of universal behavior near the singularity which is reflected in the effective brane Lagrangian. Thirdly, for many purposes, a good approxima...

  17. Visual signal detection in structured backgrounds. II. Effects of contrast gain control, background variations, and white noise

    Science.gov (United States)

    Eckstein, M. P.; Ahumada, A. J. Jr; Watson, A. B.

    1997-01-01

    Studies of visual detection of a signal superimposed on one of two identical backgrounds show performance degradation when the background has high contrast and is similar in spatial frequency and/or orientation to the signal. To account for this finding, models include a contrast gain control mechanism that pools activity across spatial frequency, orientation and space to inhibit (divisively) the response of the receptor sensitive to the signal. In tasks in which the observer has to detect a known signal added to one of M different backgrounds grounds due to added visual noise, the main sources of degradation are the stochastic noise in the image and the suboptimal visual processing. We investigate how these two sources of degradation (contrast gain control and variations in the background) interact in a task in which the signal is embedded in one of M locations in a complex spatially varying background (structured background). We use backgrounds extracted from patient digital medical images. To isolate effects of the fixed deterministic background (the contrast gain control) from the effects of the background variations, we conduct detection experiments with three different background conditions: (1) uniform background, (2) a repeated sample of structured background, and (3) different samples of structured background. Results show that human visual detection degrades from the uniform background condition to the repeated background condition and degrades even further in the different backgrounds condition. These results suggest that both the contrast gain control mechanism and the background random variations degrade human performance in detection of a signal in a complex, spatially varying background. A filter model and added white noise are used to generate estimates of sampling efficiencies, an equivalent internal noise, an equivalent contrast-gain-control-induced noise, and an equivalent noise due to the variations in the structured background.

  18. Uncooled tunneling infrared sensor

    Science.gov (United States)

    Kenny, Thomas W. (Inventor); Kaiser, William J. (Inventor); Podosek, Judith A. (Inventor); Vote, Erika C. (Inventor); Muller, Richard E. (Inventor); Maker, Paul D. (Inventor)

    1995-01-01

    An uncooled infrared tunneling sensor in which the only moving part is a diaphragm which is deflected into contact with a micromachined silicon tip electrode prepared by a novel lithographic process. Similarly prepared deflection electrodes employ electrostatic force to control the deflection of a silicon nitride, flat diaphragm membrane. The diaphragm exhibits a high resonant frequency which reduces the sensor's sensitivity to vibration. A high bandwidth feedback circuit controls the tunneling current by adjusting the deflection voltage to maintain a constant deflection of the membrane. The resulting infrared sensor can be miniaturized to pixel dimensions smaller than 100 .mu.m. An alternative embodiment is implemented using a corrugated membrane to permit large deflection without complicated clamping and high deflection voltages. The alternative embodiment also employs a pinhole aperture in a membrane to accommodate environmental temperature variation and a sealed chamber to eliminate environmental contamination of the tunneling electrodes and undesireable accoustic coupling to the sensor.

  19. Wireless infrared computer control

    Science.gov (United States)

    Chen, George C.; He, Xiaofei

    2004-04-01

    Wireless mouse is not restricted by cable"s length and has advantage over its wired counterpart. However, all the mice available in the market have detection range less than 2 meters and angular coverage less than 180 degrees. Furthermore, commercial infrared mice are based on track ball and rollers to detect movements. This restricts them to be used in those occasions where users want to have dynamic movement, such as presentations and meetings etc. This paper presents our newly developed infrared wireless mouse, which has a detection range of 6 meters and angular coverage of 180 degrees. This new mouse uses buttons instead of traditional track ball and is developed to be a hand-held device like remote controller. It enables users to control cursor with a distance closed to computer and the mouse to be free from computer operation.

  20. Infrared Astronomy Satellite

    Science.gov (United States)

    Ferrera, G. A.

