Science.gov

Sample records for deep hawk-i survey

  1. The bright end of the z ~ 7 UV luminosity function from a wide and deep HAWK-I survey

    NASA Astrophysics Data System (ADS)

    Castellano, M.; Fontana, A.; Paris, D.; Grazian, A.; Pentericci, L.; Boutsia, K.; Santini, P.; Testa, V.; Dickinson, M.; Giavalisco, M.; Bouwens, R.; Cuby, J.-G.; Mannucci, F.; Clément, B.; Cristiani, S.; Fiore, F.; Gallozzi, S.; Giallongo, E.; Maiolino, R.; Menci, N.; Moorwood, A.; Nonino, M.; Renzini, A.; Rosati, P.; Salimbeni, S.; Vanzella, E.

    2010-12-01

    Aims: We perform a deep search for galaxies in the redshift range 6.5 ≤ z ≤ 7.5 to measure the evolution of the number density of luminous galaxies in this redshift range and derive useful constraints on the evolution of their luminosity function. Methods: We present here the second half of an ESO Large Programme, which exploits the unique combination of area and sensitivity provided in the near-IR by the camera Hawk-I at the VLT. We have obtained ~ 30 observing hours with Hawk-I in the Y-band of two high galactic latitude fields. We combined the Y-band data with deep J and K Hawk-I observations, as well as FORS1/FORS2 U, B, V, R, I, and Z observations to select z-drop galaxies with Z-Y>1, no optical detection, and flat Y-J and Y-K colour terms. Results: We detect eight high-quality candidates in the magnitude range Y = 25.5-26.5 that we add to the z-drop candidates selected in two Hawk-I pointings over the GOODS-South field. We use this full sample of 15 objects found in ~161 arcmin2 of our survey to constrain the average physical properties and the evolution of the number density of z ~ 7 LBGs. A stacking analysis yields a best-fit SED with photometric redshift z = 6.85-0.15+0.20 and an E(B-V) = 0.05-0.05+0.15. We compute a binned estimate of the z ~ 7 LF and explore the effects of photometric scatter and model uncertainties on the statistical constraints. After accounting for the expected incompleteness through MonteCarlo simulations, we strengthen our previous finding that a Schechter luminosity function constant from z = 6 to z = 7 is ruled out at a ⪆99% confidence level, even including the effects of cosmic variance. For galaxies brighter than M1500 = -19.0, we derive a luminosity density ρUV = 1.5-0.8+2.1 × 1025 erg s-1 Hz-1 Mpc-3, implying a decrease by a factor 3.5 from z = 6 to z ≃ 6.8. We find that under standard assumptions, the emission rate of ionizing photons coming from UV bright galaxies is lower by at least a factor of two than the value

  2. The Hawk-I UDS and GOODS Survey (HUGS): Survey design and deep K-band number counts

    NASA Astrophysics Data System (ADS)

    Fontana, A.; Dunlop, J. S.; Paris, D.; Targett, T. A.; Boutsia, K.; Castellano, M.; Galametz, A.; Grazian, A.; McLure, R.; Merlin, E.; Pentericci, L.; Wuyts, S.; Almaini, O.; Caputi, K.; Chary, R.-R.; Cirasuolo, M.; Conselice, C. J.; Cooray, A.; Daddi, E.; Dickinson, M.; Faber, S. M.; Fazio, G.; Ferguson, H. C.; Giallongo, E.; Giavalisco, M.; Grogin, N. A.; Hathi, N.; Koekemoer, A. M.; Koo, D. C.; Lucas, R. A.; Nonino, M.; Rix, H. W.; Renzini, A.; Rosario, D.; Santini, P.; Scarlata, C.; Sommariva, V.; Stark, D. P.; van der Wel, A.; Vanzella, E.; Wild, V.; Yan, H.; Zibetti, S.

    2014-10-01

    We present the results of a new, ultra-deep, near-infrared imaging survey executed with the Hawk-I imager at the ESO VLT, of which we make all the data (images and catalog) public. This survey, named HUGS (Hawk-I UDS and GOODS Survey), provides deep, high-quality imaging in the K and Y bands over the portions of the UKIDSS UDS and GOODS-South fields covered by the CANDELS HST WFC3/IR survey. In this paper we describe the survey strategy, the observational campaign, the data reduction process, and the data quality. We show that, thanks to exquisite image quality and extremely long exposure times, HUGS delivers the deepest K-band images ever collected over areas of cosmological interest, and in general ideally complements the CANDELS data set in terms of image quality and depth. In the GOODS-S field, the K-band observations cover the whole CANDELS area with a complex geometry made of 6 different, partly overlapping pointings, in order to best match the deep and wide areas of CANDELS imaging. In the deepest region (which includes most of the Hubble Ultra Deep Field) exposure times exceed 80 hours of integration, yielding a 1 - σ magnitude limit per square arcsec of ≃28.0 AB mag. The seeing is exceptional and homogeneous across the various pointings, confined to the range 0.38-0.43 arcsec. In the UDS field the survey is about one magnitude shallower (to match the correspondingly shallower depth of the CANDELS images) but includes also Y-band band imaging (which, in the UDS, was not provided by the CANDELS WFC3/IR imaging). In the K-band, with an average exposure time of 13 hours, and seeing in the range 0.37-0.43 arcsec, the 1 - σ limit per square arcsec in the UDS imaging is ≃27.3 AB mag. In the Y-band, with an average exposure time ≃8 h, and seeing in the range 0.45-0.5 arcsec, the imaging yields a 1 - σ limit per square arcsec of ≃28.3 AB mag. We show that the HUGS observations are well matched to the depth of the CANDELS WFC3/IR data, since the majority

  3. Evidence of a fast evolution of the UV luminosity function beyond redshift 6 from a deep HAWK-I survey of the GOODS-S field

    NASA Astrophysics Data System (ADS)

    Castellano, M.; Fontana, A.; Boutsia, K.; Grazian, A.; Pentericci, L.; Bouwens, R.; Dickinson, M.; Giavalisco, M.; Santini, P.; Cristiani, S.; Fiore, F.; Gallozzi, S.; Giallongo, E.; Maiolino, R.; Mannucci, F.; Menci, N.; Moorwood, A.; Nonino, M.; Paris, D.; Renzini, A.; Rosati, P.; Salimbeni, S.; Testa, V.; Vanzella, E.

    2010-02-01

    Aims: We perform a deep search for galaxies in the redshift range 6.5≤ z≤ 7.5, to measure the evolution of the number density of luminous galaxies in this redshift range and derive useful constraints on the evolution of their luminosity function. Methods: We present here the first results of an ESO Large Programme, which exploits the unique combination of area and sensitivity provided in the near-IR by the camera Hawk-I at the VLT. We have obtained two Hawk-I pointings on the GOODS South field for a total of ˜32 observing hours, covering ˜90 arcmin^2. The images reach Y=26.7 mag for the two fields. We used public ACS images in the z band to select z-dropout galaxies with the colour criteria Z-Y≥ 1, Y-J<1.5, and Y-K<2. The other public data in the UBVRIJK bands are used to reject possible low redshift interlopers. The output has been compared with extensive Monte Carlo simulations to quantify the observational effects of our selection criteria, as well as the effects of photometric errors. Results: We detect 7 high-quality candidates in the magnitude range Y=25.5-26.7. This interval samples the critical range for M_* at z>6 (M1500≃ -19.5 to -21.5). After accounting for the expected incompleteness, we rule out a luminosity function constant from z=6 to z=7 at a 99% confidence level, even including the effects of cosmic variance. For galaxies brighter than M1500=-19.0, we derive a luminosity density ρ_UV= 1.5+2.0-0.9 × 1025 erg s-1 Hz^{-1 Mpc-3}, implying a decrease by a factor 3.5 from z=6 to z≃ 6.8. On the basis of our findings, we make predictions for the surface densities expected in future surveys, based on ULTRA-VISTA, HST-WFC3, or JWST-NIRCam, evaluating the best observational strategy to maximise their impact.

  4. Hawk-I Calibrations

    NASA Astrophysics Data System (ADS)

    Hibon, Pascale

    2017-09-01

    "The High Acuity Wide field K-band Imager (HAWK-I) instrument is a cryogenic wide field imager operating in the wavelength range 0.9 to 2.5 microns. It has been in operations since 2007 on the UT4 at the Very Large Telescope Observatory in seeing-limited mode. In 2017-2018, GRound Layer Adaptive optics Assisted by Lasers module (GRAAL) will be in operation and the system GRAAL+HAWK-I will be commissioned. With GRAAL, already installed, HAWK-I will operate more than 80% of the time with an equivalent K-band seeing of 0.55" (instead of 0.7" without GRAAL). I will present here an overview of the calibration plan for HAWK-I and GRAAL+HAWK-I and particularly the challenging aspects for optimal science products and instrument health monitoring."

  5. HAWK-I Takes Off

    NASA Astrophysics Data System (ADS)

    2007-08-01

    /VLT) HAWK-I takes images in the 0.9 to 2.5 micron domain over a large field-of-view of 7.5 x 7.5 arcminutes. This is nine times larger than that of ISAAC, another near-infrared imager on the VLT that went into operation in late 1998. ISAAC has shown how deep near-infrared images can contribute uniquely to the discovery and study of large, distant galaxies, and to the study of discs around stars or even very low mass objects, down to a few Jupiter masses. HAWK-I will build on this experience by being able to study much larger areas with an excellent image quality. HAWK-I has four 2k x 2k array detectors, i.e. a total of 16 million 0.1 arcsecond pixels. "Until the availability of the James Webb Space Telescope in the next decade, it is clear that 8-m class telescopes will provide the best sensitivity achievable in the near-infrared below 3 microns," explained Mark Casali, the ESO scientist responsible for the instrument. Given the wide field, fine sampling and the high sensitivity of HAWK-I, the deepest scientific impact is expected in the areas of faint sources. "With its special filter set, HAWK-I will allow us to peer into the most distant Universe," said Markus Kissler-Patig, the Instrument Scientist. "In particular, with HAWK-I, we will scrutinise the very first objects that formed in the Universe." HAWK-I will also be very well suited for the search for the most massive stars and for the least massive objects in our Galaxy, such as hot Jupiters. But HAWK-I will also be a perfect instrument for the study of outer Solar System bodies, such as distant, icy asteroids and comets. HAWK-I is the eleventh instrument to be installed at ESO's VLT. It bridges the gap between the first and the second generation instruments to be installed on this unique facility.

  6. VizieR Online Data Catalog: The Hawk-I UDS and GOODS Survey (HUGS) (Fontana+, 2014)

    NASA Astrophysics Data System (ADS)

    Fontana, A.; Dunlop, J. S.; Paris, D.; Targett, T. A.; Boutsia, K.; Castellano, M.; Galametz, A.; Grazian, A.; McLure, R.; Merlin, E.; Pentericci, L.; Wuyts, S.; Almaini, O.; Caputi, K.; Chary, R.-R.; Cirasuolo, M.; Conselice, C. J.; Cooray, A.; Daddi, E.; Dickinson, M.; Faber, S. M.; Fazio, G.; Ferguson, H. C.; Giallongo, E.; Giavalisco, M.; Grogin, N. A.; Hathi, N.; Koekemoer, A. M.; Koo, D. C.; Lucas, R. A.; Nonino, M.; Rix, H. W.; Renzini, A.; Rosario, D.; Santini, P.; Scarlata, C.; Sommariva, V.; Stark, D. P.; van der Wel, A.; Vanzella, E.; Wild, V.; Yan, H.; Zibetti, S.

    2014-10-01

    K-band galaxy number counts derived from the HUGS survey, corrected for incompleteness and other systematic effects as described in the text. Number densities are in units of galaxies per magnitude per square degree. Columns 2 and 3 assume unresolved morphologies for galaxies. Columns 4 and 5 assume a distributions of galaxy half-light radius from 0.1arcsec to 0.3arcsec. (1 data file).

  7. Performance updates of HAWK-I and preparation for the commissioning of the system GRAAL+HAWK-I

    NASA Astrophysics Data System (ADS)

    Hibon, Pascale; Paufique, Jerome; Kuntschner, Harald; Dobrzycka, Danuta; Le Louarn, Miska; Valenti, Elena; Neeser, Mark; Pompei, Emanuela; Arsenault, Robin; Siebenmorgen, Ralf; Madec, Pierre-Yves; Petr-Gotzens, Monika; La Fuente, Carlos; Urrutia, Josefina; Valenzuela, Javier; Castillo, Roberto; Baksai, Pedro; Garcia Dabo, Cesar Enrique; Jost, Andreas; Argomedo, Javier; Kolb, Johann; Kiekebusch, Mario; Hubin, Norbert; Duhoux, Philippe; Conzelmann, Ralf Dieter; Donaldson, Robert; Tordo, Sebastien; Huber, Stefan

    2016-08-01

    The High Acuity Wide field K-band Imager (HAWK-I) instrument is a cryogenic wide field imager operating in the wavelength range 0.9 to 2.5 microns. It has been in operations since 2007 on the UT4 at the Very Large Telescope Observatory in seeing-limited mode. In 2017-2018, GRound Layer Adaptive optics Assisted by Lasers module (GRAAL) will be in operation and the system GRAAL+HAWK-I will be commissioned. It will allow: deeper exposures for nearly point-source objects, or shorter exposure times for reaching the same magnitude, and/or deeper detection limiting magnitude. With GRAAL, HAWK-I will operate more than 80% of the time with an equivalent K-band seeing of 0.55" (instead of 0.7" without GRAAL). GRAAL is already installed and the operations without adaptive optics were commissioned in 2015. We discuss here the latest updates on performance from HAWK-I without Adaptive Optics (AO) and the preparation for the commissioning of the system GRAAL+HAWK-I.

  8. Deep Imaging Survey

    NASA Image and Video Library

    2003-07-25

    This is the first Deep Imaging Survey image taken by NASA Galaxy Evolution Explorer. On June 22 and 23, 2003, the spacecraft obtained this near ultraviolet image of the Groth region by adding multiple orbits for a total exposure time of 14,000 seconds. Tens of thousands of objects can be identified in this picture. http://photojournal.jpl.nasa.gov/catalog/PIA04627

  9. Search for Supernovae in Starburst Galaxies with HAWK-I

    NASA Astrophysics Data System (ADS)

    Miluzio, M.

    2014-03-01

    With the aim of testing the relation between supernova (SN) rate and star formation rate, we conducted a SN search in a sample of local starburst galaxies (SBs) where both star formation rates and extinction are extremely high. The search was performed in the near-infrared, where the bias due to extinction is reduced using HAWK-I on the VLT. We discovered six SNe, in excellent agreement with expectations, when considering that, even in our search, about 60% of events remain hidden in the nuclear regions due to a combination of reduced search efficiency and very high extinction.

  10. CANDELS MULTIWAVELENGTH CATALOGS: SOURCE IDENTIFICATION AND PHOTOMETRY IN THE CANDELS UKIDSS ULTRA-DEEP SURVEY FIELD

    SciTech Connect

    Galametz, Audrey; Grazian, Andrea; Fontana, Adriano; Castellano, Marco; Ferguson, Henry C.; Dahlen, Tomas; Grogin, Norman; Huang, Kuang-Han; Koekemoer, Anton M.; Ashby, M. L. N.; Willner, S. P.; Barro, Guillermo; Faber, Sandy M.; Guo, Yicheng; Kocevski, Dale D.; Lee, Kyoung-Soo; McGrath, Elizabeth J.; Peth, Michael; Almaini, Omar; Collaboration: CANDELS team; and others

    2013-06-01

    We present the multiwavelength-ultraviolet to mid-infrared-catalog of the UKIRT Infrared Deep Sky Survey (UKIDSS) Ultra-Deep Survey field observed as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). Based on publicly available data, the catalog includes the CANDELS data from the Hubble Space Telescope (near-infrared WFC3 F125W and F160W data and visible ACS F606W and F814W data); u-band data from CFHT/Megacam; B, V, R{sub c} , i', and z' band data from Subaru/Suprime-Cam; Y and K{sub s} band data from VLT/HAWK-I; J, H, and K band data from UKIDSS (Data Release 8); and Spitzer/IRAC data (3.6, 4.5 {mu}m from SEDS; 5.8 and 8.0 {mu}m from SpUDS). The present catalog is F160W-selected and contains 35, 932 sources over an area of 201.7 arcmin{sup 2} and includes radio- and X-ray-detected sources and spectroscopic redshifts available for 210 sources.

  11. CANDELS Multiwavelength Catalogs: Source Identification and Photometry in the CANDELS UKIDSS Ultra-deep Survey Field

    NASA Astrophysics Data System (ADS)

    Galametz, Audrey; Grazian, Andrea; Fontana, Adriano; Ferguson, Henry C.; Ashby, M. L. N.; Barro, Guillermo; Castellano, Marco; Dahlen, Tomas; Donley, Jennifer L.; Faber, Sandy M.; Grogin, Norman; Guo, Yicheng; Huang, Kuang-Han; Kocevski, Dale D.; Koekemoer, Anton M.; Lee, Kyoung-Soo; McGrath, Elizabeth J.; Peth, Michael; Willner, S. P.; Almaini, Omar; Cooper, Michael; Cooray, Asantha; Conselice, Christopher J.; Dickinson, Mark; Dunlop, James S.; Fazio, G. G.; Foucaud, Sebastien; Gardner, Jonathan P.; Giavalisco, Mauro; Hathi, N. P.; Hartley, Will G.; Koo, David C.; Lai, Kamson; de Mello, Duilia F.; McLure, Ross J.; Lucas, Ray A.; Paris, Diego; Pentericci, Laura; Santini, Paola; Simpson, Chris; Sommariva, Veronica; Targett, Thomas; Weiner, Benjamin J.; Wuyts, Stijn; the CANDELS Team

    2013-06-01

    We present the multiwavelength—ultraviolet to mid-infrared—catalog of the UKIRT Infrared Deep Sky Survey (UKIDSS) Ultra-Deep Survey field observed as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). Based on publicly available data, the catalog includes the CANDELS data from the Hubble Space Telescope (near-infrared WFC3 F125W and F160W data and visible ACS F606W and F814W data); u-band data from CFHT/Megacam; B, V, Rc , i', and z' band data from Subaru/Suprime-Cam; Y and Ks band data from VLT/HAWK-I; J, H, and K band data from UKIDSS (Data Release 8); and Spitzer/IRAC data (3.6, 4.5 μm from SEDS; 5.8 and 8.0 μm from SpUDS). The present catalog is F160W-selected and contains 35, 932 sources over an area of 201.7 arcmin2 and includes radio- and X-ray-detected sources and spectroscopic redshifts available for 210 sources.

  12. When VLT Meets HST: The HUGS Survey

    NASA Astrophysics Data System (ADS)

    Fontana, A.; Dunlop, J. S.; Paris, D.; Targett, T.; Boutsia, K.; Castellano, M.; Galametz, A.; Grazian, A.; McLure, R.; Merlin, E.; Pentericci, L.; Wuyts, S.; Almaini, O.; Caputi, K.; Chary, R.-R.; Cirasuolo, M.; Conselice, C.; Cooray, A.; Daddi, E.; Dickinson, M.; Faber, S. M.; Fazio, G.; Ferguson, H.; Giallongo, E.; Giavalisco, M.; Grogin, N.; Hathi, N.; Koekemoer, A.; Koo, D. C.; Lucas, R.; Nonino, M.; Rix, H.-W.; Renzini, A.; Rosario, D.; Santini, P.; Scarlata, C.; Sommariva, V.; Stark, D. P.; van der Wel, A.; Vanzella, E.; Wild, V.; Yan, H.; Zibetti, S.

    2014-03-01

    A new ultra-deep near-infrared imaging survey has been completed using the HAWK-I imager at the VLT. It is named HUGS (HAWK-I Ultra Deep Survey and GOODS Survey) and delivers the deepest, highest quality images ever collected in the K-band. HUGS complements the data delivered by the HST CANDELS survey over two well-studied extragalactic fields, and promises to open up exciting new opportunities to explore the highest redshift Universe. The survey is outlined and faint galaxy number counts and the search for passive galaxies in the early Universe are highlighted. The HUGS data have been completely analysed and are being made public to the worldwide community.

  13. The H-alpha luminosity function at redshift 2.2 . A new determination using VLT/HAWK-I

    NASA Astrophysics Data System (ADS)

    Hayes, M.; Schaerer, D.; Östlin, G.

    2010-01-01

    We aim to place new, strengthened constraints on the luminosity function (LF) of H-alpha (Hα) emitting galaxies at redshift z≈ 2.2, and to further constrain the instantaneous star-formation rate density of the universe (dotρstar). We have used the new HAWK-I instrument at ESO-VLT to obtain extremely deep narrow-band (line; NB2090) and broad-band (continuum; {K_s}) imaging observations. The target field is in the GOODS-South, providing us with a rich multi-wavelength auxiliary data set, which we utilise for redshift confirmation and to estimate dust content. We use this new data to measure the faint-end slope (α) of LF(Hα) with unprecedented precision. The data are well fit by a Schechter function and also a single power-law, yielding α = (-1.72± 0.20) and (-1.77± 0.21), respectively. Thus we are able to confirm the steepening of α from low- to high-z predicted by a number of authors and observed at other wavelengths. We combine our LF data-points with those from a much shallower but wider survey at z˜ 2.2 (Geach et al. 2008), constructing a LF spanning a factor of 50 in luminosity. Re-fitting the Schechter parameters, we obtain log L_star = (43.07± 0.22) erg s-1; log φ_star = (-3.45± 0.52) Mpc-3; α = (-1.60± 0.15). We integrate over LF(Hα) and apply a correction for dust attenuation to determine the instantaneous cosmic star-formation rate density at z˜ 2 without assuming α or extrapolating it from lower-z. Our measurement of dotρstar is (0.215± 0.090) M⊙ yr-1 Mpc-3, integrated over a range of 37≤ log (LHα /erg s-1)≤ 47. Based on observations made with ESO Telescopes at the Paranal Observatory under programme ID 081.A-0932.

  14. Deep wide-field near-infrared survey of the Carina Nebula

    NASA Astrophysics Data System (ADS)

    Preibisch, T.; Ratzka, T.; Kuderna, B.; Ohlendorf, H.; King, R. R.; Hodgkin, S.; Irwin, M.; Lewis, J. R.; McCaughrean, M. J.; Zinnecker, H.

    2011-06-01

    Context. The Great Nebula in Carina is a giant H ii region and a superb location in which to study the physics of violent massive star formation, but the population of the young low-mass stars remained very poorly studied until recently. Aims: Our aim was to produce a near-infrared survey that is deep enough to detect the full low-mass stellar population (i.e. down to ≈0.1 M⊙ and for extinctions up to AV ≈ 15 mag) and wide enough to cover all important parts of the Carina Nebula complex (CNC), including the clusters Tr 14, 15, and 16 as well as the South Pillars region. Methods: We used HAWK-I at the ESO VLT to survey the central ≈0.36 deg2 area of the Carina Nebula. These data reveal more than 600 000 individual infrared sources down to magnitudes as faint as J ≈ 23, H ≈ 22, and Ks ≈ 21. The results of a recent deep X-ray survey (which is complete down to stellar masses of ~0.5-1 M⊙) are used to distinguish between young stars in Carina and background contaminants. We analyze color - magnitude diagrams (CMDs) to derive information about the ages and masses of the low-mass stars. Results: The ages of the low-mass stars agree with previous age estimates for the massive stars. The CMD suggests that ≈3200 of the X-ray selected stars have masses of M∗ ≥ 1 M⊙; this number is in good agreement with extrapolations of the field IMF based on the number of high-mass (M∗ ≥ 20 M⊙) stars and shows that there is no deficit of low-mass stars in the CNC. The HAWK-I images confirm that about 50% of all young stars in Carina are in a widely distributed, non-clustered spatial configuration. Narrow-band images reveal six molecular hydrogen emission objects (MHOs) that trace jets from embedded protostars. However, none of the optical HH objects shows molecular hydrogen emission, suggesting that the jet-driving protostars are located very close to the edges of the globules in which they are embedded. Conclusions: The near-infrared excess fractions for the

  15. SXDF-UDS-CANDELS-ALMA 1.5 arcmin2 deep survey

    NASA Astrophysics Data System (ADS)

    Kohno, K.; Yamaguchi, Y.; Tamura, Y.; Tadaki, K.; Hatsukade, B.; Ikarashi, S.; Caputi, K. I.; Rujopakarn, W.; Ivison, R. J.; Dunlop, J. S.; Motohara, K.; Umehata, H.; Yabe, K.; Wang, W. H.; Kodama, T.; Koyama, Y.; Hayashi, M.; Matsuda, Y.; Hughes, D.; Aretxaga, I.; Wilson, G. W.; Yun, M. S.; Ohta, K.; Akiyama, M.; Kawabe, R.; Iono, D.; Nakanishi, K.; Lee, M.; Makiya, R.

    We have conducted 1.1 mm ALMA observations of a contiguous 105'' × 50'' or 1.5 arcmin2 window in the SXDF-UDS-CANDELS. We achieved a 5σ sensitivity of 0.28 mJy, giving a flat sensus of dusty star-forming galaxies with L IR ~6×1011 L ⊙ (if T dust=40K) up to z ~ 10 thanks to the negative K-correction at this wavelength. We detected 5 brightest sources (S/N>6) and 18 low-significant sources (5>S/N>4 they may contain spurious detections, though). One of the 5 brightest ALMA sources (S 1.1mm = 0.84 +/- 0.09 mJy) is extremely faint in the WFC3 and VLT/HAWK-I images, demonstrating that a contiguous ALMA imaging survey uncovers a faint dust-obscured population invisible in the deep optical/near-infrared surveys. We find a possible [CII]-line emitter at z=5.955 or a low-z CO emitting galaxy within the field, allowing us to constrain the [CII] and/or CO luminosity functions across the history of the universe.

  16. HAWK-I infrared supernova search in starburst galaxies

    NASA Astrophysics Data System (ADS)

    Miluzio, M.; Cappellaro, E.; Botticella, M. T.; Cresci, G.; Greggio, L.; Mannucci, F.; Benetti, S.; Bufano, F.; Elias-Rosa, N.; Pastorello, A.; Turatto, M.; Zampieri, L.

    2013-06-01

    Context. The use of SN rates to probe explosion scenarios and to trace the cosmic star formation history received a boost from a number of synoptic surveys. There has been a recent claim of a mismatch by a factor of two between star formation and core collapse SN rates, and different explanations have been proposed for this discrepancy. Aims: We attempted an independent test of the relation between star formation and supernova rates in the extreme environment of starburst galaxies, where both star formation and extinction are extremely high. Methods: To this aim we conducted an infrared supernova search in a sample of local starbursts galaxies. The rationale behind searching in the infrared is to reduce the bias due to extinction, which is one of the putative reasons for the observed discrepancy between star formation and supernova rates. To evaluate the outcome of the search we developed a MonteCarlo simulation tool that is used to predict the number and properties of the expected supernovae based on the search characteristics and the current understanding of starburst galaxies and supernovae. Results: During the search we discovered 6 supernovae (4 with spectroscopic classification), which is in excellent agreement with the prediction of the MonteCarlo simulation tool that is, on average, 5.3 ± 2.3 events. Conclusions: The number of supernovae detected in starburst galaxies is consistent with what is predicted from their high star formation rate when we recognize that a major fraction (~ 60%) of the events remain hidden in the inaccessible, high-density nuclear regions because of a combination of reduced search efficiency and high extinction. ESO proposal: 083.D-0259, 085.D-0335, 085.D-0348, 087.D-0494, 087.D-0922. GTC proposal: GTC50-11B.

  17. The ALFA ZOA Deep Survey: First Results

    NASA Astrophysics Data System (ADS)

    McIntyre, T. P.; Henning, P. A.; Minchin, R. F.; Momjian, E.; Butcher, Z.

    2015-07-01

    The Arecibo L-band Feed Array Zone of Avoidance (ALFA ZOA) Deep Survey is the deepest and most sensitive blind H i survey undertaken in the ZOA. ALFA ZOA Deep will cover about 300 square degrees of sky behind the Galactic Plane in both the inner (30^\\circ ≤slant l≤slant 75^\\circ ;b≤slant | 2^\\circ | ) and outer (175^\\circ ≤slant l≤slant 207^\\circ ;-2^\\circ ≤slant b≤slant +1^\\circ ) Galaxy, using the Arecibo Radio Telescope. First results from the survey have found 61 galaxies within a 15 square degree area centered on l=192^\\circ and b = -2°. The survey reached its expected sensitivity of rms = 1 mJy at 9 km s-1 channel resolution, and is shown to be complete above integrated flux, FHi = 0.5 Jy km s-1. The positional accuracy of the survey is 28″ and detections are found out to a recessional velocity of nearly 19,000 km s-1. The survey confirms the extent of the Orion and Abell 539 clusters behind the plane of the Milky Way and discovers expansive voids, at 10,000 and 18,000 km s-1. Twenty-six detections (43%) have a counterpart in the literature, but only two of these have known redshifts. Counterparts are 20% less common beyond vhel = 10,000 km s-1 and 33% less common at extinctions higher than AB = 3.5 mag. The ALFA ZOA Deep survey is able to probe large scale structure beyond redshifts that even the most modern wide-angle surveys have been able to detect in the ZOA at any wavelength.

  18. Science-Grade Imaging Data for HAWK-I, VIMOS, and VIRCAM: The ESO-UK Pipeline Collaboration

    NASA Astrophysics Data System (ADS)

    Neeser, M.; Lewis, J.; Madsen, G.; Yoldas, A.; Irwin, M.; Gabasch, A.; Coccato, L.; García-Dabó, C. E.; Romaniello, M.; Freudling, W.; Ballester, P.

    2016-12-01

    A new chapter for ESO science-grade data has begun with the implementa-tion of three new pipelines developed for the HAWK-I, VIMOS and VIRCAM instruments. The HAWK-I and VIMOS image archives at ESO have been completely reprocessed using these new pipelines, and these data are now publicly available. This article introduces the work done to bring these pipelines to the level of science-grade, their use in reprocessing ESO archival data, and their dissemination into ESO science operations and to the ESO community.

  19. Pan-STARRS-1 Medium Deep Survey

    NASA Astrophysics Data System (ADS)

    Huber, Mark

    2015-08-01

    The Panoramic Survey Telescope And Rapid Response System-1 (Pan-STARRS-1, PS1) has been in full science operation since Spring 2010 and concluded the observing program for the PS1 Science Consortium (PS1SC) in early 2014. The Medium Deep Survey (MDS) component of the program regularly visited 10 fields (~7 sq. deg. each) with significant multi-wavelength overlap from previous and concurrent surveys (e.g. SDSS, DEEP2, CDFS, COSMOS, GALEX) for 25% of the total time allocation. The cadence generally includes the g,r,i,z filters for a MDS field every 3 days over the 6-8 month season the field is visible, with the y filter done primarily during bright time. The nightly stacks of eight exposures typically reach depths of r,i~23.5 mag. Development work continued to improve the single exposure processing though to deep stacks during the transient event discovery and other science consortium programs over the course of the survey, the culmination of those improvements being applied in a more uniformly reprocessed dataset used for the public data release. A summary of the MDS public data release products will be presented.For details on PS1 and the Science Collaboration, visit http://ps1sc.org/

  20. DeepSurveyCam--A Deep Ocean Optical Mapping System.

    PubMed

    Kwasnitschka, Tom; Köser, Kevin; Sticklus, Jan; Rothenbeck, Marcel; Weiß, Tim; Wenzlaff, Emanuel; Schoening, Timm; Triebe, Lars; Steinführer, Anja; Devey, Colin; Greinert, Jens

    2016-01-28

    Underwater photogrammetry and in particular systematic visual surveys of the deep sea are by far less developed than similar techniques on land or in space. The main challenges are the rough conditions with extremely high pressure, the accessibility of target areas (container and ship deployment of robust sensors, then diving for hours to the ocean floor), and the limitations of localization technologies (no GPS). The absence of natural light complicates energy budget considerations for deep diving flash-equipped drones. Refraction effects influence geometric image formation considerations with respect to field of view and focus, while attenuation and scattering degrade the radiometric image quality and limit the effective visibility. As an improvement on the stated issues, we present an AUV-based optical system intended for autonomous visual mapping of large areas of the seafloor (square kilometers) in up to 6000 m water depth. We compare it to existing systems and discuss tradeoffs such as resolution vs. mapped area and show results from a recent deployment with 90,000 mapped square meters of deep ocean floor.

  1. DeepSurveyCam—A Deep Ocean Optical Mapping System

    PubMed Central

    Kwasnitschka, Tom; Köser, Kevin; Sticklus, Jan; Rothenbeck, Marcel; Weiß, Tim; Wenzlaff, Emanuel; Schoening, Timm; Triebe, Lars; Steinführer, Anja; Devey, Colin; Greinert, Jens

    2016-01-01

    Underwater photogrammetry and in particular systematic visual surveys of the deep sea are by far less developed than similar techniques on land or in space. The main challenges are the rough conditions with extremely high pressure, the accessibility of target areas (container and ship deployment of robust sensors, then diving for hours to the ocean floor), and the limitations of localization technologies (no GPS). The absence of natural light complicates energy budget considerations for deep diving flash-equipped drones. Refraction effects influence geometric image formation considerations with respect to field of view and focus, while attenuation and scattering degrade the radiometric image quality and limit the effective visibility. As an improvement on the stated issues, we present an AUV-based optical system intended for autonomous visual mapping of large areas of the seafloor (square kilometers) in up to 6000 m water depth. We compare it to existing systems and discuss tradeoffs such as resolution vs. mapped area and show results from a recent deployment with 90,000 mapped square meters of deep ocean floor. PMID:26828495

  2. THE SPITZER DEEP, WIDE-FIELD SURVEY

    SciTech Connect

    Ashby, M. L. N.; Brodwin, M.; Stern, D.; Griffith, R.; Eisenhardt, P.; Gorjian, V.; Kozlowski, S.; Kochanek, C. S.; Bock, J. J.; Borys, C.; Brand, K.; Grogin, N. A.; Brown, M. J. I.; Cool, R.; Cooray, A.; Croft, S.; Dey, A.; Eisenstein, D.; Gonzalez, A. H.; Ivison, R. J.

    2009-08-10

    The Spitzer Deep, Wide-Field Survey (SDWFS) is a four-epoch infrared survey of 10 deg.{sup 2} in the Booetes field of the NOAO Deep Wide-Field Survey using the IRAC instrument on the Spitzer Space Telescope. SDWFS, a Spitzer Cycle 4 Legacy project, occupies a unique position in the area-depth survey space defined by other Spitzer surveys. The four epochs that make up SDWFS permit-for the first time-the selection of infrared-variable and high proper motion objects over a wide field on timescales of years. Because of its large survey volume, SDWFS is sensitive to galaxies out to z {approx} 3 with relatively little impact from cosmic variance for all but the richest systems. The SDWFS data sets will thus be especially useful for characterizing galaxy evolution beyond z {approx} 1.5. This paper explains the SDWFS observing strategy and data processing, presents the SDWFS mosaics and source catalogs, and discusses some early scientific findings. The publicly released, full-depth catalogs contain 6.78, 5.23, 1.20, and 0.96 x 10{sup 5} distinct sources detected to the average 5{sigma}, 4''-diameter, aperture-corrected limits of 19.77, 18.83, 16.50, and 15.82 Vega mag at 3.6, 4.5, 5.8, and 8.0 {mu}m, respectively. The SDWFS number counts and color-color distribution are consistent with other, earlier Spitzer surveys. At the 6 minute integration time of the SDWFS IRAC imaging, >50% of isolated Faint Images of the Radio Sky at Twenty cm radio sources and >80% of on-axis XBooetes sources are detected out to 8.0 {mu}m. Finally, we present the four highest proper motion IRAC-selected sources identified from the multi-epoch imaging, two of which are likely field brown dwarfs of mid-T spectral class.

