530 results on '"Moseley, S. H."'
Search Results
52. The COBE Diffuse Infrared Background Experiment Search for the Cosmic Infrared Background: III. Separation of Galactic Emission from the Infrared Sky Brightness
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Arendt, R. G., Odegard, N., Weiland, J. L., Sodroski, T. J., Hauser, M. G., Dwek, E., Kelsall, T., Moseley, S. H., Silverberg, R. F., Leisawitz, D., Mitchell, K., Reach, W. T., and Wright, E. L.
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Astrophysics - Abstract
The Cosmic Infrared Background (CIB) is hidden behind veils of foreground emission from our own solar system and Galaxy. This paper describes procedures for removing the Galactic IR emission from the 1.25 - 240 micron COBE DIRBE maps as steps toward the ultimate goal of detecting the CIB. The Galactic emission models are carefully chosen and constructed so that the isotropic CIB is completely retained in the residual sky maps. We start with DIRBE data from which the scattered light and thermal emission of the interplanetary dust (IPD) cloud have already been removed. Locations affected by the emission from bright compact and stellar sources are excluded from the analysis. The unresolved emission of faint stars at near- and mid-IR wavelengths is represented by a model based on Galactic source counts. The 100 micron DIRBE observations are used as the spatial template for the interstellar medium (ISM) emission at high latitudes. Correlation of the 100 micron data with H I column density allows us to isolate the component of the observed emission that is associated with the ISM. Limits are established on the far-IR emissivity of the diffuse ionized medium, which indicate a lower emissivity per H nucleus than in the neutral medium. At 240 micron, we find that adding a second spatial template to the ISM model can greatly improve the accuracy of the model at low latitudes. The crucial product of this analysis is a set of all-sky IR maps from which the Galactic (and IPD) emission has been removed. We discuss systematic uncertainties and potential errors in the foreground subtraction process that may have an impact on studies seeking to detect the CIB in the residual maps., Comment: 46 pages using aaspp4.sty, 3 PS tables (landscape), 19 JPEG and GIF figures, accepted for publication in the Astrophysical Journal (revision adds one coauthor, includes recent references, and details caption for Fig. 1)
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- 1998
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53. Morphology of the Interstellar Cooling Lines Detected by COBE
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Bennett, C. L., Fixsen, D. J., Hinshaw, G., Mather, J. C., Moseley, S. H., Wright, E. L., Eplee, Jr., R. E., Gales, J., Hewagama, T., Isaacman, R. B., Shafer, R. A., and Turpie, K.
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Astrophysics - Abstract
The FIRAS instrument on the COBE satellite has conducted an unbiased survey of the far-infrared emission from our Galaxy. The first results of this survey were reported by Wright et al. (1991). We report the results of new analyses of this spectral survey, which includes emission lines from 158 um C+, 122 um and 205 um N+, 370 um and 609 um C, and CO J=2-1 through 5-4. We report the morphological distribution along the galactic plane (b=0) of the spectral line emission, and the high galactic latitude intensities of the C+ and 205 um N+ emission. The high galactic latitude intensity cosecant of the 158 um fine structure transition from C+ is presented, and C+ is seen to decrease more rapidly than the far infrared intensity with increasing galactic latitude. C+ and H I emission are closely correlated with a C+ cooling rate of (2.65 +/- 0.15)x10^{-26} erg/s/H-atom. We conclude that this emission arises almost entirely from the Cold Neutral Medium. The high galactic latitude intensity of the 205 um fine structure transition from N+ arises entirely from the Warm Ionized Medium, and its cosecant is presented. We estimate the total ionizing photon rate in the Galaxy to be 3.5x10^{53} ionizing photons per second, based on the 205 um N+ transition., Comment: 32 pages, 5 figures, uuencoded Postscript, COBE #93-11
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- 1993
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54. In-orbit Performance of the Near-infrared Spectrograph NIRSpec on the James Webb Space Telescope
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Böker, T., primary, Beck, T. L., additional, Birkmann, S. M., additional, Giardino, G., additional, Keyes, C., additional, Kumari, N., additional, Muzerolle, J., additional, Rawle, T., additional, Zeidler, P., additional, Abul-Huda, Y., additional, de Oliveira, C. Alves, additional, Arribas, S., additional, Bechtold, K., additional, Bhatawdekar, R., additional, Bonaventura, N., additional, Bunker, A. J., additional, Cameron, A. J., additional, Carniani, S., additional, Charlot, S., additional, Curti, M., additional, Espinoza, N., additional, Ferruit, P., additional, Franx, M., additional, Jakobsen, P., additional, Karakla, D., additional, López-Caniego, M., additional, Lützgendorf, N., additional, Maiolino, R., additional, Manjavacas, E., additional, Marston, A. P., additional, Moseley, S. H., additional, Ogle, P., additional, Perna, M., additional, Peña-Guerrero, M., additional, Pirzkal, N., additional, Plesha, R., additional, Proffitt, C. R., additional, Rauscher, B. J., additional, Rix, H.-W., additional, del Pino, B. Rodríguez, additional, Rustamkulov, Z., additional, Sabbi, E., additional, Sing, D. K., additional, Sirianni, M., additional, Plate, M. te, additional, Úbeda, L., additional, Wahlgren, G. M., additional, Wislowski, E., additional, Wu, R., additional, and Willott, Chris J., additional
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- 2023
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55. The Experiment for Cryogenic Large-Aperture Intensity Mapping (EXCLAIM)
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Ade, P. A. R, Anderson, C. J, Barrentine, E. M, Bellis, N. G, Bolatto, A. D, Breysse, P. C, Bulcha, B. T, Cataldo, G, Connors, J. A, Cursey, P. W, Ehsan, N, Grant, H. C, Essinger-Hileman, T. M, Hess, L. A, Kimball, M. O, Kogut, A. J, Lamb, A. D, Low, L. N, Mauskopf, P. D, McMahan, J, Mirzaei, M, Moseley, S. H, Mugge-Durum, J. W, Noroozian, O, Pen, U, Pullen, A. R, Rodriguez, S, Shirron, P. J, Somerville, R. S, Stevenson, T. R, Switzer, E. R, Tucker, C, Visbal, E, Volpert, C. G, Wollack, E. J, and Yang, S
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Astrophysics ,Instrumentation And Photography - Abstract
The EXperiment for Cryogenic Large-Aperture Intensity Mapping (EXCLAIM) is a cryogenic balloon-borne instrument which will survey galaxy and star formation history over cosmological time scales. Rather than identifying individual objects, EXCLAIM will be a pathfinder to demonstrate an intensity mapping approach, which measures the cumulative redshifted line emission. EXCLAIM will operate at 420-540 GHz with a spectral resolution R=512 to measure the integrated CO and [CII] in redshift windows spanning \exclaimz. CO and [CII] line emissions are key tracers of the gas phases in the interstellar medium involved in star-formation processes. EXCLAIM will shed light on questions such as why the star formation rate declines at z < 2, despite continued clustering of the dark matter. The instrument will employ an array of six superconducting integrated grating-analog spectrometers (µ-Spec) coupled to microwave kinetic inductance detectors (MKIDs). Here we present an overview of the EXCLAIM instrument design and status.