    1981-09-01

    In 1982, the Infrared Astronomy Satellite (IRAS) will be launched into a 900-km sun-synchronous (twilight) orbit to perform an unbiased, all-sky survey of the far-infrared spectrum from 8 to 120 microns. Observations telemetered to ground stations will be compiled into an IR astronomy catalog. Attention is given the cryogenically cooled, 60-cm Ritchey-Chretien telescope carried by the satellite, whose primary and secondary mirrors are fabricated from beryllium by means of 'Cryo-Null Figuring'. This technique anticipates the mirror distortions that will result from cryogenic cooling of the telescope and introduces dimensional compensations for them during machining and polishing. Consideration is also given to the interferometric characterization of telescope performance and Cryo/Thermal/Vacuum simulated space environment testing.

  1. Ultrafast infrared vibrational spectroscopy

    CERN Document Server

    Fayer, Michael D

    2013-01-01

    The past ten years or so have seen the introduction of multidimensional methods into infrared and optical spectroscopy. The technology of multidimensional spectroscopy is developing rapidly and its applications are spreading to biology and materials science. Edited by a recognized leader in the field and with contributions from top researchers, including experimentalists and theoreticians, this book presents the latest research methods and results and will serve as an excellent resource for other researchers.

  2. LOFT gamma densitometer background fluxes

    International Nuclear Information System (INIS)

    Grimesey, R.A.; McCracken, R.T.

    1978-01-01

    Background gamma-ray fluxes were calculated at the location of the γ densitometers without integral shielding at both the hot-leg and cold-leg primary piping locations. The principal sources for background radiation at the γ densitometers are 16 N activity from the primary piping H 2 O and γ radiation from reactor internal sources. The background radiation was calculated by the point-kernel codes QAD-BSA and QAD-P5A. Reasonable assumptions were required to convert the response functions calculated by point-kernel procedures into the gamma-ray spectrum from reactor internal sources. A brief summary of point-kernel equations and theory is included

  3. A definition of background independence

    International Nuclear Information System (INIS)

    Gryb, Sean

    2010-01-01

    We propose a definition for background (in)/dependence in dynamical theories of the evolution of configurations that have a continuous symmetry and test this definition on particle models and on gravity. Our definition draws from Barbour's best matching framework developed for the purpose of implementing spatial and temporal relationalism. Among other interesting theories, general relativity can be derived within this framework in novel ways. We study the detailed canonical structure of a wide range of best matching theories and show that their actions must have a local gauge symmetry. When gauge theory is derived in this way, we obtain at the same time a conceptual framework for distinguishing between background-dependent and -independent theories. Gauge invariant observables satisfying Kuchar's criterion are identified and, in simple cases, explicitly computed. We propose a procedure for inserting a global background time into temporally relational theories. Interestingly, using this procedure in general relativity leads to unimodular gravity.

  4. Infrared Constraint on Ultraviolet Theories

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, Yuhsin [Cornell Univ., Ithaca, NY (United States)

    2012-08-01

    While our current paradigm of particle physics, the Standard Model (SM), has been extremely successful at explaining experiments, it is theoretically incomplete and must be embedded into a larger framework. In this thesis, we review the main motivations for theories beyond the SM (BSM) and the ways such theories can be constrained using low energy physics. The hierarchy problem, neutrino mass and the existence of dark matter (DM) are the main reasons why the SM is incomplete . Two of the most plausible theories that may solve the hierarchy problem are the Randall-Sundrum (RS) models and supersymmetry (SUSY). RS models usually suffer from strong flavor constraints, while SUSY models produce extra degrees of freedom that need to be hidden from current experiments. To show the importance of infrared (IR) physics constraints, we discuss the flavor bounds on the anarchic RS model in both the lepton and quark sectors. For SUSY models, we discuss the difficulties in obtaining a phenomenologically allowed gaugino mass, its relation to R-symmetry breaking, and how to build a model that avoids this problem. For the neutrino mass problem, we discuss the idea of generating small neutrino masses using compositeness. By requiring successful leptogenesis and the existence of warm dark matter (WDM), we can set various constraints on the hidden composite sector. Finally, to give an example of model independent bounds from collider experiments, we show how to constrain the DM–SM particle interactions using collider results with an effective coupling description.