  3. Pan-STARRS1 Medium Deep Survey

    NASA Astrophysics Data System (ADS)

    Huber, Mark; PS1 Science Consortium; Pan-STARRS IPP Team

    2017-01-01

    The Panoramic Survey Telescope And Rapid Response System 1 (Pan-STARRS1, PS1) has been in full science operation since Spring 2010 with the PS1 Science Consortium (PS1SC) observational program concluding in early 2014. The Medium Deep Survey (MDS) component of the program, allocated 25% of the time, regularly visited 10 fields (~7 sq. deg. each) with significant multi-wavelength overlap from previous and concurrent surveys (e.g. SDSS, DEEP2, CDFS, COSMOS, GALEX). The cadence generally includes the g & r, i, z filters in a 3 day cycle with nightly 5-sigma point source stack depths of r,i~23.5 mag and switching to the y filter primarily during bright time over the 6-8 month season a MDS field is visible. While nightly processing was regularly producing data for the transient event discovery and other science consortium programs with incremental improvements during the survey, the entire MDS dataset has now been uniformly reprocessed for the upcoming public data release. The MDS data products, to be made available after the full release of the 3PI dataset, will be summarily presented.For details on PS1 and the Science Consortium, visit http://ps1sc.org/

  4. Deep Surveys of Obscured Active Galactic Nuclei

    NASA Astrophysics Data System (ADS)

    Chatzichristou, Eleni T.

    2006-08-01

    Several key goals require measuring the number of all Active Galactic Nuclei (AGN) in the Universe, and the evolution of the ratio of obscured to unobscured AGN with redshift. This reflects the structure of AGN and thus the development in the heart of all galaxies. Hard X-rays can penetrate most obscuring dust columns to reveal the AGN that remains hidden in all other wavelengths. Mid-IR surveys probe the thermal dust emission, that is, the continuum light from the central source after it is reprocessed by dust, and this emission dominates the bolometric luminosities of dusty high-redshift galaxies. Thus, combining deep mid-IR and hard X-ray surveys can provide us with accurate demographics of AGN especially at high redshifts. Multi-wavelength surveys aim to address these science goals by exploiting the unprecedented combination of great observatories such as HST, Chandra and SIRTF to survey the distant universe to the faintest flux limits across the broadest range of wavelengths. In this paper I discuss some of the results coming from multi-wavelength surveys placing particular focus on the systematic study of obscured AGN.

  5. The UV Luminosity Function of z˜ 7 galaxies from wide and deep HST and ESO/VLT surveys

    NASA Astrophysics Data System (ADS)

    Grazian, A.; Pentericci, L.; Castellano, M.; Fontana, A.

    The study of the Luminosity Function (LF) of Lyman Break Galaxies (LBGs) at z=7 is very important for ascertaining their role in the reionization of the Universe. In this work we plan to perform a robust determination of the UV LF for LBGs at z˜ 7. To this aim, we have assembled a large sample of candidate LBGs at z˜ 7 from different surveys, spanning a large variety of areas and depths. In particular, we have combined data from the deep (J<27.4) and ultradeep (J<29.2) surveys recently acquired with the new WFC3 NIR camera on HST, over the GOODS-ERS (˜40 sq. arcmin.) and the HUDF (˜4 sq. arcmin.) fields, with a ground based survey in wide and relatively shallow areas (˜200 sq. arcmin.) from Hawk-I@VLT. We have used public images in the z band to select z-dropout galaxies, and other public data both in the blue (UBVRI) and in the red bands to reject possible low-redshift interlopers. We have found that the number density of faint LBGs at z˜ 7 is strongly dependent on the assumption made on the half light distributions of the simulated galaxies, used to correct the observed sample for incompleteness. We conclude that galaxies at z˜ 7 are unable to reionize the Universe unless there is a significant evolution in the clumpiness of the inter-galactic medium (IGM) or in the escape fraction of ionising photons or, alternatively, there is a large population of z˜ 7 LBGs with large physical dimensions but still not detected by the present observations.

  6. SEDS: The Spitzer Extended Deep Survey. Survey Design, Photometry, and Deep IRAC Source Counts

    NASA Technical Reports Server (NTRS)

    Ashby, M. L. N.; Willner, S. P.; Fazio, G. G.; Huang, J.-S.; Arendt, A.; Barmby, P.; Barro, G; Bell, E. F.; Bouwens, R.; Cattaneo, A.; hide

    2013-01-01

    The Spitzer Extended Deep Survey (SEDS) is a very deep infrared survey within five well-known extragalactic science fields: the UKIDSS Ultra-Deep Survey, the Extended Chandra Deep Field South, COSMOS, the Hubble Deep Field North, and the Extended Groth Strip. SEDS covers a total area of 1.46 deg(exp 2) to a depth of 26 AB mag (3sigma) in both of the warm Infrared Array Camera (IRAC) bands at 3.6 and 4.5 micron. Because of its uniform depth of coverage in so many widely-separated fields, SEDS is subject to roughly 25% smaller errors due to cosmic variance than a single-field survey of the same size. SEDS was designed to detect and characterize galaxies from intermediate to high redshifts (z = 2-7) with a built-in means of assessing the impact of cosmic variance on the individual fields. Because the full SEDS depth was accumulated in at least three separate visits to each field, typically with six-month intervals between visits, SEDS also furnishes an opportunity to assess the infrared variability of faint objects. This paper describes the SEDS survey design, processing, and publicly-available data products. Deep IRAC counts for the more than 300,000 galaxies detected by SEDS are consistent with models based on known galaxy populations. Discrete IRAC sources contribute 5.6 +/- 1.0 and 4.4 +/- 0.8 nW / square m/sr at 3.6 and 4.5 micron to the diffuse cosmic infrared background (CIB). IRAC sources cannot contribute more than half of the total CIB flux estimated from DIRBE data. Barring an unexpected error in the DIRBE flux estimates, half the CIB flux must therefore come from a diffuse component.

  7. SEDS: THE SPITZER EXTENDED DEEP SURVEY. SURVEY DESIGN, PHOTOMETRY, AND DEEP IRAC SOURCE COUNTS

    SciTech Connect

    Ashby, M. L. N.; Willner, S. P.; Fazio, G. G.; Huang, J.-S.; Hernquist, L.; Hora, J. L.; Arendt, R.; Barmby, P.; Barro, G.; Faber, S.; Guhathakurta, P.; Bouwens, R.; Cattaneo, A.; Croton, D.; Dave, R.; Dunlop, J. S.; Egami, E.; Finlator, K.; Grogin, N. A.; and others

    2013-05-20

    The Spitzer Extended Deep Survey (SEDS) is a very deep infrared survey within five well-known extragalactic science fields: the UKIDSS Ultra-Deep Survey, the Extended Chandra Deep Field South, COSMOS, the Hubble Deep Field North, and the Extended Groth Strip. SEDS covers a total area of 1.46 deg{sup 2} to a depth of 26 AB mag (3{sigma}) in both of the warm Infrared Array Camera (IRAC) bands at 3.6 and 4.5 {mu}m. Because of its uniform depth of coverage in so many widely-separated fields, SEDS is subject to roughly 25% smaller errors due to cosmic variance than a single-field survey of the same size. SEDS was designed to detect and characterize galaxies from intermediate to high redshifts (z = 2-7) with a built-in means of assessing the impact of cosmic variance on the individual fields. Because the full SEDS depth was accumulated in at least three separate visits to each field, typically with six-month intervals between visits, SEDS also furnishes an opportunity to assess the infrared variability of faint objects. This paper describes the SEDS survey design, processing, and publicly-available data products. Deep IRAC counts for the more than 300,000 galaxies detected by SEDS are consistent with models based on known galaxy populations. Discrete IRAC sources contribute 5.6 {+-} 1.0 and 4.4 {+-} 0.8 nW m{sup -2} sr{sup -1} at 3.6 and 4.5 {mu}m to the diffuse cosmic infrared background (CIB). IRAC sources cannot contribute more than half of the total CIB flux estimated from DIRBE data. Barring an unexpected error in the DIRBE flux estimates, half the CIB flux must therefore come from a diffuse component.

  8. The BMW Deep X-Ray Cluster Survey

    NASA Astrophysics Data System (ADS)

    Guzzo, Luigi; Moretti, Alberto; Campana, Sergio; Covino, Stefano; Dell'Antonio, Ian; Lazzati, Davide; Longhetti, Marcella; Molinari, Emilio; Panzera, Maria Rosa; Tagliaferri, Gianpiero

    We briely describe the main features and first results of the BMW survey of serendipitous X-ray clusters, based on the still unexploited ROSAT-HRI archival observations. The sky coverage, surface density and first deep CCD images of the candidates indicate that this sample can represent an excellent complement to the existing PSPC deep cluster surveys.

  9. The Gemini Deep Planet Survey - GDPS

    SciTech Connect

    Lafreniere, D; Doyon, R; Marois, C; Nadeau, D; Oppenheimer, B R; Roche, P F; Rigaut, F; Graham, J R; Jayawardhana, R; Johnstone, D; Kalas, P G; Macintosh, B; Racine, R

    2007-06-01

    We present the results of the Gemini Deep Planet Survey, a near-infrared adaptive optics search for giant planets and brown dwarfs around nearby young stars. The observations were obtained with the Altair adaptive optics system at the Gemini North telescope and angular differential imaging was used to suppress the speckle noise of the central star. Detection limits for the 85 stars observed are presented, along with a list of all faint point sources detected around them. Typically, the observations are sensitive to angular separations beyond 0.5-inch with 5{sigma} contrast sensitivities in magnitude difference at 1.6 {micro}m of 9.6 at 0.5-inch, 12.9 at 1-inch, 15 at 2-inch, and 16.6 at 5-inch. For the typical target of the survey, a 100 Myr old K0 star located 22 pc from the Sun, the observations are sensitive enough to detect planets more massive than 2 M{sub Jup} with a projected separation in the range 40-200 AU. Depending on the age, spectral type, and distance of the target stars, the minimum mass that could be detected with our observations can be {approx}1 M{sub Jup}. Second epoch observations of 48 stars with candidates (out of 54) have confirmed that all candidates are unrelated background stars. A detailed statistical analysis of the survey results, which provide upper limits on the fractions of stars with giant planet or low mass brown dwarf companions, is presented. Assuming a planet mass distribution dn/dm {proportional_to} m{sup -1.2} and a semi-major axis distribution dn/da {proportional_to} a{sup -1}, the upper limits on the fraction of stars with at least one planet of mass 0.5-13 M{sub Jup} are 0.29 for the range 10-25 AU, 0.13 for 25-50 AU, and 0.09 for 50-250 AU, with a 95% confidence level; this result is weakly dependent on the semi-major axis distribution power-law index. Without making any assumption on the mass and semi-major axis distributions, the fraction of stars with at least one brown dwarf companion having a semi-major axis in the

  10. Deep Surveys for Inner Oort Cloud Objects

    NASA Astrophysics Data System (ADS)

    Trujillo, Chadwick A.; Tholen, David J.; Sheppard, Scott S.

    2015-11-01

    We are undertaking two deep wide-field surveys to discover extremely distant solar system objects. While our target solar system population is the Inner Oort Cloud objects such as 2012 VP113 and Sedna, we are also sensitive to other populations with high perihelia such as the Scattered Kuiper Belt Objects and the highest perihelion Kuiper Belt Objects which have similar arguments of perihelion to the Inner Oort Cloud Objects. These unusual populations are thought to consist primarily of highly eccentric objects which spend most of their orbits hundreds or thousands of AU from the sun. Large aperture telescopes are needed to reach the faintness limits, red magnitudes of 23.5 to 25, required for detection of even the large members of the population. In addition, wide fields of view are also needed since the sky density of the detectable members of the populations approach 1 in 100 square degrees even with large telescopes.Our primary discovery instruments are the Dark Energy Camera (DECam) on the 4 meter Blanco Telescope at the Cerro Tololo Inter-American Observatory and Hyper Suprime-Cam (HSC) on Subaru Telescope at Maunakea. Each of these instruments has a tremendously wide field of view considering the size of the telescope they are mounted on. DECam has a field of view of about 3 square degrees and HSC has a field of view of about 1.75 square degrees. We will present our survey progress in terms of sky area covered and new objects discovered and highlight some of our more interesting findings.

  11. Ground-based astrometry with wide field imagers. V. Application to near-infrared detectors: HAWK-I@VLT/ESO

    NASA Astrophysics Data System (ADS)

    Libralato, M.; Bellini, A.; Bedin, L. R.; Piotto, G.; Platais, I.; Kissler-Patig, M.; Milone, A. P.

    2014-03-01

    High-precision astrometry requires accurate point-spread function modeling and accurate geometric-distortion corrections. This paper demonstrates that it is possible to achieve both requirements with data collected at the high acuity wide-field K-band imager (HAWK-I), a wide-field imager installed at the Nasmyth focus of UT4/VLT ESO 8 m telescope. Our final astrometric precision reaches ~3 mas per coordinate for a well-exposed star in a single image with a systematic error less than 0.1 mas. We constructed calibrated astro-photometric catalogs and atlases of seven fields: the Baade's window, NGC 6656, NGC 6121, NGC 6822, NGC 6388, NGC 104, and the James Webb Space Telescope calibration field (in the Large Magellanic Cloud). We make these catalogs and images electronically available to the community. Furthermore, as a demonstration of the efficacy of our approach, we combined archival material taken with the optical wide-field imager at the MPI/ESO 2.2 m with HAWK-I observations. We showed that we are able to achieve an excellent separation between cluster members and field objects for NGC 6656 and NGC 6121 with a time base-line of about 8 years. Using both HST and HAWK-I data, we also study the radial distribution of the SGB populations in NGC 6656 and conclude that the radial trend is flat within our uncertainty. We also provide membership probabilities for most of the stars in NGC 6656 and NGC 6121 catalogs and estimate membership for the published variable stars in these two fields. Catalogs, fortran code, and distortion maps are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/563/A80Based on observations with the 8 m VLT ESO telescope.

  12. VizieR Online Data Catalog: A 1689 HAWK-I J-band image (Petrushevska+, 2016)

    NASA Astrophysics Data System (ADS)

    Petrushevska, T.; Amanullah, R.; Goobar, A.; Fabbro, S.; Johansson, J.; Kjellsson, T.; Lidman, C.; Paech, K.; Richard, J.; Dahle, H.; Ferretti, R.; Kneib, J. P.; Limousin, M.; Nordin, J.; Stanishev, V.

    2016-10-01

    The NIR data were obtained with the High Acuity Wide field K-band imager mounted on the VLT (Programmes ID 082.A-0431, 0.83.A-0398, 090.A-0492, 091.A-0108, P.I. Goobar). The HAWK-I has an array of four 2048x2048 HgCdTe detectors covering a total area of 7.5'x7.5' with a sampling of 0.106"/pix per pixel. The chips are separated by a 15" gap. (2 data files).

  13. Revised Supernova Rates from the IfA Deep Survey

    NASA Astrophysics Data System (ADS)

    Rodney, Steven A.; Tonry, John L.

    2010-11-01

    The IfA Deep Survey uncovered ~ 130 thermonuclear supernova (TN SN, i.e., Type Ia) candidates at redshifts from z = 0.1 out to beyond z = 1. The TN SN explosion rates derived from these data have been controversial, conflicting with evidence emerging from other surveys. This work revisits the IfA Deep Survey to re-evaluate the photometric evidence. Applying the SOFT program to the light curves of all SN candidates, we derive new classification grades and redshift estimates. We find a volumetric rate for z ~ 0.5 that is substantially smaller than the originally published values, bringing the revised IfA Deep rate into good agreement with other surveys. With our improved photometric analysis techniques, we are able to confidently extend the rate measurements to higher redshifts and we find a steadily increasing TN SN rate, with no indication of a peak out to z = 1.05.

  14. A very deep IRAS survey at the north ecliptic pole

    NASA Technical Reports Server (NTRS)

    Houck, J. R.; Hacking, P. B.; Condon, J. J.

    1987-01-01

    The data from approximately 20 hours observation of the 4- to 6-square degree field surrounding the north ecliptic pole have been combined to produce a very deep IR survey at the four IRAS bands. Scans from both pointed and survey observations were included in the data analysis. At 12 and 25 microns the deep survey is limited by detector noise and is approximately 50 times deeper than the IRAS Point Source Catalog (PSC). At 60 microns the problems of source confusion and Galactic cirrus combine to limit the deep survey to approximately 12 times deeper than the PSC. These problems are so severe at 100 microns that flux values are only given for locations corresponding to sources selected at 60 microns. In all, 47 sources were detected at 12 microns, 37 at 25 microns, and 99 at 60 microns. The data-analysis procedures and the significance of the 12- and 60-micron source-count results are discussed.

  15. SXDF-UDS-CANDELS-ALMA 1.5 arcmin2 deep survey

    NASA Astrophysics Data System (ADS)

    Kohno, Kotaro; Tamura, Yoichi; Yamaguchi, Yuki; Umehata, Hideki; Rujopakarn, Wiphu; Lee, Minju; Motohara, Kentaro; Makiya, Ryu; Izumi, Takuma; Ivison, Rob; Ikarashi, Soh; Tadaki, Ken-ichi; Kodama, Tadayuki; Hatsukade, Bunyo; Yabe, Kiyoto; Hayashi, Masao; Iono, Daisuke; Matsuda, Yuichi; Nakanishi, Kouichiro; Kawabe, Ryohei; Wilson, Grant; Yun, Min S.; Hughes, David; Caputi, Karina; Dunlop, James

    2015-08-01

    We have conducted 1.1 mm ALMA observations of a contiguous 105″ × 50″ or 1.5 arcmin2 window (achieved by 19 point mosaic) in the SXDF-UDS-CANDELS. We achieved a 5σ sensitivity of 0.28 mJy, giving a flat sensus of dusty star-forming galaxies with LIR ~6 × 1011 L⊙ (if Tdust = 40 K) or SFR ~100 M⊙ yr-1 up to z~10 thanks to the negative K-correction at this wavelength. We detect 5 brightest sources (S/N>6) and 18 low-significant sources (5 > S/N > 4; they may contain spurious detections, though) in the field. We find that these discrete sources are responsible for a faint filamentary emission seen in low-resolution (~30″) heavily confused AzTEC 1.1mm and SPIRE 0.5mm images. One of the 5 brightest ALMA sources is very dark in deep WFC3 and HAWK-I NIR images as well as VLA 1.4 GHz images, demonstrating that deep ALMA imaging can unveil new obscured star-forming galaxy population.

  16. The variable sky of deep synoptic surveys

    SciTech Connect

    Ridgway, Stephen T.; Matheson, Thomas; Mighell, Kenneth J.; Olsen, Knut A.; Howell, Steve B.

    2014-11-20

    The discovery of variable and transient sources is an essential product of synoptic surveys. The alert stream will require filtering for personalized criteria—a process managed by a functionality commonly described as a Broker. In order to understand quantitatively the magnitude of the alert generation and Broker tasks, we have undertaken an analysis of the most numerous types of variable targets in the sky—Galactic stars, quasi-stellar objects (QSOs), active galactic nuclei (AGNs), and asteroids. It is found that the Large Synoptic Survey Telescope (LSST) will be capable of discovering ∼10{sup 5} high latitude (|b| > 20°) variable stars per night at the beginning of the survey. (The corresponding number for |b| < 20° is orders of magnitude larger, but subject to caveats concerning extinction and crowding.) However, the number of new discoveries may well drop below 100 per night within less than one year. The same analysis applied to GAIA clarifies the complementarity of the GAIA and LSST surveys. Discovery of AGNs and QSOs are each predicted to begin at ∼3000 per night and decrease by 50 times over four years. Supernovae are expected at ∼1100 per night, and after several survey years will dominate the new variable discovery rate. LSST asteroid discoveries will start at >10{sup 5} per night, and if orbital determination has a 50% success rate per epoch, they will drop below 1000 per night within two years.

  17. The Swift/XRT Deep Galactic Plane Survey

    NASA Astrophysics Data System (ADS)

    Gorgone, Nicholas; Kouveliotou, Chryssa

    2017-08-01

    The Swift Deep Galactic Plane Survey utilizes XRT (0.3-10 keV) in the first deep, homogeneous and systematic search for magnetars, HMXBs, and transients. Over two years we will survey 40 sq. deg., in the two regions where the Galactic bar meets the Scutum and Perseus Arms (10 deg < |l|< 30deg and |b| < 0.5 deg) in 366 overlapping 5ks tiles. The survey will be complete to luminosities of L=1.0x1034 erg s-1 and relies on multi-wavelength archival and follow up data to determine the nature of new sources as well as spectral and temporal variability. The goal of this survey is to better establish the source populations of compact stellar systems by increasing their numbers for statistical studies. We will also constrain the galactic star formation rate and the nature of massive star evolution. Here we present first results from the survey.

  18. The BMW Deep X-ray Cluster Survey

    NASA Astrophysics Data System (ADS)

    Moretti, A.; Guzzo, L.; Campana, S.; Covino, S.; Lazzati, D.; Longhetti, M.; Molinari, E.; Panzera, M. R.; Tagliaferri, G.; dell'Antonio, I.

    We describe the main features of the BMW survey of serendipitous X-ray clusters, based on the still unexploited ROSAT-HRI archival observations. The sky coverage, surface density and first deep optical CCD images of the candidates indicate that this sample can represent an excellent complement to the existing PSPC deep cluster surveys and will provide us with a fully independent probe of the evolution of the cluster abundance, in addition to significantly increasing the number of clusters known at z>0.6.

  19. A Deep Optical Survey of the Ecliptic

    NASA Technical Reports Server (NTRS)

    Jewitt, David

    1997-01-01

    This was an observing-intensive investigation into the newly discovered regions of the solar system beyond Neptune. The research was focussed on the use of unique imaging facilities on telescopes atop Mauna Kea, Hawaii, although other observatories (in Arizona and Chile) were also occasionally used. We secured about 20 nights of telescope time per year for our 'Medium Depth Wide Area' survey (JLC96). In this, we covered 5 sq. deg. of sky to apparent red magnitude 24.2. We used a high quantum efficiency Tektronix 2048x2048 CCD for all observations in this program. We secured observing time at the UH 2.2 meter for testing the suitability of a much larger array CCD camera for survey work (an 8192x8192 pixel device). We obtained observing runs at the twin Schmidt telescopes of Kitt Peak National Observatory and Cerro-Tololo InterAmerican Observatory in order to assess the number of bright Kuiper Belt objects, Centaurs and gas giant Trojans.

  20. Initial results from a ROSAT deep survey in Lynx

    NASA Technical Reports Server (NTRS)

    Anderson, S. F.; Windhorst, R. A.; Maccacaro, T.; Burstein, D.; Franklin, B. E.; Griffiths, R. E.; Koo, D. C.; Mathis, D. F.; Morgan, W. A.; Neuschaefer, L. W.

    1992-01-01

    Preliminary results from a deep (70 ksec) Rosat survey of the high galactic latitude selected area Lynx.3A are presented. Lynx.3A sensitivity was previously studied in both the optical radio, with deep Westerbork surveys and deep multicolor Charge Couple Device (CCD) images form the Palomar 200 inch Four-Shooter. About 70 x-ray sources were detected within the central 40 foot diameter region of the Position Sensitive Proportional Counter (PSPC), observed surface densities of approximately 200 x-ray sources/sq deg are suggested, and these x-ray sources alone account for approximately 30 percent of the cosmic x-ray background (0.9 to 2.2 keV). An initial look at the observed x-ray logN - logS curve is presented, but a detailed assessment requires further study. The 4 sigma limit of about 7 times 10 to the minus 15th power erg/s.sq cm (0.5 to 2.0 keV) is considerably deeper then the Einstein deep surveys, and of comparable sensitivity to the deepest current Rosat surveys. Cross correlation with our Four Shooter optical catalogs yields at least one likely optical candidate for nearly all of the Rosat x-ray sources; a number of the likely optical identifications have colors of quasi-stellar objects (and stellar PSF), but in other cases galaxies/groups are also viable candidates.

  1. Initial results from a ROSAT deep survey in Lynx

    NASA Technical Reports Server (NTRS)

    Anderson, S. F.; Windhorst, R. A.; Maccacaro, T.; Burstein, D.; Franklin, B. E.; Griffiths, R. E.; Koo, D. C.; Mathis, D. F.; Morgan, W. A.; Neuschaefer, L. W.

    1992-01-01

    Preliminary results from a deep (70 ksec) Rosat survey of the high galactic latitude selected area Lynx.3A are presented. Lynx.3A sensitivity was previously studied in both the optical radio, with deep Westerbork surveys and deep multicolor Charge Couple Device (CCD) images form the Palomar 200 inch Four-Shooter. About 70 x-ray sources were detected within the central 40 foot diameter region of the Position Sensitive Proportional Counter (PSPC), observed surface densities of approximately 200 x-ray sources/sq deg are suggested, and these x-ray sources alone account for approximately 30 percent of the cosmic x-ray background (0.9 to 2.2 keV). An initial look at the observed x-ray logN - logS curve is presented, but a detailed assessment requires further study. The 4 sigma limit of about 7 times 10 to the minus 15th power erg/s.sq cm (0.5 to 2.0 keV) is considerably deeper then the Einstein deep surveys, and of comparable sensitivity to the deepest current Rosat surveys. Cross correlation with our Four Shooter optical catalogs yields at least one likely optical candidate for nearly all of the Rosat x-ray sources; a number of the likely optical identifications have colors of quasi-stellar objects (and stellar PSF), but in other cases galaxies/groups are also viable candidates.

  2. The Deep Interferometric VSOP--Arecibo Survey (DIVAS)

    NASA Astrophysics Data System (ADS)

    Edwards, P. G.; Hirabayashi, H.; Ulvestad, J. S.; Salter, C.; Ghosh, T.; Gurvits, L. I.; Fomalont, E. B.

    2009-08-01

    The Deep Interferometric VSOP-Arecibo Survey (DIVAS) program used space VLBI observations of a faint sample of flat-spectrum sources made with the HALCA satellite and the Arecibo telescope to provide the highest possible space VLBI sensitivity at 5 GHz. The main aim of the survey is to compare statistical results on the source structures (e.g., brightness temperatures, sizes, visibilities) with results from the VLBI Space Observatory Programme (VSOP) Survey, to determine whether there are systematic differences in the compact structures of sources selected from samples with limiting flux densities differing by over an order of magnitude.

  3. PRIME: A Deep Near-infrared Survey Mission Concept

    NASA Astrophysics Data System (ADS)

    Zheng, W.; Ford, H. C.; Davidsen, A. F.; Kruk, J. W.; Tsvetanov, Z. I.; Szalay, A. S.; Hartig, G.; Postman, M.; Stockman, H. S.; Thompson, R.; Shu, P. K.; Lenzen, R.; Rix, H.-W.; Mark, D.; McGuffey, D.

    2000-12-01

    PRIME (The Primordial Explorer) is a proposed mission that has been selected for NASA SMEX concept study. It will carry out a deep sky survey from space in four near-infrared bands between 0.9-3.5 micron. The 0.75m telescope will survey a quarter of the sky to AB magnitude of approximately 24 in 1.5 years. Deeper surveys in selected sky regions are also planned. PRIME will reach an epoch during which the first quasars, galaxies and clusters of galaxies were formed in the early Universe, discover hundreds of Type-Ia supernovae to be used in measuring the acceleration of the expanding Universe, and detect hundreds of brown dwarfs and even Jupiter-size planets in the vicinity of the solar system. Most of these objects are so rare that they may be identified only in large and deep surveys. PRIME will serve as a pilot mission for the Next Generation Space Telescope (NGST) supplying rare targets for NGST spectroscopy and deep imaging. Combining PRIME with other surveys (SDSS, GALEX) will yield the largest astronomical database ever built.

  4. MOIRCS Deep Survey. IX. Deep Near-Infrared Imaging Data and Source Catalog

    NASA Astrophysics Data System (ADS)

    Kajisawa, Masaru; Ichikawa, Takashi; Tanaka, Ichi; Yamada, Toru; Akiyama, Masayuki; Suzuki, Ryuji; Tokoku, Chihiro; Katsuno Uchimoto, Yuka; Konishi, Masahiro; Yoshikawa, Tomohiro; Nishimura, Tetsuo; Omata, Koji; Ouchi, Masami; Iwata, Ikuru; Hamana, Takashi; Onodera, Masato

    2011-03-01

    We present deep J-, H-, and Ks-band imaging data of the MOIRCS Deep Survey (MODS), which was carried out with the Multi-Object Infrared Camera and Spectrograph (MOIRCS) mounted on the Subaru Telescope in the GOODS-North region. The data reach 5σ total limiting magnitudes for point sources of J = 23.9, H = 22.8, and Ks = 22.8 (Vega magnitude) over 103 arcmin2 (wide field). In 28 arcmin2 of the survey area, which is an ultra-deep field of the MODS (deep field), the data reach 5σ depths of J = 24.8, H = 23.4, and Ks = 23.8. The spatial resolutions of the combined images are FWHM ˜0''.6 and ˜0''.5 for the wide and deep fields in all bands, respectively. Combining the MODS data with the multi-wavelength public data taken with the HST, Spitzer, and other ground-based telescopes in the GOODS field, we constructed a multi-wavelength photometric catalog of Ks-selected sources. Using the catalog, we present Ks-band number counts and near-infrared color distribution of the detected objects; we also demonstrate some selection techniques with the NIR colors for high redshift galaxies. These data and catalog are publicly available via Internet.

  5. A survey on deep learning in medical image analysis.

    PubMed

    Litjens, Geert; Kooi, Thijs; Bejnordi, Babak Ehteshami; Setio, Arnaud Arindra Adiyoso; Ciompi, Francesco; Ghafoorian, Mohsen; van der Laak, Jeroen A W M; van Ginneken, Bram; Sánchez, Clara I

    2017-07-26

    Deep learning algorithms, in particular convolutional networks, have rapidly become a methodology of choice for analyzing medical images. This paper reviews the major deep learning concepts pertinent to medical image analysis and summarizes over 300 contributions to the field, most of which appeared in the last year. We survey the use of deep learning for image classification, object detection, segmentation, registration, and other tasks. Concise overviews are provided of studies per application area: neuro, retinal, pulmonary, digital pathology, breast, cardiac, abdominal, musculoskeletal. We end with a summary of the current state-of-the-art, a critical discussion of open challenges and directions for future research. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. The Great Observatories Origins Deep Survey: Imaging with ACS

    NASA Astrophysics Data System (ADS)

    Giavalisco, Mauro

    2002-07-01

    We propose a Treasury program of ACS imaging as part of the Great Observatories Origins Deep Survey {GOODS}, covering 320{square}', or 32* the area of the two original WFPC2 HDFs, to within 0.5-0.8 mag of their depth in four ACS bands, BViz. The two GOODS fields, the Hubble Deep Field North and Chandra Deep Field South, are the premier deep survey areas from X- ray to radio wavelengths. ACS data will provide unique angular resolution, sensitivity, and wavelength coverage to close the gap between the deepest Chandra and SIRTF observations. Supported by extensive imaging and spectroscopy from the VLT, Keck, Subaru, NOAO, Gemini, VLA, JCMT, and other facilities, the combined GOODS data set will make it possible to map the evolution of the Hubble sequence with redshift, reconstruct the history of galaxy mass assembly, star formation and nuclear activity from the epoch of reionization to the present, trace the growth of density perturbations via cosmic shear, and, with properly phased z-band observations, detect 12 Type Ia supernovae at 1.2

  7. PRIME: A Deep Near-Infrared Survey Project

    NASA Astrophysics Data System (ADS)

    Omont, A.; Prime Team; Zheng, W.; Ford, H. C.; Kruk, J. W.; Tsvetanov, Z. I.; Szalay, A. S.; Shu, P. K.; Greenhouse, M. A.; Hartig, G.; Postman, M.; Stockman, H. S.; Voit, G. M.; Lenzen, R.; Rix, H.-W.; Kent, S.; Stoughton, C.; Mellier, Y.

    PRIME is a proposed space mission for a deep survey of 25% to 100% of the sky in four near-IR bands (0.9-3.5 μm), to M AB ≈ 24 (K ≈ 22). The PRIME survey should be ~ 600 times deeper than 2MASS. Deeper surveys in selected regions are planned. Its main goal is to find the first massive objects formed: quasars up to z = 15-25 if any, galaxies up to z ~20, clusters of galaxies up to z ~ 3-5. PRIME should also be a major step in the study of brown dwarfs and nearby free floating warm planets, and serve many other goals, in particular as a pilot mission for NGST. It should be a central piece of The Virtual Observatory, complementary to other surveys.

  8. Cosmic Shear Tomography from the Deep Lens Survey

    NASA Astrophysics Data System (ADS)

    Jee, Myungkook J.; Tyson, J. Anthony; Hilbert, Stefan; Schneider, Michael; Schmidt, Samuel; Wittman, David M.

    2016-01-01

    The Deep Lens Survey (DLS) is designed as a pre-cursor Large Synoptic Survey Telescope (LSST) survey with an emphasis on depth. Using five tomographic redshift bins, we study their auto- and cross-correlations to constrain cosmological parameters. Both instrumental and astrophysical systematics are carefully addressed with the state-of-the-art techniques. We find that the cosmological leverage of the DLS is among the highest among existing >10 sq. deg cosmic shear surveys. Combining the DLS tomography with the 9-year results of the Wilkinson Microwave Anisotropy Probe (WMAP9) reduces the uncertainties of the WMAP9-only constraints by ~50%. Our constraints are fully consistent with the final Planck results and also the predictions of a LCDM universe.

  9. Two distant brown dwarfs in the UKIRT Infrared Deep Sky Survey Deep Extragalactic Survey Data Release 2

    NASA Astrophysics Data System (ADS)

    Lodieu, N.; Dobbie, P. D.; Deacon, N. R.; Venemans, B. P.; Durant, M.

    2009-05-01

    We present the discovery of two brown dwarfs in the UK infrared Telescope (UKIRT) Infrared Deep Sky Survey (UKIDSS) Deep Extragalactic Survey (DXS) Data Release 2 (DR2). Both objects were selected photometrically from 6deg2 in DXS for their blue J - K colour and the lack of optical counterparts in the Sloan Digital Sky Survey (SDSS) Stripe 82. Additional optical photometry provided by the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) corroborated the possible substellarity of these candidates. Subsequent methane imaging of UDXS J221611.51+003308.1 and UDXS J221903.10+002418.2 has confirmed them as T7 +/- 1 and T6 +/- 1 dwarfs at photometric distances of 81 (52-118 pc) and 60 (44-87 pc; 2σ confidence level). A similar search in the DR2 of the Ultra-Deep Survey over a smaller area (0.77deg2) and shallower depth did not return any late-T dwarf candidate. The numbers of late-T dwarfs in our study are broadly in line with a declining mass function when considering the current area and depth of the DXS and UDS. These brown dwarfs are the first discovered in the Visible Imaging Multi-Object Spectrograph (VIMOS) 4 field and among the few T dwarfs found in pencil-beam surveys. They are valuable to investigate the scaleheight of T dwarfs. Based on observations made with the United Kingdom Infrared Telescope, the Canada-France-Hawaii Telescope Legacy Survey and the Gemini Observatory. E-mail: nlodieu@iac.es

  10. An Introduction to the NOAO Deep Wide-Field Survey

    NASA Astrophysics Data System (ADS)

    Jannuzi, B. T.; Dey, A.; Brown, M. J. I.; Tiede, G. P.; NDWFS Team

    2004-05-01

    The NOAO Deep Wide-Field Survey (NDWFS) is a very deep optical and IR (BWRIJHK) imaging survey of 18 square degrees of the sky with the primary goal of studying the evolution of large-scale structure from redshift 1 to 4. The survey enables investigation of the formation and evolution of galaxies and the detection of luminous, very distant (z>4), star-forming galaxies and quasars. The 9.3 square degree Boötes sub-field of the survey is of particular interest because of the extensive multi-wavelength observations now available. These include Chandra (X-rays), GALEX (UV), Spitzer (near, mid, and far IR), the VLA, and Westerbork (radio). I will review the design of the survey and the processing of the optical and near-IR imaging data as a prelude to the talks following in the special session on the NDWFS Boötes field. Our research is supported by the National Optical Astronomy Observatory which is operated by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the National Science Foundation.

  11. The Texas Deep Sky Survey: Overview and First Results

    NASA Astrophysics Data System (ADS)

    vanden Berk, D. E.; Jorgensen, I.; Hill, G. J.; Claver, C. F.; Bergmann, M.; Jurcevic, J. S.; Piper, A.

    1998-12-01

    The Texas Deep Sky Survey (TDSS) is a deep, 5-color photometric and spectroscopic survey of a large area towards the North Galactic Pole, which is being carried out at McDonald Observatory. The goals of this survey are to derive the galaxy luminosity function simultaneously in 5 bands, locate galaxy clusters and map large-scale structure inside a wide contiguous volume, identify QSOs up to very high redshifts, and determine the stellar content and structure of the Galactic halo. The photometric survey currently consists of a 20 sq. deg. area which is covered in at least the B and R_C bands, and a central 2.12 x 2.12 sq. deg. area which is complete in the U, B, V, R_C, and I_C passbands, and for which about 730 spectra have so far been obtained. Approximately 50000 objects have been detected in the the central 4.5 sq. deg. imaging area, to a 5 sigma limiting magnitude of R_C=22.0. Here we describe the 5-band photometric data in the TDSS central region, and present initial object classification based upon colors and morphology.