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- 2019
56. The other half of the universe?
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Moseley, S. H.
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- 2014
57. The Origins Space Telescope: Mission Concept Overview
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Leisawitz, D, Amatucci, E, Carter, R, DiPirro, M, Flores, A, Staguhn, J, Wu, C, Allen, L, Arenberg, J, Armus, L, Battersby, C, Bauer, J, Bell, R, Beltran, P, Benford, D, Bergin, E, Bradford, C. M, Bradley, D, Burgarella, D, Carey, S, Chi, D, Cooray, A, Corsetti, J, Beck, E. De, Denis, K, Dewell, L, East, M, Edgington, S, Ennico, K, Fantano, L, Feller, G, Folta, D, Fortney, J, Generie, J, Gerin, M, Granger, Z, Harpole, G, Harvey, K, Helmich, F, Hilliard, L, Howard, J, Jacoby, M, Jamil, A, Kataria, T, Knight, S, Knollenberg, P, Lightsey, P, Lipscy, S, Mamajek, E, Martins, G, Meixner, M, Melnick, G, Milam, S, Mooney, T, Moseley, S. H, Narayanan, D, Neff, S, Nguyen, T, Nordt, A, Olson, J, Padgett, D, Petach, M, Petro, S, Pohner, J, Pontoppidan, K, Pope, A, Ramspacher, D, Roellig, T, Sakon, I, Sandin, C, Sandstrom, K, Scott, D, Sheth, K, Steeves, J, Stevenson, K, Stokowski, L, Stoneking, E, Su, K, Tajdaran, K, Tompkins, S, Vieira, J, Webster, C, Wiedner, M, Wright, E. L, and Zmuidzinas, J
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Earth Resources And Remote Sensing - Abstract
The Origins Space Telescope (OST) will trace the history of our origins from the time dust and heavy elements permanently altered the cosmic landscape to present-day life. How did the universe evolve in response to its changing ingredients? How common are life-bearing planets? To accomplish its scientific objectives, OST will operate at mid- and far-infrared wavelengths and offer superlative sensitivity and new spectroscopic capabilities. The OST study team will present a scientifically compelling, executable mission concept to the 2020 Decadal Survey in Astrophysics. To understand the concept solution space, our team studied two alternative mission concepts. We report on the study approach and describe both of these concepts, give the rationale for major design decisions, and briefly describe the mission-enabling technology.
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- 2018
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58. Cosmology Large Angular Scale Surveyor (CLASS) Focal Plane Development
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Chuss, D. T., Ali, A., Amiri, M., Appel, J., Bennett, C. L., Colazo, F., Denis, K. L., Dünner, R., Essinger-Hileman, T., Eimer, J., Fluxa, P., Gothe, D., Halpern, M., Harrington, K., Hilton, G., Hinshaw, G., Hubmayr, J., Iuliano, J., Marriage, T. A., Miller, N., Moseley, S. H., Mumby, G., Petroff, M., Reintsema, C., Rostem, K., U-Yen, K., Watts, D., Wagner, E., Wollack, E. J., Xu, Z., and Zeng, L.
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- 2016
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59. Performance of Backshort-Under-Grid Kilopixel TES Arrays for HAWC+
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Staguhn, J. G., Benford, D. J., Dowell, C. D., Fixsen, D. J., Hilton, G. C., Irwin, K. D., Jhabvala, C. A., Maher, S. F., Miller, T. M., Moseley, S. H., Sharp, E. H., Runyan, M. C., and Wollack, E. J.
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- 2016
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60. Superconducting Pathways Through Kilopixel Backshort–Under–Grid Arrays
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Jhabvala, C. A., Benford, D. J., Brekosky, R. P., Costen, N. P., Datesman, A. M., Hilton, G. C., Irwin, K. D., Maher, S. F., Manos, G., Miller, T. M., Moseley, S. H., Sharp, E. H., Staguhn, J. G., Wang, F., and Wollack, E. J.
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- 2016
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61. Progress Towards Improved Analysis of TES X-ray Data Using Principal Component Analysis
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Busch, S. E., Adams, J. S., Bandler, S. R., Chervenak, J. A., Eckart, M. E., Finkbeiner, F. M., Fixsen, D. J., Kelley, R. L., Kilbourne, C. A., Lee, S.-J., Moseley, S. H., Porst, J.-P., Porter, F. S., Sadleir, J. E., and Smith, S. J.