  5. Infrared sensing and the measurement of oil slick thickness

    International Nuclear Information System (INIS)

    Brown, H.M.; Baschuk, J.J.; Goodman, R.H.

    1998-01-01

    The issue of whether infrared images can be used to detect the thickness of a marine oil spill was discussed. Infrared images of oil spills on water show density variations because of variations in oil temperature and emissivity. These observations have been used to determine thickness variations in the oil. Experiments were conducted in a large wave basin using two typical crude oils in the thickness range of 1 mm to 10 mm. Infrared images of oil spills were recorded and simultaneous thickness measurements were made using an acoustic thickness gauge. The study showed that there is no relationship between infrared image pixel greyness and the thickness measured with an acoustic probe. It was not possible to determine the volume of a spill using infrared images. 2 refs., 1 tab., 4 figs

  6. Generative electronic background music system

    Energy Technology Data Exchange (ETDEWEB)

    Mazurowski, Lukasz [Faculty of Computer Science, West Pomeranian University of Technology in Szczecin, Zolnierska Street 49, Szczecin, PL (Poland)

    2015-03-10

    In this short paper-extended abstract the new approach to generation of electronic background music has been presented. The Generative Electronic Background Music System (GEBMS) has been located between other related approaches within the musical algorithm positioning framework proposed by Woller et al. The music composition process is performed by a number of mini-models parameterized by further described properties. The mini-models generate fragments of musical patterns used in output composition. Musical pattern and output generation are controlled by container for the mini-models - a host-model. General mechanism has been presented including the example of the synthesized output compositions.

  7. Background metric in supergravity theories

    International Nuclear Information System (INIS)

    Yoneya, T.

    1978-01-01

    In supergravity theories, we investigate the conformal anomaly of the path-integral determinant and the problem of fermion zero modes in the presence of a nontrivial background metric. Except in SO(3) -invariant supergravity, there are nonvanishing conformal anomalies. As a consequence, amplitudes around the nontrivial background metric contain unpredictable arbitrariness. The fermion zero modes which are explicitly constructed for the Euclidean Schwarzschild metric are interpreted as an indication of the supersymmetric multiplet structure of a black hole. The degree of degeneracy of a black hole is 2/sup 4n/ in SO(n) supergravity

  8. Children of ethnic minority backgrounds

    DEFF Research Database (Denmark)

    Johansen, Stine Liv

    2010-01-01

    media products and toys just as they will have knowledge of different media texts, play genres, rhymes etc. This has consequences for their ability to access social settings, for instance in play. New research in this field will focus on how children themselves make sense of this balancing of cultures......Children of ethnic minority background balance their everyday life between a cultural background rooted in their ethnic origin and a daily life in day care, schools and with peers that is founded in a majority culture. This means, among other things, that they often will have access to different...

  9. Generative electronic background music system

    International Nuclear Information System (INIS)

    Mazurowski, Lukasz

    2015-01-01

    In this short paper-extended abstract the new approach to generation of electronic background music has been presented. The Generative Electronic Background Music System (GEBMS) has been located between other related approaches within the musical algorithm positioning framework proposed by Woller et al. The music composition process is performed by a number of mini-models parameterized by further described properties. The mini-models generate fragments of musical patterns used in output composition. Musical pattern and output generation are controlled by container for the mini-models - a host-model. General mechanism has been presented including the example of the synthesized output compositions

  10. Physiologic correlates to background noise acceptance

    Science.gov (United States)

    Tampas, Joanna; Harkrider, Ashley; Nabelek, Anna

    2004-05-01

    Acceptance of background noise can be evaluated by having listeners indicate the highest background noise level (BNL) they are willing to accept while following the words of a story presented at their most comfortable listening level (MCL). The difference between the selected MCL and BNL is termed the acceptable noise level (ANL). One of the consistent findings in previous studies of ANL is large intersubject variability in acceptance of background noise. This variability is not related to age, gender, hearing sensitivity, personality, type of background noise, or speech perception in noise performance. The purpose of the current experiment was to determine if individual differences in physiological activity measured from the peripheral and central auditory systems of young female adults with normal hearing can account for the variability observed in ANL. Correlations between ANL and various physiological responses, including spontaneous, click-evoked, and distortion-product otoacoustic emissions, auditory brainstem and middle latency evoked potentials, and electroencephalography will be presented. Results may increase understanding of the regions of the auditory system that contribute to individual noise acceptance.