  12. The Palomar/QUEST-DeepSky RG-610 Variability Survey

    NASA Astrophysics Data System (ADS)

    Scalzo, Richard A.; Nugent, P.; Baltay, C.; Djorgovski, S. G.; Palomar-Quest Survey Team; DeepSky Collaboration

    2009-01-01

    The QUEST-II camera, operating on the Samuel Oschin 1.3-m telescope on Mt. Palomar between July 2003 and September 2008, took data in two modes: drift scan mode in 4 filters (alternating Johnson UBRI and SDSS riz) and point-and-track mode in a red RG-610 filter. Telescope time for RG-610 imaging has been shared among several collaborations, fueling searches for near-earth asteroids by the Near Earth Asteroid Tracker (NEAT) and minor planets by the Quasar Equatorial Survey Team (QUEST), and for supernovae by the Nearby Supernova Factory (SNfactory), with over 11 million images taken in total. The DeepSky project is an initiative to reprocess the RG-610 images and to co-add them into a much deeper set of images covering 20,000 square degrees of sky to R > 23. This set of deep images will eventually serve as a reference for discovery of variable and transient phenomena through image subtraction. As another useful by-product of the necessary photometric calibration and co-addition, RG-610 light curves comprising 50+ epochs of imaging will be produced for each point source found in the DeepSky co-add, enabling detailed historical studies of the time-domain behavior of individual AGN, variable stars, supernovae and other transient phenomena discovered in a blind survey of a very large sky area. We describe the co-add and light curve data products and present first science results from the effort.

  13. Cool Dwarf Scale Heights from the Deep Lens Survey

    NASA Astrophysics Data System (ADS)

    Thorman, P.; Loomba, D.; Boeshaar, P.; Ryan, R.

    2011-12-01

    We have added 1.12 sq. deg. of survey J-band (1.2μm) deep imaging (J = 21.4, 5σ) from Palomar WIRC and 2.5 sq. deg. of targeted FLAMINGOS imaging (median depth J = 20.44, 5σ) to 4 sq. deg. of deep Rz' imaging from the Deep Lens Survey. Using color models derived from photometry and spectroscopy of known M, L, and T dwarfs, we assign a spectral type probability to each object, and calculate model likelihoods for sech2 and exponential disks of various scale heights by comparing the predicted distance distribution to the estimated object distances. The best-fit exponential scale heights for M9-L2 and L2-L5 dwarfs are ZS = 345 pc and 324 pc, respectively; however, the sech2 models show a possible decrease in the scale height from Z0 = 575 pc to 175 pc between those two groups, which may indicate a weakness in the previously used exponential models.

  14. Ultra-deep K-band Imaging of the Hubble Frontier Fields

    NASA Astrophysics Data System (ADS)

    Brammer, G. B.; Marchesini, D.; Labbé, I.; Spitler, L.; Lange-Vagle, D.; Barker, E. A.; Tanaka, M.; Fontana, A.; Galametz, A.; Ferré-Mateu, A.; Kodama, T.; Lundgren, B.; Martis, N.; Muzzin, A.; Stefanon, M.; Toft, S.; van der Wel, A.; Vulcani, B.; Whitaker, K. E.

    2016-09-01

    We have recently completed a deep near-infrared imaging survey with the High Acuity Wide Field K-band Imager (HAWK-I), nicknamed KIFF (Ks-band Imaging of the Frontier Fields). KIFF provides ultra-deep images of six fields around massive galaxy clusters that have also recently been observed with the Hubble and Spitzer Space Telescopes as part of the Frontier Fields programme. Each of the KIFF mosaics is among the deepest Ks-band images ever obtained, and, with a boost from strong gravitational lensing by the galaxy clusters, they will be used to reveal the stellar populations of galaxies seen only a few hundred million years after the Big Bang. Fully reduced images are made available to the community through the Phase 3 infrastructure of the ESO Science Archive Facility.

  15. The Great Observatories Origins Deep Survey (GOODS): Overview and Status

    NASA Astrophysics Data System (ADS)

    Hook, R. N.; GOODS Team

    2002-12-01

    GOODS is a very large project to gather deep imaging data and spectroscopic followup of two fields, the Hubble Deep Field North (HDF-N) and the Chandra Deep Field South (CDF-S), with both space and ground-based instruments to create an extensive multiwavelength public data set for community research on the distant Universe. GOODS includes a SIRTF Legacy Program (PI: Mark Dickinson) and a Hubble Treasury Program of ACS imaging (PI: Mauro Giavalisco). The ACS imaging was also optimized for the detection of high-z supernovae which are being followed up by a further target of opportunity Hubble GO Program (PI: Adam Riess). The bulk of the CDF-S ground-based data presently available comes from an ESO Large Programme (PI: Catherine Cesarsky) which includes both deep imaging and multi-object followup spectroscopy. This is currently complemented in the South by additional CTIO imaging. Currently available HDF-N ground-based data forming part of GOODS includes NOAO imaging. Although the SIRTF part of the survey will not begin until later in the year the ACS imaging is well advanced and there is also a huge body of complementary ground-based imaging and some follow-up spectroscopy which is already publicly available. We summarize the current status of GOODS and give an overview of the data products currently available and present the timescales for the future. Many early science results from the survey are presented in other GOODS papers at this meeting. Support for the HST GOODS program presented here and in companion abstracts was provided by NASA thorugh grant number GO-9425 from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555.

  16. Large Scale Structure in the Calar Alto Deep Imaging Survey

    NASA Astrophysics Data System (ADS)

    Phleps, S.; Meisenheimer, K.; Hippelein, H.

    The Calar Alto Deep Imaging Survey (CADIS) combines a deep emission line survey carried out with an imaging Fabry-Perot interferometer with a multicolor survey using three broad-band and up to 13 medium-band filters. The combination of different observing strategies facilitates not only the detection of emission line objects, but also to derive photometric spectra of all objects without time consuming single slit spectroscopy. In three fields, each measuring ≈ 1/30o, we identified a sample of 2779 field galaxies with I<23, 0.2

  17. The Canada-France Deep Fields Photometric Redshift Survey

    NASA Astrophysics Data System (ADS)

    Brodwin, M.; Lilly, S. J.; McCracken, H. J.; Foucaud, S.; Le Fèvre, O.; Crampton, D.

    2002-12-01

    The Canada-France Deep Fields is a UBVRIZ imaging survey covering 1 deg2 to I ~ 25. A template-fitting photometric redshift algorithm has been developed and rigorously tested, producing redshifts with a dispersion of Δ z/(1+z) ~ 0.08 for galaxies at 0Deep Field. Statistically motivated confidence intervals are computed taking into account the unique redshift likelihood function for each galaxy. Previous results from the CFDF include measurements of the angular correlation function of galaxies to I ~ 25 (McCracken et al. 2001, A&A, 376, 756) and of colour-selected Lyman Break Galaxies (Foucaud et al. 2002, submitted). The CFDF photometric redshift survey, calibrated with CFRS spectroscopy, was designed to study galaxy evolution since z ~ 1.3. With the full 3-D spatial information, real-space clustering and luminosity density evolution will be quantified over this redshift range. In this talk I will present the first results from the photometric redshift component of the survey.

  18. A Deep Newfirm Survey of the Orion B Cloud

    NASA Astrophysics Data System (ADS)

    Megeath, Tom; Allen, Lori; Allen, Tom; Gutermuth, Rob; Kryukova, Erin; Stutz, Amelia; Fischer, Will; Ali, Babar

    2012-08-01

    We propose deep NEWFIRM H and Ks observations of the Orion B Molecular Cloud. The Orion B cloud is the 2nd most active molecular cloud within 420 pc of the Sun, after the Orion A cloud. Spitzer identified 528 pre-main sequence stars with disks and 100 protostars in the Orion B cloud. The NEWFIRM survey will obtain deep H and Ks data with sensitivities 4-5 magnitudes deeper than the 2MASS survey. The goals are the following: Detect deeply embedded protostars: these data are a crucial input to a Herschel, Spitzer and Hubble survey of over 300 Spitzer selected protostars in the Orion A and B clouds and are needed to determine the inclination of the protostars and the geometry of their outflow cavities. Map the gas column density by extinction using the combined NEWFIRM and Spitzer 3.6 (micron) data. By correlating column density with the properties of protostars and the density of young stars, we can better understand how how the gas column density influences the rate of star formation and the properties of the nascent stars forming within the gas.

  19. A very deep IRAS survey. III - VLA observations

    NASA Astrophysics Data System (ADS)

    Hacking, Perry; Beichman, C. A.; Condon, J. J.; Houck, J. R.

    1989-04-01

    The 60-micron fluxes and positions of sources (primarily starburst galaxies) found in a deep IRAS survey by Hacking and Houck (1987) are compared with 1.49 HGz maps made by the Very Large Array. The radio results are consistent with radio measurements of brighter IRAS galaxies and provide evidence that infrared cirrus does not contaminate the 60-micron sample. The flux-independent ratio of infrared to radio flux densities implies that the 1.4 GHz luminosity function for spiral galaxies is evolving at less than (1 + z) to the power of 4 relative to the 60-micron luminosity function.

  20. Ultracool Dwarfs in the Ukirt Infrared Deep Sky Survey (UKIDSS)

    NASA Astrophysics Data System (ADS)

    Burningham, Ben; Pinfield, D.; Leggett, S. K.; Lodieu, N.; Warren, S. J.; Lucas, P. W.; Tamura, M.; Mortlock, D.; Kendall, T. R.; Jones, H. R.; Jameson, R. F.; Richard, M.; Martin, E. L.; UKIDSS Cool Dwarf Science Working Group

    2007-05-01

    The UKIRT Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS) presents an unparallelled resource for the study of field brown dwarfs. The UKIDSS Cool Dwarf Science Working Group (CDSWG) is carrying out a search for the lowest temperature brown dwarfs ever discovered, with the possibility of identifying a new spectral class of ultracool dwarf: the Y dwarf. CDSWG members identified 10 new T dwarfs in the early and first data releases of the LAS, including 2 objects with spectral types later than T7.5. One of these is thought to be the coolest T dwarf ever found with a spectral type of T8.5, and an estimated temperature of 650K. Data release 2 (DR2) took place on 1st March 2007, and already the most promising objects have been selected and followed-up photometrically and spectroscopically. In this contribution I will discuss the capabilities of UKIDSS for identifying ultracool dwarfs and summarise our latest results.

  1. Applying galactic archeology to massive galaxies using deep imaging surveys

    NASA Astrophysics Data System (ADS)

    Duc, Pierre-Alain

    2015-04-01

    Various programs aimed at exploring the still largely unknown low surface brightness Universe with deep imaging optical surveys have recently started. They open a new window for studies of galaxy evolution, pushing the technique of galactic archeology outside the Local Group (LG). The method, based on the detection and analysis of the diffuse light emitted by collisional debris or extended stellar halos (rather than on stellar counts as done for LG systems), faces however a number of technical difficulties, like the contamination of the images by reflection halos and Galactic cirrus. I review here the on-going efforts to address them and highlight the preliminary promising results obtained with a systematic survey with MegaCam on the CFHT of nearby massive early-type galaxies done as part of the ATLAS3D, NGVS and MATLAS collaborations.

  2. The Vimos VLT deep survey: compact structures in the CDFS

    NASA Astrophysics Data System (ADS)

    Adami, C.; Mazure, A.; Ilbert, O.; Cappi, A.; Bottini, D.; Garilli, B.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Picat, J. P.; Scaramella, R.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Arnaboldi, M.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Charlot, S.; Ciliegi, P.; Contini, T.; Covone, G.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Iovino, A.; Lauger, S.; McCracken, H. J.; Marano, B.; Marinoni, C.; Meneux, B.; Merighi, R.; Paltani, S.; Pellò, R.; Pollo, A.; Pozzetti, L.; Radovich, M.; Zamorani, G.; Zucca, E.; Bondi, M.; Bongiorno, A.; Busarello, G.; Gregorini, L.; Mathez, G.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2005-12-01

    We used the Vimos VLT Deep Survey in combination with other spectroscopic, photometric, and X-ray surveys from the literature to detect several galaxy structures in the Chandra Deep Field South (CDFS). Both a friend-of-friend-based algorithm applied to the spectroscopic redshift catalog and an adaptative kernel galaxy density and color maps correlated with photometric redshift estimates were used. We mainly detected a chain-like structure at z=0.66 and two massive groups at z=0.735 and 1.098 showing signs of ongoing collapse. We also detected two galaxy walls at z=0.66 and at z=0.735 (extremely compact in redshift space). The first one contains the chain-like structure and the last one contains one of the two massive groups in its center. Finally, other galaxy structures that are probably loose low mass groups were detected. We compared the group galaxy population with simulations in order to assess the richness of these structures and studied their galaxy morphological contents. The higher redshift structures appear to probably have lower velocity dispersion than the nearby ones. The number of moderately massive structures we detected is consistent with what is expected for an LCDM model, but a larger sample is required to put significant cosmological constraints.

  3. The Texas Deep Sky Survey: Spectroscopy of Cool Degenerate Stars

    NASA Astrophysics Data System (ADS)

    Claver, C. F.; Winget, D. E.; Nather, R. E.; MacQueen, P. J.

    1998-12-01

    The Texas Deep Sky Survey (TDSS) is a deep multi-color photometric survey in the direction of the North Galactic Pole. The purpose of the TDSS is to study large scale structure in the Universe and the stellar content of the Galaxy, specifically the cool end of the white dwarf luminosity function (WDLF). The TDSS will ultimately cover 100 square degrees in broadband U, B, V, R_C, and I_C plus two intermediate width filters centered on MgH and CaH to a depth of V=22. At present we have covered 100 square degrees in B and R_C and a 2.12x2.12 degree area in all seven bandpasses. Our aim of the white dwarf survey within the TDSS project is to increase, by an order of magnitude over present estimates, the number of objects used to define the WDLF below log(L/L_sun) ~ -3.0. The WDLF contains important information about the Galaxy, namely its age and star formation history, and the physics of condensed matter. However, because of their intrinsic faintness the number of cool white dwarfs presently used to define the low luminosity end of the WDLF is small, hence does not provide a meaningful constraint on theoretical models. Here we report on our initial WIYN multi-object spectroscopy of cool white dwarf candidates from a single TDSS field using a new photometric selection technique developed for finding cool degenerate stars. We describe the process of using MgH and CaH filters for selecting cool white dwarfs in the field and show its success with the discovery of 5 new spectroscopically confirmed cool white dwarfs stars.

  4. The VIRMOS deep imaging survey. IV. Near-infrared observations

    NASA Astrophysics Data System (ADS)

    Iovino, A.; McCracken, H. J.; Garilli, B.; Foucaud, S.; Le Fèvre, O.; Maccagni, D.; Saracco, P.; Bardelli, S.; Busarello, G.; Scodeggio, M.; Zanichelli, A.; Paioro, L.; Bottini, D.; Le Brun, V.; Picat, J. P.; Scaramella, R.; Tresse, L.; Vettolani, G.; Adami, C.; Arnaboldi, M.; Arnouts, S.; Bolzonella, M.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Ilbert, O.; Marano, B.; Marinoni, C.; Mazure, A.; Meneux, B.; Merighi, R.; Paltani, S.; Pellò, R.; Pollo, A.; Pozzetti, L.; Radovich, M.; Zamorani, G.; Zucca, E.; Bertin, E.; Bondi, M.; Bongiorno, A.; Cucciati, O.; Gregorini, L.; Mathez, G.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2005-11-01

    In this paper we present a new deep, wide-field near-infrared imaging survey. Our J- and K-band observations in four separate fields (0226-04, 2217+00, 1003+02, 1400+05) complement optical BVRI, ultraviolet and spectroscopic observations undertaken as part of the VIMOS-VLT deep survey (VVDS). In total, our survey spans ~400 arcmin2. Our catalogues are reliable in all fields to at least K˜20.75 and J˜21.50 (defined as the magnitude where object contamination is less than 10% and completeness greater than 90%). Taken together these four fields represents a unique combination of depth, wavelength coverage and area. Most importantly, our survey regions span a broad range of right ascension and declination which allow us to make a robust estimate of the effects of cosmic variance. We describe the complete data reduction process from raw observations to the construction of source lists and outline a comprehensive series of tests carried out to characterise the reliability of the final catalogues. From simulations we determine the completeness function of each final stacked image, and estimate the fraction of spurious sources in each magnitude bin. We compare the statistical properties of our catalogues with literature compilations. We find that our J- and K-selected galaxy counts are in good agreement with previously published works, as are our (J-K) versus K colour-magnitude diagrams. Stellar number counts extracted from our fields are consistent with a synthetic model of our galaxy. Using the location of the stellar locus in colour-magnitude space and the measured field-to-field variation in galaxy number counts we demonstrate that the absolute accuracy of our photometric calibration is at the 5% level or better. Finally, an investigation of the angular clustering of K-selected extended sources in our survey displays the expected scaling behaviour with limiting magnitude, with amplitudes in each magnitude bin in broad agreement with literature values. In summary

  5. Normal and Starburst Galaxies in Deep X-ray Surveys

    NASA Technical Reports Server (NTRS)

    Hornschemeier, Ann

    2006-01-01

    This talk will cover progress of the last several years in unraveling the nature of normal and starburst galaxies in deep X-ray surveys. This includes discussion of the normal galaxy X-ray Luminosity Function in deep field and cluster surveys and what it tells us about the binary populations in galaxies. The utility of broad band X-ray emission, especially as compared to other multiwavelength measurements of current/recent star formation, will be reviewed. These broad band X-ray measurements of star formation are based upon X-ray/Star Formation Rate correlations that span the currently available redshift range (0 < z < 1). I will also discuss new efforts underway to systematically characterize the X-ray emission from galaxies in group and cluster environments, including a new effort underway in the Coma cluster of galaxies. I will finish with discussion of the redshift frontier for studies of X-ray star formation, currently 2 approx.4, where the UV-selected Lyman Break galaxies are the best glimpse we have into X-ray emission from star formation in the early Universe. Lyman Break galaxies are of particular interest due to the overlap in basic properties with starburst galaxies in the more local Universe. Understanding the outflows in such starburst galaxies is of critical importance to constraining the "stellar" portion of cosmic feedback. The talk will close with a brief discussion of distant normal galaxy science with future X-ray observatories such as the upcoming Con-X/XEUS mission(s).

  6. Deep Infrared Survey of the Deep Chandra Field on SgrA*

    NASA Astrophysics Data System (ADS)

    Laycock, S.; Grindlay, J.; Hong, J.; Koenig, X.; Schlegel, E.; van den Berg, M.; Zhao, P.; Persson, E.

    2004-08-01

    We have observed the galactic center with the PANIC infrared imager at Magellan. In 3 nights of optimal seeing (many hours of approx. 0.3 arcsec) we obtained a 10x10 arcmin mosaic centered on SgrA*, in J,H,K and Bracket gamma. This represents the deepest IR survey surrounding SgrA* which covers the majority of the deep Chandra field obtained by Muno et al and also being studied as part of our ongoing ChaMPlane survey. The discovery of several thousand hard X-ray point sources in the GC by Muno et al a key Chandra result and this work is directed at identifying these sources, by cutting through the obscuring dust clouds and attaining the highest possible spatial resolution over the Chandra field. We will present the multicolor mosaic and preliminary analysis, concentrating on positional matches for Chandra sources. The survey is designed to find sources with colors suggestive of Be-HMXBs, CVs and other X-ray binaries. The narrow band Br-gamma data is unique in its depth and resolution and will enable discrimination of accretion sources in even the most crowded regions. This IR mosaic extends our optical work on low extinction windows in the galactic bulge (see papers by Grindlay et al and van den Berg et al), and our optical survey of the galactic bulge for ChaMPlane (see paper by Zhao et al). This work is supported by Chandra grants AR3-4002A, AR4-5003A and GO3-4033A and NSF grant AST-0098683.

  7. A Deep XMM-Newton Legacy Survey of M33

    NASA Astrophysics Data System (ADS)

    Williams, Benjamin

    We propose for financial support that will allow us to reduce and analyze all XMM- Newton data relevant to an A09 deep XMM-Newton legacy survey of M33 covering the entire optical disk with a total of 700000 seconds of exposure time. These data will allow us to determine how the temperature and energetics of the hot interstellar medium (ISM) are affected by star formation, constrain the nature and dynamical masses of new pulsating and eclipsing X-ray binaries, and perform detailed statistical and spectral studies on the largest known extragalactic population of X-ray supernova remnants (SNRs). The support proposed here is crucial for the full analysis and publication of the entire data set. Measurements and model fitting of the spectra and timing of all of the discrete sources detected in our data will constrain the nature and dynamical masses of new pulsating and eclipsing X-ray binaries, as well as provide new insight into the origins of the X-ray SNRs. Spatially-resolved, spectral studies of the diffuse emission will allow us to determine how the temperature and energetics of the hot interstellar medium (ISM) are affected by star formation. Several members of our team have already performed similar analysis to those proposed using data from the deep Chandra ACIS-I survey of M33 (ChASeM33), and we intend to hire a postdoctoral research associate who has experience working with large XMM-Newton data sets. Therefore the techniques for making the measurements are well-understood; however, the deep Chandra ACIS-I survey of M33 does not provide sufficient soft response for detailed spectral measurements of the diffuse gas emission from dozens of individual star forming regions. To reliably determine the temperature structure of the interstellar gas of these regions, our simulations show that we need to go a factor of 10 deeper in the soft X-ray band than existing X-ray data, which will be achieved with our proposed observations. Furthermore, XMM-Newton studies of X

  8. Galaxy Evolution from Deep Optical and Near-Infrared Surveys

    NASA Astrophysics Data System (ADS)

    Moustakas, Leonidas Alexander

    1998-09-01

    We use very deep optical and near-infrared imaging surveys to set constraints on galaxy evolution models, based on the numbers, colors, and morphologies of infrared-excess galaxies that are found in the field. We concentrate on a curious population of extremely faint (K > 20) infrared-excess galaxies whose blue-optical colors are not consistent with the expectations of any passive evolution models. These ``faint red-outlier galaxies'' (FROGs) are distinct from the redder and brighter ``extremely red objects'' (EROs; R-K~=6 ). In a concerted effort to identify a good sample of FROG s and to study their properties, we used Keck/NIRC to image several independent high-galactic latitude fields. Much of the analysis presented here is drawn from a very deep 3.24 arcmin2 K-band ( Klim~24 at 3σ) mosaic in the deep Westphal HST/WFPC2 pointing of the Groth Survey Strip, for which F606W and F814W data were publically available. The surface density of FROGs is found to be ~ 3.3 +/- 1 arcmin-2, more than ten times that of EROs. Whereas reliable photometric redshifts are not forthcoming without the development of more relevant models, the colors are broadly consistent with the redshift range 1.2 < z < 2.3. If placed at z ~ 1.5, FROGs occur at space densities of about 10% of the local f* space density of K-selected galaxies. To map wavelength-dependent morphologies of two FROGs, we observed a portion of our main survey field with HST/NICMOS imaging through the F160W (1.6 μm) filter. The target was resolved into two r~=0''.6 objects with similar colors, separated by ~0''.7. This is suggestive of old and dynamically-relaxed systems. The colors of FROGs are not satisfactorily fit by dust-reddened Bruzual-Charlot models at any redshift and for a broad range of assumed star formation histories. The best possible fits are consistent with very large amounts of reddening, E(B - V) ~ 1. If the infrared-excess in EROs and FROGs is taken to be entirely due to the effects of dust, then we

  9. Asteroid Size-Frequency Distribution (The ISO Deep Asteroid Survey)

    NASA Technical Reports Server (NTRS)

    Tedesco, Edward F.

    2001-01-01

    A total of six deep exposures (using AOT CAM01 with a 6" PFOV) through the ISOCAM LW10 filter (IRAS Band 1, i.e., 12 micro-m) were obtained on an approximately 15 arcminute square field centered on the ecliptic plane. Point sources were extracted using the technique described by Desert, et al. Two known asteroids appear in these frames and 20 sources moving with velocities appropriate for main belt asteroids are present. Most of the asteroids detected have flux densities less than 1 mJy, i.e., between 150 and 350 times fainter than any of the asteroids observed by Infrared Astronomy Satellite (IRAS). These data provide the first direct measurement of the 12 micro-m sky-plane density for asteroids on the ecliptic equator. The median zodiacal foreground, as measured by ISOCAM during this survey, is found to be 22.1 +/- 1.5 mJy per pixel, i.e., 26.2 +/- 1.7 MJy/sr. The results presented here imply that the actual number of kilometer-sized asteroids is significantly greater than previously believed and in reasonable agreement with the Statistical Asteroid Model.

  10. The WIRCam Deep Survey. II. Mass selected clustering

    NASA Astrophysics Data System (ADS)

    Bielby, R. M.; Gonzalez-Perez, V.; McCracken, H. J.; Ilbert, O.; Daddi, E.; Le Fèvre, O.; Hudelot, P.; Kneib, J.-P.; Mellier, Y.; Willott, C.

    2014-08-01

    We present an analysis of the clustering of galaxies from z ≈ 2 to the present day using the WIRCam Deep Survey (WIRDS). WIRDS combines deep optical data from the CFHTLS Deep fields with its own deep near-infrared data, providing a photometric data-set over an effective area of 2.4 deg2, from which accurate photometric redshifts and stellar masses can be estimated. We use the data to calculate the angular correlation function for galaxy samples split by star-formation activity, stellar mass and redshift. Using WIRDS with its large total area and multiple fields gives a low cosmic variance contribution to the error, which we estimate to be less than ~2.8%. Based on power-law fits, we estimate the real-space clustering for each sample, determining clustering lengths and power-law slopes. For galaxies selected by constant mass, we find that the clustering scale shows no evolution up to z ≈ 2. Splitting the galaxy sample by mass, we see a consistent trend for higher mass galaxies to have larger clustering scales at all redshifts considered. We use our results to test the galform semi-analytical model of galaxy formation and evolution. The observed trends are well matched by the model galaxies for both the redshift evolution and the mass dependence of the galaxy clustering. We split the galaxy population into passive and star-forming populations based on rest-frame dust-corrected NUV-r colours. We find that the passive galaxy populations show a significantly larger clustering scale at all redshifts than the star-forming population below masses of M⋆ ~ 1011 h-1 M⊙, showing that even at z ≈ 2 passive galaxies exist in denser environments than the bulk of the star-forming galaxy population. For star-forming galaxies with stellar masses of M⋆ ≳ 1011 h-1 M⊙, we find a clustering strength of ~8 h-1 Mpc across all redshifts, comparable to the measurements for the passive population. Additionally, for star-forming galaxies we see that clustering strength

  11. The Secret Lives Of Galaxies Unveiled In Deep Survey

    NASA Astrophysics Data System (ADS)

    2003-06-01

    Two of NASA's Great Observatories, bolstered by the largest ground-based telescopes around the world, are beginning to harvest new clues to the origin and evolution of galaxies. It's a bit like finding a family scrapbook containing snapshots that capture the lives of family members from infancy through adolescence to adulthood. "This is the first time the cosmic tale of how galaxies build themselves has been traced reliably to such early times in the universe's life," said Mauro Giavalisco, head of the Hubble Space Telescope (HST) portion of the survey, and research astronomer at the Space Telescope Science Institute (STScI) in Baltimore. The HST has joined forces with the Chandra X-ray Observatory to survey a relatively broad swath of sky encompassing tens of thousands of galaxies stretching far back into time. The Space Infrared Telescope Facility (SIRTF), scheduled for launch in August, will soon join this unprecedented survey. Called the Great Observatories Origins Deep Survey (GOODS), astronomers are studying galaxy formation and evolution over a wide range of distances and ages. The project is tracing the assembly history of galaxies, the evolution of their stellar populations, and the gusher of energy from star formation and active nuclei powered by immense black holes. HST astronomers report the sizes of galaxies clearly increase continuously from the time the universe was about 1 billion years old to an age of 6 billion years. This is approximately half the current age of the universe, 13.7 billion years. GOODS astronomers also find the star birth rate rose mildly, by about a factor of three, between the time the universe was about one billion years old and 1.5 billion years old, and remained high until about 7 billion years ago, when it quickly dropped to one-tenth the earlier "baby boomer" rate. This is further evidence major galaxy building trailed off when the universe was about half its current age. GOODS Chandra Deep Fields South Chandra Deep Field

  12. S-CANDELS: The Spitzer-Cosmic Assembly Near-Infrared Deep Extragalactic Survey. Survey Design, Photometry, and Deep IRAC Source Counts

    NASA Astrophysics Data System (ADS)

    Ashby, M. L. N.; Willner, S. P.; Fazio, G. G.; Dunlop, J. S.; Egami, E.; Faber, S. M.; Ferguson, H. C.; Grogin, N. A.; Hora, J. L.; Huang, J.-S.; Koekemoer, A. M.; Labbé, I.; Wang, Z.

    2015-06-01

    The Spitzer-Cosmic Assembly Deep Near-infrared Extragalactic Legacy Survey (S-CANDELS; PI G.Fazio) is a Cycle 8 Exploration Program designed to detect galaxies at very high redshifts (z\\gt 5). To mitigate the effects of cosmic variance and also to take advantage of deep coextensive coverage in multiple bands by the Hubble Space Telescope (HST) Multi-cycle Treasury Program CANDELS, S-CANDELS was carried out within five widely separated extragalactic fields: the UKIDSS Ultra-deep Survey, the Extended Chandra Deep Field South, COSMOS, the HST Deep Field North, and the Extended Groth Strip. S-CANDELS builds upon the existing coverage of these fields from the Spitzer Extended Deep Survey (SEDS), a Cycle 6 Exploration Program, by increasing the integration time from SEDS’ 12 hr to a total of 50 hr but within a smaller area, 0.16 deg2. The additional depth significantly increases the survey completeness at faint magnitudes. This paper describes the S-CANDELS survey design, processing, and publicly available data products. We present Infrared Array Camera (IRAC) dual-band 3.6+4.5 μ {{m}} catalogs reaching to a depth of 26.5 AB mag. Deep IRAC counts for the roughly 135,000 galaxies detected by S-CANDELS are consistent with models based on known galaxy populations. The increase in depth beyond earlier Spitzer/IRAC surveys does not reveal a significant additional contribution from discrete sources to the diffuse Cosmic Infrared Background (CIB). Thus it remains true that only roughly half of the estimated CIB flux from COBE/DIRBE is resolved.

  13. Accurate photometric redshifts for the CFHT legacy survey calibrated using the VIMOS VLT deep survey

    NASA Astrophysics Data System (ADS)

    Ilbert, O.; Arnouts, S.; McCracken, H. J.; Bolzonella, M.; Bertin, E.; Le Fèvre, O.; Mellier, Y.; Zamorani, G.; Pellò, R.; Iovino, A.; Tresse, L.; Le Brun, V.; Bottini, D.; Garilli, B.; Maccagni, D.; Picat, J. P.; Scaramella, R.; Scodeggio, M.; Vettolani, G.; Zanichelli, A.; Adami, C.; Bardelli, S.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Cucciati, O.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Marano, B.; Marinoni, C.; Mazure, A.; Meneux, B.; Merighi, R.; Paltani, S.; Pollo, A.; Pozzetti, L.; Radovich, M.; Zucca, E.; Bondi, M.; Bongiorno, A.; Busarello, G.; de La Torre, S.; Gregorini, L.; Lamareille, F.; Mathez, G.; Merluzzi, P.; Ripepi, V.; Rizzo, D.; Vergani, D.

    2006-10-01

    Aims. We present and release photometric redshifts for a uniquely large and deep sample of 522286 objects with i'_AB≤ 25 in the Canada-France Hawaii Telescope Legacy Survey (CFHTLS) "Deep Survey" fields D1, D2, D3, and D4, which cover a total effective area of 3.2 °^2. Methods: . We use 3241 spectroscopic redshifts with 0 ≤ z ≤ 5 from the VIMOS VLT Deep Survey (VVDS) as a calibration and training set to derive these photometric redshifts. Using the "Le Phare" photometric redshift code, we developed a robust calibration method based on an iterative zero-point refinement combined with a template optimisation procedure and the application of a Bayesian approach. This method removes systematic trends in the photometric redshifts and significantly reduces the fraction of catastrophic errors (by a factor of 2), a significant improvement over traditional methods. We use our unique spectroscopic sample to present a detailed assessment of the robustness of the photometric redshift sample. Results: . For a sample selected at i'_AB≤ 24, we reach a redshift accuracy of σΔ z/(1+z)=0.029 with η=3.8% of catastrophic errors (η is defined strictly as those objects with |Δ z|/(1+z) > 0.15). The reliability of our photometric redshifts decreases for faint objects: we find σΔ z/(1+z)=0.025, 0.034 and η=1.9%, 5.5% for samples selected at i'_AB=17.5-22.5 and 22.5-24 respectively. We find that the photometric redshifts of starburst galaxies are less reliable: although these galaxies represent only 22% of the spectroscopic sample, they are responsible for 50% of the catastrophic errors. An analysis as a function of redshift demonstrates that our photometric redshifts work best in the redshift range 0.2≤ z ≤ 1.5. We find an excellent agreement between the photometric and the VVDS spectroscopic redshift distributions at i'_AB≤ 24. Finally, we compare the redshift distributions of i' selected galaxies on the four CFHTLS deep fields, showing that cosmic variance is

  14. Deep near-infrared survey of the Southern Sky (DENIS)

    NASA Technical Reports Server (NTRS)

    Deul, E.

    1992-01-01

    DENIS (Deep Near-Infrared Survey of the Southern Sky) will be the first complete census of astronomical sources in the near-infrared spectral range. The challenges of this novel survey are both scientific and technical. Phenomena radiating in the near-infrared range from brown dwarfs to galaxies in the early stages of cosmological evolution, the scientific exploitation of data relevant over such a wide range requires pooling expertise from several of the leading European astronomical centers. The technical challenges of a project which will provide an order of magnitude more sources than given by the IRAS space mission, and which will involve advanced data-handling and image-processing techniques, likewise require pooling of hardware and software resources, as well as of human expertise. The DENIS project team is composed of some 40 scientists, computer specialists, and engineers located in 5 European Community countries (France, Germany, Italy, The Netherlands, and Spain), with important contributions from specialists in Australia, Brazil, Chile, and Hungary. DENIS will survey the entire southern sky in 3 colors, namely in the I band at a wavelength of 0.8 micron, in the 1.25 micron J band, and in the 2.15 micron K' band. The sensitivity limits will be 18th magnitude in the I band, 16th in the J band, and 14.5th in the K' band. The angular resolution achieved will be 1 arcsecond in the I band, and 3.0 arcseconds in the J and K' bands. The European Southern Observatory 1 m telescope on La Silla will be dedicated to survey use during operations expected to last four years, commencing in late 1993. DENIS aims to provide the astronomical community with complete digitized infrared images of the full southern sky and a catalogue of extracted objects, both of the best quality and in readily accessible form. This will be achieved through dedicated software packages and specialized catalogues, and with assistance from the Leiden and Paris Data Analysis Centers. The data

  15. The VIMOS-VLT deep survey: the group catalogue

    NASA Astrophysics Data System (ADS)

    Cucciati, O.; Marinoni, C.; Iovino, A.; Bardelli, S.; Adami, C.; Mazure, A.; Scodeggio, M.; Maccagni, D.; Temporin, S.; Zucca, E.; De Lucia, G.; Blaizot, J.; Garilli, B.; Meneux, B.; Zamorani, G.; Le Fèvre, O.; Cappi, A.; Guzzo, L.; Bottini, D.; Le Brun, V.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Arnouts, S.; Bolzonella, M.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Ilbert, O.; Lamareille, F.; McCracken, H. J.; Marano, B.; Merighi, R.; Paltani, S.; Pellò, R.; Pollo, A.; Pozzetti, L.; Vergani, D.; Pérez-Montero, E.