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- 2016
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62. The Near-Infrared Spectrograph (NIRSpec) on theJames WebbSpace Telescope
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Jakobsen, P., primary, Ferruit, P., additional, Alves de Oliveira, C., additional, Arribas, S., additional, Bagnasco, G., additional, Barho, R., additional, Beck, T. L., additional, Birkmann, S., additional, Böker, T., additional, Bunker, A. J., additional, Charlot, S., additional, de Jong, P., additional, de Marchi, G., additional, Ehrenwinkler, R., additional, Falcolini, M., additional, Fels, R., additional, Franx, M., additional, Franz, D., additional, Funke, M., additional, Giardino, G., additional, Gnata, X., additional, Holota, W., additional, Honnen, K., additional, Jensen, P. L., additional, Jentsch, M., additional, Johnson, T., additional, Jollet, D., additional, Karl, H., additional, Kling, G., additional, Köhler, J., additional, Kolm, M.-G., additional, Kumari, N., additional, Lander, M. E., additional, Lemke, R., additional, López-Caniego, M., additional, Lützgendorf, N., additional, Maiolino, R., additional, Manjavacas, E., additional, Marston, A., additional, Maschmann, M., additional, Maurer, R., additional, Messerschmidt, B., additional, Moseley, S. H., additional, Mosner, P., additional, Mott, D. B., additional, Muzerolle, J., additional, Pirzkal, N., additional, Pittet, J.-F., additional, Plitzke, A., additional, Posselt, W., additional, Rapp, B., additional, Rauscher, B. J., additional, Rawle, T., additional, Rix, H.-W., additional, Rödel, A., additional, Rumler, P., additional, Sabbi, E., additional, Salvignol, J.-C., additional, Schmid, T., additional, Sirianni, M., additional, Smith, C., additional, Strada, P., additional, te Plate, M., additional, Valenti, J., additional, Wettemann, T., additional, Wiehe, T., additional, Wiesmayer, M., additional, Willott, C. J., additional, Wright, R., additional, Zeidler, P., additional, and Zincke, C., additional
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- 2022
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63. The Near-Infrared Spectrograph (NIRSpec) on the James Webb Space Telescope
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Birkmann, S. M., primary, Ferruit, P., additional, Giardino, G., additional, Nielsen, L. D., additional, García Muñoz, A., additional, Kendrew, S., additional, Rauscher, B. J., additional, Beck, T. L., additional, Keyes, C., additional, Valenti, J. A., additional, Jakobsen, P., additional, Dorner, B., additional, Alves de Oliveira, C., additional, Arribas, S., additional, Böker, T., additional, Bunker, A. J., additional, Charlot, S., additional, de Marchi, G., additional, Kumari, N., additional, López-Caniego, M., additional, Lützgendorf, N., additional, Maiolino, R., additional, Manjavacas, E., additional, Marston, A., additional, Moseley, S. H., additional, Prizkal, N., additional, Proffitt, C., additional, Rawle, T., additional, Rix, H.-W., additional, te Plate, M., additional, Sabbi, E., additional, Sirianni, M., additional, Willott, C. J., additional, and Zeidler, P., additional
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- 2022
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64. The Near-Infrared Spectrograph (NIRSpec) on theJames WebbSpace Telescope
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Böker, T., primary, Arribas, S., additional, Lützgendorf, N., additional, Alves de Oliveira, C., additional, Beck, T. L., additional, Birkmann, S., additional, Bunker, A. J., additional, Charlot, S., additional, de Marchi, G., additional, Ferruit, P., additional, Giardino, G., additional, Jakobsen, P., additional, Kumari, N., additional, López-Caniego, M., additional, Maiolino, R., additional, Manjavacas, E., additional, Marston, A., additional, Moseley, S. H., additional, Muzerolle, J., additional, Ogle, P., additional, Pirzkal, N., additional, Rauscher, B., additional, Rawle, T., additional, Rix, H.-W., additional, Sabbi, E., additional, Sargent, B., additional, Sirianni, M., additional, te Plate, M., additional, Valenti, J., additional, Willott, C. J., additional, and Zeidler, P., additional
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- 2022
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65. The Near-Infrared Spectrograph (NIRSpec) on the James Webb Space Telescope
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Ferruit, P., primary, Jakobsen, P., additional, Giardino, G., additional, Rawle, T., additional, Alves de Oliveira, C., additional, Arribas, S., additional, Beck, T. L., additional, Birkmann, S., additional, Böker, T., additional, Bunker, A. J., additional, Charlot, S., additional, de Marchi, G., additional, Franx, M., additional, Henry, A., additional, Karakla, D., additional, Kassin, S. A., additional, Kumari, N., additional, López-Caniego, M., additional, Lützgendorf, N., additional, Maiolino, R., additional, Manjavacas, E., additional, Marston, A., additional, Moseley, S. H., additional, Muzerolle, J., additional, Pirzkal, N., additional, Rauscher, B., additional, Rix, H.-W., additional, Sabbi, E., additional, Sirianni, M., additional, te Plate, M., additional, Valenti, J., additional, Willott, C. J., additional, and Zeidler, P., additional
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- 2022
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66. Brackett-γ Line Survey of the Ionized Hydrogen in the Galactic Plane
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Kutyrev, A. S., Bennett, C. L., Moseley, S. H., Reynolds, R. J., Roesler, F. L., Burton, W. B., editor, Alfaro, Emilio J., editor, Pérez, Enrique, editor, and Franco, José, editor
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- 2004
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67. Electromagnetic Design of a Magnetically-Coupled Spatial Power Combiner
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Bulcha, B, Cataldo, G, Stevenson, T. R, U-Yen, K, Moseley, S. H, and Wollack, E. J
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Electronics And Electrical Engineering - Abstract
The design of a two-dimensional beam-combining network employing a parallel-plate superconducting waveguide with a mono-crystalline silicon dielectric is presented. This novel beam-combining network structure employs an array of magnetically coupled antenna elements to achieve high coupling efficiency and full sampling of the intensity distribution while avoiding diffractive losses in the multi-mode region defined by the parallel-plate waveguide. These attributes enable the structures use in realizing compact far-infrared spectrometers for astrophysical and instrumentation applications. When configured with a suitable corporate-feed power-combiner, this fully sampled array can be used to realize a low-sidelobe apodized response without incurring a reduction in coupling efficiency. To control undesired reflections over a wide range of angles in the finite-sized parallel-plate waveguide region, a wideband meta-material electromagnetic absorber structure is implemented. This adiabatic structure absorbs greater than 99 of the power over the 1.7:1 operational band at angles ranging from normal (0 degree) to near parallel (180 degree) incidence. Design, simulations, and application of the device will be presented.
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- 2017
68. Electrostatic Microshutter Arrays
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Li, M. J, Brown, A. D, Burns, D. E, Kelly, D. P, Kim, K, Kutyrev, A. S, McCandliss, S.R, Moseley, S. H, Mikula, V, and Oh, L. H
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Engineering (General) - Abstract
Based on the Microshutter Array (MSA) subsystems developed at NASA Goddard Space Flight Center (GSFC) for the James Webb Space Telescope (JWST), Next Generation Microshutter Array (NGMSA) has been developed to be used as multi-object selectors for future telescopes in space applications. Microshutter arrays function as transmission devices. Selected shutters fully open at 90 degrees permitting income light going through, while the rest of shutters keep closed. The programmable microshutter open and close make the device perform as a multi object selector that can be used on space telescopes. Utilizing a multi object selector, the telescope efficiency can be increased to 100 times or more. Like JWST MSAs, NGMSA features torsion hinges, light shields, front and back electrodes for shutter actuation, latch, and closing. The difference is that JWST MSA utilized the magnetic actuation while NGMSA the electrostatic actuation.