  11. Dim point target detection against bright background

    Science.gov (United States)

    Zhang, Yao; Zhang, Qiheng; Xu, Zhiyong; Xu, Junping

    2010-05-01

    For target detection within a large-field cluttered background from a long distance, several difficulties, involving low contrast between target and background, little occupancy, illumination ununiformity caused by vignetting of lens, and system noise, make it a challenging problem. The existing approaches to dim target detection can be roughly divided into two categories: detection before tracking (DBT) and tracking before detection (TBD). The DBT-based scheme has been widely used in practical applications due to its simplicity, but it often requires working in the situation with a higher signal-to-noise ratio (SNR). In contrast, the TBD-based methods can provide impressive detection results even in the cases of very low SNR; unfortunately, the large memory requirement and high computational load prevents these methods from real-time tasks. In this paper, we propose a new method for dim target detection. We address this problem by combining the advantages of the DBT-based scheme in computational efficiency and of the TBD-based in detection capability. Our method first predicts the local background, and then employs the energy accumulation and median filter to remove background clutter. The dim target is finally located by double window filtering together with an improved high order correlation which speeds up the convergence. The proposed method is implemented on a hardware platform and performs suitably in outside experiments.

  12. Infrared Astronomy and Star Formation

    International Nuclear Information System (INIS)

    Evans, N.J.

    1985-01-01

    Infrared astronomy is a natural tool to use in studying star formation because infrared light penetrates the surrounding dust and because protostars are expected to emit infrared light. Infrared mapping and photometry have revealed many compact sources, often embedded in more extensive warm dust associated with a molecular cloud core. More detailed study of these objects is now beginning, and traditional interpretations are being questioned. Some compact sources are now thought to be density enhancements which are not self-luminous. Infrared excesses around young stars may not always be caused by circumstellar dust; speckle measurements have shown that at least some of the excess toward T Tauri is caused by an infrared companion. Spectroscopic studies of the dense, star-forming cores and of the compact objects themselves have uncovered a wealth of new phenomena, including the widespread occurence of energetic outflows. New discoveries with IRAS and with other planned infrared telescopes will continue to advance this field. (author)

  13. X-ray Counterparts of Infrared Faint Radio Sources

    Science.gov (United States)

    Schartel, Norbert

    2011-10-01

    Infrared Faint Radio Sources (IFRS) are radio sources with extremely faint or even absent infrared emission in deep Spitzer Surveys. Models of their spectral energy distributions, the ratios of radio to infrared flux densities and their steep radio spectra strongly suggest that IFRS are AGN at high redshifts (2IFRS, but if confirmed, the increased AGN numbers at these redshifts will account for the unresolved part of the X-ray background. The identification of X-ray counterparts of IFRS is considered to be the smoking gun for this hypothesis. We propose to observe 8 IFRS using 30ks pointed observations. X-ray detections of IFRS with different ratios of radio-to-infrared fluxes, will constrain the class-specific SED.

  14. Planck intermediate results: XVII. Emission of dust in the diffuse interstellar medium from the far-infrared to microwave frequencies

    DEFF Research Database (Denmark)

    Bartlett, J.G.; Cardoso, J.-F.; Delabrouille, J.

    2014-01-01

    H-atom. The dust temperature is observed to be anti-correlated with the dust emissivity and opacity. We interpret this result as evidence of dust evolution within the diffuse ISM. The mean dust opacity is measured to be (7.1 ± 0.6) × 10-27 cm2 H-1 × (v/353 GHz) 1.53 ± 0.03for 100 ≤ v ≤ 353 GHz......The dust-Hi correlation is used to characterize the emission properties of dust in the diffuse interstellar medium (ISM) from far infrared wavelengths to microwave frequencies. The field of this investigation encompasses the part of the southern sky best suited to study the cosmic infrared...... and microwave backgrounds. We cross-correlate sky maps from Planck, the Wilkinson Microwave Anisotropy Probe (WMAP), and the diffuse infrared background experiment (DIRBE), at 17 frequencies from 23 to 3000 GHz, with the Parkes survey of the 21 cm line emission of neutral atomic hydrogen, over a contiguous area...