    2010-09-01

    Aims: We present a homogeneous and complete catalogue of optical galaxy groups identified in the purely flux-limited (17.5 ≤ IAB ≤ 24.0) VIMOS-VLT deep redshift Survey (VVDS). Methods: We use mock catalogues extracted from the Millennium Simulation, to correct for potential systematics that might affect the overall distribution as well as the individual properties of the identified systems. Simulated samples allow us to forecast the number and properties of groups that can be potentially found in a survey with VVDS-like selection functions. We use them to correct for the expected incompleteness and, to asses in addition, how well galaxy redshifts trace the line-of-sight velocity dispersion of the underlying mass overdensity. In particular, on these mock catalogues we train the adopted group-finding technique i.e., the Voronoi-Delaunay Method (VDM). The goal is to fine-tune its free parameters, recover in a robust and unbiased way the redshift and velocity dispersion distributions of groups (n(z) and n(σ), respectively), and maximize, at the same time, the level of completeness and purity of the group catalogue. Results: We identify 318 VVDS groups with at least 2 members in the range 0.2 ≤ z ≤ 1.0, among which 144 (/30) with at least 3 (/5) members. The sample has an overall completeness of ~60% and a purity of ~50%. Nearly 45% of the groups with at least 3 members are still recovered if we run the algorithm with a particular parameter set that maximizes the purity (~75%) of the resulting catalogue. We use the group sample to explore the redshift evolution of the fraction fb of blue galaxies (U-B ≤ 1) in the redshift range 0.2 ≤ z ≤ 1. We find that the fraction of blue galaxies is significantly lower in groups than in the global population (i.e. in the whole ensemble of galaxies irrespective of their environment). Both of these quantities increase with redshift, the fraction of blue galaxies in groups exhibiting a marginally significant steeper

  16. ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: Survey Description

    NASA Astrophysics Data System (ADS)

    Walter, Fabian; Decarli, Roberto; Aravena, Manuel; Carilli, Chris; Bouwens, Rychard; da Cunha, Elisabete; Daddi, Emanuele; Ivison, R. J.; Riechers, Dominik; Smail, Ian; Swinbank, Mark; Weiss, Axel; Anguita, Timo; Assef, Roberto; Bacon, Roland; Bauer, Franz; Bell, Eric F.; Bertoldi, Frank; Chapman, Scott; Colina, Luis; Cortes, Paulo C.; Cox, Pierre; Dickinson, Mark; Elbaz, David; Gónzalez-López, Jorge; Ibar, Edo; Inami, Hanae; Infante, Leopoldo; Hodge, Jacqueline; Karim, Alex; Le Fevre, Olivier; Magnelli, Benjamin; Neri, Roberto; Oesch, Pascal; Ota, Kazuaki; Popping, Gergö; Rix, Hans-Walter; Sargent, Mark; Sheth, Kartik; van der Wel, Arjen; van der Werf, Paul; Wagg, Jeff

    2016-12-01

    We present the rationale for and the observational description of ASPECS: the ALMA SPECtroscopic Survey in the Hubble Ultra-Deep Field (UDF), the cosmological deep field that has the deepest multi-wavelength data available. Our overarching goal is to obtain an unbiased census of molecular gas and dust continuum emission in high-redshift (z > 0.5) galaxies. The ˜1‧ region covered within the UDF was chosen to overlap with the deepest available imaging from the Hubble Space Telescope. Our ALMA observations consist of full frequency scans in band 3 (84-115 GHz) and band 6 (212-272 GHz) at approximately uniform line sensitivity ({L}{CO}\\prime ˜ 2 × 109 K km s-1 pc2), and continuum noise levels of 3.8 μJy beam-1 and 12.7 μJy beam-1, respectively. The molecular surveys cover the different rotational transitions of the CO molecule, leading to essentially full redshift coverage. The [C ii] emission line is also covered at redshifts 6.0\\lt z\\lt 8.0. We present a customized algorithm to identify line candidates in the molecular line scans and quantify our ability to recover artificial sources from our data. Based on whether multiple CO lines are detected, and whether optical spectroscopic redshifts as well as optical counterparts exist, we constrain the most likely line identification. We report 10 (11) CO line candidates in the 3 mm (1 mm) band, and our statistical analysis shows that <4 of these (in each band) are likely spurious. Less than one-third of the total CO flux in the low-J CO line candidates are from sources that are not associated with an optical/NIR counterpart. We also present continuum maps of both the band 3 and band 6 observations. The data presented here form the basis of a number of dedicated studies that are presented in subsequent papers.

  17. EXTENDED PHOTOMETRY FOR THE DEEP2 GALAXY REDSHIFT SURVEY: A TESTBED FOR PHOTOMETRIC REDSHIFT EXPERIMENTS

    SciTech Connect

    Matthews, Daniel J.; Newman, Jeffrey A.; Coil, Alison L.; Cooper, Michael C.; Gwyn, Stephen D. J. E-mail: janewman@pitt.edu E-mail: m.cooper@uci.edu

    2013-02-15

    This paper describes a new catalog that supplements the existing DEEP2 Galaxy Redshift Survey photometric and spectroscopic catalogs with ugriz photometry from two other surveys: the Canada-France-Hawaii Legacy Survey (CFHTLS) and the Sloan Digital Sky Survey (SDSS). Each catalog is cross-matched by position on the sky in order to assign ugriz photometry to objects in the DEEP2 catalogs. We have recalibrated the CFHTLS photometry where it overlaps DEEP2 in order to provide a more uniform data set. We have also used this improved photometry to predict DEEP2 BRI photometry in regions where only poorer measurements were available previously. In addition, we have included improved astrometry tied to SDSS rather than USNO-A2.0 for all DEEP2 objects. In total this catalog contains {approx}27, 000 objects with full ugriz photometry as well as robust spectroscopic redshift measurements, 64% of which have r > 23. By combining the secure and accurate redshifts of the DEEP2 Galaxy Redshift Survey with ugriz photometry, we have created a catalog that can be used as an excellent testbed for future photo-z studies, including tests of algorithms for surveys such as LSST and DES.

  18. DeepLensing: The Use of Deep Machine Learning to Find Strong Gravitational Lenses in Astronomical Surveys

    NASA Astrophysics Data System (ADS)

    Nord, Brian

    2017-01-01

    Strong gravitational lenses have potential as very powerful probes of dark energy and cosmic structure. However, efficiently finding lenses poses a significant challenge—especially in the era of large-scale cosmological surveys. I will present a new application of deep machine learning algorithms to find strong lenses, as well as the strong lens discovery program of the Dark Energy Survey (DES).Strong lenses provide unique information about the evolution of distant galaxies, the nature of dark energy, and the shapes of dark matter haloes. Current and future surveys, like DES and the Large Synoptic Survey Telescope, present an opportunity to find many thousands of strong lenses, far more than have ever been discovered. By and large, searches have heretofore relied on the time-consuming effort of human scanners. Deep machine learning frameworks, like convolutional neural nets, have revolutionized the task of image recognition, and have a natural place in the processing of astronomical images, including the search for strong lenses.Over five observing seasons, which started in August 2013, DES will carry out a wide-field survey of 5000 square degrees of the Southern Galactic Cap. DES has identified nearly 200 strong lensing candidates in the first two seasons of data. We have performed spectroscopic follow-up on a subsample of these candidates at Gemini South, confirming over a dozen new strong lenses. I will present this DES discovery program, including searches and spectroscopic follow-up of galaxy-scale, cluster-scale and time-delay lensing systems.I will focus, however, on a discussion of the successful search for strong lenses using deep learning methods. In particular, we show that convolutional neural nets present a new set of tools for efficiently finding lenses, and accelerating advancements in strong lensing science.

  19. DEEP 21 cm H I OBSERVATIONS AT z {approx} 0.1: THE PRECURSOR TO THE ARECIBO ULTRA DEEP SURVEY

    SciTech Connect

    Freudling, Wolfram; Zwaan, Martin; Staveley-Smith, Lister; Meyer, Martin; Catinella, Barbara; Minchin, Robert; Calabretta, Mark; Momjian, Emmanuel; O'Neil, Karen

    2011-01-20

    The 'ALFA Ultra Deep Survey' (AUDS) is an ongoing 21 cm spectral survey with the Arecibo 305 m telescope. AUDS will be the most sensitive blind survey undertaken with Arecibo's 300 MHz Mock spectrometer. The survey searches for 21 cm H I line emission at redshifts between 0 and 0.16. The main goals of the survey are to investigate the H I content and probe the evolution of H I gas within that redshift region. In this paper, we report on a set of precursor observations with a total integration time of 53 hr. The survey detected a total of eighteen 21 cm emission lines at redshifts between 0.07 and 0.15 in a region centered around {alpha}{sub 2000} {approx} 0{sup h}, {delta} {approx} 15{sup 0}42'. The rate of detection is consistent with the one expected from the local H I mass function. The derived relative H I density at the median redshift of the survey is {rho}{sub H{sub I}}[z = 0.125] = (1.0 {+-} 0.3){rho}{sub 0}, where {rho}{sub 0} is the H I density at zero redshift.

  20. Deep X-ray spectroscopy of obscured AGN in the ultra-deep XMM surveys of the Chandra Deep Field South (CDFS)

    NASA Astrophysics Data System (ADS)

    Comastri, Andrea; Ranalli, P.; Vignali, C.; Cappelluti, N.; Gilli, R.; Iwasawa, K.; Carrera, F. J.; Brusa, M.; Vito, F.; Georgantopoulos, I.; Rovilos, E.; Fiore, F.; Civano, F.; Brandt, W. N.; Tozzi, P.; Barcons, X.; Puccetti, S.; Falocco, S.; Paolillo, M.

    2012-09-01

    According to the recent models for the joint evolution of Super Massive Black Holes and their Host Galaxies, heavy obscuration represents a crucial phase and is expected to play a key role in the feedback mechanisms self regulating the SMBH growth. The smoking gun signature of heavy absorption is the presence of a low energy cut-off and/or reflection signatures (i.e. iron lines and edges) in the X-ray spectrum. Deep X-ray spectroscopy represents the most efficient method to uncover the most obscured sources at cosmological distances. After a brief description of the XMM ultra-deep (3 Ms) survey in the CDFS, I will present the results of a systematic search for heavily obscured and Compton thick AGN and discuss the results in the light of recent phenomenological (i.e. XRB synthesis) and theoretical models. I will also highlight the power of deep spectral spectroscopy to obtain redshift estimates, via the iron line, more accurate and reliable than available photo-z. Synergies between ultra-deep Chandra (4 Ms) and XMM observations and perspectives for future surveys will be also reported.

  1. CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey

    NASA Astrophysics Data System (ADS)

    Grogin, Norman A.; Kocevski, Dale D.; Faber, S. M.; Ferguson, Henry C.; Koekemoer, Anton M.; Riess, Adam G.; Acquaviva, Viviana; Alexander, David M.; Almaini, Omar; Ashby, Matthew L. N.; Barden, Marco; Bell, Eric F.; Bournaud, Frédéric; Brown, Thomas M.; Caputi, Karina I.; Casertano, Stefano; Cassata, Paolo; Castellano, Marco; Challis, Peter; Chary, Ranga-Ram; Cheung, Edmond; Cirasuolo, Michele; Conselice, Christopher J.; Roshan Cooray, Asantha; Croton, Darren J.; Daddi, Emanuele; Dahlen, Tomas; Davé, Romeel; de Mello, Duília F.; Dekel, Avishai; Dickinson, Mark; Dolch, Timothy; Donley, Jennifer L.; Dunlop, James S.; Dutton, Aaron A.; Elbaz, David; Fazio, Giovanni G.; Filippenko, Alexei V.; Finkelstein, Steven L.; Fontana, Adriano; Gardner, Jonathan P.; Garnavich, Peter M.; Gawiser, Eric; Giavalisco, Mauro; Grazian, Andrea; Guo, Yicheng; Hathi, Nimish P.; Häussler, Boris; Hopkins, Philip F.; Huang, Jia-Sheng; Huang, Kuang-Han; Jha, Saurabh W.; Kartaltepe, Jeyhan S.; Kirshner, Robert P.; Koo, David C.; Lai, Kamson; Lee, Kyoung-Soo; Li, Weidong; Lotz, Jennifer M.; Lucas, Ray A.; Madau, Piero; McCarthy, Patrick J.; McGrath, Elizabeth J.; McIntosh, Daniel H.; McLure, Ross J.; Mobasher, Bahram; Moustakas, Leonidas A.; Mozena, Mark; Nandra, Kirpal; Newman, Jeffrey A.; Niemi, Sami-Matias; Noeske, Kai G.; Papovich, Casey J.; Pentericci, Laura; Pope, Alexandra; Primack, Joel R.; Rajan, Abhijith; Ravindranath, Swara; Reddy, Naveen A.; Renzini, Alvio; Rix, Hans-Walter; Robaina, Aday R.; Rodney, Steven A.; Rosario, David J.; Rosati, Piero; Salimbeni, Sara; Scarlata, Claudia; Siana, Brian; Simard, Luc; Smidt, Joseph; Somerville, Rachel S.; Spinrad, Hyron; Straughn, Amber N.; Strolger, Louis-Gregory; Telford, Olivia; Teplitz, Harry I.; Trump, Jonathan R.; van der Wel, Arjen; Villforth, Carolin; Wechsler, Risa H.; Weiner, Benjamin J.; Wiklind, Tommy; Wild, Vivienne; Wilson, Grant; Wuyts, Stijn; Yan, Hao-Jing; Yun, Min S.

    2011-12-01

    The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) is designed to document the first third of galactic evolution, over the approximate redshift (z) range 8-1.5. It will image >250,000 distant galaxies using three separate cameras on the Hubble Space Telescope, from the mid-ultraviolet to the near-infrared, and will find and measure Type Ia supernovae at z > 1.5 to test their accuracy as standardizable candles for cosmology. Five premier multi-wavelength sky regions are selected, each with extensive ancillary data. The use of five widely separated fields mitigates cosmic variance and yields statistically robust and complete samples of galaxies down to a stellar mass of 109 M ⊙ to z ≈ 2, reaching the knee of the ultraviolet luminosity function of galaxies to z ≈ 8. The survey covers approximately 800 arcmin2 and is divided into two parts. The CANDELS/Deep survey (5σ point-source limit H = 27.7 mag) covers ~125 arcmin2 within Great Observatories Origins Deep Survey (GOODS)-N and GOODS-S. The CANDELS/Wide survey includes GOODS and three additional fields (Extended Groth Strip, COSMOS, and Ultra-deep Survey) and covers the full area to a 5σ point-source limit of H >~ 27.0 mag. Together with the Hubble Ultra Deep Fields, the strategy creates a three-tiered "wedding-cake" approach that has proven efficient for extragalactic surveys. Data from the survey are nonproprietary and are useful for a wide variety of science investigations. In this paper, we describe the basic motivations for the survey, the CANDELS team science goals and the resulting observational requirements, the field selection and geometry, and the observing design. The Hubble data processing and products are described in a companion paper.

  2. CANDELS: THE COSMIC ASSEMBLY NEAR-INFRARED DEEP EXTRAGALACTIC LEGACY SURVEY

    SciTech Connect

    Grogin, Norman A.; Ferguson, Henry C.; Koekemoer, Anton M.; Brown, Thomas M.; Casertano, Stefano; Kocevski, Dale D.; Faber, S. M.; Acquaviva, Viviana; Alexander, David M.; Almaini, Omar; Ashby, Matthew L. N.; Barden, Marco; Bell, Eric F.; Bournaud, Frederic; Cassata, Paolo; Castellano, Marco; Challis, Peter; Chary, Ranga-Ram; and others

    2011-12-01

    The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) is designed to document the first third of galactic evolution, over the approximate redshift (z) range 8-1.5. It will image >250,000 distant galaxies using three separate cameras on the Hubble Space Telescope, from the mid-ultraviolet to the near-infrared, and will find and measure Type Ia supernovae at z > 1.5 to test their accuracy as standardizable candles for cosmology. Five premier multi-wavelength sky regions are selected, each with extensive ancillary data. The use of five widely separated fields mitigates cosmic variance and yields statistically robust and complete samples of galaxies down to a stellar mass of 10{sup 9} M{sub Sun} to z Almost-Equal-To 2, reaching the knee of the ultraviolet luminosity function of galaxies to z Almost-Equal-To 8. The survey covers approximately 800 arcmin{sup 2} and is divided into two parts. The CANDELS/Deep survey (5{sigma} point-source limit H = 27.7 mag) covers {approx}125 arcmin{sup 2} within Great Observatories Origins Deep Survey (GOODS)-N and GOODS-S. The CANDELS/Wide survey includes GOODS and three additional fields (Extended Groth Strip, COSMOS, and Ultra-deep Survey) and covers the full area to a 5{sigma} point-source limit of H {approx}> 27.0 mag. Together with the Hubble Ultra Deep Fields, the strategy creates a three-tiered 'wedding-cake' approach that has proven efficient for extragalactic surveys. Data from the survey are nonproprietary and are useful for a wide variety of science investigations. In this paper, we describe the basic motivations for the survey, the CANDELS team science goals and the resulting observational requirements, the field selection and geometry, and the observing design. The Hubble data processing and products are described in a companion paper.

  3. Deep seismic reflection survey of Queen Charlotte basin

    SciTech Connect

    Rohr, K.; Dietrich, J. )

    1990-05-01

    One thousand kilometers of 14 sec marine seismic reflection data collected in the Queen Charlotte basin region in 1988 provide excellent images of Tertiary sedimentary basin fill as well as deep crustal structure. The Tertiary section is highly variable in thickness, with up to 6,500 m of strata occurring in the deepest depocenters in a complex array of subbasins and half-grabens. Widespread extensional deformation including normal faulting during basin development was followed later by compressional deformation in the northern half of the basin. Sediments have been compressed into open folds and flower structures; some normal faults have been reactivated as reverse faults. Seismic interpretations of structural features suggest that Tertiary extension and compression have developed in response to strike-slip tectonics. Crust under Hecate Strait is more reflective than under Queen Charlotte Sound; geological interpretation of these discontinuous and structurally variable crustal reflections requires further analysis. In some areas of the basin (e.g., near the Sockeye wells, Hecate Strait) coherent reflections occur directly beneath the Tertiary section and may be images of Mesozoic strata. Deep reflections damaged at times of 7.0 to 10.0 sec on many profiles, provide for the seismic differentiation between reflective lower crust and nonreflective upper mantle. Estimated crustal thicknesses of 18-21 km beneath Hecate Strait and Queen Charlotte Sound indicate significant coastal thinning beneath the Queen Charlotte basin.

  4. The VIMOS VLT Deep Survey: A new window on the distant universe

    NASA Astrophysics Data System (ADS)

    Le Fèvre, O.; Vettolani, G.; Garilli, B.; Tresse, L.; Bottini, D.; Le Brun, V.; Maccagni, D.; Picat, J.-P.; Scaramella, R.; Scodeggio, M.; Zanichelli, A.; Adami, C.; Arnaboldi, M.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Ilbert, O.; Iovino, A.; McCracken, H. J.; Marano, B.; Marinoni, C.; Mathez, G.; Mazure, A.; Meneux, B.; Merighi, R.; Paltani, S.; Pelló, R.; Pollo, A.; Pozzetti, L.; Radovich, M.; Zamorani, G.; Zucca, E.; Bondi, M.; Bongiorno, A.; Busarello, G.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2005-12-01

    The First Epoch VIMOS VLT Deep Survey is now completed. More than 11000 redshifts of galaxies with 17.5 ≤ IAB ≤ 24 have been measured with the VIMOS spectrograph build for ESO by our consortium of French and Italian Institutes. The magnitude selection of this survey is unique and allows an unprecedented census of the high redshift universe to trace the evolution of galaxies and AGNs from 12 billion years ago to the present. We present here the main results from this first epoch survey. A first public data release offers access to the deep imaging and to 1599 galaxies with redshifts in the Chandra Deep Field South. The VVDS continues beyond the first epoch, a total of more than 45000 spectra have been obtained and processing is on-going.

  5. The VIMOS VLT Deep Survey. Public release of 1599 redshifts to IAB≤24 across the Chandra Deep Field South

    NASA Astrophysics Data System (ADS)

    Le Fèvre, O.; Vettolani, G.; Paltani, S.; Tresse, L.; Zamorani, G.; Le Brun, V.; Moreau, C.; Bottini, D.; Maccagni, D.; Picat, J. P.; Scaramella, R.; Scodeggio, M.; Zanichelli, A.; Adami, C.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Cappi, A.; Charlot, S.; Contini, T.; Foucaud, S.; Franzetti, P.; Garilli, B.; Gavignaud, I.; Guzzo, L.; Ilbert, O.; Iovino, A.; McCracken, H. J.; Mancini, D.; Marano, B.; Marinoni, C.; Mathez, G.; Mazure, A.; Meneux, B.; Merighi, R.; Pellò, R.; Pollo, A.; Pozzetti, L.; Radovich, M.; Zucca, E.; Arnaboldi, M.; Bondi, M.; Bongiorno, A.; Busarello, G.; Ciliegi, P.; Gregorini, L.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2004-12-01

    This paper presents the VIMOS VLT Deep Survey around the Chandra Deep Field South (CDFS). We have measured 1599 new redshifts with VIMOS on the European Observatory Very Large Telescope - UT3, in an area 21 × 21.6 arcmin2, including 784 redshifts in the Hubble Space Telescope - Advanced Camera for Surveys GOODS area. 30% of all objects with IAB=24 have been observed independently of magnitude, indicating that the sample is purely magnitude limited. We have reached an unprecedented completeness level of 84% in terms of the ratio of secure measurements vs. observed objects, while 95% of all objects have a redshift measurement. A total of 1452 galaxies, 139 stars, 8 QSOs have a redshift identification, 141 of these being unsecure measurements. The redshift distribution down to IAB=24 is peaked at a median redshift z=0.73, with a significant high redshift tail extending up to ˜4. Several high density peaks in the distribution of galaxies are identified. In particular, the strong peak at z=0.735 contains more than 130 galaxies in a velocity range ±2000 km s-1 distributed all across the transverse ˜20 h-1 Mpc of the survey. We are releasing all redshifts to the community, along with the cross identification with HST-ACS GOODS sources on the CENCOS database environment http://cencosw.oamp.fr. The data presented in this paper has been obtained with the European Southern Observatory Very Large Telescope, Paranal, Chile.

  6. Deep Near-Infrared Surveys and Young Brown Dwarf Populations in Star-Forming Regions

    NASA Astrophysics Data System (ADS)

    Tamura, M.; Naoi, T.; Oasa, Y.; Nakajima, Y.; Nagashima, C.; Nagayama, T.; Baba, D.; Nagata, T.; Sato, S.; Kato, D.; Kurita, M.; Sugitani, K.; Itoh, Y.; Nakaya, H.; Pickles, A.

    2003-06-01

    We are currently conducting three kinds of IR surveys of star forming regions (SFRs) in order to seek for very low-mass young stellar populations. First is a deep JHKs-bands (simultaneous) survey with the SIRIUS camera on the IRSF 1.4m or the UH 2.2m telescopes. Second is a very deep JHKs survey with the CISCO IR camera on the Subaru 8.2m telescope. Third is a high resolution companion search around nearby YSOs with the CIAO adaptive optics coronagraph IR camera on the Subaru. In this contribution, we describe our SIRIUS camera and present preliminary results of the ongoing surveys with this new instrument.

  7. A Deep Chandra ACIS Survey of M51

    NASA Astrophysics Data System (ADS)

    Kuntz, K. D.; Long, Knox S.; Kilgard, Roy E.

    2016-08-01

    We have obtained a deep X-ray image of the nearby galaxy M51 using Chandra. Here we present the catalog of X-ray sources detected in these observations and provide an overview of the properties of the point-source population. We find 298 sources within the D 25 radii of NGC 5194/5, of which 20% are variable, a dozen are classical transients, and another half dozen are transient-like sources. The typical number of active ultraluminous X-ray sources in any given observation is ˜5, and only two of those sources persist in an ultraluminous state over the 12 yr of observations. Given reasonable assumptions about the supernova remnant population, the luminosity function is well described by a power law with an index between 1.55 and 1.7, only slightly shallower than that found for populations dominated by high-mass X-ray binaries (HMXBs), which suggests that the binary population in NGC 5194 is also dominated by HMXBs. The luminosity function of NGC 5195 is more consistent with a low-mass X-ray binary dominated population. Based on observations made with NASA's Chandra X-ray Observatory, which is operated by the Smithsonian Astrophysical Observatory under contract #NAS83060, and the data were obtained through program GO1-12115.

  8. DEEP, AEGIS, & CATS - Pathfinding Surveys to the Next Generation of Distant Galaxy Stellar Population Research

    NASA Astrophysics Data System (ADS)

    Koo, David C.

    2010-04-01

    DEEP, AEGIS, and CATS are examples of spectroscopic, multiwavelength, and adaptive optics surveys, respectively, that are pushing the frontiers of stellar population studies of distant galaxies. Together, these surveys affirm the unprecedented richness of high quality information that can already be gathered using today's generation of ground and space telescopes. We highlight several results in extracting the stellar and dynamical masses, chemical abundances, ages, and frequency of galactic winds for galaxies at redshifts up to z ~ 1.4.

  9. Radio variability in the Phoenix Deep Survey at 1.4 GHz

    NASA Astrophysics Data System (ADS)

    Hancock, P. J.; Drury, J. A.; Bell, M. E.; Murphy, T.; Gaensler, B. M.

    2016-09-01

    We use archival data from the Phoenix Deep Survey to investigate the variable radio source population above 1 mJy beam-1 at 1.4 GHz. Given the similarity of this survey to other such surveys we take the opportunity to investigate the conflicting results which have appeared in the literature. Two previous surveys for variability conducted with the Very Large Array (VLA) achieved a sensitivity of 1 mJy beam-1. However, one survey found an areal density of radio variables on time-scales of decades that is a factor of ˜4 times greater than a second survey which was conducted on time-scales of less than a few years. In the Phoenix deep field we measure the density of variable radio sources to be ρ = 0.98 deg-2 on time-scales of 6 months to 8 yr. We make use of Wide-field Infrared Survey Explorer infrared cross-ids, and identify all variable sources as an active galactic nucleus of some description. We suggest that the discrepancy between previous VLA results is due to the different time-scales probed by each of the surveys, and that radio variability at 1.4 GHz is greatest on time-scales of 2-5 yr.

  10. The Subaru/XMM-Newton Deep Survey (SXDS). V. Optically Faint Variable Object Survey

    NASA Astrophysics Data System (ADS)

    Morokuma, Tomoki; Doi, Mamoru; Yasuda, Naoki; Akiyama, Masayuki; Sekiguchi, Kazuhiro; Furusawa, Hisanori; Ueda, Yoshihiro; Totani, Tomonori; Oda, Takeshi; Nagao, Tohru; Kashikawa, Nobunari; Murayama, Takashi; Ouchi, Masami; Watson, Mike G.; Richmond, Michael W.; Lidman, Christopher; Perlmutter, Saul; Spadafora, Anthony L.; Aldering, Greg; Wang, Lifan; Hook, Isobel M.; Knop, Rob A.

    2008-03-01

    We present our survey for optically faint variable objects using multiepoch (8-10 epochs over 2-4 years) i'-band imaging data obtained with Subaru Suprime-Cam over 0.918 deg2 in the Subaru/XMM-Newton Deep Field (SXDF). We found 1040 optically variable objects by image subtraction for all the combinations of images at different epochs. This is the first statistical sample of variable objects at depths achieved with 8-10 m class telescopes or the Hubble Space Telescope. The detection limit for variable components is i'vari ~ 25.5 mag. These variable objects were classified into variable stars, supernovae (SNe), and active galactic nuclei (AGNs), based on the optical morphologies, magnitudes, colors, and optical-mid-infrared colors of the host objects, spatial offsets of variable components from the host objects, and light curves. Detection completeness was examined by simulating light curves for periodic and irregular variability. We detected optical variability for 36% +/- 2% (51% +/- 3% for a bright sample with i' < 24.4 mag) of X-ray sources in the field. Number densities of variable objects as functions of time intervals Δ t and variable component magnitudes i'vari are obtained. Number densities of variable stars, SNe, and AGNs are 120, 489, and 579 objects deg-2, respectively. Bimodal distributions of variable stars in the color-magnitude diagrams indicate that the variable star sample consists of bright (V ~ 22 mag) blue variable stars of the halo population and faint (V ~ 23.5 mag) red variable stars of the disk population. There are a few candidates of RR Lyrae providing a possible number density of ~10-2 kpc-3 at a distance of >150 kpc from the Galactic center. Based in part on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan. Based on observations (program GN-2002B-Q-30) obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a

  11. Obscured quasars at high redshift in the UKIDSS Ultra Deep Survey

    NASA Astrophysics Data System (ADS)

    Botti, Ismael; Almaini, Omar; Hartley, Will; Mortlock, Alice; Lira, Paulina

    2014-07-01

    Obscured quasars hidden in deep X-ray surveys can be recovered by looking at mid-infrared wavelengths, where dust re-radiates the absorbed radiation. Here we present a sample of obscured quasars in the redshift range 1 < z < 4 based on data from the UKIDSS Ultra-Deep Survey (UDS), the deepest near-IR survey over ~ 1 sq. deg. to date. Candidates that are primarily selected by their 24 μm emission are probed by decomposing their spectral energy distribution (SED) to disentangle the emission from the AGN and its host galaxy. We show preliminary results on their host galaxy properties as well as their clustering, showing that obscured quasars are found in galaxies located in the green valley, residing in dark matter haloes not different from normal galaxies at those redshifts.

  12. Contamination by field late-M, L, and T dwarfs in deep surveys

    NASA Astrophysics Data System (ADS)

    Caballero, J. A.; Burgasser, A. J.; Klement, R.

    2008-09-01

    Context: Deep photometric surveys of substellar objects in young clusters and high-redshift quasars are affected by contaminant sources at different heliocentric distances. If not correctly taken into account, the contamination may have a strong effect on the Initial Mass Function determination and on the identification of quasars. Aims: We calculate in detail the back- and foreground contamination by field dwarfs of very late spectral types (intermediate and late M, L, and T) in deep surveys and provide the data and tools for the computation. Methods: We adopt the latest models and data from the literature, which include the following: (i) a model of the Galactic thin disc by an exponential law; (ii) the length and height scales of late-type dwarfs; and (iii) the local spatial densities, absolute magnitudes, and colours of dwarfs for each spectral type. Results: We derive a simplified expression for the spatial density in the thin disc that depends on the heliocentric distance and the galactic coordinates (l, b) and integrate this into the truncated cone studied in the survey. As a practical application, we compute the numbers of L- and T-type field dwarfs in very deep (I = 21{-}29 mag) surveys in the direction of the young σ Orionis cluster. The increasing number of contaminants at the faintest magnitudes could inhibit the study of the opacity mass limit at M ⪉ 0.003 M_⊙ in the cluster.

  13. UV Variability Selected Active Galactic Nuclei in the GALEX Deep Imaging Survey

    NASA Astrophysics Data System (ADS)

    Gezari, Suvi; Forster, K.; Martin, D. C.; Halpern, J. P.; Neill, J. D.; Huber, M.

    2010-01-01

    We present a sample of active galactic nuclei (AGNs) selected from the UV variability and optical colors and morphology of sources in 7.6 deg2 of the GALEX Deep Imaging Survey matched with the Sloan Digital Sky Survey (SDSS) imaging catalog. We compare yearly co-added epochs of deep GALEX FUV and NUV imaging to measure variability down to deltamag=24. We include spectroscopy for 35% of the sample from the SDSS spectroscopic catalog and from our own spectroscopic follow-up program with the Keck 10m, MDM 2.4m and the APO 3.5m telescopes. In our heterogeneous population of low-luminosity AGNs, Seyferts, and quasars at redshifts ranging from z=0.1 to z=2.0, we detect UV variability amplitudes of up to a factor of 10 on a year timescale, and a ubiquitous trend towards bluer FUV-NUV color during high states of flux. For the first time, we characterize the UV variability properties of a large sample of AGNs with a wide range of luminosities, and compare them to the expectations of accretion disk theory. We also present the exciting capabilities of the GALEX Time Domain Survey, which continuously monitors one of the 7 deg2 Pan-STARRS 1 Medium Deep Survey fields with a cadence of days, and will yield hundreds of AGNs with simultaneous UV and optical light curves.

  14. The DEEP2 Galaxy Redshift Survey: Design, Observations, Data Reduction, and Redshifts

    NASA Astrophysics Data System (ADS)

    Newman, Jeffrey A.; Cooper, Michael C.; Davis, Marc; Faber, S. M.; Coil, Alison L.; Guhathakurta, Puragra; Koo, David C.; Phillips, Andrew C.; Conroy, Charlie; Dutton, Aaron A.; Finkbeiner, Douglas P.; Gerke, Brian F.; Rosario, David J.; Weiner, Benjamin J.; Willmer, C. N. A.; Yan, Renbin; Harker, Justin J.; Kassin, Susan A.; Konidaris, N. P.; Lai, Kamson; Madgwick, Darren S.; Noeske, K. G.; Wirth, Gregory D.; Connolly, A. J.; Kaiser, N.; Kirby, Evan N.; Lemaux, Brian C.; Lin, Lihwai; Lotz, Jennifer M.; Luppino, G. A.; Marinoni, C.; Matthews, Daniel J.; Metevier, Anne; Schiavon, Ricardo P.