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- 2017
69. Cosmic Infrared Background Fluctuations and Zodiacal Light
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Arendt, Richard G, Kashlinsky, A, Moseley, S. H, and Mather, J
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Astrophysics - Abstract
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 (near-infrared)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 (Infrared Array Camera) observations of high-latitude fields where zodiacal light is faint and not strongly varying with time. The new observations analyzed here target the COSMOS (Cosmic Evolution Survey) field at low ecliptic latitude where the zodiacal light intensity varies by factors of approximately 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 (greater than or approximately equal to 100 arcseconds) 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.
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- 2017
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70. Narrow Line X-Ray Calibration Source for High Resolution Microcalorimeters
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Hokin, M. S., McCammon, D., Morgan, K. M., Bandler, S. R., Lee, S. J., Moseley, S. H., and Smith, S. J.
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- 2014
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71. Optimal Energy Measurement in Nonlinear Systems: An Application of Differential Geometry
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Fixsen, D. J., Moseley, S. H., Gerrits, T., Lita, A. E., and Nam, S. W.
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- 2014
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72. The Space High Angular Resolution Probe for the Infrared (SHARP-IR)
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Rinehart, S. A, Rizzo, M. J, Leisawitz, D. T, Staguhn, J. G, Dipirro, M, Mentzell, J. E, Juanola-Parramon, R, Dhabal, A, Mundy, L. G, Moseley, S. H, Mather, J. C, Padgett, D. L, Stapelfeldt, K, Roberge, A, Cordiner, M, Milam, S, Veach, T, and Fixsen, Dale J
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Astrophysics - Abstract
The Space High Angular Resolution Probe for the Infrared (SHARP-IR) is a new mission currently under study. As partof the preparation for the Decadal Survey, NASA is currently undertaking studies of four major missions, but interesthas also been shown in determining if there are feasible sub-$1B missions that could provide significant scientific return.SHARP-IR is being designed as one such potential probe. In this talk, we will discuss some of the potential scientificquestions that could be addressed with the mission, the current design, and the path forward to concept maturation.
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- 2016
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73. Recovery of Large Angular Scale CMB Polarization for Instruments Employing Variable-Delay Polarization Modulators
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Miller, N. J, Chuss, D. T, Marriage, T. A, Wollack, E. J, Appel, J. W, Bennett, C. L, Eimer, J, Essinger-Hileman, T, Fixsen, D. J, Harrington, K, Moseley, S. H, Rostem, K, Switzer, E. R, and Watts, D. J
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Astrophysics - Abstract
Variable-delay Polarization Modulators (VPMs) are currently being implemented in experiments designed to measure the polarization of the cosmic microwave background on large angular scales because of their capability for providing rapid, front-end polarization modulation and control over systematic errors. Despite the advantages provided by the VPM, it is important to identify and mitigate any time-varying effects that leak into the synchronously modulated component of the signal. In this paper, the effect of emission from a 300 K VPM on the system performance is considered and addressed. Though instrument design can greatly reduce the influence of modulated VPM emission, some residual modulated signal is expected. VPM emission is treated in the presence of rotational misalignments and temperature variation. Simulations of time-ordered data are used to evaluate the effect of these residual errors on the power spectrum. The analysis and modeling in this paper guides experimentalists on the critical aspects of observations using VPMs as front-end modulators. By implementing the characterizations and controls as described, front-end VPM modulation can be very powerful for mitigating 1/ f noise in large angular scale polarimetric surveys. None of the systematic errors studied fundamentally limit the detection and characterization of B-modes on large scales for a tensor-to-scalar ratio of r= 0.01. Indeed, r less than 0.01 is achievable with commensurately improved characterizations and controls.
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- 2016
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74. Progress Towards Improved Analysis of TES X-ray Data Using Principal Component Analysis
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Busch, S. E, Adams, J. S, Bandler, S. R, Chervenak, J. A, Eckart, M. E, Finkbeiner, F. M, Fixsen, D. J, Kelley, R. L, Kilbourne, C. A, Lee, S.-J, Moseley, S. H, Porst, J.-P, Porter, F. S, and Sadleir, J. E
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Astrophysics - Abstract
The traditional method of applying a digital optimal filter to measure X-ray pulses from transition-edge sensor (TES) devices does not achieve the best energy resolution when the signals have a highly non-linear response to energy, or the noise is non-stationary during the pulse. We present an implementation of a method to analyze X-ray data from TESs, which is based upon principal component analysis (PCA). Our method separates the X-ray signal pulse into orthogonal components that have the largest variance. We typically recover pulse height, arrival time, differences in pulse shape, and the variation of pulse height with detector temperature. These components can then be combined to form a representation of pulse energy. An added value of this method is that by reporting information on more descriptive parameters (as opposed to a single number representing energy), we generate a much more complete picture of the pulse received. Here we report on progress in developing this technique for future implementation on X-ray telescopes. We used an 55Fe source to characterize Mo/Au TESs. On the same dataset, the PCA method recovers a spectral resolution that is better by a factor of two than achievable with digital optimal filters.
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- 2015
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75. Early Results From The Cosmic Background Explorer (COBE)
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Mather, J. C., Hauser, M. G., Bennett, C. L., Boggess, N. W., Cheng, E. S., Eplee, R. E., Jr., Freudenreich, H. T., Isaacman, R. B., Kelsall, T., Lisse, C. M., Moseley, S. H., Jr., Shafer, R. A., Silverberg, R. F., Spiesman, W. J., Toller, G. N., Weiland, J. L., Gulkis, S., Janssen, M., Lubin, P. M., Meyer, S. S., Weiss, R., Murdock, T. L., Smoot, G. F., Wilkinson, D. T., Wright, E. L., and Kondo, Y., editor
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- 1990
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76. The Wide-Field Infrared Explorer (Wire) Mission
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Shupe, D. L., Hacking, P. B., Herter, T., Gautier, T. N., Graf, P., Lonsdale, C. J., Stacey, G. J., Moseley, S. H., Soifer, B. T., Werner, M. W., Houck, J. R., McLean, Brian J., editor, Golombek, Daniel A., editor, Hayes, Jeffrey J. E., editor, and Payne, Harry E., editor
- Published
- 1998
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77. Scientific Results from the Cosmic Background Explorer (COBE)
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Bennett, C. L., Boggess, N. W., Cheng, E. S., Hauser, M. G., Kelsall, T., Mather, J. C., Moseley,, S. H., Murdock, T. L., Shafer, R. A., Silverberg, R. F., Smoot, G. F., Weiss, R., and Wright, E. L.