  15. Low Background Micromegas in CAST

    DEFF Research Database (Denmark)

    Garza, J G; Aune, S.; Aznar, F.

    2014-01-01

    Solar axions could be converted into x-rays inside the strong magnetic field of an axion helioscope, triggering the detection of this elusive particle. Low background x-ray detectors are an essential component for the sensitivity of these searches. We report on the latest developments of the Micr...

  16. Teaching about Natural Background Radiation

    Science.gov (United States)

    Al-Azmi, Darwish; Karunakara, N.; Mustapha, Amidu O.

    2013-01-01

    Ambient gamma dose rates in air were measured at different locations (indoors and outdoors) to demonstrate the ubiquitous nature of natural background radiation in the environment and to show that levels vary from one location to another, depending on the underlying geology. The effect of a lead shield on a gamma radiation field was also…

  17. Educational Choice. A Background Paper.

    Science.gov (United States)

    Quality Education for Minorities Network, Washington, DC.

    This paper addresses school choice, one proposal to address parental involvement concerns, focusing on historical background, definitions, rationale for advocating choice, implementation strategies, and implications for minorities and low-income families. In the past, transfer payment programs such as tuition tax credits and vouchers were…

  18. Kerr metric in cosmological background

    Energy Technology Data Exchange (ETDEWEB)

    Vaidya, P C [Gujarat Univ., Ahmedabad (India). Dept. of Mathematics

    1977-06-01

    A metric satisfying Einstein's equation is given which in the vicinity of the source reduces to the well-known Kerr metric and which at large distances reduces to the Robertson-Walker metric of a nomogeneous cosmological model. The radius of the event horizon of the Kerr black hole in the cosmological background is found out.

  19. Low Background Micromegas in CAST

    CERN Document Server

    Garza, J.G.; Aznar, F.; Calvet, D.; Castel, J.F.; Christensen, F.E.; Dafni, T.; Davenport, M.; Decker, T.; Ferrer-Ribas, E.; Galán, J.; García, J.A.; Giomataris, I.; Hill, R.M.; Iguaz, F.J.; Irastorza, I.G.; Jakobsen, A.C.; Jourde, D.; Mirallas, H.; Ortega, I.; Papaevangelou, T.; Pivovaroff, M.J.; Ruz, J.; Tomás, A.; Vafeiadis, T.; Vogel, J.K.

    2015-11-16

    Solar axions could be converted into x-rays inside the strong magnetic field of an axion helioscope, triggering the detection of this elusive particle. Low background x-ray detectors are an essential component for the sensitivity of these searches. We report on the latest developments of the Micromegas detectors for the CERN Axion Solar Telescope (CAST), including technological pathfinder activities for the future International Axion Observatory (IAXO). The use of low background techniques and the application of discrimination algorithms based on the high granularity of the readout have led to background levels below 10$^{-6}$ counts/keV/cm$^2$/s, more than a factor 100 lower than the first generation of Micromegas detectors. The best levels achieved at the Canfranc Underground Laboratory (LSC) are as low as 10$^{-7}$ counts/keV/cm$^2$/s, showing good prospects for the application of this technology in IAXO. The current background model, based on underground and surface measurements, is presented, as well as ...

  20. Absolute calibration and beam background of the Squid Polarimeter

    International Nuclear Information System (INIS)

    Blaskiewicz, M.M.; Cameron, P.R.; Shea, T.J.

    1996-01-01

    The problem of beam background in Squid Polarimetry is not without residual benefits. The authors may deliberately generate beam background by gently kicking the beam at the spin tune frequency. This signal may be used to accomplish a simple and accurate absolute calibration of the polarimeter. The authors present details of beam background calculations and their application to polarimeter calibration, and suggest a simple proof-of-principle accelerator experiment