    2013-09-01

    We describe the design and data analysis of the DEEP2 Galaxy Redshift Survey, the densest and largest high-precision redshift survey of galaxies at z ~ 1 completed to date. The survey was designed to conduct a comprehensive census of massive galaxies, their properties, environments, and large-scale structure down to absolute magnitude MB = -20 at z ~ 1 via ~90 nights of observation on the Keck telescope. The survey covers an area of 2.8 deg2 divided into four separate fields observed to a limiting apparent magnitude of R AB = 24.1. Objects with z <~ 0.7 are readily identifiable using BRI photometry and rejected in three of the four DEEP2 fields, allowing galaxies with z > 0.7 to be targeted ~2.5 times more efficiently than in a purely magnitude-limited sample. Approximately 60% of eligible targets are chosen for spectroscopy, yielding nearly 53,000 spectra and more than 38,000 reliable redshift measurements. Most of the targets that fail to yield secure redshifts are blue objects that lie beyond z ~ 1.45, where the [O II] 3727 Å doublet lies in the infrared. The DEIMOS 1200 line mm-1 grating used for the survey delivers high spectral resolution (R ~ 6000), accurate and secure redshifts, and unique internal kinematic information. Extensive ancillary data are available in the DEEP2 fields, particularly in the Extended Groth Strip, which has evolved into one of the richest multiwavelength regions on the sky. This paper is intended as a handbook for users of the DEEP2 Data Release 4, which includes all DEEP2 spectra and redshifts, as well as for the DEEP2 DEIMOS data reduction pipelines. Extensive details are provided on object selection, mask design, biases in target selection and redshift measurements, the spec2d two-dimensional data-reduction pipeline, the spec1d automated redshift pipeline, and the zspec visual redshift verification process, along with examples of instrumental signatures or other artifacts that in some cases remain after data reduction. Redshift

  15. The DEEP2 Galaxy Redshift Survey: Design, Observations, Data Reduction, and Redshifts

    NASA Technical Reports Server (NTRS)

    Newman, Jeffrey A.; Cooper, Michael C.; Davis, Marc; Faber, S. M.; Coil, Alison L; Guhathakurta, Puraga; Koo, David C.; Phillips, Andrew C.; Conroy, Charlie; Dutton, Aaron A.; hide

    2013-01-01

    We describe the design and data analysis of the DEEP2 Galaxy Redshift Survey, the densest and largest high-precision redshift survey of galaxies at z approx. 1 completed to date. The survey was designed to conduct a comprehensive census of massive galaxies, their properties, environments, and large-scale structure down to absolute magnitude MB = -20 at z approx. 1 via approx.90 nights of observation on the Keck telescope. The survey covers an area of 2.8 Sq. deg divided into four separate fields observed to a limiting apparent magnitude of R(sub AB) = 24.1. Objects with z approx. < 0.7 are readily identifiable using BRI photometry and rejected in three of the four DEEP2 fields, allowing galaxies with z > 0.7 to be targeted approx. 2.5 times more efficiently than in a purely magnitude-limited sample. Approximately 60% of eligible targets are chosen for spectroscopy, yielding nearly 53,000 spectra and more than 38,000 reliable redshift measurements. Most of the targets that fail to yield secure redshifts are blue objects that lie beyond z approx. 1.45, where the [O ii] 3727 Ang. doublet lies in the infrared. The DEIMOS 1200 line mm(exp -1) grating used for the survey delivers high spectral resolution (R approx. 6000), accurate and secure redshifts, and unique internal kinematic information. Extensive ancillary data are available in the DEEP2 fields, particularly in the Extended Groth Strip, which has evolved into one of the richest multiwavelength regions on the sky. This paper is intended as a handbook for users of the DEEP2 Data Release 4, which includes all DEEP2 spectra and redshifts, as well as for the DEEP2 DEIMOS data reduction pipelines. Extensive details are provided on object selection, mask design, biases in target selection and redshift measurements, the spec2d two-dimensional data-reduction pipeline, the spec1d automated redshift pipeline, and the zspec visual redshift verification process, along with examples of instrumental signatures or other

  16. THE DEEP2 GALAXY REDSHIFT SURVEY: DESIGN, OBSERVATIONS, DATA REDUCTION, AND REDSHIFTS

    SciTech Connect

    Newman, Jeffrey A.; Cooper, Michael C.; Davis, Marc; Faber, S. M.; Guhathakurta, Puragra; Koo, David C.; Phillips, Andrew C.; Conroy, Charlie; Harker, Justin J.; Lai, Kamson; Dutton, Aaron A.; Finkbeiner, Douglas P.; Gerke, Brian F.; Rosario, David J.; Weiner, Benjamin J.; Willmer, C. N. A.; Yan Renbin; Kassin, Susan A.; Konidaris, N. P. E-mail: djm70@pitt.edu E-mail: mdavis@berkeley.edu E-mail: koo@ucolick.org E-mail: phillips@ucolick.org; and others

    2013-09-15

    We describe the design and data analysis of the DEEP2 Galaxy Redshift Survey, the densest and largest high-precision redshift survey of galaxies at z {approx} 1 completed to date. The survey was designed to conduct a comprehensive census of massive galaxies, their properties, environments, and large-scale structure down to absolute magnitude M{sub B} = -20 at z {approx} 1 via {approx}90 nights of observation on the Keck telescope. The survey covers an area of 2.8 deg{sup 2} divided into four separate fields observed to a limiting apparent magnitude of R{sub AB} = 24.1. Objects with z {approx}< 0.7 are readily identifiable using BRI photometry and rejected in three of the four DEEP2 fields, allowing galaxies with z > 0.7 to be targeted {approx}2.5 times more efficiently than in a purely magnitude-limited sample. Approximately 60% of eligible targets are chosen for spectroscopy, yielding nearly 53,000 spectra and more than 38,000 reliable redshift measurements. Most of the targets that fail to yield secure redshifts are blue objects that lie beyond z {approx} 1.45, where the [O II] 3727 A doublet lies in the infrared. The DEIMOS 1200 line mm{sup -1} grating used for the survey delivers high spectral resolution (R {approx} 6000), accurate and secure redshifts, and unique internal kinematic information. Extensive ancillary data are available in the DEEP2 fields, particularly in the Extended Groth Strip, which has evolved into one of the richest multiwavelength regions on the sky. This paper is intended as a handbook for users of the DEEP2 Data Release 4, which includes all DEEP2 spectra and redshifts, as well as for the DEEP2 DEIMOS data reduction pipelines. Extensive details are provided on object selection, mask design, biases in target selection and redshift measurements, the spec2d two-dimensional data-reduction pipeline, the spec1d automated redshift pipeline, and the zspec visual redshift verification process, along with examples of instrumental signatures or

  17. Deep X-ray and UV Surveys of Galaxies with Chandra, XMM-Newton, and GALEX

    NASA Technical Reports Server (NTRS)

    Hornschemeier, Ann

    2006-01-01

    Only with the deepest Chandra surveys has X-ray emission from normal and star forming galaxies (as opposed to AGN, which dominate the X-ray sky) been accessible at cosmologically interesting distances. The X-ray emission from accreting binaries provide a critical glimpse into the binary phase of stellar evolution and studies of the hot gas reservoir constrain past star formation. UV studies provide important, sensitive diagnostics of the young star forming populations and provide the most mature means for studying galaxies at 2 < zeta < 4. This talk will review current progress on studying X-ray emission in concert with UV emission from normal/star-forming galaxies at higher redshift. We will also report on our new, deep surveys with GALEX and XMM-Newton in the nearby Coma cluster. These studies are relevant to DEEP06 as Coma is the nearest rich cluster of galaxies and provides an important benchmark for high-redshift studies in the X-ray and UV wavebands. The 30 ks GALEX (note: similar depth to the GALEX Deep Imaging Survey) and the 110 ks XMM observations provide extremely deep coverage of a Coma outskirts field, allowing the construction of the UV and X-ray luminosity function of galaxies and important constraints on star formation scaling relations such as the X-ray-Star Formation Rate correlation and the X-ray/Stellar Mass correlation. We will discuss what we learn from these deep observations of Coma, including the recently established suppression of the X-ray emission from galaxies in the Coma outskirts that is likely associated with lower levels of past star formation and/or the results of tidal gas stripping.

  18. Deep X-ray and UV Surveys of Galaxies with Chandra, XMM-Newton, and GALEX

    NASA Technical Reports Server (NTRS)

    Hornschemeier, Ann

    2006-01-01

    Only with the deepest Chandra surveys has X-ray emission from normal and star forming galaxies (as opposed to AGN, which dominate the X-ray sky) been accessible at cosmologically interesting distances. The X-ray emission from accreting binaries provide a critical glimpse into the binary phase of stellar evolution and studies of the hot gas reservoir constrain past star formation. UV studies provide important, sensitive diagnostics of the young star forming populations and provide the most mature means for studying galaxies at 2 < zeta < 4. This talk will review current progress on studying X-ray emission in concert with UV emission from normal/star-forming galaxies at higher redshift. We will also report on our new, deep surveys with GALEX and XMM-Newton in the nearby Coma cluster. These studies are relevant to DEEP06 as Coma is the nearest rich cluster of galaxies and provides an important benchmark for high-redshift studies in the X-ray and UV wavebands. The 30 ks GALEX (note: similar depth to the GALEX Deep Imaging Survey) and the 110 ks XMM observations provide extremely deep coverage of a Coma outskirts field, allowing the construction of the UV and X-ray luminosity function of galaxies and important constraints on star formation scaling relations such as the X-ray-Star Formation Rate correlation and the X-ray/Stellar Mass correlation. We will discuss what we learn from these deep observations of Coma, including the recently established suppression of the X-ray emission from galaxies in the Coma outskirts that is likely associated with lower levels of past star formation and/or the results of tidal gas stripping.

  19. Deep 2mm Surveys with GISMO : Searching for submillimeter galaxies at the highest redshifts

    NASA Astrophysics Data System (ADS)

    Staguhn, Johannes Gunter; Kovacs, Attila; Karim, Alexander; Arendt, Richard; Benford, Dominic J.; Decarli, Roberto; Dwek, Eli; Fixsen, Dale; Gene, Hilton; Irwin, Kent; Moseley, S. Harvey; Sharp, Elmer; Walter, Fabian; Edward, Wollack

    2015-08-01

    The GISMO 2 mm camera at the IRAM 30m telescope has been available to the astronomical community for years through the semi-annual IRAM call for proposals. The 2 mm band is in particular well suited to trace the first dusty galaxies in the universe, since their redshifted SEDs peak close to GISMO's observing frequency, whereas the medium redshift galaxy foreground is almost invisible in this band. This effect makes GISMO's deep field observations a valuable complement, rather than a redundancy, to the HERSCHEL far-infrared and sub-mm surveys. Two survey projects aiming at obtaining 2mm galaxy number counts are at the core of GISMO’s science. Simple models predict an appreciable number of galaxies detected in these surveys to be be at very high redshifts (z~5-6 and above) with intrinsic luminosities of a few 10^12 L_sol.The first of these projects is the GISMO Deep Field (GDF) survey, which is centered on the Hubble Deep Field North. This survey by now has reached the confusion limit (we measure a confusion noise of 60 microJy). Our detailed statistical analysis of the GDF data provides a solid estimate of the expected rate of false detections among those source identifications. Furthermore, numerical simulations were used, to estimate the "completeness" of our set of extracted sources. A comparison of our observations with model predictions shows that our results are in good agreement with galaxy count models.The second survey covers a ~ 1/4 square degree region in the COSMOS field, in which by now we have obtained sufficient sensitivity to extract statistically relevant galaxy number counts, and by using auxiliary data, redshift distributions. We will present first results that complement those obtained in the deeper GDF.

  20. THE DEEP3 GALAXY REDSHIFT SURVEY: KECK/DEIMOS SPECTROSCOPY IN THE GOODS-N FIELD

    SciTech Connect

    Cooper, Michael C.; Aird, James A.; Coil, Alison L. E-mail: acoil@ucsd.edu

    2011-03-15

    We present the results of spectroscopic observations in the GOODS-N field completed using DEIMOS on the Keck II telescope as part of the DEEP3 Galaxy Redshift Survey. Observations of 370 unique targets down to a limiting magnitude of R {sub AB} = 24.4 yielded 156 secure redshifts. In addition to redshift information, we provide sky-subtracted one- and two-dimensional spectra of each target. Observations were conducted following the procedures of the Team Keck Redshift Survey (TKRS), thereby producing spectra that augment the TKRS sample while maintaining the uniformity of its spectral database.

  1. Cathodic protection survey of deep-water structures and subsea installations

    SciTech Connect

    Leask, L.J. )

    1989-11-01

    The successful and efficient cathodic protection (CP) survey of a deep water structure using a remotely operated vehicle (ROV) has remained an enigma to many corrosion engineers in oil companies. The location of the corrosion group within the company structure often plays a major role in the success of the project. Operators locate their corrosion departments in different groups, some in the offshore/onshore operations and others in the design group. This location often has a bearing on the financial and operational approach to the project. The author discusses how a successful CP survey is both an achievable and exciting project with experienced preplanning and selection of the correct equipment.

  2. CP survey of deep water structures and subsea installations using an ROV

    SciTech Connect

    Leask, L.J. )

    1989-01-01

    The successful and efficient CP survey of a deep water structure using a remotely operated vehicle (ROV) has remained an enigma to many corrosion engineers in oil companies. The location of the corrosion group within the company structure often plays a major role in the success of the project. Operators locate their corrosion departments in different groups, some in the offshore/onshore operations and others in the design group. This location often has a bearing on the financial and operational approach to the project. This paper discusses how a successful CP survey is both an achievable and exciting project with experienced pre- planning and selection of the correct equipment.

  3. A Dataset of Deep-Sea Fishes Surveyed by Research Vessels in the Waters around Taiwan

    PubMed Central

    Shao, Kwang-Tsao; Lin, Jack; Yeh, Hsin-Ming; Lee, Mao-Yin; Chen, Lee-Sea; Lin, Hen-Wei

    2014-01-01

    Abstract The study of deep-sea fish fauna is hampered by a lack of data due to the difficulty and high cost incurred in its surveys and collections. Taiwan is situated along the edge of the Eurasia fig, at the junction of three Large Marine Ecosystems or Ecoregions of the East China Sea, South China Sea and the Philippines. As nearly two-thirds of its surrounding marine ecosystems are deep-sea environments, Taiwan is expected to hold a rich diversity of deep-sea fish. However, in the past, no research vessels were employed to collect fish data on site. Only specimens, caught by bottom trawl fishing in the waters hundreds of meters deep and missing precise locality information, were collected from Dasi and Donggang fishing harbors. Began in 2001, with the support of National Science Council, research vessels were made available to take on the task of systematically collecting deep-sea fish specimens and occurrence records in the waters surrounding Taiwan. By the end of 2006, a total of 3,653 specimens, belonging to 26 orders, 88 families, 198 genera and 366 species, were collected in addition to data such as sampling site geographical coordinates and water depth, and fish body length and weight. The information, all accessible from the “Database of Taiwan’s Deep-Sea Fauna and Its Distribution (http://deepsea.biodiv.tw/)” as part of the “Fish Database of Taiwan,” can benefit the study of temporal and spatial changes in distribution and abundance of fish fauna in the context of global deep-sea biodiversity. PMID:25610339

  4. A Dataset of Deep-Sea Fishes Surveyed by Research Vessels in the Waters around Taiwan.

    PubMed

    Shao, Kwang-Tsao; Lin, Jack; Yeh, Hsin-Ming; Lee, Mao-Yin; Chen, Lee-Sea; Lin, Hen-Wei

    2014-01-01

    The study of deep-sea fish fauna is hampered by a lack of data due to the difficulty and high cost incurred in its surveys and collections. Taiwan is situated along the edge of the Eurasia fig, at the junction of three Large Marine Ecosystems or Ecoregions of the East China Sea, South China Sea and the Philippines. As nearly two-thirds of its surrounding marine ecosystems are deep-sea environments, Taiwan is expected to hold a rich diversity of deep-sea fish. However, in the past, no research vessels were employed to collect fish data on site. Only specimens, caught by bottom trawl fishing in the waters hundreds of meters deep and missing precise locality information, were collected from Dasi and Donggang fishing harbors. Began in 2001, with the support of National Science Council, research vessels were made available to take on the task of systematically collecting deep-sea fish specimens and occurrence records in the waters surrounding Taiwan. By the end of 2006, a total of 3,653 specimens, belonging to 26 orders, 88 families, 198 genera and 366 species, were collected in addition to data such as sampling site geographical coordinates and water depth, and fish body length and weight. The information, all accessible from the "Database of Taiwan's Deep-Sea Fauna and Its Distribution (http://deepsea.biodiv.tw/)" as part of the "Fish Database of Taiwan," can benefit the study of temporal and spatial changes in distribution and abundance of fish fauna in the context of global deep-sea biodiversity.

  5. The most distant galaxy clusters in the SPT Spitzer Deep Field Survey

    NASA Astrophysics Data System (ADS)

    Rettura, Alessandro; Stanford, S. A.; Stern, D.; Mei, S.; Brodwin, M.; Gonzalez, A. H.; Gettings, D.; Ashby, M.; Bartlett, J.; Rosati, P.

    2014-01-01

    We present a sample of more than 300 galaxy cluster candidates at z>1.3 selected within 94 deg2 from the Spitzer SPT Deep Field (SSDF) survey. To discover distant clusters at z>1.3, we have used a three-filter algorithm based upon Spitzer/IRAC color ([3.6]-[4.5]>-0.1,AB) combined with a non-detection in shallow optical data. Our sample is selected to be a complete stellar mass-limited sample at z>1.3 and therefore has a well defined survey volume. The uniqueness of SSDF resides not just in its area, one of the very largest with Spitzer, but also in its coverage by deep observations for the Sunyaev-Zel'dovich (SZ) effect with the South Pole Telescope (SPT). Deeper observations are also planned with the new SPT camera, SPTpol, that will reach, for the first time, SZ clusters up to 2 (George et al., 2012). This field also has deep X-ray observations from the XMM XXL Survey (Pierre et al., 2012). Thanks to this rich data set, we will be able to determine accurate cluster masses for the vast majority of our SSDF clusters at 1.3

  6. CANDELS: The Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey

    NASA Technical Reports Server (NTRS)

    Grogin, Norman A.; Koekemoer, anton M.; Faber, S. M.; Ferguson, Henry C.; Kocevski, Dale D.; Riess, Adam G.; Acquaviva, Viviana; Alexander, David M.; Almaini, Omar; Ashby, Matthew L. N.; Barden, Marco; Bell, Eric F.; Bournaud, Frederic; Brown, Thomas M.; Caputi, Karina I.; Casertano, Stefano; Cassata, Paolo; Challis, Peter; Chary, Ranga-Ram; Cheung, Edmond; Cirasuolo, Michele; DeMello, Duilla; Gardner, Jonathan P.; Straughn, Amber N.

    2011-01-01

    The Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS) is designed to document the first third of galactic evolution, from z approx. 8 - 1.5. It will image > 250,000 distant galaxies using three separate cameras on the Hubble Space Tele8cope, from the mid-UV to near-IR, and will find and measure Type Ia supernovae beyond z > 1.5 to test their accuracy as standard candles for cosmology. Five premier multi-wavelength sky regions are selected, each with extensive ancillary data. The use of five widely separated fields mitigates cosmic variance and yields statistically robust and complete samples of galaxies down to a stellar mass of 10(exp 9) solar mass to z approx. 2, reaching the knee of the UV luminosity function of galaxies to z approx. 8. The survey covers approximately 800 square arc minutes and is divided into two parts. The CANDELS/Deep survey (5(sigma) point-source limit H =27.7mag) covers approx. 125 square arcminutes within GOODS-N and GOODS-S. The CANDELS/Wide survey includes GOODS and three additional fields (EGS, COSMOS, and UDS) and covers the full area to a 50(sigma) point-source limit of H ? or approx. = 27.0 mag. Together with the Hubble Ultradeep Fields, the strategy creates a three-tiered "wedding cake" approach that has proven efficient for extragalactic surveys. Data from the survey are non-proprietary and are useful for a wide variety of science investigations. In this paper, we describe the basic motivations for the survey, the CANDELS team science goals and the resulting observational requirements, the field selection and geometry, and the observing design.

  7. International Deep Planet Survey, 317 stars to determine the wide-separated planet frequency

    NASA Astrophysics Data System (ADS)

    Galicher, R.; Marois, C.; Macintosh, B.; Zuckerman, B.; Song, I.; Barman, T.; Patience, J.

    2013-09-01

    Since 2000, more than 300 nearby young stars were observed for the International Deep Planet Survey with adaptive optics systems at Gemini (NIRI/NICI), Keck (Nirc2), and VLT (Naco). Massive young AF stars were included in our sample whereas they have generally been neglected in first generation surveys because the contrast and target distances are less favorable to image substellar companions. The most significant discovery of the campaign is the now well-known HR 8799 multi-planet system. This remarkable finding allows, for the first time, an estimate of the Jovians planet population at large separations (further than a few AUs) instead of deriving upper limits. During my presentation, I will present the survey showing images of multiple stars and planets. I will then propose a statistic study of the observed stars deriving constraints on the Jupiter-like planet frequency at large separations.

  8. The CfA Einstein Observatory extended deep X-ray survey

    NASA Technical Reports Server (NTRS)

    Primini, F. A.; Murray, S. S.; Huchra, J.; Schild, R.; Burg, R.

    1991-01-01

    All IPC exposures in the Einstein Extended Deep X-ray Survey program have been reanalyzed. The current survey covers about 2.3 sq deg with a typical limiting sensitivity of about 5 x 10 to the -14th ergs/sq cm/s in the energy range from 0.8-3.5 keV. A total of 25 IPC sources are detected above a threshold of 4.5 sigma. A total of 18 are detected independently in the HRI, leading to the identification of six with stars and 11 with extragalactic objects. The remaining sources are classified as extragalactic. The population of identified extragalactic objects is dominated by QSOs, with one or two possible clusters. The basic conclusions of the original survey remain unchanged.

  9. The infrared medium-deep survey. II. How to trigger radio AGNs? Hints from their environments

    SciTech Connect

    Karouzos, Marios; Im, Myungshin; Kim, Jae-Woo; Lee, Seong-Kook; Jeon, Yiseul; Choi, Changsu; Hong, Jueun; Hyun, Minhee; Jun, Hyunsung David; Kim, Dohyeong; Kim, Yongjung; Kim, Ji Hoon; Kim, Duho; Park, Won-Kee; Taak, Yoon Chan; Yoon, Yongmin; Chapman, Scott; Pak, Soojong; Edge, Alastair

    2014-12-10

    Activity at the centers of galaxies, during which the central supermassive black hole is accreting material, is nowadays accepted to be rather ubiquitous and most probably a phase of every galaxy's evolution. It has been suggested that galactic mergers and interactions may be the culprits behind the triggering of nuclear activity. We use near-infrared data from the new Infrared Medium-Deep Survey and the Deep eXtragalactic Survey of the VIMOS-SA22 field and radio data at 1.4 GHz from the FIRST survey and a deep Very Large Array survey to study the environments of radio active galactic nuclei (AGNs) over an area of ∼25 deg{sup 2} and down to a radio flux limit of 0.1 mJy and a J-band magnitude of 23 mag AB. Radio AGNs are predominantly found in environments similar to those of control galaxies at similar redshift, J-band magnitude, and (M{sub u} – M{sub r} ) rest-frame color. However, a subpopulation of radio AGNs is found in environments up to 100 times denser than their control sources. We thus preclude merging as the dominant triggering mechanism of radio AGNs. By fitting the broadband spectral energy distribution of radio AGNs in the least and most dense environments, we find that those in the least dense environments show higher radio-loudness, higher star formation efficiencies, and higher accretion rates, typical of the so-called high-excitation radio AGNs. These differences tend to disappear at z > 1. We interpret our results in terms of a different triggering mechanism for these sources that is driven by mass loss through winds of young stars created during the observed ongoing star formation.

  10. Optical Survey with KMTNet for Dusty Star-Forming Galaxies in the Akari Deep Field South

    NASA Astrophysics Data System (ADS)

    Jeong, Woong-Seob; Ko, Kyeongyeon; Kim, Minjin; Ko, Jongwan; Kim, Sam; Pyo, Jeonghyun; Kim, Seong Jin; Kim, Taehyun; Seo, Hyun Jong; Park, Won-Kee; Park, Sung-Joon; Kim, Min Gyu; Kim, Dong Jin; Cha, Sang-Mok; Lee, Yongseok; Lee, Chung-Uk; Kim, Seung-Lee; Matsuura, Shuji; Pearson, Chris; Matsuhara, Hideo

    2016-10-01

    We present an optical imaging survey of AKARI Deep Field South (ADF-S) using the Korea Microlensing Telescope Network (KMTNet), to find optical counterparts of dusty star-forming galaxies. The ADF-S is a deep far-infrared imaging survey region with AKARI covering around 12 deg^2, where the deep optical imaging data are not yet available. By utilizing the wide-field capability of the KMTNet telescopes (˜4 deg^2), we obtain optical images in B, R and I bands for three regions. The target depth of images in B, R and I bands is ˜24 mag (AB) at 5σ, which enables us to detect most dusty star-forming galaxies discovered by AKARI in the ADF-S. Those optical datasets will be helpful to constrain optical spectral energy distributions as well as to identify rare types of dusty star-forming galaxies such as dust-obscured galaxy, sub-millimeter galaxy at high redshift.}

  11. Dentists' attitudes and behaviour regarding deep carious lesion management: a multi-national survey.

    PubMed

    Schwendicke, Falk; Stangvaltaite, Lina; Holmgren, Christopher; Maltz, Marisa; Finet, Marion; Elhennawy, Karim; Eriksen, Isabel; Kuzmiszyn, Tone Christiansen; Kerosuo, Eero; Doméjean, Sophie

    2017-01-01

    The present study aimed, using a questionnaire, to assess and compare behaviour, attitudes and beliefs of French, German and Norwegian dentists regarding deep carious lesion management. A mail survey was applied to simple random national samples of dentists. Descriptive analysis and logistic regression analysis were performed. Sample size was 661 (response rate, 33 %) in France, 622 (25 %) in Germany and 199 (33 %) in Norway. Hardness was the criterion used most often for assessing carious tissue removal in all three countries (>95 %), with most dentists aiming for only hard dentine remaining at the pulpal wall (>66 %); dentine colour was not found relevant by most respondents. The majority of French and German practitioners (>66 %) would perform complete excavation even for deep lesions, while most Norwegian dentists (84 %) opted for stepwise excavation. Most dentists thought complete removal was required to avoid lesion progression and were uncertain if remaining sealed bacteria would harm the pulp. Treatment decisions were guided by prior experience and familiarity. For example, stepwise removal was performed less often by dentists who were male, French, German or those in the private sector. Less invasive strategies for managing deep lesions have not widely entered clinical practice in France and Germany. Underlying beliefs shape decision-making. The present study is the first of its nature to analyse and compare deep carious lesion management between three European countries. It shows that there is an urgent need to practically educate dentists in less invasive strategies.

  12. VizieR Online Data Catalog: LESS photometric redshift survey (Wardlow+, 2011)

    NASA Astrophysics Data System (ADS)

    Wardlow, J. L.; Smail, I.; Coppin, K. E. K.; Alexander, D. M.; Brandt, W. N.; Danielson, A. L. R.; Luo, B.; Swinbank, A. M.; Walter, F.; Weiss, A.; Xue, Y. Q.; Zibetti, S.; Bertoldi, F.; Biggs, A. D.; Chapman, S. C.; Dannerbauer, H.; Dunlop, J. S.; Gawiser, E.; Ivison, R. J.; Knudsen, K. K.; Kovacs, A.; Lacey, C. G.; Menten, K. M.; Padilla, N.; Rix, H.-W.; van der Werf, P. P.

    2012-02-01

    SMGs typically have faint optical and near-IR counterparts (e.g. Ivison et al. 2002MNRAS.337....1I), so we require deep photometry for accurate photometric redshift estimates. The ECDF-S was chosen for this survey because it is an exceptionally well-studied field and as such we are able to utilize data from extensive archival imaging and spectroscopic surveys. For completeness and uniformity, we only consider surveys that cover a large fraction of the ECDF-S rather than the smaller and deeper central Chandra Deep Field-South (CDF-S) region. Therefore, we utilize the MUltiwavelength Survey by Yale-Chile (MUSYC; Gawiser et al. 2006, Cat. J/ApJS/162/1) near-IR survey for U- to K-band imaging (Taylor et al. 2009, Cat. J/ApJS/183/295), and the Spitzer IRAC/MUSYC Public Legacy in ECDF-S (SIMPLE) imaging for Spitzer IRAC data (Damen et al. 2011, cat. J/ApJ/727/1). We also include U-band data from the deep GOODS/VIMOS imaging survey of the CDF-S (Nonino et al. 2009ApJS..183..244N); although this covers only ~60 per cent of LESS SMGs, it is valuable for galaxies that are undetected at short wavelengths in the shallower MUSYC survey. In addition, we have carried out deep near-IR observations in the J and Ks bands with the HAWK-I at the ESO-VLT (ID: 082.A-0890, PI: N. Padilla). (2 data files).

  13. THE DEEP2 GALAXY REDSHIFT SURVEY: THE VORONOI-DELAUNAY METHOD CATALOG OF GALAXY GROUPS

    SciTech Connect

    Gerke, Brian F.; Newman, Jeffrey A.; Davis, Marc; Coil, Alison L.; Cooper, Michael C.; Dutton, Aaron A.; Faber, S. M.; Guhathakurta, Puragra; Koo, David C.; Phillips, Andrew C.; Noeske, Kai; Rosario, David J.; Weiner, Benjamin J.; Willmer, Christopher N. A.; Yan, Renbin

    2012-05-20

    We present a public catalog of galaxy groups constructed from the spectroscopic sample of galaxies in the fourth data release from the Deep Extragalactic Evolutionary Probe 2 (DEEP2) Galaxy Redshift Survey, including the Extended Groth Strip (EGS). The catalog contains 1165 groups with two or more members in the EGS over the redshift range 0 < z < 1.5 and 1295 groups at z > 0.6 in the rest of DEEP2. Twenty-five percent of EGS galaxies and fourteen percent of high-z DEEP2 galaxies are assigned to galaxy groups. The groups were detected using the Voronoi-Delaunay method (VDM) after it has been optimized on mock DEEP2 catalogs following similar methods to those employed in Gerke et al. In the optimization effort, we have taken particular care to ensure that the mock catalogs resemble the data as closely as possible, and we have fine-tuned our methods separately on mocks constructed for the EGS and the rest of DEEP2. We have also probed the effect of the assumed cosmology on our inferred group-finding efficiency by performing our optimization on three different mock catalogs with different background cosmologies, finding large differences in the group-finding success we can achieve for these different mocks. Using the mock catalog whose background cosmology is most consistent with current data, we estimate that the DEEP2 group catalog is 72% complete and 61% pure (74% and 67% for the EGS) and that the group finder correctly classifies 70% of galaxies that truly belong to groups, with an additional 46% of interloper galaxies contaminating the catalog (66% and 43% for the EGS). We also confirm that the VDM catalog reconstructs the abundance of galaxy groups with velocity dispersions above {approx}300 km s{sup -1} to an accuracy better than the sample variance, and this successful reconstruction is not strongly dependent on cosmology. This makes the DEEP2 group catalog a promising probe of the growth of cosmic structure that can potentially be used for cosmological tests.

  14. The DEEP2 Galaxy Redshift Survey: The Voronoi-Delaunay Method Catalog of Galaxy Groups

    SciTech Connect

    Gerke, Brian F.; Newman, Jeffrey A.; Davis, Marc; Marinoni, Christian; Yan, Renbin; Coil, Alison L.; Conroy, Charlie; Cooper, Michael C.; Faber, S.M.; Finkbeiner, Douglas P.; Guhathakurta, Puragra; Kaiser, Nick; Koo, David C.; Phillips, Andrew C.; Weiner, Benjamin J.; /Maryland U.

    2012-02-14

    We use the first 25% of the DEEP2 Galaxy Redshift Survey spectroscopic data to identify groups and clusters of galaxies in redshift space. The data set contains 8370 galaxies with confirmed redshifts in the range 0.7 {<=} z {<=} 1.4, over one square degree on the sky. Groups are identified using an algorithm (the Voronoi-Delaunay Method) that has been shown to accurately reproduce the statistics of groups in simulated DEEP2-like samples. We optimize this algorithm for the DEEP2 survey by applying it to realistic mock galaxy catalogs and assessing the results using a stringent set of criteria for measuring group-finding success, which we develop and describe in detail here. We find in particular that the group-finder can successfully identify {approx}78% of real groups and that {approx}79% of the galaxies that are true members of groups can be identified as such. Conversely, we estimate that {approx}55% of the groups we find can be definitively identified with real groups and that {approx}46% of the galaxies we place into groups are interloper field galaxies. Most importantly, we find that it is possible to measure the distribution of groups in redshift and velocity dispersion, n({sigma}, z), to an accuracy limited by cosmic variance, for dispersions greater than 350 km s{sup -1}. We anticipate that such measurements will allow strong constraints to be placed on the equation of state of the dark energy in the future. Finally, we present the first DEEP2 group catalog, which assigns 32% of the galaxies to 899 distinct groups with two or more members, 153 of which have velocity dispersions above 350 km s{sup -1}. We provide locations, redshifts and properties for this high-dispersion subsample. This catalog represents the largest sample to date of spectroscopically detected groups at z {approx} 1.

  15. Theoretical Models of a Flare on AU MIC seen by EUVE Deep Survey Detectors

    NASA Astrophysics Data System (ADS)

    Fisher, George H.; Cully, Scott L.; Siegmund, O. H. W.

    1993-05-01

    The M-dwarf star AU Mic was observed by the EUVE Deep Survey Instrument from 1992 July 14-18. A large flare with a total radiated energy in the EUV of approximately 3 times 10(34) \\ erg was detected in the Lexan/Boron (65-190 Angstroms) band at 12:38 UT on 15 July 1992. These observations are described further in a recent paper (Cully, Siegmund, Vedder and Vallerga Ap. J. Lett, 1993, in press). We present an analysis of this data in terms of theoretical models of flaring loops.

  16. VizieR Online Data Catalog: A deep Chandra ACIS survey of M51 (Kuntz+, 2016)

    NASA Astrophysics Data System (ADS)

    Kuntz, K. D.; Long, K. S.; Kilgard, R. E.

    2016-11-01

    This deep study of M51 is composed of 107ks of archival Chandra observations, to which we have added another 745ks of observations. All of the observations were made with the ACIS-S array. M51 has been observed extensively with HST. In particular, essentially all of M51 and its companion NGC 5195 was imaged with Advanced Camera for Surveys (ACS) in V, R, and I (F435W, F555W, F814W) and Hα (F658N) as a Hubble Legacy Project (Proposal ID 10452, PI: S. Beckwith). (4 data files).

  17. The Spitzer South Pole Telescope Deep Field: Survey Design and Infrared Array Camera Catalogs

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

    The Spitzer South Pole Telescope Deep Field (SSDF) is a wide-area survey using Spitzer's Infrared Array Camera (IRAC) to cover 94 deg2 of extragalactic sky, making it the largest IRAC survey completed to date outside the Milky Way midplane. The SSDF is centered at (α, δ) = (23:30, -55:00), in a region that combines observations spanning a broad wavelength range from numerous facilities. These include millimeter imaging from the South Pole Telescope, far-infrared observations from Herschel/SPIRE, X-ray observations from the XMM XXL survey, near-infrared observations from the VISTA Hemisphere Survey, and radio-wavelength imaging from the Australia Telescope Compact Array, in a panchromatic project designed to address major outstanding questions surrounding galaxy clusters and the baryon budget. Here we describe the Spitzer/IRAC observations of the SSDF, including the survey design, observations, processing, source extraction, and publicly available data products. In particular, we present two band-merged catalogs, one for each of the two warm IRAC selection bands. They contain roughly 5.5 and 3.7 million distinct sources, the vast majority of which are galaxies, down to the SSDF 5σ sensitivity limits of 19.0 and 18.2 Vega mag (7.0 and 9.4 μJy) at 3.6 and 4.5 μm, respectively.

  18. DEEP GALEX UV SURVEY OF THE KEPLER FIELD. I. POINT SOURCE CATALOG

    SciTech Connect

    Olmedo, Manuel; Chávez, Miguel; Bertone, Emanuele; Lloyd, James; Mamajek, Eric E.; Martin, D. Christopher; Neill, James D.

    2015-11-10

    We report observations of a deep near-ultraviolet (NUV) survey of the Kepler field made in 2012 with the Galaxy Evolution Explorer (GALEX) Complete All-Sky UV Survey Extension (CAUSE). The GALEX-CAUSE Kepler survey (GCK) covers 104 square degrees of the Kepler field and reaches a limiting magnitude of NUV ≃ 22.6 at 3σ. Analysis of the GCK survey has yielded a catalog of 669,928 NUV sources, of which 475,164 are cross-matched with stars in the Kepler Input Catalog. Approximately 327 of 451 confirmed exoplanet host stars and 2614 of 4696 candidate exoplanet host stars identified by Kepler have NUV photometry in the GCK survey. The GCK catalog should enable the identification and characterization of UV-excess stars in the Kepler field (young solar-type and low-mass stars, chromospherically active binaries, white dwarfs, horizontal branch stars, etc.), and elucidation of various astrophysics problems related to the stars and planetary systems in the Kepler field.

  19. Calculating Proper Motions in the WFCAM Science Archive for the UKIRT Infrared Deep Sky Surveys

    NASA Astrophysics Data System (ADS)

    Collins, R.; Hambly, N.

    2012-09-01

    The ninth data release from the UKIRT Infrared Deep Sky Surveys (hereafter UKIDSS DR9), represents five years worth of observations by its wide-field camera (WFCAM) and will be the first to include proper motion values in its source catalogues for the shallow, wide-area surveys; the Large Area Survey (LAS), Galactic Clusters Survey (GCS) and (ultimately) Galactic Plane Survey (GPS). We, the Wide Field Astronomy Unit (WFAU) at the University of Edinburgh who prepare these regular data releases in the WFCAM Science Archive (WSA), describe in this paper how we make optimal use of the individual detection catalogues from each observation to derive high-quality astrometric fits for the positions of each detection enabling us to calculate a proper motion solution across multiple epochs and passbands when constructing a merged source catalogue. We also describe how the proper motion solutions affect the calculation of the various attributes provided in the database source catalogue tables, what measures of data quality we provide and a demonstration of the results for observations of the Pleiades cluster.

  20. Constraints on the Number of Kuiper Belt Objects from the Deep Ecliptic Survey

    NASA Astrophysics Data System (ADS)

    Adams, Elisabeth R.; Elliot, J. L.; Kern, S. D.; Gulbis, A. A.; Buie, M. W.; Trilling, D. E.; Wasserman, L. H.

    2007-10-01

    The Deep Ecliptic Survey, or DES, was a systematic survey for Kuiper Belt Objects with primary observations from 1998-2005. Over 800 square degrees of the sky were surveyed, and the DES found roughly 40% of the 1200 objects with preliminary designations from the Minor Planet Center at the time of survey completion. By correcting the survey data for observational bias, we have calculated the probability of discovering each individual object. The probablities range from a high value of 0.38 for 2002PO149 (a Classical object -- see Elliot et al. 2005, Astron. J. 129, 1117 for definitions of the DES dynamical classes) to a low value of 2 x 10^-6 for 82158 (a Scattered Near object). From these probabilities, we can estimate the relative populations of different dynamical classes of objects, provided there are a sufficient number of objects in the class. A few dynamical classes, such as Classical and 3:2 Resonant objects, have enough members for relatively robust statistics, and we estimate the size distributions. We also compare the ratio of objects in different classes to theoretical predictions (Hahn & Malhotra 2005, Astron. J. 130, 2392), based on Neptune migration models. This work was supported, in part, by NSF Grants AST0406493 and AST0707609.