- Published
- 1993
78. ASTRONOMY: The other half of the universe?
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Moseley, S. H.
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- 2014
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79. ATLAST Detector Needs for Direct Spectroscopic Biosignature Characterization in the Visible and Near-IR
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Rauscher, Bernard J, Bolcar, Matthew R, Clampin, Mark, Domagal-Goldman, Shawn D, McElwain, Michael W, Moseley, S. H, Stahle, Carl, Stark, Christopher C, and Thronson, Harley A
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Exobiology ,Instrumentation And Photography - Abstract
Are we alone? Answering this ageless question will be a major focus for astrophysics in coming decades. Our tools will include unprecedentedly large UV-Optical-IR space telescopes working with advanced coronagraphs and starshades. Yet, these facilities will not live up to their full potential without better detectors than we have today. To inform detector development, this paper provides an overview of visible and near-IR (VISIR; lambda = 0.4 − 1.8 micrometers) detector needs for the Advanced Technology Large Aperture Space Telescope (ATLAST), specifically for spectroscopic characterization of atmospheric biosignature gasses. We also provide a brief status update on some promising detector technologies for meeting these needs in the context of a passively cooled ATLAST.
- Published
- 2015
80. Spectral Confusion for Cosmological Surveys of Redshifted C II Emission
- Author
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Kogut, A, Dwek, E, and Moseley, S. H
- Subjects
Astronomy ,Astrophysics - Abstract
Far-infrared cooling lines are ubiquitous features in the spectra of star-forming galaxies. Surveys of redshifted fine-structure lines provide a promising new tool to study structure formation and galactic evolution at redshifts including the epoch of reionization as well as the peak of star formation. Unlike neutral hydrogen surveys, where the 21 cm line is the only bright line, surveys of redshifted fine-structure lines suffer from confusion generated by line broadening, spectral overlap of different lines, and the crowding of sources with redshift. We use simulations to investigate the resulting spectral confusion and derive observing parameters to minimize these effects in pencilbeam surveys of redshifted far-IR line emission. We generate simulated spectra of the 17 brightest far-IR lines in galaxies, covering the 150-1300 μm wavelength region corresponding to redshifts 0 < z < 7, and develop a simple iterative algorithm that successfully identifies the 158 μm [C II] line and other lines. Although the [C II] line is a principal coolant for the interstellar medium, the assumption that the brightest observed lines in a given line of sight are always [C II] lines is a poor approximation to the simulated spectra once other lines are included. Blind line identification requires detection of fainter companion lines from the same host galaxies, driving survey sensitivity requirements. The observations require moderate spectral resolution 700 < R < 4000 with angular resolution between 20″ and 10′, sufficiently narrow to minimize confusion yet sufficiently large to include a statistically meaningful number of sources.
- Published
- 2015
- Full Text
- View/download PDF
81. Reconstructing Emission from Pre-Reionization Sources with Cosmic Infrared Background Fluctuation Measurements by the JWST
- Author
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Kashlinsky, A, Mather, J. C, Helgason, K, Arendt, R. G, Bromm, V, and Moseley, S. H
- Subjects
Astrophysics - Abstract
We present new methodology to use cosmic infrared background (CIB) fluctuations to probe sources at 10 less than or approx. equal to z less than or approx. equal to 30 from a James Webb Space Telescope (JWST) NIRCam configuration that will isolate known galaxies to 28 AB mag at 0.55 m. At present significant mutually consistent source-subtracted CIB fluctuations have been identified in the Spitzer and AKARI data at 25 m, but we demonstrate internal inconsistencies at shorter wavelengths in the recent CIBER data. We evaluate CIB contributions from remaining galaxies and show that the bulk of the high-z sources will be in the confusion noise of the NIRCam beam, requiring CIB studies. The accurate measurement of the angular spectrum of the fluctuations and probing the dependence of its clustering component on the remaining shot noise power would discriminate between the various currently proposed models for their origin and probe the flux distribution of its sources. We show that the contribution to CIB fluctuations from remaining galaxies is large at visible wavelengths for the current instruments precluding probing the putative Lyman-break of the CIB fluctuations. We demonstrate that with the proposed JWST configuration such measurements will enable probing the Lyman-break. We develop a Lyman-break tomography method to use the NIRCam wavelength coverage to identify or constrain, via the adjacent two-band subtraction, the history of emissions over 10 less than or approx. equal to z less than or approx. equal to 30 as the universe comes out of the Dark Ages. We apply the proposed tomography to the current SpitzerIRAC measurements at 3.6 and 4.5 m, to find that it already leads to interestingly low upper limit on emissions at z greater than or approx. equal to 30.
- Published
- 2015
- Full Text
- View/download PDF
82. Electromagnetic Design of Feedhorn-Coupled Transition-Edge Sensors for Cosmic Microwave Background Polarimetry
- Author
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Chuss, D. T., Bennett, C. L., Costen, N., Crowe, E., Denis, K., Eimer, J. R., Lourie, N., Marriage, T. A., Moseley, S. H., Rostem, K., Stevenson, T. R., Towner, D., U-Yen, K., Voellmer, G., Wollack, E. J., and Zeng, L.
- Published
- 2012
- Full Text
- View/download PDF
83. Sensitivity Measurements of a Transition-Edge Hot-Electron Microbolometer for Millimeter-Wave Astrophysical Observations
- Author
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Barrentine, E. M., Timbie, P. T., Stevenson, T. R., Ali, S., Chervenak, J. A., Wollack, E., Moseley, S. H., Allen, C. A., Hseih, W. T., Miller, T. M., Benford, D. J., and Brown, A. D.
- Published
- 2008
- Full Text
- View/download PDF
84. Design and Fabrication Highlights Enabling a 2 mm, 128 Element Bolometer Array for GISMO
- Author
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Allen, C. A., Benford, D. J., Miller, T. M., Moseley, S. H., Staguhn, J. G., and Wollack, E. J.
- Published
- 2008
- Full Text
- View/download PDF
85. Properties of Superconducting Mo, Mo2n and Trilayer Mo2n-Mo-Mo2n Thin Films
- Author
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Barrentine, E. M, Stevenson, T. R, Brown, A. D, Lowitz, A. E, Noroozian, O, U-Yen, K, Eshan, N, Hsieh, W. T, Moseley, S. H, and Wollack, E. J
- Subjects
Electronics And Electrical Engineering ,Solid-State Physics - Abstract
We present measurements of the properties of thin film superconducting Mo, Mo2N and Mo2N/Mo/Mo2N trilayers of interest for microwave kinetic inductance detector (MKID) applications. Using microwave resonator devices, we investigate the transition temperature, energy gaps, kinetic inductance, and internal quality factors of these materials. We present an Usadel-based interpretation of the trilayer transition temperature as a function of trilayer thicknesses, and a 2-gap interpretation to understand the change in kinetic inductance and internal resonance quality factor (Q) as a function of temperature.
- Published
- 2014
86. Precision Control of Thermal Transport in Cryogenic Single-Crystal Silicon Devices
- Author
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Rostem, K, Chuss, D. T, Colazo, F. A, Crowe, E. J, Denis, K. L, Lourie, N. P, Moseley, S. H, Stevenson, T. R, and Wollack, E. J
- Subjects
Astrophysics - Abstract
We report on the diffusive-ballistic thermal conductance of multi-moded single-crystal silicon beams measured below 1 K. It is shown that the phonon mean-free-path is a strong function of the surface roughness characteristics of the beams. This effect is enhanced in diffuse beams with lengths much larger than, even when the surface is fairly smooth, 510 nm rms, and the peak thermal wavelength is 0.6 microns. Resonant phonon scattering has been observed in beams with a pitted surface morphology and characteristic pit depth of 30 nm. Hence, if the surface roughness is not adequately controlled, the thermal conductance can vary significantly for diffuse beams fabricated across a wafer. In contrast, when the beam length is of order, the conductance is dominated by ballistic transport and is effectively set by the beam cross-sectional area. We have demonstrated a uniformity of +/-8% in fractional deviation for ballistic beams, and this deviation is largely set by the thermal conductance of diffuse beams that support the micro-electro-mechanical device and electrical leads. In addition, we have found no evidence for excess specific heat in single-crystal silicon membranes. This allows for the precise control of the device heat capacity with normal metal films. We discuss the results in the context of the design and fabrication of large-format arrays of far-infrared and millimeter wavelength cryogenic detectors.
- Published
- 2014
87. Successful Demonstration of an Electrostatically Actuated Microshutter System for Space Telescope Flight Missions
- Author
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Li, M. J., primary, Aguayo, E., additional, Brekosky, R. P., additional, Burns, D. E., additional, Carter, A., additional, Chang, M. P., additional, Costen, N. P., additional, Fettig, R. K., additional, Franz, D. E., additional, Greenhouse, M. A., additional, Hu, G., additional, Kim, K., additional, Kelly, D. P., additional, Kotecki, C. A., additional, Kutyrev, A. S., additional, McCandliss, S. R., additional, Miller, T. M., additional, Moseley, S. H., additional, Oh, L., additional, Ray, K., additional, Rodriguez, S., additional, Wang, F., additional, and Welch, B., additional
- Published
- 2020
- Full Text
- View/download PDF
88. Multiplexed Readout of Superconducting Bolometers
- Author
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Benford, D. J., Allen, C. A., Chervenak, J. A., Freund, M. M., Kutyrev, A. S., Moseley, S. H., Shafer, R. A., Staguhn, J. G., Grossman, E. N., Hilton, G. C., Irwin, K. D., Martinis, J. M., Nam, S. W., and Reintsema, O. D.
- Published
- 2000
- Full Text
- View/download PDF
89. Principal Components Analysis of a JWST NIRSpec Detector Subsystem
- Author
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Arendt, Richard G, Fixsen, D. J, Greenhouse, Matthew A, Lander, Matthew, Lindler, Don, Loose, Markus, Moseley, S. H, Mott, D. Brent, Rauscher, Bernard J, Wen, Yiting, Wilson, Donna V, and Xenophontos, Christos
- Subjects
Astrophysics - Abstract
We present principal component analysis (PCA) of a flight-representative James Webb Space Telescope NearInfrared Spectrograph (NIRSpec) Detector Subsystem. Although our results are specific to NIRSpec and its T - 40 K SIDECAR ASICs and 5 m cutoff H2RG detector arrays, the underlying technical approach is more general. We describe how we measured the systems response to small environmental perturbations by modulating a set of bias voltages and temperature. We used this information to compute the systems principal noise components. Together with information from the astronomical scene, we show how the zeroth principal component can be used to calibrate out the effects of small thermal and electrical instabilities to produce cosmetically cleaner images with significantly less correlated noise. Alternatively, if one were designing a new instrument, one could use a similar PCA approach to inform a set of environmental requirements (temperature stability, electrical stability, etc.) that enabled the planned instrument to meet performance requirements
- Published
- 2013
90. Cross-correlating Cosmic IR and X-ray Background Fluctuations: Evidence of Significant Black Hole Populations Among the CIB Sources
- Author
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Cappelluti, N, Kashlinsky, A, Arendt, R. G, Comastri, A, Fazio, G. G, Finoguenov, A, Hasinger, G, Mather, J. C, Miyaji, T, and Moseley, S. H
- Subjects
Astrophysics - Abstract
In order to understand the nature of the sources producing the recently uncovered cosmic infrared background (CIB) fluctuations, we study cross-correlations between the fluctuations in the source-subtracted CIB from Spitzer/IRAC data and the unresolved cosmic X-ray background from deep Chandra observations. Our study uses data from the EGS/AEGIS field, where both data sets cover an approx = 8' x 45' region of the sky. Our measurement is the cross-power spectrum between the IR and X-ray data. The cross-power signal between the IRAC maps at 3.6 micron and 4.5 micron and the Chandra [0.5-2] keV data has been detected, at angular scales approx >20'', with an overall significance of approx = 3.8 sigma and approx. = 5.6 sigma, respectively. At the same time we find no evidence of significant cross-correlations at the harder Chandra bands. The cross-correlation signal is produced by individual IR sources with 3.6 micron and 4.5 micron magnitudes m(sub AB) approx. > 25-26 and [0.5-2] keV X-ray fluxes << 7 × 10(exp -177 erg sq. cm/ s. We determine that at least 15%-25% of the large scale power of the CIB fluctuations is correlated with the spatial power spectrum of the X-ray fluctuations. If this correlation is attributed to emission from accretion processes at both IR and X-ray wavelengths, this implies a much higher fraction of accreting black holes than among the known populations. We discuss the various possible origins for the cross-power signal and show that neither local foregrounds nor the known remaining normal galaxies and active galactic nuclei can reproduce the measurements. These observational results are an important new constraint on theoretical modeling of the near-IR CIB fluctuations. local foregrounds, nor the known remaining normal galaxies and active galactic nuclei (AGN) can reproduce the measurements. These observational results are an important new constraint on theoretical modeling of the near-IR CIB fluctuations
- Published
- 2013
91. Fabrication of Silicon Backshort Assembly for Waveguide-Coupled Superconducting Detectors
- Author
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Crowe, E, Bennett, C. L, Chuss, D. T, Denis, K. L, Eimer, J, Lourie, N, Marriage, T, Moseley, S. H, Rostem, K, Stevenson, T. R, Towner, D, U-Yen, K, and Wollack, E. J
- Subjects
Electronics And Electrical Engineering - Abstract
The Cosmology Large Angular Scale Surveyor (CLASS) is a ground-based instrument that will measure the polarization of the cosmic microwave background to search for gravitational waves from a posited epoch of inflation early in the universe s history. We are currently developing detectors that address the challenges of this measurement by combining the excellent beam-forming attributes of feedhorns with the low-noise performance of Transition-Edge sensors. These detectors utilize a planar orthomode transducer that maps the horizontal and vertical linear polarized components in a dual-mode waveguide to separate microstrip lines. On-chip filters define the bandpass in each channel, and the signals are terminated in resistors that are thermally coupled to the transition-edge sensors operating at 150 mK.