  1. A very deep IRAS survey - Constraints on the evolution of starburst galaxies

    NASA Astrophysics Data System (ADS)

    Hacking, Perry; Condon, J. J.; Houck, J. R.

    1987-05-01

    Counts of sources (primarily starburst galaxies) from a deep 60 microns IRAS survey published by Hacking and Houck (1987) are compared with four evolutionary models. The counts below 100 mJy are higher than expected if no evolution has taken place out to a redshift of approximately 0.2. Redshift measurements of the survey sources should be able to distinguish between luminosity-evolution and density-evolution models and detect as little as a 20 percent brightening or increase in density of infrared sources per billion years ago (H/0/ = 100 km/s per Mpc). Starburst galaxies cannot account for the reported 100 microns background without extreme evolution at high redshifts.

  2. Very deep IRAS survey - constraints on the evolution of starburst galaxies

    SciTech Connect

    Hacking, P.; Houck, J.R.; Condon, J.J.

    1987-05-01

    Counts of sources (primarily starburst galaxies) from a deep 60 microns IRAS survey published by Hacking and Houck (1987) are compared with four evolutionary models. The counts below 100 mJy are higher than expected if no evolution has taken place out to a redshift of approximately 0.2. Redshift measurements of the survey sources should be able to distinguish between luminosity-evolution and density-evolution models and detect as little as a 20 percent brightening or increase in density of infrared sources per billion years ago (H/0/ = 100 km/s per Mpc). Starburst galaxies cannot account for the reported 100 microns background without extreme evolution at high redshifts. 21 references.

  3. The Great Observatories Origins Deep Survey High Redshift Search for Supernovae

    NASA Astrophysics Data System (ADS)

    Strolger, L.-G.; Riess, A. G.; Dahlen, T.; GOODS SN Searchers; HHZS Team

    2003-05-01

    We have recently concluded the Hubble Higher-z Supernova Team's search for high redshift supernovae in conjunction with the Great Observatories Origins Deep Survey (GOODS). Using the Advanced Camera for Surveys (ACS), we have surveyed ˜170 sq. arcmin fields about the CDF-S and HSF-N on five epochs each, with ˜45 day baselines. These deep observations have allowed us to discover ˜40 supernovae in the range of 0.2survey, we will report elsewhere (Riess et al 2003; in preparation) a direct test of this measurement by looking for cosmic deceleration at z>=1. A cosmic evolution of SN Ia luminosity or ``grey dust'' would cause SNe Ia to be systematically fainter at higher-z and thus show a different sign and shape on the Hubble diagram. We are also investigating the rate of SNe at /line{z}˜=0.8-1.0, the relation to the local rates, comparisons of host environments to low redshift host environments, and the implications of each to SN progenitors, star formation rate history, and possibly to cosmology.

  4. When is stacking confusing? The impact of confusion on stacking in deep H I galaxy surveys

    NASA Astrophysics Data System (ADS)

    Jones, Michael G.; Haynes, Martha P.; Giovanelli, Riccardo; Papastergis, Emmanouil

    2016-01-01

    We present an analytic model to predict the H I mass contributed by confused sources to a stacked spectrum in a generic H I survey. Based on the ALFALFA (Arecibo Legacy Fast ALFA) correlation function, this model is in agreement with the estimates of confusion present in stacked Parkes telescope data, and was used to predict how confusion will limit stacking in the deepest Square Kilometre Array precursor H I surveys. Stacking with LADUMA (Looking At the Distant Universe with MeerKAT) and DINGO UDEEP (Deep Investigation of Neutral Gas Origins - Ultra Deep) data will only be mildly impacted by confusion if their target synthesized beam size of 10 arcsec can be achieved. Any beam size significantly above this will result in stacks that contain a mass in confused sources that is comparable to (or greater than) that which is detectable via stacking, at all redshifts. CHILES (COSMOS H I Large Extragalactic Survey) 5 arcsec resolution is more than adequate to prevent confusion influencing stacking of its data, throughout its bandpass range. FAST (Five hundred metre Aperture Spherical Telescope) will be the most impeded by confusion, with H I surveys likely becoming heavily confused much beyond z = 0.1. The largest uncertainties in our model are the redshift evolution of the H I density of the Universe and the H I correlation function. However, we argue that the two idealized cases we adopt should bracket the true evolution, and the qualitative conclusions are unchanged regardless of the model choice. The profile shape of the signal due to confusion (in the absence of any detection) was also modelled, revealing that it can take the form of a double Gaussian with a narrow and wide component.

  5. The Type Ia supernovae rate with Subaru/XMM-Newton Deep Survey

    NASA Astrophysics Data System (ADS)

    Okumura, Jun E.; Ihara, Yutaka; Doi, Mamoru; Morokuma, Tomoki; Pain, Reynald; Totani, Tomonori; Barbary, Kyle; Takanashi, Naohiro; Yasuda, Naoki; Aldering, Greg; Dawson, Kyle; Goldhaber, Gerson; Hook, Isobel; Lidman, Chris; Perlmutter, Saul; Spadafora, Anthony; Suzuki, Nao; Wang, Lifan

    2014-04-01

    We present measurements of the rates of high-redshift Type Ia supernovae derived from the Subaru/XMM-Newton Deep Survey (SXDS). We carried out repeated deep imaging observations with Suprime-Cam on the Subaru Telescope, and detected 1040 variable objects over 0.918 deg2 in the Subaru/XMM-Newton Deep Field. From the imaging observations, light curves in the observed i ' band are constructed for all objects, and we fit the observed light curves with template light curves. Out of the 1040 variable objects detected by the SXDS, 39 objects over the redshift range 0.2 < z < 1.4 are classified as Type Ia supernovae using the light curves. These are among the most distant SN Ia rate measurements to date. We find that the Type Ia supernova rates increase up to z ˜ 0.8 and may then flatten at higher redshift. The rates can be fitted by a simple power law, rV(z) = r0(1 + z)α with r_0=0.20^{+0.52}_{-0.16}(stat.)^{+0.26}_{-0.07}(syst.) × 10-4 yr-1 Mpc-3, and α =2.04^{+1.84}_{-1.96}(stat.)^{+2.11}_{-0.86}(syst.).

  6. First hyperspectral survey of the deep seafloor: DISCOL area, Peru Basin

    NASA Astrophysics Data System (ADS)

    Dumke, Ines; Nornes, Stein M.; Ludvigsen, Martin

    2017-04-01

    Conventional hyperspectral seafloor surveys using airborne or satellite platforms are typically limited to shallow coastal areas. This limitation is due to the requirement for illumination by sunlight, which does not penetrate into deeper waters. For hyperspectral studies in deeper marine environments, such as the deep sea, a close-range, sunlight-independent survey approach is therefore required. Here, we present the first hyperspectral data from the deep seafloor. The data were acquired in 4200 m water depth in the DISCOL (disturbance-recolonization) area in the Peru Basin (SW Pacific). This area is characterized by seafloor manganese nodules and recolonization by benthic fauna after a seafloor disturbance experiment conducted in 1989, and was revisited in 2015 by the JPI Oceans cruise SO-242. The acquisition setup consisted of a new Underwater Hyperspectral Imager (UHI) mounted on a remotely operated vehicle (ROV), which provided illumination of the seafloor. High spatial and spectral resolution were achieved by an ROV altitude of 1 m and recording of 112 spectral bands between 380 nm and 800 nm (4 nm resolution). Spectral classification was performed to classify manganese nodules and benthic fauna and map their distribution in the study area. The results demonstrate the high potential of underwater hyperspectral imaging in mapping and classifying seafloor deposits and habitats.

  7. The Metal Abundances across Cosmic Time (MACT) Survey. I. Optical Spectroscopy in the Subaru Deep Field

    NASA Astrophysics Data System (ADS)

    Ly, Chun; Malhotra, Sangeeta; Malkan, Matthew A.; Rigby, Jane R.; Kashikawa, Nobunari; de los Reyes, Mithi A.; Rhoads, James E.

    2016-09-01

    Deep rest-frame optical spectroscopy is critical for characterizing and understanding the physical conditions and properties of the ionized gas in galaxies. Here, we present a new spectroscopic survey called “Metal Abundances across Cosmic Time” or { M }{ A }{ C }{ T }, which will obtain rest-frame optical spectra for ˜3000 emission-line galaxies. This paper describes the optical spectroscopy that has been conducted with MMT/Hectospec and Keck/DEIMOS for ≈1900 z = 0.1-1 emission-line galaxies selected from our narrowband and intermediate-band imaging in the Subaru Deep Field. In addition, we present a sample of 164 galaxies for which we have measured the weak [O iii]λ4363 line (66 with at least 3σ detections and 98 with significant upper limits). This nebular emission line determines the gas-phase metallicity by measuring the electron temperature of the ionized gas. This paper presents the optical spectra, emission-line measurements, interstellar properties (e.g., metallicity, gas density), and stellar properties (e.g., star formation rates, stellar mass). Paper II of the { M }{ A }{ C }{ T } survey (Ly et al.) presents the first results on the stellar mass-gas metallicity relation at z ≲ 1 using the sample with [O iii]λ4363 measurements.

  8. Observations of Mg II Absorption near z ~ 1 Galaxies Selected from the DEEP2 Redshift Survey

    NASA Astrophysics Data System (ADS)

    Lovegrove, Elizabeth; Simcoe, Robert A.

    2011-10-01

    We study the frequency of Mg II absorption in the outer halos of galaxies at z = 0.6-1.4 (with median z = 0.87), using new spectra obtained of 10 background quasars with galaxy impact parameters of b < 100 kpc. The quasar sight lines were selected from the Sloan Digital Sky Survey DR6 QSO catalog based on proximity to galaxies in the DEEP2 redshift survey. In addition to the 10 small impact systems, we examine 40 additional galaxies at 100 kpc < b < 500 kpc serendipitously located in the same fields. We detect Mg II absorbers with equivalent width Wr = 0.15-1.0 Å, though not all absorbers correlate with DEEP galaxies. We find five unique absorbers within Δv = 500 km s-1 and b < 100 kpc of a DEEP galaxy; this small sample contains both early- and late-type galaxies and has no obvious trends with star formation rate. No Mg II is detected more than 100 kpc from galaxies; inside this radius the covering fraction scales with impact parameter and galaxy luminosity in a very similar fashion to samples studied at lower redshift. In all but one case, when Mg II is detected without a spectroscopically confirmed galaxy, there exists a plausible photometric candidate which was excluded because of slit collision or apparent magnitude. We do not detect any strong absorbers with Wr > 1.0 Å, consistent with other samples of galaxy-selected Mg II systems. We speculate that Mg II systems with 0.3 < Wr < 1.0 trace old relic material from galactic outflows and/or the halo assembly process, and that in contrast, systems with large Wr are more likely to reflect the more recent star-forming history of their associated galaxies. This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile.

  9. The VIMOS VLT Deep Survey: the faint type-1 AGN sample

    NASA Astrophysics Data System (ADS)

    Gavignaud, I.; Bongiorno, A.; Paltani, S.; Mathez, G.; Zamorani, G.; Møller, P.; Picat, J. P.; Le Brun, V.; Marano, B.; Le Fèvre, O.; Bottini, D.; Garilli, B.; Maccagni, D.; Scaramella, R.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnaboldi, M.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Guzzo, L.; Ilbert, O.; Iovino, A.; McCracken, H. J.; Marinoni, C.; Mazure, A.; Meneux, B.; Merighi, R.; Pellò, R.; Pollo, A.; Pozzetti, L.; Radovich, M.; Zucca, E.; Bondi, M.; Busarello, G.; Cucciati, O.; de la Torre, S.; Gregorini, L.; Lamareille, F.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.; Vergani, D.

    2006-10-01

    We present the type-1 active galactic nuclei (AGN) sample extracted from the VIMOS VLT Deep Survey's first observations of 21 000 spectra in 1.75 deg^2. This sample, which is purely magnitude-limited and free of morphological or color-selection biases, contains 130 broad-line AGN (BLAGN) spectra with redshift up to 5. Our data are divided into a wide (I_AB ≤ 22.5) and a deep (I_AB ≤ 24) subsample containing 56 and 74 objects, respectively. Because of its depth and selection criteria, this sample is uniquely suited for studying the population of faint type-1 AGN. Our measured surface density (~472 ± 48 BLAGN per square degree with I_AB ≤ 24) is significantly higher than that of any other optically selected sample of BLAGN with spectroscopic confirmation. By applying a morphological and color analysis to our AGN sample, we find that (1) ~23 % of the AGN brighter than I_AB=22.5 are classified as extended, and this percentage increases to ~42% for those with z < 1.6; (2) a non-negligible fraction of our BLAGN are lying close to the color-space area occupied by stars in the u^*-g' versus g'-r' color-color diagram. This leads us to the conclusion that the classical optical-ultraviolet preselection technique, if employed at such deep magnitudes (I_AB=22.5) in conjuction with a preselection of point-like sources, can miss up to ~35% of the AGN population. Finally, we present a composite spectrum of our sample of objects. While the continuum shape is very similar to that of the SDSS composite at short wavelengths, it is much redder than that of the SDSS composite at λ ≥ 3000 Å. We interpret this as due to significant contamination from emission of the host galaxies, as expected from the faint absolute magnitudes sampled by our survey.

  10. TCS-CAIN: a deep multi-colour NIR survey of the Galactic plane

    NASA Astrophysics Data System (ADS)

    Cabrera-Lavers, A.; Garzón, F.; Hammersley, P. L.; Vicente, B.; González-Fernández, C.

    2006-07-01

    We describe a deep multi-colour NIR survey (TCS-CAIN) that has been recently completed at the Instituto de Astrofísica de Canarias (Spain). The survey is of selected areas distributed along the Galactic plane and it goes deeper than 2MASS or DENIS. Its aim was to explore the large-scale structure of the Milky Way and the Galactic components, in particular the Galactic bar. This survey has ~10 million point-source detections in J, H, and Ks filters with a photometric accuracy of ~0.1 mag in the three bands and a positional accuracy of ~0.2´´ (based on the 2MASS catalogue as the astrometric reference). Approximately 530 fields have been observed in near plane regions of the Galaxy covering a total area of ~41 deg2 in the sky. This survey is at least one magnitude deeper than 2MASS, and even more in the inner Galaxy where it is less limited by source confusion.

  11. The International Deep Planet Survey. II. The frequency of directly imaged giant exoplanets with stellar mass

    NASA Astrophysics Data System (ADS)

    Galicher, R.; Marois, C.; Macintosh, B.; Zuckerman, B.; Barman, T.; Konopacky, Q.; Song, I.; Patience, J.; Lafrenière, D.; Doyon, R.; Nielsen, E. L.

    2016-10-01

    Context. Radial velocity and transit methods are effective for the study of short orbital period exoplanets but they hardly probe objects at large separations for which direct imaging can be used. Aims: We carried out the international deep planet survey of 292 young nearby stars to search for giant exoplanets and determine their frequency. Methods: We developed a pipeline for a uniform processing of all the data that we have recorded with NIRC2/Keck II, NIRI/Gemini North, NICI/Gemini South, and NACO/VLT for 14 yr. The pipeline first applies cosmetic corrections and then reduces the speckle intensity to enhance the contrast in the images. Results: The main result of the international deep planet survey is the discovery of the HR 8799 exoplanets. We also detected 59 visual multiple systems including 16 new binary stars and 2 new triple stellar systems, as well as 2279 point-like sources. We used Monte Carlo simulations and the Bayesian theorem to determine that 1.05+2.80-0.70% of stars harbor at least one giant planet between 0.5 and 14 MJ and between 20 and 300 AU. This result is obtained assuming uniform distributions of planet masses and semi-major axes. If we consider power law distributions as measured for close-in planets instead, the derived frequency is 2.30+5.95-1.55%, recalling the strong impact of assumptions on Monte Carlo output distributions. We also find no evidence that the derived frequency depends on the mass of the hosting star, whereas it does for close-in planets. Conclusions: The international deep planet survey provides a database of confirmed background sources that may be useful for other exoplanet direct imaging surveys. It also puts new constraints on the number of stars with at least one giant planet reducing by a factor of two the frequencies derived by almost all previous works. Tables 11-15 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc

  12. The Vimos VLT deep survey. Global properties of 20,000 galaxies in the IAB < 22.5 WIDE survey

    NASA Astrophysics Data System (ADS)

    Garilli, B.; Le Fèvre, O.; Guzzo, L.; Maccagni, D.; Le Brun, V.; de la Torre, S.; Meneux, B.; Tresse, L.; Franzetti, P.; Zamorani, G.; Zanichelli, A.; Gregorini, L.; Vergani, D.; Bottini, D.; Scaramella, R.; Scodeggio, M.; Vettolani, G.; Adami, C.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Gavignaud, I.; Ilbert, O.; Iovino, A.; Lamareille, F.; McCracken, H. J.; Marano, B.; Marinoni, C.; Mazure, A.; Merighi, R.; Paltani, S.; Pellò, R.; Pollo, A.; Pozzetti, L.; Radovich, M.; Zucca, E.; Blaizot, J.; Bongiorno, A.; Cucciati, O.; Mellier, Y.; Moreau, C.; Paioro, L.

    2008-08-01

    .1 deg2 for a sample limited in magnitude to IAB = 22.5. Comparing galaxy densities from the four fields shows that in a redshift bin Δz = 0.1 at z ~ 1 one still has factor-of-two variations over areas as large as ~ 0.25 deg2. This level of cosmic variance agrees with that obtained by integrating the galaxy two-point correlation function estimated from the F22 field alone. It is also in fairly good statistical agreement with that predicted by the Millennium simulations. The VVDS WIDE survey currently provides the largest area coverage among redshift surveys reaching z ~ 1. The variance estimated over the survey fields shows explicitly how clustering results from deep surveys of even 1 deg2 size should be interpreted with caution. The survey data represent a rich data base to select complete sub-samples of high-quality spectra and to study galaxy ensemble properties and galaxy clustering over unprecedented scales at these redshifts. The redshift catalog of the 4 deg2 F22 field is publicly available at http://cencosw.oamp.fr.

  13. Morphology of Florida escarpment chemosynthetic brine seep community sites: deep-tow, seabeam, and GLORIA surveys

    SciTech Connect

    Paull, C.K.; Spiess, F.N.; Curray, J.R.; Twitchell, D.

    1988-02-01

    The Florida Escarpment near 26/degree/N was surveyed with Deep-Tow, Seabeam, and GLORIA in the area where chemosynthetic communities were discovered via ALVIN in the abyssal Gulf of Mexico. Seabeam bathymetry and GLORIA images indicate that the escarpment is a generally straight cliff with average slopes of about 45/degree/ from 2200 to more than 3250 m. The escarpment's face is cut by 2-km wide box canyons whose head walls are as steep as the intervening escarpment's face. The shapes of these canyons are difficult to explain with the traditional models of canyon formation. Sidescan sonar images and bottom photographs reveal that the escarpment's face is composed of a series of long, straight bedding-plain terraces which are truncated along nearly vertical orthogonal joints. Exposure of these truncated strata indicate the face of the escarpment is eroded. The contact between the basal escarpment and the flat-lying abyssal hemipelagic sediments is abrupt. Basal talus is uncommon because the abyssal floor is part of the distal Mississippi fan which is rapidly burying the escarpment. However, where talus occurs, it is in tongues of angular megabreccia of meter- and larger-sized blocks which indicate periodic catastrophic collapse. Sidescan images reveal bands of contrast in the reflective texture of the sea floor that extends 10-20 m from the base along more than 10% of the surveyed area. Photographic surveys show that these areas are associated with communities of abundant organisms. Apparently chemosynthetic communities line extensive sections of the escarpment base where reduced brines seep out into the sea floor. The morphology suggests joints and deep seeps are controlling factors in scarp retreat.

  14. Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey -- UDS Field

    NASA Astrophysics Data System (ADS)

    Faber, Sandra

    2010-09-01

    The Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey {CANDELS}is designed to document the ?rst third of galactic evolution from z =8 to 1.5 via deep imaging of more than 250,000 galaxies with WFC3/IRand ACS. It will also find the first Type Ia SNe beyond z > 1.5 andestablish their accuracy as standard candles for cosmology. Fivepremier multi-wavelength sky regions are selected from the SpitzerExtragalactic Deep Survey {SEDS} to provide complementary IRAC imagingdata down to 26.5 AB mag, a unique resource for stellar masses at allredshifts. The use of ?ve widely separated ?elds mitigates cosmicvariance and yields statistically robust and complete samples ofgalaxies down to 10^9 solar masses out to z 8.The program merges two originally separate MCT proposals. The Faberprogram incorporates a ?Wide? imaging survey in three separate fieldsto 2 orbit depth over 0.2 sq. degrees, plus a ?Deep? imaging surveyto 12 orbit depth in the two GOODS regions over 0.04 sq. degrees.In combination with ultra-deep imaging from the Hubble Ultradeep Fieldprogram {GO 11563}, the result is a three-tiered strategy that ef?cientlysamples both bright/rare and faint/common extragalactic objects. TheFerguson program adds an extensive high-redshift Type Ia SNe search,plus ultraviolet "daytime" UVIS exposures in GOODS-N to exploit theCVZ opportunity in that field.This program, GO 12064, is part of the Wide mosaic survey, which has thefollowing field centers and sizes: Field ID RA{2000} Dec{2000} WFC3 Dim. PA on sky UDS 02 17 38 -05 12 02 4x11 270 COSMOS 10 00 31 +02 24 00 4x11 180 EGS 14 19 31 +52 54 10 3x15 41 Science highlights from the Wide program: * Underlying structural properties of galaxies as revealed by WFC3-IR images sensitive to older stars {beyond the 4000-A break} and less affected by dust than ACS. A key redshift is z 2, where star-formation peaks, QSOs are most abundant, and where restframe B-band is still accessible to WFC3. Sample questions include: - Structure in young

  15. Deep VLT/HAWKI and Keck/MOSFIRE K-band imaging of the Hubble Frontier Fields

    NASA Astrophysics Data System (ADS)

    Brammer, Gabriel; Marchesini, Danilo

    2015-08-01

    We will present recently-obtained deep K-band imaging of the first four Frontier Fields, Abell 2744 and MACS 0416 with the VLT/HAWK-I instrument and MACS-0717 and MACS-1149 with Keck/MOSFIRE. The final HAWK-I mosaics reach a depth of K~26 AB (5-sigma) with superb ground-based image quality ~0.4" FWHM across the field; shorter integrations with MOSFIRE reach K~25 AB and with FWHM~0.5". The 7'x7' HAWKI field of view provides ideal simultaneous coverage of both the HST cluster and parallel fields (with additional area also covered by Subaru optical and IRAC imaging), and the K band at 2.2 µm crucially fills the gap between the deep space-based imaging bandpasses observed with HST and Spitzer. The addition of the 2.2 µm imaging and photometry greatly improves the constraints on both the photometric redshifts and the stellar-population properties of galaxies extending well below the characteristic stellar mass across most of the age of the universe, down to, and including, the redshifts of the targeted galaxy clusters. The reduced, aligned mosaics of all the K-band fields are made freely available to the Frontier Fields community; identical deep HAWK-I observations of the final two Frontier Fields (Abell 370 and Abell S1063) have been awarded and will be obtained in the upcoming ESO observing periods.

  16. Search for cosmic strings in the Great Observatories Origins Deep Survey

    SciTech Connect

    Christiansen, J. L.; Albin, E.; James, K. A.; Goldman, J.; Maruyama, D.; Smoot, G. F.

    2008-06-15

    We search Hubble Space Telescope Treasury Program images collected as part of the Great Observatories Origins Deep Survey for pairs of galaxies consistent with the gravitational lensing signature of a cosmic string. Our technique includes estimates of the efficiency for finding the lensed galaxy pair. In the north (south) survey field we find no evidence out to a redshift of greater than 0.5 (0.3) for cosmic strings to a mass per unit length limit of G{mu}/c{sup 2}<3.0x10{sup -7} at 95% confidence limits (C.L.). In the combined 314.9 arcmin{sup 2} of the north and south survey fields this corresponds to a global limit on {omega}{sub strings}<0.02. Our limit on G{mu}/c{sup 2} is more than an order of magnitude lower than searches for individual strings in cosmic microwave background (CMB) data. Our limit is higher than other CMB and gravitational wave searches, however, we note that it is less model dependent than these other searches.

  17. A very deep IRAS survey at l(II) = 97 deg, b(II) = +30 deg

    NASA Astrophysics Data System (ADS)

    Hacking, Perry; Houck, James R.

    1987-05-01

    A deep far-infrared survey is presented using over 1000 scans made of a 4 to 6 sq. deg. field at the north ecliptic pole by the IRAS. Point sources from this survey are up to 100 times fainter than the IRAS point source catalog at 12 and 25 micrometers, and up to 10 times fainter at 60 and 100 micrometers. The 12 and 25 micrometer maps are instrumental noise-limited, and the 60 and 100 micrometer maps are confusion noise-limited. The majority of the 12 micrometer point sources are stars within the Milky Way. The 25 micrometer sources are composed almost equally of stars and galaxies. About 80% of the 60 micrometer sources correspond to galaxies on Palomar Observatory Sky Survey (POSS) enlargements. The remaining 20% are probably galaxies below the POSS detection limit. The differential source counts are presented and compared with what is predicted by the Bahcall and Soneira Standard Galaxy Model using the B-V-12 micrometer colors of stars without circumstellar dust shells given by Waters, Cote and Aumann. The 60 micrometer source counts are inconsistent with those predicted for a uniformly distributed, nonevolving universe. The implications are briefly discussed.

  18. Orbital Inclinations of Kuiper Belt Objects: Results from the Deep Ecliptic Survey

    NASA Astrophysics Data System (ADS)

    Elliot, J. L.; Kern, S. D.; Millis, R. L.; Buie, M. W.; Wasserman, L. H.; Wagner, R. M.

    2000-10-01

    One reason to expect a trans-Neptunian disk population as the source of the short period comets is that the orbits of the short period comets have small inclinations compared with the distribution of orbital inclinations that would be expected from an Oort-cloud source (Duncan, Quinn & Tremaine, 1988, ApJL 328, L69). Hence one of the objectives of our deep ecliptic survey with the Mosaic cameras at KPNO and CTIO (Millis et al., this conference) is the determination of the inclination distribution for Kuiper Belt Objects, in order to compare it with that of the short period comets. Although most of our survey has occurred within a few degrees of the ecliptic, orbits of all inclinations pass through this region. We have confirmed discoveries of KBOs with a variety of inclinations (the greatest being 31 degrees), and confirmed discoveries of KBOs by others with inclinations as high as 40 degrees have been reported to the Minor Planet Center. A body in an orbit of high inclination, of course, spends a small fraction of its period near the ecliptic, but this observational bias can be removed. We shall present the unbiased orbital-inclination distribution for the KBOs discovered by our survey. This work has been supported, in part, by NASA Grants NAG5-8990 to Lowell Observatory, and NAG5-3940 to MIT.

  19. A 6 GHz Synoptic Survey of the COSMOS Deep Field with the JVLA

    NASA Astrophysics Data System (ADS)

    Sink, Joseph R.; Myers, Steven T.

    2016-01-01

    The Cosmic Evolution Survey (COSMOS) covers two square degrees, and is observed over a large portion of the electromagnetic spectrum from X-ray to Radio. Key science goals of COSMOS include probing the evolution of galaxies, AGN, and large scale structures of the Universe. As well as constraining cosmological models and the star and structure formation history of the Universe. The wide range of frequencies and deep surveys are suitable for many astrophysical studies.Beginning in 2013, observations of the COSMOS field in C-band (4 - 8 GHz) using the JVLA have been carried out in every configuration spanning 21 months (April 2013 - Jan 2015) for a total of 13 observations. The observations are comprised of 1 hour time blocks using a technique called On-The-Fly Mosaicking (OTFM). Using OTFM we see an increased efficiency for an allotted observation block by collecting data as the array scans across the field, rather than a pointed mosaic which requires settle down time after each new pointing. Each observation consists of 2160 1-second integrations on 432 phase centers that require calibration and image processing before they can be mosaicked to create the final image of the entire COSMOS field.The primary science goal of this survey is to identify, catalog, and study the variable and transient radio sources in the COSMOS field, comparing these to other radio, optical, IR, and X-ray observations. The main class of variables we are interested in Active Galactic Nuclei.

  20. A very deep IRAS survey at l(II) = 97 deg, b(II) = +30 deg

    NASA Technical Reports Server (NTRS)

    Hacking, Perry; Houck, James R.

    1987-01-01

    A deep far-infrared survey is presented using over 1000 scans made of a 4 to 6 sq. deg. field at the north ecliptic pole by the IRAS. Point sources from this survey are up to 100 times fainter than the IRAS point source catalog at 12 and 25 micrometers, and up to 10 times fainter at 60 and 100 micrometers. The 12 and 25 micrometer maps are instrumental noise-limited, and the 60 and 100 micrometer maps are confusion noise-limited. The majority of the 12 micrometer point sources are stars within the Milky Way. The 25 micrometer sources are composed almost equally of stars and galaxies. About 80% of the 60 micrometer sources correspond to galaxies on Palomar Observatory Sky Survey (POSS) enlargements. The remaining 20% are probably galaxies below the POSS detection limit. The differential source counts are presented and compared with what is predicted by the Bahcall and Soneira Standard Galaxy Model using the B-V-12 micrometer colors of stars without circumstellar dust shells given by Waters, Cote and Aumann. The 60 micrometer source counts are inconsistent with those predicted for a uniformly distributed, nonevolving universe. The implications are briefly discussed.

  1. The VIMOS VLT deep survey. Computing the two point correlation statistics and associated uncertainties

    NASA Astrophysics Data System (ADS)

    Pollo, A.; Meneux, B.; Guzzo, L.; Le Fèvre, O.; Blaizot, J.; Cappi, A.; Iovino, A.; Marinoni, C.; McCracken, H. J.; Bottini, D.; Garilli, B.; Le Brun, V.; Maccagni, D.; Picat, J. P.; Scaramella, R.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnaboldi, M.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Ilbert, O.; Marano, B.; Mathez, G.; Mazure, A.; Merighi, R.; Paltani, S.; Pellò, R.; Pozzetti, L.; Radovich, M.; Zamorani, G.; Zucca, E.; Bondi, M.; Bongiorno, A.; Busarello, G.; Gregorini, L.; Lamareille, F.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2005-09-01

    We present a detailed description of the methods used to compute the three-dimensional two-point galaxy correlation function in the VIMOS-VLT deep survey (VVDS). We investigate how instrumental selection effects and observational biases affect the measurements and identify the methods to correct for them. We quantify the accuracy of our corrections using an ensemble of 50 mock galaxy surveys generated with the GalICS semi-analytic model of galaxy formation which incorporate the selection biases and tiling strategy of the real data. We demonstrate that we are able to recover the real-space two-point correlation function ξ(s) and the projected correlation function w_p(r_p) to an accuracy better than 10% on scales larger than 1 h-1 Mpc with the sampling strategy used for the first epoch VVDS data. The large number of simulated surveys allows us to provide a reliable estimate of the cosmic variance on the measurements of the correlation length r0 at z ˜ 1, of about 15-20% for the first epoch VVDS observation while any residual systematic effect in the measurements of r0 is always below 5%. The error estimation and measurement techniques outlined in this paper are being used in several parallel studies which investigate in detail the clustering properties of galaxies in the VVDS.

  2. The Vimos-VLT Deep Survey: Results from the First-Epoch Observations

    NASA Astrophysics Data System (ADS)

    Paltani, S.; Ilbert, O.; Le Fèvre, O.; Marinoni, C.; Bottini, D.; Garilli, B.; Le Brun, V.; Maccagni, D.; Picat, J.-P.; Scaramella, R.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnaboldi, M.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Cappi, A.; Charlot, S.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Iovino, A.; McCracken, H. J.; Marano, B.; Mazure, A.; Meneux, B.; Merighi, R.; Pellò, R.; Pollo, A.; Pozzetti, L.; Radovich, M.; Zamorani, G.; Zucca, E.; Bondi, M.; Bongiorno, A.; Busarello, G.; Ciliegi, P.; Gregorini, L.; Mathez, G.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2005-06-01

    The Vimos-VLT Deep Survey is a spectroscopic survey aiming at collecting more than 50000 spectra down to a limiting magnitude IAB=24, and 100000 down to IAB=22.5, on a total of about 16 deg2 without any color or morphology preselection. We present the N(z) distribution up to z˜ 5, obtained from a purely magnitude-limited sample down to IAB=24, which is an important input to weak-lensing studies. We discuss the evolution of the galaxy luminosity function up to z˜ 2, which exhibits a very strong increase in the typical galaxy luminosity Δ M*≃ -2.5 in the U band compared to the local value. Surveys like the VVDS also allow to study the galaxy bias as a function of redshift without assumption about its linearity, an assumption that we find to be violated in some cases. A low bias is found, and the linear bias is shown to increase with redshift.

  3. A Deep X-Ray Survey of Low Mass PMS Stars in NGC 2264

    NASA Technical Reports Server (NTRS)

    Patten, Brian M.; Mushotzky, Richard (Technical Monitor)

    2001-01-01

    We have proposed to make a deep X-ray survey of a rotation- and proper-motion selected sample of young (3-15 Myr old), low-mass, pre-main sequence (PMS) stars in the populous star-forming region NGC 2264. These X-ray Multimirror Mission (XMM) data will be combined with an extensive set of rotation data for members of this cluster to allow us, for the first time, to probe the early evolution of magnetic dynamo activity for both fully convective stars and those stars found lower on their Hayashi tracks, which are developing radiative cores. We will use these data to study the interrelationship between rotation, interior structure, and coronal activity as a function of mass and age in the PMS and to define empirical constraints for theoretical models of angular momentum/dynamo evolution.

  4. The VIRMOS-VLT Deep Survey: the Last 10 Billion Years of Evolution of Galaxy Clustering

    NASA Astrophysics Data System (ADS)

    Pollo, A.; Guzzo, L.; Le Fèvre, O.; Meneux, B.; Cappi, A.; McCracken, H. J.; Iovino, A.; Marinoni, C.; Bottini, D.; Garilli, B.; Le Brun, V. L.; Maccagni, D.; Picat, J. P.; Scaramella, R.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Ilbert, O.; Marano, B.; Mazure, A.; Merighi, R.; Paltani, S.; Pellò, R.; Pozzetti, L.; Radovich, M.; Zamorani, G.; Zucca, E.; Bondi, M.; Bongiorno, A.; Brinchmann, J.; Cucciati, O.; de la Torre, S.; Lamareille, F.; Mellier, Y.; Merluzzi, P.; Temporin, S.; Vergani, D.; Walcher, C. J.

    2007-12-01

    We discuss the evolution of clustering of galaxies in the Universe from the present epoch back to z ˜ 2, using the first-epoch data from the VIMOS-VLT Deep Survey (VVDS). We present the evolution of the projected two-point correlation function of galaxies for the global galaxy population, as well as its dependence on galaxy intrinsic luminosities and spectral types. While we do not find strong variations of the correlation function parameters with redshift for the global galaxy population, the clustering of objects with different intrinsic luminosities evolved significantly during last 8-10 billion years. Our findings indicate that bright galaxies in the past traced higher density peaks than they do now and that the shape of the correlation function of most luminous galaxies is different from observed for their local counterparts, which is a supporting evidence of a non-trivial evolution of the galaxy vs. dark matter bias.

  5. A Deep HRI Survey of Low-Mass PMS Stars in NGC 2264

    NASA Technical Reports Server (NTRS)

    Patten, Brian

    1999-01-01

    Brian Patten is the Principal Investigator of the NASA ADP project 'A Deep HRI Survey of Low-Mass PMS Stars in NGC 2264'. This project was funded to support primarily the data reduction and analysis for new ROSAT data to be acquired in ROSAT AO8. For AO8 we were awarded two deep (100 ks) exposures with the ROSAT HRI instrument of a rotation and proper-motion selected sample of young (3 Myr - 15 Myr), low-mass, PMS stars in the populous star-forming region NGC 2264. These X-ray data were to be combined with an extensive rotation database for members of this cluster to allow us, for the first time, to probe the early evolution of magnetic dynamo activity for both fully convective stars and those stars found lower on the Hayashi tracks which have developed radiative cores. This database would have been used to study the interrelationship between coronal activity level, interior structure, and rotation rate as a function of mass and age.in the PMS and to define empirical constraints for theoretical models of angular momentum and magnetic dynamo evolution.

  6. Identifying Variations to the IMF at High-z Through Deep Radio Surveys

    NASA Astrophysics Data System (ADS)

    Murphy, E. J.

    2011-06-01

    In this article I briefly describe how deep radio surveys may provide a means to identify variations in the upper end of the initial mass function (IMF) in star-forming galaxies at high redshifts (i.e., z ≳ 3). At such high redshifts, I argue that deep radio continuum observations at frequencies ≳10 GHz using next generation facilities (e.g., EVLA, MeerKAT, SKA/NAA) will likely provide the most accurate measurements for the ionizing photon rates (star formation rates; SFRs) of normal galaxies since their non-thermal emission should be highly suppressed due to the increased inverse Compton (IC) losses from the cosmic microwave background (CMB), leaving only thermal (free-free) emission detectable. Thus, a careful analysis of such observations in combination with future ALMA and JWST data, measuring the rest-frame far-infrared and UV emission from the same population of galaxies, may yield the best means to search for variability in the stellar IMF at such epochs.

  7. Near-bottom Multibeam Survey Capabilities in the US National Deep Submergence Facility (Invited)

    NASA Astrophysics Data System (ADS)

    Yoerger, D. R.; McCue, S. J.; Jason; Sentry Operations Groups

    2010-12-01

    The US National Deep Submergence Facility (NDSF) provides near-bottom multibeam mapping capabilities from the autonomous underwater vehicle Sentry and the remotely operated vehicle Jason. These vehicles can be used to depths of 4500 and 6500m respectively. Both vehicles are equipped with Reson 7125 400khz multibeam sonars as well as compatible navigation equipment (inertial navigation systems, doppler velocity logs, and acoustic navigation systems). These vehicles have produced maps of rugged Mid-Ocean Ridge terrain in the Galapagos Rift, natural oil and gas seeps off the coast of Southern California, deep coral sites in the Gulf of Mexico, and sites for the Ocean Observing Initiative off the coast of Oregon. Multibeam surveys are conducted from heights between 20 and 80 meters, allowing the scientific user to select the tradeoff between resolution and coverage rate. In addition to conventional bathymetric mapping, the systems have used to image methane bubble plumes from natural seeps. This talk will provide summaries of these mapping efforts and describe the data processing pipeline used to produce maps shortly after each dive. Development efforts to reduce navigational errors and reconcile discrepancies between adjacent swaths will also be described.

  8. Selected First Results from the 7 Ms Chandra Deep Field-South Survey

    NASA Astrophysics Data System (ADS)

    Brandt, W. Niel; Chandra Deep Field-South Team

    2017-01-01

    The exposure on the Chandra Deep Field-South (CDF-S) has recently been increased to 7 Ms, making it the most sensitive extragalactic X-ray survey by a wide margin. About 1050 X-ray sources have been detected, primarily distant active galactic nuclei (AGNs) and starburst/normal galaxies. The unmatched deep multiwavelength coverage for these sources allows superb follow-up investigations; e.g., 98.4% of the X-ray sources have multiwavelength counterparts, and 97.8% have spectroscopic/photometric redshifts. I will briefly describe the source catalog for the 7 Ms CDF-S and some exciting first science results. The latter will likely include (1) constraints on SMBH growth in the first galaxies as revealed by direct detection and stacking; (2) long-term variability studies of the AGNs producing most of cosmic accretion power; (3) AGN/galaxy interactions as investigated via the host properties of X-ray AGNs; and (4) measurements of the evolving X-ray binary populations of normal and starburst galaxies.

  9. Deep sea three component magnetic survey using ROV in the hydrothermal vent of the Lau Basin

    NASA Astrophysics Data System (ADS)

    Kim, C.; Park, C.

    2011-12-01

    We conducted magnetic survey at Apr., 2011 in the western slope of the caldera of TA25, the Lau Basin, the southwestern Pacific using IBRV(Ice Breaker Research Vessel) ARAON of KORDI(Korea Ocean Research and Development Institute), ROV(Remotely Operated Vehicle) of Oceaneering Co. and three component magnetometer(Fig. 1,Fig. 2). The deep-sea three component magnetic survey lines are the 13 N-S lines(100 m spacing) and the 2 E-W lines(Fig. 2). The depth ranges of the survey area are from about 900 m to 1200 m, below sea level. For the magnetic survey, the magnetometer sensor and the data logger was attached with the upper part and lower part of ROV, respectively(Fig. 2). We wanted to make the distance between the magnetometer sensor and ROV over 2 m long to reduce the noise effect of ROV. But, for the safe of deployment and recovery of ROV, the distance between the magnetometer sensor and ROV was 126 cm(Fig. 2). In the magnetic survey, ROV followed the planning tracks at 25~30 m above seafloor using the altimeter and USBL(Ultra Short Base Line) of ROV. IBRV ARAON accompanied ROV on the magnetic survey. The three component magnetometer measure the X(North), Y(East) and Z(Vertical) vector components of a magnetic field. A motion sensor(Oxtans) provided us the data of pitch, roll, yaw for the correction of the magnetic data to the motion of ROV. The data of the magnetometer sensor and the motion sensor were recorded on a notebook through the optical cable of ROV and the network of ARON using magnetometer software. The precision positions of magnetic data were merged by the post-processing of USBL of ROV. Hydrothermal fluids over Curie temperature can quickly alter or replace the iron-rich magnetic minerals, reducing the magnetic remanence of the crustal rocks, in some cases to near 0A/m magnetization. So, the obtained three component magnetic data are fully utilized by finding possible hydrothermal vents of the survey area.

  10. The VIMOS Ultra Deep Survey: 10 000 Galaxies to Study the Early Phases of Galaxy Assembly at 2 < z < 6+

    NASA Astrophysics Data System (ADS)

    Le Fèvre, O.; Amorin, R.; Bardelli, S.; Capak, P.; Cassara, L.; Cassata, P.; Castellano, M.; Charlot, S.; Cimatti, A.; Contini, T.; Cuby, J.; Cucciati, O.; Durkalec, A.; de la Torre, S.; Fontana, A.; Fotopoulou, S.; Garilli, B.; Giavalisco, M.; Grazian, A.; Hathi, N.; Ilbert, O.; Le Brun, V.; Lemaux, B.; Lopez-Sanjuan, C.; Maccagni, D.; Mellier, Y.; Moreau, C.; Paltani, S.; Pentericci, L.; Ribeiro, B.; Salvato, M.; Schaerer, D.; Scodeggio, M.; Scoville, N.; Sommariva, V.; Talia, M.; Taniguchi, Y.; Tasca, L.; Thomas, R.; Tresse, L.; Vanzella, E.; Vergani, D.; Wang, P.; Zamorani, G.; Zucca, E.

    2014-03-01

    The VIMOS Ultra Deep Survey (VUDS) aims to study the early phases of galaxy assembly from a large, well-defined sample of ~ 10 000 galaxies with spectra obtained from very deep VIMOS observations. This sample is by far the largest to date, with spectroscopic redshifts covering a redshift range 2 survey are summarised, including the discovery of a galaxy proto-cluster at z = 3.3.

  11. MID-INFRARED VARIABILITY FROM THE SPITZER DEEP WIDE-FIELD SURVEY

    SciTech Connect

    Kozlowski, Szymon; Kochanek, Christopher S.; Assef, Roberto J.; Stern, Daniel; Eisenhardt, P. R.; Gorjian, V.; Griffith, R.; Ashby, Matthew L. N.; Brodwin, M.; Bock, J. J.; Borys, C.; Brand, K.; Grogin, N.; Brown, M. J. I.; Cool, R.; Cooray, A.; Croft, S.; Dey, Arjun; Gonzalez, A.; Ivison, R.

    2010-06-10

    We use the multi-epoch, mid-infrared Spitzer Deep Wide-Field Survey to investigate the variability of objects in 8.1 deg{sup 2} of the NOAO Deep Wide Field Survey Booetes field. We perform a Difference Image Analysis of the four available epochs between 2004 and 2008, focusing on the deeper 3.6 and 4.5 {mu}m bands. Out of 474, 179 analyzed sources, 1.1% meet our standard variability selection criteria that the two light curves are strongly correlated (r>0.8) and that their joint variance ({sigma}{sub 12}) exceeds that for all sources with the same magnitude by 2{sigma}. We then examine the mid-IR colors of the variable sources and match them with X-ray sources from the XBooetes survey, radio catalogs, 24 {mu}m selected active galactic nucleus (AGN) candidates, and spectroscopically identified AGNs from the AGN and Galaxy Evolution Survey (AGES). Based on their mid-IR colors, most of the variable sources are AGNs (76%), with smaller contributions from stars (11%), galaxies (6%), and unclassified objects, although most of the stellar, galaxy, and unclassified sources are false positives. For our standard selection criteria, 11%-12% of the mid-IR counterparts to X-ray sources, 24 {mu}m AGN candidates, and spectroscopically identified AGNs show variability. The exact fractions depend on both the search depth and the selection criteria. For example, 12% of the 1131 known z>1 AGNs in the field and 14%-17% of the known AGNs with well-measured fluxes in all four Infrared Array Camera bands meet our standard selection criteria. The mid-IR AGN variability can be well described by a single power-law structure function with an index of {gamma} {approx} 0.5 at both 3.6 and 4.5 {mu}m, and an amplitude of S {sub 0} {approx_equal} 0.1 mag on rest-frame timescales of 2 yr. The variability amplitude is higher for shorter rest-frame wavelengths and lower luminosities.

  12. Mid-infrared Variability from the Spitzer Deep Wide-field Survey

    NASA Astrophysics Data System (ADS)

    Kozłowski, Szymon; Kochanek, Christopher S.; Stern, Daniel; Ashby, Matthew L. N.; Assef, Roberto J.; Bock, J. J.; Borys, C.; Brand, K.; Brodwin, M.; Brown, M. J. I.; Cool, R.; Cooray, A.; Croft, S.; Dey, Arjun; Eisenhardt, P. R.; Gonzalez, A.; Gorjian, V.; Griffith, R.; Grogin, N.; Ivison, R.; Jacob, J.; Jannuzi, B. T.; Mainzer, A.; Moustakas, L.; Röttgering, H.; Seymour, N.; Smith, H. A.; Stanford, S. A.; Stauffer, J. R.; Sullivan, I. S.; van Breugel, W.; Willner, S. P.; Wright, E. L.

    2010-06-01

    We use the multi-epoch, mid-infrared Spitzer Deep Wide-Field Survey to investigate the variability of objects in 8.1 deg2 of the NOAO Deep Wide Field Survey Boötes field. We perform a Difference Image Analysis of the four available epochs between 2004 and 2008, focusing on the deeper 3.6 and 4.5 μm bands. Out of 474, 179 analyzed sources, 1.1% meet our standard variability selection criteria that the two light curves are strongly correlated (r>0.8) and that their joint variance (σ12) exceeds that for all sources with the same magnitude by 2σ. We then examine the mid-IR colors of the variable sources and match them with X-ray sources from the XBoötes survey, radio catalogs, 24 μm selected active galactic nucleus (AGN) candidates, and spectroscopically identified AGNs from the AGN and Galaxy Evolution Survey (AGES). Based on their mid-IR colors, most of the variable sources are AGNs (76%), with smaller contributions from stars (11%), galaxies (6%), and unclassified objects, although most of the stellar, galaxy, and unclassified sources are false positives. For our standard selection criteria, 11%-12% of the mid-IR counterparts to X-ray sources, 24 μm AGN candidates, and spectroscopically identified AGNs show variability. The exact fractions depend on both the search depth and the selection criteria. For example, 12% of the 1131 known z>1 AGNs in the field and 14%-17% of the known AGNs with well-measured fluxes in all four Infrared Array Camera bands meet our standard selection criteria. The mid-IR AGN variability can be well described by a single power-law structure function with an index of γ ≈ 0.5 at both 3.6 and 4.5 μm, and an amplitude of S 0 ~= 0.1 mag on rest-frame timescales of 2 yr. The variability amplitude is higher for shorter rest-frame wavelengths and lower luminosities.

  13. The Chandra Deep Survey of the Hubble Deep Field-North Area. II. Results from the Caltech Faint Field Galaxy Redshift Survey Area

    NASA Astrophysics Data System (ADS)

    Hornschemeier, A. E.; Brandt, W. N.; Garmire, G. P.; Schneider, D. P.; Barger, A. J.; Broos, P. S.; Cowie, L. L.; Townsley, L. K.; Bautz, M. W.; Burrows, D. N.; Chartas, G.; Feigelson, E. D.; Griffiths, R. E.; Lumb, D.; Nousek, J. A.; Ramsey, L. W.; Sargent, W. L. W.

    2001-06-01

    A deep X-ray survey of the Hubble Deep Field-North (HDF-N) and its environs is performed using data collected by the Advanced CCD Imaging Spectrometer (ACIS) on board the Chandra X-Ray Observatory. Currently a 221.9 ks exposure is available, the deepest ever presented, and here we give results on X-ray sources located in the 8.6‧×8.7‧ area covered by the Caltech Faint Field Galaxy Redshift Survey (the ``Caltech area''). This area has (1) deep photometric coverage in several optical and near-infrared bands; (2) extensive coverage at radio, submillimeter, and mid-infrared wavelengths; and (3) some of the deepest and most complete spectroscopic coverage ever obtained. It is also where the X-ray data have the greatest sensitivity; the minimum detectable fluxes in the 0.5-2 keV (soft) and 2-8 keV (hard) bands are ~1.3×10-16 and ~6.5×10-16 ergs cm-2 s-1, respectively. More than ~80% of the extragalactic X-ray background in the hard band is resolved. The 82 Chandra sources detected in the Caltech area are correlated with more than 25 multiwavelength source catalogs, and the results of these correlations as well as spectroscopic follow-up results obtained with the Keck and Hobby-Eberly Telescopes are presented. All but nine of the Chandra sources are detected optically with R<~26.5. Redshifts are available for 39% of the Chandra sources, including 96% of the sources with R<23 the redshift range is 0.1-3.5, with most sources having z<1.5. Eight of the X-ray sources are located in the HDF-N itself, including two not previously reported. A population of X-ray faint, optically bright, nearby galaxies emerges at soft-band fluxes of <~3×10-16 ergs cm-2 s-1. Our multiwavelength correlations have set the tightest constraints to date on the X-ray emission properties of μJy radio sources, mid-infrared sources detected by the Infrared Space Observatory (ISO), and very red (R-Ks>5.0) objects. A total of 16 of the 67 1.4 GHz μJy sources in the Caltech area are detected in the

  14. Cosmic shear results from the deep lens survey. II. Full cosmological parameter constraints from tomography

    SciTech Connect

    Jee, M. James; Tyson, J. Anthony; Hilbert, Stefan; Schneider, Michael D.; Schmidt, Samuel; Wittman, David

    2016-06-15

    Here, we present a tomographic cosmic shear study from the Deep Lens Survey (DLS), which, providing a limiting magnitude ${r}_{\\mathrm{lim}}\\sim 27$ ($5\\sigma $), is designed as a precursor Large Synoptic Survey Telescope (LSST) survey with an emphasis on depth. Using five tomographic redshift bins, we study their auto- and cross-correlations to constrain cosmological parameters. We use a luminosity-dependent nonlinear model to account for the astrophysical systematics originating from intrinsic alignments of galaxy shapes. We find that the cosmological leverage of the DLS is among the highest among existing $\\gt 10$ deg2 cosmic shear surveys. Combining the DLS tomography with the 9 yr results of the Wilkinson Microwave Anisotropy Probe (WMAP9) gives ${{\\rm{\\Omega }}}_{m}={0.293}_{-0.014}^{+0.012}$, ${\\sigma }_{8}={0.833}_{-0.018}^{+0.011}$, ${H}_{0}={68.6}_{-1.2}^{+1.4}\\;{\\text{km s}}^{-1}\\;{{\\rm{Mpc}}}^{-1}$, and ${{\\rm{\\Omega }}}_{b}=0.0475\\pm 0.0012$ for ΛCDM, reducing the uncertainties of the WMAP9-only constraints by ~50%. When we do not assume flatness for ΛCDM, we obtain the curvature constraint ${{\\rm{\\Omega }}}_{k}=-{0.010}_{-0.015}^{+0.013}$ from the DLS+WMAP9 combination, which, however, is not well constrained when WMAP9 is used alone. The dark energy equation-of-state parameter w is tightly constrained when baryonic acoustic oscillation (BAO) data are added, yielding $w=-{1.02}_{-0.09}^{+0.10}$ with the DLS+WMAP9+BAO joint probe. The addition of supernova constraints further tightens the parameter to $w=-1.03\\pm 0.03$. Our joint constraints are fully consistent with the final Planck results and also with the predictions of a ΛCDM universe.

  15. Cosmic shear results from the deep lens survey. II. Full cosmological parameter constraints from tomography

    SciTech Connect

    Jee, M. James; Tyson, J. Anthony; Hilbert, Stefan; Schneider, Michael D.; Schmidt, Samuel; Wittman, David

    2016-06-15

    Here, we present a tomographic cosmic shear study from the Deep Lens Survey (DLS), which, providing a limiting magnitude ${r}_{\\mathrm{lim}}\\sim 27$ ($5\\sigma $), is designed as a precursor Large Synoptic Survey Telescope (LSST) survey with an emphasis on depth. Using five tomographic redshift bins, we study their auto- and cross-correlations to constrain cosmological parameters. We use a luminosity-dependent nonlinear model to account for the astrophysical systematics originating from intrinsic alignments of galaxy shapes. We find that the cosmological leverage of the DLS is among the highest among existing $\\gt 10$ deg2 cosmic shear surveys. Combining the DLS tomography with the 9 yr results of the Wilkinson Microwave Anisotropy Probe (WMAP9) gives ${{\\rm{\\Omega }}}_{m}={0.293}_{-0.014}^{+0.012}$, ${\\sigma }_{8}={0.833}_{-0.018}^{+0.011}$, ${H}_{0}={68.6}_{-1.2}^{+1.4}\\;{\\text{km s}}^{-1}\\;{{\\rm{Mpc}}}^{-1}$, and ${{\\rm{\\Omega }}}_{b}=0.0475\\pm 0.0012$ for ΛCDM, reducing the uncertainties of the WMAP9-only constraints by ~50%. When we do not assume flatness for ΛCDM, we obtain the curvature constraint ${{\\rm{\\Omega }}}_{k}=-{0.010}_{-0.015}^{+0.013}$ from the DLS+WMAP9 combination, which, however, is not well constrained when WMAP9 is used alone. The dark energy equation-of-state parameter w is tightly constrained when baryonic acoustic oscillation (BAO) data are added, yielding $w=-{1.02}_{-0.09}^{+0.10}$ with the DLS+WMAP9+BAO joint probe. The addition of supernova constraints further tightens the parameter to $w=-1.03\\pm 0.03$. Our joint constraints are fully consistent with the final Planck results and also with the predictions of a ΛCDM universe.

  16. Cosmic shear results from the deep lens survey. II. Full cosmological parameter constraints from tomography

    DOE PAGES

    Jee, M. James; Tyson, J. Anthony; Hilbert, Stefan; ...

    2016-06-15

    Here, we present a tomographic cosmic shear study from the Deep Lens Survey (DLS), which, providing a limiting magnitudemore » $${r}_{\\mathrm{lim}}\\sim 27$$ ($$5\\sigma $$), is designed as a precursor Large Synoptic Survey Telescope (LSST) survey with an emphasis on depth. Using five tomographic redshift bins, we study their auto- and cross-correlations to constrain cosmological parameters. We use a luminosity-dependent nonlinear model to account for the astrophysical systematics originating from intrinsic alignments of galaxy shapes. We find that the cosmological leverage of the DLS is among the highest among existing $$\\gt 10$$ deg2 cosmic shear surveys. Combining the DLS tomography with the 9 yr results of the Wilkinson Microwave Anisotropy Probe (WMAP9) gives $${{\\rm{\\Omega }}}_{m}={0.293}_{-0.014}^{+0.012}$$, $${\\sigma }_{8}={0.833}_{-0.018}^{+0.011}$$, $${H}_{0}={68.6}_{-1.2}^{+1.4}\\;{\\text{km s}}^{-1}\\;{{\\rm{Mpc}}}^{-1}$$, and $${{\\rm{\\Omega }}}_{b}=0.0475\\pm 0.0012$$ for ΛCDM, reducing the uncertainties of the WMAP9-only constraints by ~50%. When we do not assume flatness for ΛCDM, we obtain the curvature constraint $${{\\rm{\\Omega }}}_{k}=-{0.010}_{-0.015}^{+0.013}$$ from the DLS+WMAP9 combination, which, however, is not well constrained when WMAP9 is used alone. The dark energy equation-of-state parameter w is tightly constrained when baryonic acoustic oscillation (BAO) data are added, yielding $$w=-{1.02}_{-0.09}^{+0.10}$$ with the DLS+WMAP9+BAO joint probe. The addition of supernova constraints further tightens the parameter to $$w=-1.03\\pm 0.03$$. Our joint constraints are fully consistent with the final Planck results and also with the predictions of a ΛCDM universe.« less

  17. Four faint T dwarfs from the UKIRT Infrared Deep Sky Survey (UKIDSS) Southern Stripe

    NASA Astrophysics Data System (ADS)

    Chiu, Kuenley; Liu, Michael C.; Jiang, Linhua; Allers, Katelyn N.; Stark, Daniel P.; Bunker, Andrew; Fan, Xiaohui; Glazebrook, Karl; Dupuy, Trent J.

    2008-03-01

    We present the optical and near-infrared photometry and spectroscopy of four faint T dwarfs newly discovered from the UKIDSS first data release. The sample, drawn from an imaged area of ~136 deg2 to a depth of Y = 19.9 (5σ, Vega), is located in the Sloan Digital Sky Survey (SDSS) Southern Equatorial Stripe, a region of significant future deep imaging potential. We detail the selection and followup of these objects, three of which are spectroscopically confirmed brown dwarfs ranging from type T2.5 to T7.5, and one is photometrically identified as early T. Their magnitudes range from Y = 19.01 to 19.88 with derived distances from 34 to 98 pc, making these among the coldest and faintest brown dwarfs known. The T7.5 dwarf appears to be single based on 0.05-arcsec images from Keck laser guide star adaptive optics. The sample brings the total number of T dwarfs found or confirmed by UKIDSS data in this region to nine, and we discuss the projected numbers of dwarfs in the future survey data. We estimate that ~240 early and late T dwarfs are discoverable in the UKIDSS Large Area Survey (LAS) data, falling significantly short of published model projections and suggesting that initial mass functions and/or birth rates may be at the low end of possible models. Thus, deeper optical data have good potential to exploit the UKIDSS survey depth more fully, but may still find the potential Y dwarf sample to be extremely rare.

  18. Cosmic Shear Results from the Deep Lens Survey. II. Full Cosmological Parameter Constraints from Tomography

    NASA Astrophysics Data System (ADS)

    Jee, M. James; Tyson, J. Anthony; Hilbert, Stefan; Schneider, Michael D.; Schmidt, Samuel; Wittman, David

    2016-06-01

    We present a tomographic cosmic shear study from the Deep Lens Survey (DLS), which, providing a limiting magnitude {r}{lim}˜ 27 (5σ ), is designed as a precursor Large Synoptic Survey Telescope (LSST) survey with an emphasis on depth. Using five tomographic redshift bins, we study their auto- and cross-correlations to constrain cosmological parameters. We use a luminosity-dependent nonlinear model to account for the astrophysical systematics originating from intrinsic alignments of galaxy shapes. We find that the cosmological leverage of the DLS is among the highest among existing \\gt 10 deg2 cosmic shear surveys. Combining the DLS tomography with the 9 yr results of the Wilkinson Microwave Anisotropy Probe (WMAP9) gives {{{Ω }}}m={0.293}-0.014+0.012, {σ }8={0.833}-0.018+0.011, {H}0={68.6}-1.2+1.4 {\\text{km s}}-1 {{{Mpc}}}-1, and {{{Ω }}}b=0.0475+/- 0.0012 for ΛCDM, reducing the uncertainties of the WMAP9-only constraints by ˜50%. When we do not assume flatness for ΛCDM, we obtain the curvature constraint {{{Ω }}}k=-{0.010}-0.015+0.013 from the DLS+WMAP9 combination, which, however, is not well constrained when WMAP9 is used alone. The dark energy equation-of-state parameter w is tightly constrained when baryonic acoustic oscillation (BAO) data are added, yielding w=-{1.02}-0.09+0.10 with the DLS+WMAP9+BAO joint probe. The addition of supernova constraints further tightens the parameter to w=-1.03+/- 0.03. Our joint constraints are fully consistent with the final Planck results and also with the predictions of a ΛCDM universe.

  19. Deep Very Large Array Radio Continuum Surveys of GLIMPSE Extended Green Objects (EGOs)

    NASA Astrophysics Data System (ADS)

    Cyganowski, C. J.; Brogan, C. L.; Hunter, T. R.; Churchwell, E.

    2011-12-01

    We present the results of deep, high angular resolution Very Large Array surveys for radio continuum emission toward a sample of 14 GLIMPSE Extended Green Objects (EGOs). Identified as massive young stellar object (MYSO) outflow candidates based on their extended 4.5 μm emission in Spitzer images, the EGOs in our survey sample are also associated with 6.7 GHz Class II and/or 44 GHz Class I CH3OH masers. No continuum is detected at 3.6 or 1.3 cm toward the majority (57%) of our targets (median rms ~0.03 and 0.25 mJy beam-1). Only two EGOs are associated with optically thin emission consistent with ultracompact/compact H II regions. Both of these sources exhibit cm-λ multiplicity, with evidence that one of the less-evolved members may be driving the 4.5 μm outflow. Most of the other cm-λ EGO counterparts are weak (lsim1 mJy), unresolved, undetected at 1.3 cm, and characterized by intermediate spectral indices consistent with hypercompact (HC) H II regions or ionized winds or jets. One EGO centimeter (cm) counterpart, likely an optically thick HC H II region, is detected only at 1.3 cm and is associated with hot core line emission and H2O and 6.7 GHz CH3OH masers. The results of our exceptionally sensitive survey indicate that EGOs signify an early stage of massive star formation, before photoionizing feedback from the central MYSO significantly influences the (proto)cluster environment. Actively driving outflows (and so, presumably, actively accreting), the surveyed EGOs are associated with significant clump-scale gas reservoirs, providing sufficient material for sustained, rapid accretion.

  20. Deep-tow geophysical survey above large exhumed mantle domains of the eastern Southwest Indian ridge

    NASA Astrophysics Data System (ADS)

    Bronner, A.; Munschy, M.; Sauter, D.; Carlut, J.; Searle, R.; Cannat, M.

    2012-04-01

    The recent discovery of a new type of seafloor, the "smooth seafloor", formed with no or very little volcanic activity along the easternmost part of the ultra-slow spreading Southwest Indian ridge (SWIR) shows an unexpected complexity in processes of generation of the oceanic lithosphere. There, detachment faulting is thought to be a mechanism for efficient exhumation of deep-seated mantle rocks. We present here a deep-tow geological-geophysical survey over smooth seafloor at the eastern SWIR (62-64°N) combining multibeam bathymetric data, magnetic data, geology mapping from sidescan sonar (TOBI) images and results from dredge sampling. We introduce a new type of calibration approach for deep-tow fluxgate magnetometer. We show that magnetic data can be corrected from the magnetic effect of the vehicle with no recourse to its attitude (pitch, roll and heading) but only using the 3 components recorded by the magnetometer and an approximation of the scalar intensity of the Earth magnetic field. The collected dredge samples as well as the sidescan sonar images confirm the presence of large areas of exhumed mantle-derived peridodites surrounded by a few volcanic constructions. We investigate the possibility that magnetic anomalies are either caused by serpentinized peridotites and/or magmatic intrusions. We show that the magnetic signature of the smooth seafloor is clearly weaker than the surrounding volcanic areas. Moreover, the calculated magnetization of a source layer as well as the comparison between deep-tow and sea-surface magnetic data argue for strong East-West variability in the distribution of the magnetized sources. This variability may result from fluid-rock interactions along the detachment faults as well as from the occurrence of small sized and thin volcanic patches and thus questions the seafloor spreading origin of the corresponding magnetic anomalies. Finally, we provide magnetic arguments, as calculation of block rotation or spreading asymmetry in

  1. On the nature of infrared-faint radio sources in the Subaru X-ray Deep and Very Large Array-VIMOS VLT Deep Survey fields

    NASA Astrophysics Data System (ADS)

    Singh, Veeresh; Wadadekar, Yogesh; Ishwara-Chandra, C. H.; Sirothia, Sandeep; Sievers, Jonathan; Beelen, Alexandre; Omont, Alain

    2017-10-01

    Infrared-faint radio sources (IFRSs) are an unusual class of objects that are relatively bright at radio wavelengths but have faint or undetected infrared counterparts, even in deep surveys. We identify and investigate the nature of IFRSs using deep radio (S1.4 GHz ˜ 100 μJy beam-1 at 5σ), optical (mr ˜ 26-27.7 at 5σ) and near-infrared (S3.6 μm ˜ 1.3-2.0 μJy beam-1 at 5σ) data that are available in two deep fields: the Subaru X-ray Deep Field (SXDF) and the Very Large Array-VIMOS VLT Deep Survey (VLA-VVDS) field. In 1.8 deg2 of the two fields, we identify a total of nine confirmed and ten candidate IFRSs. We find that our IFRSs are high-redshift radio-loud active galactic nuclei, with 12/19 sources having redshift estimates in the range of z ˜ 1.7-4.3, while a limit of z ≥ 2.0 is placed on the remaining seven sources. Notably, for the first time, our study finds IFRSs with measured redshift >3.0, and also redshift estimates for IFRSs in the faintest 3.6-μm flux regime (i.e. S3.6 μm < 1.3 μJy). Radio observations show that our IFRSs exhibit both compact unresolved and extended double-lobe morphologies, and have predominantly steep radio spectra between 1.4 GHz and 325 MHz. The non-detection of all but one IFRSs in the X-ray band and the optical-to-mid-infrared colour (mr-m24 μm) suggest that a significant fraction of IFRSs are likely to be hosted in dusty obscured galaxies.

  2. The morphology of faint galaxies in Medium Deep Survey images using WFPC2

    NASA Technical Reports Server (NTRS)

    Griffiths, R. E.; Casertano, S.; Ratnatunga, K. U.; Neuschaefer, L. W.; Ellis, R. S.; Gilmore, G. F.; Glazebrook, K.; Santiago, B.; Huchra, J. P.; Windhorst, R. A.

    1994-01-01

    First results from Hubble Space Telescope (HST) Medium Deep Survey images taken with Wide Field/Planetary Camera-2 (WFPC2) demonstrate that galaxy classifications can be reliably performed to magnitudes I814 approximately less than 22.0 in the F815W band. Published spectroscopic surveys to this depth indicate a mean redshift of bar-z approximately 0.5. We have classified over 200 galaxies in nine WFPC2 fields according to a basic morphological scheme. The majority of these faint galaxies appear to be similar to regular Hubble-sequence examples observed at low redshift. To the precision of our classification scheme, the relative proportion of spheroidal and disk systems of normal appearance is as expected from nearby samples, indicating that the bulk of the local galaxy population was in place at half the Hubble time. However, the most intriguing result is the relatively high proportion (approximately 40%) of objects which are in some way anomalous, and which may be of relevance in understanding the origin of the familiar excess population of faint galaxies established by others. These diverse objects include apparently interacting pairs whose multiple structure is only revealed with HST's angular resolution, galaxies with superluminous star-forming regions, diffuse low surface brightness galaxies of various forms, and compact galaxies. These anomalous galaxies contribute a substantial fraction of the excess counts at our limiting magnitude, and may provide insights into the 'faint blue galaxy' problem.

  3. SXDF-ALMA 2-arcmin2 deep survey: 1.1-mm number counts

    NASA Astrophysics Data System (ADS)

    Hatsukade, Bunyo; Kohno, Kotaro; Umehata, Hideki; Aretxaga, Itziar; Caputi, Karina I.; Dunlop, James S.; Ikarashi, Soh; Iono, Daisuke; Ivison, Rob J.; Lee, Minju; Makiya, Ryu; Matsuda, Yuichi; Motohara, Kentaro; Nakanishi, Kouichiro; Ohta, Kouji; Tadaki, Ken-ich; Tamura, Yoichi; Wang, Wei-Hao; Wilson, Grant W.; Yamaguchi, Yuki; Yun, Min S.

    2016-06-01

    We report 1.1-mm number counts revealed with the Atacama Large Millimeter/submillimeter Array (ALMA) in the Subaru/XMM-Newton Deep Survey Field (SXDF). The advent of ALMA enables us to reveal millimeter-wavelength number counts down to the faint end without source confusion. However, previous studies are based on the ensemble of serendipitously detected sources in fields originally targeting different sources and could be biased due to the clustering of sources around the targets. We derive number counts in the flux range of 0.2-2 mJy by using 23 (≥4σ) sources detected in a continuous 2.0-arcmin2 area of the SXDF. The number counts are consistent with previous results within errors, suggesting that the counts derived from serendipitously detected sources are not significantly biased, although there could be field-to-field variation due to the small survey area. By using the best-fitting function of the number counts, we find that ˜40% of the extragalactic background light at 1.1 mm is resolved at S1.1mm > 0.2 mJy.

  4. Deep, Broadband Spectral Line Surveys of Molecule-rich Interstellar Clouds

    NASA Astrophysics Data System (ADS)

    Widicus Weaver, Susanna L.; Laas, Jacob C.; Zou, Luyao; Kroll, Jay A.; Rad, Mary L.; Hays, Brian M.; Sanders, James L.; Lis, Dariusz C.; Cross, Trevor N.; Wehres, Nadine; McGuire, Brett A.; Sumner, Matthew C.

    2017-09-01

    Spectral line surveys are an indispensable tool for exploring the physical and chemical evolution of astrophysical environments due to the vast amount of data that can be obtained in a relatively short amount of time. We present deep, broadband spectral line surveys of 30 interstellar clouds using two broadband λ = 1.3 mm receivers at the Caltech Submillimeter Observatory. This information can be used to probe the influence of physical environment on molecular complexity. We observed a wide variety of sources to examine the relative abundances of organic molecules as they relate to the physical properties of the source (i.e., temperature, density, dynamics, etc.). The spectra are highly sensitive, with noise levels ≤25 mK at a velocity resolution of ˜0.35 km s-1. In the initial analysis presented here, column densities and rotational temperatures have been determined for the molecular species that contribute significantly to the spectral line density in this wavelength regime. We present these results and discuss their implications for complex molecule formation in the interstellar medium.

  5. Disk and Bulge Morphology of WFPC2 Galaxies: The HUBBLE SPACE TELESCOPE Medium Deep Survey

    NASA Astrophysics Data System (ADS)

    Ratnatunga, Kavan U.; Griffiths, Richard E.; Ostrander, Eric J.

    1999-07-01

    Quantitative morphological and structural parameters are estimated for galaxies detected in Hubble Space Telescope observations of WFPC2 survey fields. A modeling approach based on maximum likelihood has been developed for two-dimensional decomposition of faint undersampled galaxy images into components of disk and bulge morphology. Decomposition can be achieved for images down to F814W(I)~23.0, F606W(V)~23.8, and F450W(B)~23.3 mag in WFPC2 exposures of 1 hr. We discuss details of the fitting procedure and present the observed distributions of magnitude, color, effective half-light radius, disk and bulge axis ratios, bulge-to-(disk+bulge) flux ratio, bulge-to-disk half-light radius ratio, and surface brightness. We also discuss the various selection limits on the measured parameters. The Medium Deep Survey catalogs and images of random pure parallel fields and other similar archival primary WFPC2 fields have been made available via the Internet with a searchable browser interface to the database.

  6. The Top 10 List of Gravitational Lens Candidates from the HUBBLE SPACE TELESCOPE Medium Deep Survey

    NASA Astrophysics Data System (ADS)

    Ratnatunga, Kavan U.; Griffiths, Richard E.; Ostrander, Eric J.

    1999-05-01

    A total of 10 good candidates for gravitational lensing have been discovered in the WFPC2 images from the Hubble Space Telescope (HST) Medium Deep Survey (MDS) and archival primary observations. These candidate lenses are unique HST discoveries, i.e., they are faint systems with subarcsecond separations between the lensing objects and the lensed source images. Most of them are difficult objects for ground-based spectroscopic confirmation or for measurement of the lens and source redshifts. Seven are ``strong lens'' candidates that appear to have multiple images of the source. Three are cases in which the single image of the source galaxy has been significantly distorted into an arc. The first two quadruply lensed candidates were reported by Ratnatunga et al. We report on the subsequent eight candidates and describe them with simple models based on the assumption of singular isothermal potentials. Residuals from the simple models for some of the candidates indicate that a more complex model for the potential will probably be required to explain the full structural detail of the observations once they are confirmed to be lenses. We also discuss the effective survey area that was searched for these candidate lens objects.