- Published
- 2012
92. Fabrication of Silicon Backshorts with Improved Out-of-Band Rejection for Waveguide-Coupled Superconducting Detectors
- Author
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Crowe, E, Bennett, C. L, Chuss, D. T, Denis, K. L, Eimer, J, Lourie, N, Marriage, T, Moseley, S. H, Rostem, K, Stevenson, T. R, Towner, D, U-Yen, K, and Wollack, E. J
- Subjects
Electronics And Electrical Engineering - Published
- 2012
93. Reducing the Read Noise of HAWAII-2RG Detector Systems with Improved Reference Sampling and Subtraction (IRS2)
- Author
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Rauscher, Bernard J, Arendt, Richard G, Fixsen, D. J, Lander, Matthew, Lindler, Don, Loose, Markus, Moseley, S. H, Wilson, Donna V, and Xenophontos, Christos
- Subjects
Instrumentation And Photography - Abstract
IRS2 is a Wiener-optimal approach to using all of the reference information that Teledyne's HAWAII-2RG detector arrays provide. Using a new readout pattern, IRS2 regularly interleaves reference pixels with the normal pixels during readout. This differs from conventional clocking, in which the reference pixels are read out infrequently, and only in a few rows and columns around the outside edges of the detector array. During calibration, the data are processed in Fourier space, which is <;:lose to the noise's eigenspace. Using IRS2, we have reduced the read noise of the James Webb Space Telescope Near Infrared Spectrograph by 15% compared to conventional readout. We are attempting to achieve further gains by calibrating out recently recognized non-stationary noise that appears at the frame rate.
- Published
- 2012
94. Stray Light Suppression in the Goddard IRAM 2-Millimeter Observer (GISMO)
- Author
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Sharp, E. H, Benford, D. J, Fixsen, D. J, Moseley, S. H, Staguhn, J. G, and Wollack, E. J
- Subjects
Instrumentation And Photography - Abstract
The Goddard-IRAM Superconducting 2 Millimeter Observer (GISMO) is an 8xl6 Transition Edge Sensor (TES) array of bolometers built as a pathfinder for TES detector development efforts at NASA Goddard Space Flight Center. GISMO has been used annually at the Institut de Radioastronomie Millimetrique (IRAM) 30 meter telescope since 2007 under engineering time and was opened in the spring of 2012 to the general astronomical community. The spring deployment provided an opportunity to modify elements of the room temperature optics before moving the instrument to its new permanent position in the telescope receiver cabin. This allowed for the possibility to extend the cryostat, introduce improved cold baffling and thus further optimize the stray light performance for final astronomical use of the instrument, which has been completed and validated. We will demonstrate and discuss several of the methods used to quantify and limit the influence of stray light in the GISMO camera.
- Published
- 2012
95. Phase-Controlled Polarization Modulators
- Author
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Chuss, D. T, Wollack, E. J, Novak, G, Moseley, S. H, Pisano, G, Krejny, M, and U-Yen, K
- Subjects
Instrumentation And Photography - Abstract
We report technology development of millimeter/submillimeter polarization modulators that operate by introducing a a variable, controlled phase delay between two orthogonal polarization states. The variable-delay polarization modulator (VPM) operates via the introduction of a variable phase delay between two linear orthogonal polarization states, resulting in a variable mapping of a single linear polarization into a combination of that Stokes parameter and circular (Stokes V) polarization. Characterization of a prototype VPM is presented at 350 and 3000 microns. We also describe a modulator in which a variable phase delay is introduced between right- and left- circular polarization states. In this architecture, linear polarization is fully modulated. Each of these devices consists of a polarization diplexer parallel to and in front of a movable mirror. Modulation involves sub-wavelength translations of the mirror that change the magnitude of the phase delay.
- Published
- 2012
96. Design and Performance of Micro-Spec, an Ultra Compact High-Sensitivity Far-Infrared Spectrometer for SPICA
- Author
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Cataldo, Giuseppe, Moseley, S. H, Hsieh, W.-T, Huang, W,-C, Stevenson, T. R, and Wollak, E. J
- Subjects
Electronics And Electrical Engineering - Abstract
Micro-Spec (u-Spec) is a high-performance spectrometer working in the 250-700-micrometer wavelength range, whose modules use low-loss superconducting microstrip transmission lines on a single 4-inch-diameter silicon wafer. Creating the required phase delays in transmission lines rather than free space allows such an instrument to have, in principle, the performance of a meter-scale grating spectrometer. Such a dramatic size reduction enables classes of instruments for space that would be impossible with conventional technologies. This technology can dramatically enhance the long-wavelength capability of the space infrared telescope for cosmology and astrophysics SPICA. u-Spec is analogous to a grating spectrometer. The phase retardation generated by the reflection from the grating grooves is instead produced by propagation through a transmission line. The power received by a broadband antenna is progressively divided by binary microstrip power dividers, and the required phase delays are generated by different lengths of microstrip transmission lines. by arranging these outputs along a circular focal surface, the analog of a Rowland spectrometer can he created. The procedure to optimize the Micro-Spec design is based on the stigmatization and minimization of the light path function in a two-dimensional hounded region, which results in an optimized geometry arrangement with three stigmatic points. In addition, in order to optimize the overall efficiency of the instrument, the emitters are directed to the center of the focal surface. The electric field amplitude and phase as well as the power transmitted and absorbed throughout the region are analyzed. Measurements are planned in late summer to validate the designs.
- Published
- 2012
97. Reducing the Read Noise of the James Webb Space Telescope Near Infrared Spectrograph Detector Subsystem
- Author
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Rauscher, Bernard, Arendt, Richard G, Fixsen, D. J, Lindler, Don, Loose, Markus, Moseley, S. H, and Wilson, D. V
- Subjects
Astrophysics - Abstract
We describe a Wiener optimal approach to using the reference output and reference pixels that are built into Teledyne's HAWAII-2RG detector arrays. In this way, we are reducing the total noise per approximately 1000 second 88 frame up-the-ramp dark integration from about 6.5 e- rms to roughly 5 e- rms. Using a principal components analysis formalism, we achieved these noise improvements without altering the hardware in any way. In addition to being lower, the noise is also cleaner with much less visible correlation. For example, the faint horizontal banding that is often seen in HAWAII-2RG images is almost completely removed. Preliminary testing suggests that the relative gains are even higher when using non flight grade components. We believe that these techniques are applicable to most HAWAII-2RG based instruments.
- Published
- 2012
98. New Measurements of the Cosmic Infrared Background Fluctuations in Deep SpitzerllRAC Survey Data and their Cosmological Implications
- Author
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Kashlinsky, A, Arendt, R. G, Ashby, M. L. N, Fazio, G. G, Mather, J, and Moseley, S. H
- Subjects
Astronomy - Abstract
We extend the previous measurements of CIB fluctuations to angular scales of less than or equal to 1 degree new data obtained in the course of the 2,000+ hour Spitzer Extended Deep Survey. Two fields with completed observations of approximately equal to 12 hr/pixel are analyzed for source-subtracted CIB fluctuations at 3.6 and 4.5 micrometers. The fields, EGS and UDS, cover a total area of approximately 0.25 deg and lie at high Galactic and Ecliptic latitudes, thus minimizing cirrus and zodiacal light contributions to the fluctuations. The observations have been conducted at 3 distinct epochs separated by about 6 months. As in our previous studies, the fields were assembled using the self-calibration method which is uniquely suitable for probing faint diffuse backgrounds. The assembled fields were cleaned off the bright sources down to the low shot noise levels corresponding to AB mag approximately equal to 25, Fourier-transformed and their power spectra evaluated. The noise was estimated from the time-differenced data and subtracted from the signal isolating the fluctuations remaining above the noise levels. The power spectra of the source-subtracted fields remain identical (within the observational uncertainties) for the three epochs of observations indicating that zodiacal light contributes negligibly to the fluctuations. By comparing to the measurements for the same regions at 8 micrometers we demonstrate that Galactic cirrus cannot account for the levels of the fluctuations either. The signal appears isotropically distributed on the sky as required by its origin in the CIB fluctuations. This measurement thus extends our earlier results to the important range of sub-degree scales. We find that the CIB fluctuations continue to diverge to more than 10 times those of known galaxy populations on angular scales out to less than or equal to 1 degree. The low shot noise levels remaining in the diffuse maps indicate that the large scale fluctuations arise from spatial clustering of faint sources well within the confusion noise. The spatial spectrum of these fluctuations is in reasonable agreement with simple fitting assuming that they originate in early populations spatially distributed according to the standard cosmological model (ACDM) at epochs coinciding with the first stars era. The alternative to this identification would require a new population never observed before, nor expected on theoretical grounds, but if true this would represent an important discovery in its own right.
- Published
- 2012
99. Reducing the Read Noise of H2RG Detector Arrays by more Efficient use of Reference Signals
- Author
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Rauscher, Bernard J, Arendt, Richard G, Fixen, D. J, Lindler, Don, Loose, Markus, Moseley, S. H, and Wilson, D. V
- Subjects
Astronomy - Abstract
We present a process for characterizing the correlation properties of the noise in large two-dimensional detector arrays, and describe an efficient process for its removal. In the case of the 2k x 2k HAWAII-2RG detectors (H2RG) detectors from Teledyne which are being used on the Near Infrared Spectrograph (NIRSpec) on the James Webb Space Telescope (JWST), we find that we can reduce the read noise by thirty percent. Noise on large spatial scales is dramatically reduced. With this relatively simple process, we provide a performance improvement that is equivalent to a significant increase in telescope collecting area for high resolution spectroscopy with NIRSpec.
- Published
- 2011
100. Fabrication and Calibration of FORTIS
- Author
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Fleming, Brian T, McCandliss, Stephan R, Kaiser, Mary Elizabeth, Kruk, Jeffery, Feldman, Paul D, Kutyrev, Alexander S, Li, Mary J, Rapchun, David A, Lyness, Eric, Moseley, S. H, Siegmund, Oswald, Vallerga, John, and Martin, Adrian
- Subjects
Instrumentation And Photography - Abstract
The Johns Hopkins University sounding rocket group is entering the final fabrication phase of the Far-ultraviolet Off Rowland-circle Telescope for Imaging and Spectroscopy (FORTIS); a sounding rocket borne multi-object spectro-telescope designed to provide spectral coverage of 43 separate targets in the 900 - 1800 Angstrom bandpass over a 30' x 30' field-of-view. Using "on-the-fly" target acquisition and spectral multiplexing enabled by a GSFC microshutter array, FORTIS will be capable of observing the brightest regions in the far-UV of nearby low redshift (z approximately 0.002 - 0.02) star forming galaxies to search for Lyman alpha escape, and to measure the local gas-to-dust ratio. A large area (approximately 45 mm x 170 mm) microchannel plate detector built by Sensor Sciences provides an imaging channel for targeting flanked by two redundant spectral outrigger channels. The grating is ruled directly onto the secondary mirror to increase efficiency. In this paper, we discuss the recent progress made in the development and fabrication of FORTIS, as well as the results of early calibration and characterization of our hardware, including mirror/grating measurements, detector performance, and early operational tests of the micro shutter arrays.
- Published
- 2011
- Full Text
- View/download PDF
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