  7. The VIMOS VLT Deep Survey: Clustering and the Role of Environment in Galaxy Evolution

    NASA Astrophysics Data System (ADS)

    Le Fèvre, O.; Cucciati, O.; Guzzo, L.; Ilbert, O.; Iovino, A.; Marinoni, C.; Meneux, B.; Paltani, S.; Pollo, A.; Bottini, D.; Garilli, B.; Le Brun, V.; Maccagni, D.; Picat, J. P.; Scaramella, R.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnaboldi, M.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; McCracken, H. J.; Marano, B.; Mazure, A.; Merighi, R.; Pellò, R.; Pozzetti, L.; Radovich, M.; Zamorani, G.; Zucca, E.; Bondi, M.; Bongiorno, A.; Busarello, G.; de La Torre, S.; Gregorini, L.; Lamareille, F.; Mathez, G.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2007-12-01

    We present results from the VIMOS VLT Deep Survey on the influence of large scale structures on the evolution of galaxies. The large volume and 11564 galaxies with measured spectroscopic redshifts in the ``First Epoch'' survey enables to study galaxy evolution as a function of local galaxy density and galaxy luminosity or type. We find that the clustering of galaxies is strongly dependent on galaxy types at all redshifts probed, with early spectral type galaxies always more clustered than late-type or irregular galaxies up to z≃1.5. The more luminous galaxies with M_B ≥ -20 are also more strongly clustered than fainter galaxies at all epochs probed up to z≃1.5. From the 3D galaxy density field computed using spectroscopic redshifts, we find a strong evolution of the color-density relation which flattens out with increasing redshifts, with red and blue galaxies becoming equally likely to be found in high density regions probed by the VVDS. At high redshifts 3 ≤ z ≤ 4, we find that the progenitors of the most massive galaxies are more numerous and concentrating more luminosity density than galaxies previously measured at these epochs.

  8. White dwarfs in the UKIRT infrared deep sky survey data release

    SciTech Connect

    Tremblay, P.-E.; Kalirai, J. S.; Leggett, S. K.; Lodieu, N.; Bergeron, P.; Ludwig, H.-G.

    2014-06-20

    We have identified 8 to 10 new cool white dwarfs from the Large Area Survey (LAS) Data Release 9 of the United Kingdom InfraRed Telescope (UKIRT) Infrared Deep Sky Survey (UKIDSS). The data set was paired with the Sloan Digital Sky Survey to obtain proper motions and a broad ugrizYJHK wavelength coverage. Optical spectroscopic observations were secured at Gemini Observatory and confirm the degenerate status for eight of our targets. The final sample includes two additional white dwarf candidates with no spectroscopic observations. We rely on improved one-dimensional model atmospheres and new multi-dimensional simulations with CO5BOLD to review the stellar parameters of the published LAS white dwarf sample along with our additional discoveries. Most of the new objects possess very cool atmospheres with effective temperatures below 5000 K, including two pure-hydrogen remnants with a cooling age between 8.5 and 9.0 Gyr, and tangential velocities in the range 40 km s{sup –1} ≤v {sub tan} ≤ 60 km s{sup –1}. They are likely thick disk 10-11 Gyr old objects. In addition, we find a resolved double degenerate system with v {sub tan} ∼ 155 km s{sup –1} and a cooling age between 3.0 and 5.0 Gyr. These white dwarfs could be disk remnants with a very high velocity or former halo G stars. We also compare the LAS sample with earlier studies of very cool degenerates and observe a similar deficit of helium-dominated atmospheres in the range 5000 < T {sub eff} (K) < 6000. We review the possible explanations for the spectral evolution from helium-dominated toward hydrogen-rich atmospheres at low temperatures.

  9. Cool White Dwarfs Found in the UKIRT Infrared Deep Sky Survey

    NASA Astrophysics Data System (ADS)

    Leggett, S. K.; Lodieu, N.; Tremblay, P.-E.; Bergeron, P.; Nitta, A.

    2011-07-01

    We present the results of a search for cool white dwarfs in the United Kingdom InfraRed Telescope (UKIRT) Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS). The UKIDSS LAS photometry was paired with the Sloan Digital Sky Survey to identify cool hydrogen-rich white dwarf candidates by their neutral optical colors and blue near-infrared colors, as well as faint reduced proper motion magnitudes. Optical spectroscopy was obtained at Gemini Observatory and showed the majority of the candidates to be newly identified cool degenerates, with a small number of G- to K-type (sub)dwarf contaminants. Our initial search of 280 deg2 of sky resulted in seven new white dwarfs with effective temperature T eff ≈ 6000 K. The current follow-up of 1400 deg2 of sky has produced 13 new white dwarfs. Model fits to the photometry show that seven of the newly identified white dwarfs have 4120 K <=T eff <= 4480 K, and cooling ages between 7.3 Gyr and 8.7 Gyr; they have 40 km s-1 <= v tan <= 85 km s-1 and are likely to be thick disk 10-11 Gyr-old objects. The other half of the sample has 4610 K <=T eff <= 5260 K, cooling ages between 4.3 Gyr and 6.9 Gyr, and 60 km s-1 <= v tan <= 100 km s-1. These are either thin disk remnants with unusually high velocities, or lower-mass remnants of thick disk or halo late-F or G stars.

  10. Deep Chandra Survey of the Small Magellanic Cloud. II. Timing Analysis of X-Ray Pulsars

    NASA Astrophysics Data System (ADS)

    Hong, JaeSub; Antoniou, Vallia; Zezas, Andreas; Haberl, Frank; Sasaki, Manami; Drake, Jeremy J.; Plucinsky, Paul P.; Laycock, Silas

    2017-09-01

    We report the timing analysis results of X-ray pulsars from a recent deep Chandra survey of the Small Magellanic Cloud (SMC). We analyzed a total exposure of 1.4 Ms from 31 observations over a 1.2 deg2 region in the SMC under a Chandra X-ray Visionary Program. Using the Lomb–Scargle and epoch-folding techniques, we detected periodic modulations from 20 pulsars and a new candidate pulsar. The survey also covered 11 other pulsars with no clear sign of periodic modulation. The 0.5–8 keV X-ray luminosity (L X ) of the pulsars ranges from 1034 to 1037 erg s‑1 at 60 kpc. All of the Chandra sources with L X ≳ 4 × 1035 erg s‑1 exhibit X-ray pulsations. The X-ray spectra of the SMC pulsars (and high-mass X-ray binaries) are in general harder than those of the SMC field population. All but SXP 8.02 can be fitted by an absorbed power-law model with a photon index of Γ ≲ 1.5. The X-ray spectrum of the known magnetar SXP 8.02 is better fitted with a two-temperature blackbody model. Newly measured pulsation periods of SXP 51.0, SXP 214, and SXP 701, are significantly different from the previous XMM-Newton and RXTE measurements. This survey provides a rich data set for energy-dependent pulse profile modeling. Six pulsars show an almost eclipse-like dip in the pulse profile. Phase-resolved spectral analysis reveals diverse spectral variations during pulsation cycles: e.g., for an absorbed power-law model, some exhibit an (anti)-correlation between absorption and X-ray flux, while others show more intrinsic spectral variation (i.e., changes in photon indices).

  11. White Dwarfs in the UKIRT Infrared Deep Sky Survey Data Release 9

    NASA Astrophysics Data System (ADS)

    Tremblay, P.-E.; Leggett, S. K.; Lodieu, N.; Freytag, B.; Bergeron, P.; Kalirai, J. S.; Ludwig, H.-G.

    2014-06-01

    We have identified 8 to 10 new cool white dwarfs from the Large Area Survey (LAS) Data Release 9 of the United Kingdom InfraRed Telescope (UKIRT) Infrared Deep Sky Survey (UKIDSS). The data set was paired with the Sloan Digital Sky Survey to obtain proper motions and a broad ugrizYJHK wavelength coverage. Optical spectroscopic observations were secured at Gemini Observatory and confirm the degenerate status for eight of our targets. The final sample includes two additional white dwarf candidates with no spectroscopic observations. We rely on improved one-dimensional model atmospheres and new multi-dimensional simulations with CO5BOLD to review the stellar parameters of the published LAS white dwarf sample along with our additional discoveries. Most of the new objects possess very cool atmospheres with effective temperatures below 5000 K, including two pure-hydrogen remnants with a cooling age between 8.5 and 9.0 Gyr, and tangential velocities in the range 40 km s-1 <=v tan <= 60 km s-1. They are likely thick disk 10-11 Gyr old objects. In addition, we find a resolved double degenerate system with v tan ~ 155 km s-1 and a cooling age between 3.0 and 5.0 Gyr. These white dwarfs could be disk remnants with a very high velocity or former halo G stars. We also compare the LAS sample with earlier studies of very cool degenerates and observe a similar deficit of helium-dominated atmospheres in the range 5000 < T eff (K) < 6000. We review the possible explanations for the spectral evolution from helium-dominated toward hydrogen-rich atmospheres at low temperatures.

  12. COOL WHITE DWARFS FOUND IN THE UKIRT INFRARED DEEP SKY SURVEY

    SciTech Connect

    Leggett, S. K.; Nitta, A.; Lodieu, N.

    2011-07-01

    We present the results of a search for cool white dwarfs in the United Kingdom InfraRed Telescope (UKIRT) Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS). The UKIDSS LAS photometry was paired with the Sloan Digital Sky Survey to identify cool hydrogen-rich white dwarf candidates by their neutral optical colors and blue near-infrared colors, as well as faint reduced proper motion magnitudes. Optical spectroscopy was obtained at Gemini Observatory and showed the majority of the candidates to be newly identified cool degenerates, with a small number of G- to K-type (sub)dwarf contaminants. Our initial search of 280 deg{sup 2} of sky resulted in seven new white dwarfs with effective temperature T{sub eff} {approx} 6000 K. The current follow-up of 1400 deg{sup 2} of sky has produced 13 new white dwarfs. Model fits to the photometry show that seven of the newly identified white dwarfs have 4120 K {<=}T{sub eff} {<=} 4480 K, and cooling ages between 7.3 Gyr and 8.7 Gyr; they have 40 km s{sup -1} {<=} v{sub tan} {<=} 85 km s{sup -1} and are likely to be thick disk 10-11 Gyr-old objects. The other half of the sample has 4610 K {<=}T{sub eff} {<=} 5260 K, cooling ages between 4.3 Gyr and 6.9 Gyr, and 60 km s{sup -1} {<=} v{sub tan} {<=} 100 km s{sup -1}. These are either thin disk remnants with unusually high velocities, or lower-mass remnants of thick disk or halo late-F or G stars.

  13. Investigating the Local and High Redshift Universe With Deep Survey Data and Ground-Based Spectroscopy

    NASA Astrophysics Data System (ADS)

    Masters, Daniel Charles

    Large multiwavelength surveys are now driving the frontiers of astronomical research. I describe results from my work using data from two large astronomical surveys: the Cosmic Evolution Survey (COSMOS), which has obtained deep photometric and spectroscopic data on two square degrees of the sky using many of the most powerful telescopes in the world, and the WFC3 Infrared Spectroscopic Parallels (WISP) Survey, which uses the highly sensitive slitless spectroscopic capability of the Hubble Space Telescope Wide Field Camera 3 to detect star-forming galaxies over most of the universe's history. First I describe my work on the evolution of the high-redshift quasar luminosity function, an important observational quantity constraining the growth of the supermassive black holes in the early universe. I show that the number density of faint quasars declines rapidly above z ˜ 3. This result is discussed in the context of cosmic reionization and the coevolution of galaxies and their central black holes. Next I present results of a multi-year campaign of near-infrared spectroscopy with FIRE, a world-class near-infrared spectrometer on the Magellan Baade 6.5 meter telescope in Chile, targeting emission-line galaxies at z ˜ 2 discovered with the Hubble Space Telescope. Our results showed that the typical emission-line galaxy at this redshift has low-metallicity, low dust obscuration, high ionization parameter, and little evidence for significant active galactic nucleus (AGN) contribution to the emission lines. We also find evidence that high redshift star-forming galaxies have enhanced nitrogen abundances. This result has interesting implications for the nature of the star formation in such galaxies -- in particular, it could mean that a large fraction of such galaxies harbor substantial populations of Wolf-Rayet stars, which are massive, evolved stars ejecting large amounts of enriched matter into the interstellar medium. Finally, I will discuss the discovery of three

  14. IDENTIFYING LUMINOUS ACTIVE GALACTIC NUCLEI IN DEEP SURVEYS: REVISED IRAC SELECTION CRITERIA

    SciTech Connect

    Donley, J. L.; Koekemoer, A. M.; Brusa, M.; Salvato, M.; Capak, P.; Cardamone, C. N.; Civano, F.; Ilbert, O.; Impey, C. D.; Kartaltepe, J. S.; Miyaji, T.; Sanders, D. B.; Trump, J. R.

    2012-04-01

    Spitzer/IRAC selection is a powerful tool for identifying luminous active galactic nuclei (AGNs). For deep IRAC data, however, the AGN selection wedges currently in use are heavily contaminated by star-forming galaxies, especially at high redshift. Using the large samples of luminous AGNs and high-redshift star-forming galaxies in COSMOS, we redefine the AGN selection criteria for use in deep IRAC surveys. The new IRAC criteria are designed to be both highly complete and reliable, and incorporate the best aspects of the current AGN selection wedges and of infrared power-law selection while excluding high-redshift star-forming galaxies selected via the BzK, distant red galaxy, Lyman-break galaxy, and submillimeter galaxy criteria. At QSO luminosities of log L{sub 2-10keV}(erg s{sup -1}) {>=}44, the new IRAC criteria recover 75% of the hard X-ray and IRAC-detected XMM-COSMOS sample, yet only 38% of the IRAC AGN candidates have X-ray counterparts, a fraction that rises to 52% in regions with Chandra exposures of 50-160 ks. X-ray stacking of the individually X-ray non-detected AGN candidates leads to a hard X-ray signal indicative of heavily obscured to mildly Compton-thick obscuration (log N{sub H} (cm{sup -2}) = 23.5 {+-} 0.4). While IRAC selection recovers a substantial fraction of luminous unobscured and obscured AGNs, it is incomplete to low-luminosity and host-dominated AGNs.

  15. Identifying Luminous Active Galactic Nuclei in Deep Surveys: Revised IRAC Selection Criteria

    NASA Astrophysics Data System (ADS)

    Donley, J. L.; Koekemoer, A. M.; Brusa, M.; Capak, P.; Cardamone, C. N.; Civano, F.; Ilbert, O.; Impey, C. D.; Kartaltepe, J. S.; Miyaji, T.; Salvato, M.; Sanders, D. B.; Trump, J. R.; Zamorani, G.

    2012-04-01

    Spitzer/IRAC selection is a powerful tool for identifying luminous active galactic nuclei (AGNs). For deep IRAC data, however, the AGN selection wedges currently in use are heavily contaminated by star-forming galaxies, especially at high redshift. Using the large samples of luminous AGNs and high-redshift star-forming galaxies in COSMOS, we redefine the AGN selection criteria for use in deep IRAC surveys. The new IRAC criteria are designed to be both highly complete and reliable, and incorporate the best aspects of the current AGN selection wedges and of infrared power-law selection while excluding high-redshift star-forming galaxies selected via the BzK, distant red galaxy, Lyman-break galaxy, and submillimeter galaxy criteria. At QSO luminosities of log L 2-10 keV(erg s-1) >=44, the new IRAC criteria recover 75% of the hard X-ray and IRAC-detected XMM-COSMOS sample, yet only 38% of the IRAC AGN candidates have X-ray counterparts, a fraction that rises to 52% in regions with Chandra exposures of 50-160 ks. X-ray stacking of the individually X-ray non-detected AGN candidates leads to a hard X-ray signal indicative of heavily obscured to mildly Compton-thick obscuration (log N H (cm-2) = 23.5 ± 0.4). While IRAC selection recovers a substantial fraction of luminous unobscured and obscured AGNs, it is incomplete to low-luminosity and host-dominated AGNs.

  16. The VIMOS-VLT Deep Survey. Luminosity dependence of clustering at z ≃ 1

    NASA Astrophysics Data System (ADS)

    Pollo, A.; Guzzo, L.; Le Fèvre, O.; Meneux, B.; Cappi, A.; Franzetti, P.; Iovino, A.; McCracken, H. J.; Marinoni, C.; Zamorani, G.; Bottini, D.; Garilli, B.; Le Brun, V.; Maccagni, D.; Picat, J. P.; Scaramella, R.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Gavignaud, I.; Ilbert, O.; Marano, B.; Mazure, A.; Merighi, R.; Paltani, S.; Pellò, R.; Pozzetti, L.; Radovich, M.; Zucca, E.; Bondi, M.; Bongiorno, A.; Busarello, G.; Cucciati, O.; Gregorini, L.; Lamareille, F.; Mathez, G.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2006-05-01

    We investigate the dependence of galaxy clustering on the galaxy intrinsic luminosity at high redshift, using the data from the First Epoch VIMOS-VLT Deep Survey (VVDS). The size (6530 galaxies) and depth (IAB<24) of the survey allows us to measure the projected two-point correlation function of galaxies, w_p(r_p), for a set of volume-limited samples up to an effective redshift =0.9 and median absolute magnitude -19.6< MB < -21.3. Fitting w_p(r_p) with a single power-law model for the real-space correlation function ξ(r)=(r/r_0)-γ, we measure the relationship of the correlation length r0 and the slope γ with the sample median luminosity for the first time at such high redshift. Values from our lower-redshift samples (0.1surveys. In our high redshift sample (0.5=-19.6) have a correlation length r_0=2.7+0.3-0.3 h-1 Mpc, compared to r_0=5.0+1.5-1.6 h-1 Mpc at =-21.3. The slope of the correlation function is observed to correspondingly steepen significantly from γ=1.6+0.1-0.1 to γ=2.4+0.4-0.2. This is not observed either by large local surveys or in our lower-redshift samples and seems to imply a significant change in the way luminous galaxies trace dark-matter halos at z˜ 1 with respect to z˜ 0. At our effective median redshift z ≃ 0.9 this corresponds to a strong difference of the relative bias, from b/b* < 0.7 for galaxies with L < L* to b/b* ≃ 1.4 for galaxies with L > L*.

  17. A first deep seismic survey in the Sea of Marmara: Deep basins and whole crust architecture and evolution

    NASA Astrophysics Data System (ADS)

    Laigle, Mireille; Becel, Anne; de Voogd, Béatrice; Hirn, Alfred; Taymaz, Tuncay; Ozalaybey, Serdar; Members Of Seismarmara Leg1 Team

    2008-06-01

    Increased source strength, streamer length and dense spatial coverage of seismic reflection profiles of the SEISMARMARA Leg 1 allow to image the deep structure of the marine North Marmara Trough (NMT) on the strike-slip North Anatolian Fault (NAF) west of the destructive Izmit 1999 earthquake. A reflective lower crust and the Moho boundary are detected. They appear upwarped on an E-W profile from the southern Central Basin eastwards, towards more internal parts of the deformed region. Thinning of the upper crust could use a detachment suggested from an imaged dipping intracrustal reflector that would allow upper crustal material to be dragged from beneath it and above the lower crust, accounting for the extensional component but also southwest motion of the southern margin of the NMT. Sections across the eastern half of the NMT, crossing the Cinarcik and Imrali basins, reveal several faults that are active reaching into the basement and have varying strike and proportions of normal and strike-slip displacement. They might be viewed as petals of a large scale negative flower-structure that spreads over a width of 30 km at surface and is rooted deeper in the lithosphere. Under the Central Basin a very thick sediment infill is revealed and its extensional bounding faults are active and imaged as much as 8 km apart down to 6 km depth. We interpret them as two deep-rooted faults encompassing a foundering basement block, rather than being merely pulled-apart from a jog in a strike-slip above a décollement. The deep-basin lengthening would account for only a modest part of the proposed 60 km finite motion since 4 Myr along the same direction oblique to the NMT that sidesteps the shear motion from its two ends. Thus differential motion occurred much beyond the deep basins, like subsidence involving the NMT bounding faults and the intracrustal detachments. The complex partitioned motion localized on active faults with diverse natures and orientations is suggested to

  18. SCORPIO: a deep survey of radio emission from the stellar life-cycle

    NASA Astrophysics Data System (ADS)

    Umana, G.; Trigilio, C.; Franzen, T. M. O.; Norris, R. P.; Leto, P.; Ingallinera, A.; Buemi, C. S.; Agliozzo, C.; Cavallaro, F.; Cerrigone, L.

    2015-11-01

    Radio emission has been detected in a broad variety of stellar objects from all stages of stellar evolution. However, most of our knowledge originates from targeted observations of small samples, which are strongly biased to sources which are peculiar at other wavelengths. In order to tackle this problem we have conducted a deep 1.4 GHz survey by using the Australian Telescope Compact Array, with a net bandwidth of 1.7 GHz (1.4-3.1 GHz) , following the same observing setup as that used for the Australia Telescope Large Area Survey project, this time choosing a region more appropriate for stellar work. In this paper, the Stellar Continuum Originating from Radio Physics In Ourgalaxy (SCORPIO) project is presented as well as results from the pilot experiment. The achieved rms is 30 μJy and the angular resolution ˜10 arcsec. 614 point-like sources have been extracted just from the pilot field. Only 34 of them are classified in SIMBAD or the NASA/IPAC Extragalactic Database. About 80 per cent of the extracted sources are reported in one of the inspected catalogues and 50 per cent of them appears to belong to a reddened stellar/Galactic population. However, the evaluation of extragalactic contaminants is very difficult without further investigations. Interesting results have been obtained for extended radio sources that fall in the SCORPIO field. Many roundish-like structures (indicated as bubbles in the following) have been found, some of which are classified at other wavelengths. However, for all of these sources, our project has provided us with images of unprecedented sensitivity and angular resolution.

  19. Tracing Evolution of Starbursts and AGNs using Ultra-deep Radio and mm/smm Surveys

    NASA Astrophysics Data System (ADS)

    Yun, Min S.; Gim, Hansung; Morrison, Glenn; Hales, Christopher A.; Momjian, Emmanuel; Owen, Frazer; Kellermann, Ken; Aretxaga, Itziar; Giavalisco, Mauro; Hughes, David; Lowenthal, James; Miller, Neal; Kawabe, Ryohei; Kohno, Kotaro

    2015-08-01

    There is growing evidence supporting a rapid build up of metals among massive galaxies during their rapid growth via an intense starburst in the early epochs. These star formation activities may be largely obscured in the UV and optical light, as in the local universe. If the growth of supermassive blackholes occurs at or nearly the same time, the accompanying AGN activity may also be heavily obscured. Ultra-deep surveys in the radio and far-infrared can offer extinction-free view of these systems, and the advent of new facilities such as the Jansky VLA, ALMA, and LMT now allows us to probe directly the population of starburst galaxies that are responsible for the bulk of the stellar mass build-up during the epoch of galaxy growth (SFR > 10-100 M⊙/yr at z≈2 or earlier). We will present our analysis of the properties of the micro-Jansky radio sources identified by new Jansky VLA surveys of the GOODS and COSMOS fields using the rich archival data already available (Herschel, Spitzer, Chandra, ALMA, LMT, etc.). Specifically, we find evidence for two populations of microJy radio sources with distinct spectral index distribution. We explore whether this reflects differences in the underlying powering mechanisms by examining their radio-FIR correlation and X-ray properties. We also find the previously reported apparent systematic change in the "q-value" with increasing redshift, and we examine the reality of this trend in some detail. Finally, we will also examine the spatial extent of activities for a subset of the sample where high angular resolution (better than 1") information is available.

  20. A Systematic Survey of Protoclusters at z ~ 3-6 in the CFHTLS Deep Fields

    NASA Astrophysics Data System (ADS)

    Toshikawa, Jun; Kashikawa, Nobunari; Overzier, Roderik; Malkan, Matthew A.; Furusawa, Hisanori; Ishikawa, Shogo; Onoue, Masafusa; Ota, Kazuaki; Tanaka, Masayuki; Niino, Yuu; Uchiyama, Hisakazu

    2016-08-01

    We present the discovery of three protoclusters at z ˜ 3-4 with spectroscopic confirmation in the Canada-France-Hawaii Telescope Legacy Survey Deep Fields. In these fields, we investigate the large-scale projected sky distribution of z ˜ 3-6 Lyman-break galaxies and identify 21 protocluster candidates from regions that are overdense at more than 4σ overdensity significance. Based on cosmological simulations, it is expected that more than 76% of these candidates will evolve into a galaxy cluster of at least a halo mass of 1014 M ⊙ at z = 0. We perform follow-up spectroscopy for eight of the candidates using Subaru/FOCAS, Keck II/DEIMOS, and Gemini-N/GMOS. In total we target 462 dropout candidates and obtain 138 spectroscopic redshifts. We confirm three real protoclusters at z = 3-4 with more than five members spectroscopically identified and find one to be an incidental overdense region by mere chance alignment. The other four candidate regions at z ˜ 5-6 require more spectroscopic follow-up in order to be conclusive. A z = 3.67 protocluster, which has 11 spectroscopically confirmed members, shows a remarkable core-like structure composed of a central small region (<0.5 physical Mpc) and an outskirts region (˜1.0 physical Mpc). The Lyα equivalent widths of members of the protocluster are significantly smaller than those of field galaxies at the same redshift, while there is no difference in the UV luminosity distributions. These results imply that some environmental effects start operating as early as at z ˜ 4 along with the growth of the protocluster structure. This study provides an important benchmark for our analysis of protoclusters in the upcoming Subaru/HSC imaging survey and its spectroscopic follow-up with the Subaru/PFS that will detect thousands of protoclusters up to z ˜ 6.

  1. Properties of Field Galaxies to I=22 from the Medium Deep Survey

    NASA Astrophysics Data System (ADS)

    Phillips, A. C.; Forbes, D. A.; Gronwall, C.; Illingworth, G. D.; Koo, D. C.; Griffiths, R. E.; Ratnatunga, K.; Ellis, R. S.; Green, R. F.; Huchra, J. P.; Tyson, J. A.; Windhorst, R. A.

    1994-12-01

    We present a complete sample of 72 I≲ 22 field galaxies from two fields observed with the WFPC-II as part of the Medium Deep Survey. Basic observable parameters (I and V photometry, sizes and intensity profiles) have been measured, and are discussed in the context of morphological type and apparent structural peculiarities. The median redshift of the sample is expected to be z ~ 0.5. Despite lookback times approaching half the age of the universe, we find little evidence for strong evolutionary effects. In particular, we see no extreme color gradients in the galaxies. The size-vs-magnitude relationship shows no indication that this distant sample differs strongly from the local galaxy population, beyond changes predicted by passive evolution and assuming a local luminosity function improved from that of Koo, Gronwall & Bruzual (1993). (This work was supported by NASA/HST grants GO-2684-0*-94A from STScI, which is operated by AURA, Inc., under NASA contract NAS5-26555.)

  2. DEEP NEAR-INFRARED SURVEY OF THE PIPE NEBULA. II. DATA, METHODS, AND DUST EXTINCTION MAPS

    SciTech Connect

    Roman-Zuniga, Carlos G.; Lada, Charles J.; Lombardi, Marco

    2010-12-20

    We present a new set of high-resolution dust extinction maps of the nearby and essentially starless Pipe Nebula molecular cloud. The maps were constructed from a concerted deep near-infrared imaging survey with the ESO-VLT, ESO-NTT, CAHA 3.5 m telescopes, and 2MASS data. The new maps have a resolution three times higher than the previous extinction map of this cloud by Lombardi et al. and are able to resolve structures down to 2600 AU. We detect 244 significant extinction peaks across the cloud. These peaks have masses between 0.1 and 18.4 M{sub sun}, diameters between 1.2 and 5.7 x 10{sup 4} AU (0.06 and 0.28 pc), and mean densities of about 10{sup 4} cm{sup -3}, all in good agreement with previous results. From the analysis of the mean surface density of companions we find a well-defined scale near 1.4 x 10{sup 4} AU below which we detect a significant decrease in structure of the cloud. This scale is smaller than the Jeans length calculated from the mean density of the peaks. The surface density of peaks is not uniform but instead it displays clustering. Extinction peaks in the Pipe Nebula appear to have a spatial distribution similar to the stars in Taurus, suggesting that the spatial distribution of stars evolves directly from the primordial spatial distribution of high-density material.

  3. Targeting of the Subthalamic Nucleus for Deep Brain Stimulation: A Survey Among Parkinson Disease Specialists.

    PubMed

    Hamel, Wolfgang; Köppen, Johannes A; Alesch, François; Antonini, Angelo; Barcia, Juan A; Bergman, Hagai; Chabardes, Stephan; Contarino, Maria Fiorella; Cornu, Philippe; Demmel, Walter; Deuschl, Günther; Fasano, Alfonso; Kühn, Andrea A; Limousin, Patricia; McIntyre, Cameron C; Mehdorn, H Maximilian; Pilleri, Manuela; Pollak, Pierre; Rodríguez-Oroz, Maria C; Rumià, Jordi; Samuel, Michael; Timmermann, Lars; Valldeoriola, Francesc; Vesper, Jan; Visser-Vandewalle, Veerle; Volkmann, Jens; Lozano, Andres M

    2017-03-01

    Deep brain stimulation within or adjacent to the subthalamic nucleus (STN) represents the most common stereotactic procedure performed for Parkinson disease. Better STN imaging is often regarded as a requirement for improving stereotactic targeting. However, it is unclear whether there is consensus about the optimal target. To obtain an expert opinion on the site regarded optimal for "STN stimulation," movement disorder specialists were asked to indicate their preferred position for an active contact on hard copies of the Schaltenbrand and Wahren atlas depicting the STN in all 3 planes. This represented an idealized setting, and it mimicked optimal imaging for direct target definition in a perfectly delineated STN. The suggested targets were heterogeneous, although some clustering was observed in the dorsolateral STN and subthalamic area. In particular, in the anteroposterior direction, the intended targets differed to a great extent. Most of the indicated targets are thought to also result in concomitant stimulation of structures adjacent to the STN, including the zona incerta, fields of Forel, and internal capsule. This survey illustrates that most sites regarded as optimal for STN stimulation are close to each other, but there appears to be no uniform perception of the optimal anatomic target, possibly influencing surgical results. The anatomic sweet zone for STN stimulation needs further specification, as this information is likely to make magnetic resonance imaging-based target definition less variable when applied to individual patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. X-ray Properties of Clusters from the Palomar Deep Survey

    NASA Astrophysics Data System (ADS)

    Holden, B. H.; Nichol, B. C.; Romer, A. K.; Ulmer, M. P.

    1996-05-01

    Twenty of the 79 z>0.2 distant, optically selected, cluster candidates in the Palomar Deep Cluster Survey (Postman et al. 1996) were serendipitously observed by the ROSAT satellite. We have reduced the three PSPC pointings that overlapped Postman et al. (1996) fields using the Snowden et al. (1994) Extended X-ray Analysis Software and a wavelet analysis source detection algorithm. We derive count rates for the cluster candidates inside a metric aperture defined by the estimate redshift quoted in Postman et al. (1996). We find all 20 clusters observed by the PSPC to be X-ray faint; only 4 were detected at >3sigma . The luminosities derived from the measured/upper-limit count rates are significantly lower than those predicted from the richness vs luminosity distribution derived for X-ray selected clusters (Edge & Stewart 1991). This discrepancy cannot be wholly attributed to projection effects; according to Postman et al. (1996) less than 30% of their objects are ``phantom clusters''. We will present evidence to support our conclusion that optically selected clusters are younger and less evolved than their X-ray selected counterparts.

  5. A Deep Multicolor Survey. II. Initial Spectroscopy and Comparison with Expected Quasar Number Counts: Erratum

    NASA Astrophysics Data System (ADS)

    Hall, Patrick B.; Osmer, Patrick S.; Green, Richard F.; Porter, Alain C.; Warren, Stephen J.

    1996-11-01

    In the paper "A Deep Multicolor Survey. II. Initial Spectroscopy and Comparison with Expected Quasar Number Counts" by Patrick B. Hall, Patrick S. Osmer, Richard F. Green, Alain C. Porter, and Stephen J. Warren (ApJ, 462,614 [1996]), some of the figures were inadvertently printed with poor resolution. The full information conveyed in the images is thus difficult to perceive. Here we present high-resolution versions of the affected figures (Fig. 1 and Figs. 10-15). In all diagrams, objects from the catalog are plotted as error bars, with only half the full error bars plotted, for clarity. Error ban extending off the diagram indicate upper limits. Spectroscopically confirmed quasars, compact narrow emission-line galaxies (CNELGs), and stars are plotted as filled boxes, open boxes, and inverted triangles, respectively. Spectroscopically observed but unidentified candidates are plotted as crosses and simulated quasar colors as dots. The line of simulated quasar points at U- V = 3.0 in Figure 11a and the similar lines in other color-color diagrams indicate that the simulated colors are lower limits. The reader should also note that Figures 16b and 16c were incorrectly switched with each other in the paper.

  6. A sub-millimetre survey of dust enshrouded galaxies in the Hubble Deep Field region

    NASA Astrophysics Data System (ADS)

    Borys, Colin James Kelvin

    This thesis investigates the emission of sub-millimetre- wave radiation from galaxies in the Hubble Deep Field North region. The data were obtained from dedicated observing runs from our group and others using the SCUBA camera on the James Clerk Maxwell Telescope. The data were combined using techniques specifically developed here for low signal-to-noise source recovery. The sources found represent over 10% of all cosmological sources SCUBA has detected since it was commissioned. The number of sub-mm galaxies we detect account for a significant fraction of the sub-mm back-ground, and we show that mild extrapolations can reproduce it entirely. We comment on their clustering properties, both with themselves and other high-redshift galaxy types. A multi-wavelength analysis of these galaxies shows that SCUBA sources do not all have similar properties, and are made of a collection including: star-forming radio galaxies; optically invisible objects; active galactic nuclei; and extremely red objects. Reasonable attempts to determine the redshift distribution of the sample show that SCUBA galaxies have a median redshift of around 2, and suggest that the global star formation rate may be dominated by such objects at redshifts beyond about 1. The thesis summarises the current state of extra-galactic sub-mm astronomy, and comments on how new surveys and detectors will allow us to place stronger constraints on the evolution properties of the high-redshift Universe.

  7. Measuring M Dwarf Rotation in the Pan-STARRS 1 Medium Deep Survey

    NASA Astrophysics Data System (ADS)

    Fong, Erin R.; Williams, Peter K. G.; Berger, Edo

    2016-01-01

    The rise of large-format CCDs and automated detection methods has greatly increased the tractability of large-scale studies of stellar rotation. Studies of the relationship between stellar rotation and magnetic activity show a strong correlation, supporting the concept of a rotationally-driven dynamo. However, the number of confirmed rotation periods for stars in the fully convective regime, whose magnetic dynamos are less well understood, remains low. Here we report on ongoing work to measure rotation periods for the M dwarf stellar population observed by the Pan-STARRS 1 Medium Deep Survey (PS1/MDS). We refine an initial sample of around 4.3 million sources using color cuts in each of the five Pan-STARRS 1 filters. Of these sources, we estimate there to be around 135,000 sources which are candidate M dwarfs with a spectral type of M1 or higher. We discuss the outcomes of various rotation period detection methods and present preliminary results. This work is supported in part by the National Science Foundation REU and Department of Defense ASSURE programs under NSF Grant no. 1262851 and by the Smithsonian Institution.

  8. The VIMOS VLT Deep Survey. Testing the gravitational instability paradigm at z ~ 1

    NASA Astrophysics Data System (ADS)

    Marinoni, C.; Guzzo, L.; Cappi, A.; Le Fèvre, O.; Mazure, A.; Meneux, B.; Pollo, A.; Iovino, A.; McCracken, H. J.; Scaramella, R.; de la Torre, S.; Virey, J. M.; Bottini, D.; Garilli, B.; Le Brun, V.; Maccagni, D.; Picat, J. P.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Ilbert, O.; Lamareille, F.; Marano, B.; Mathez, G.; Merighi, R.; Paltani, S.; Pellò, R.; Pozzetti, L.; Radovich, M.; Vergani, D.; Zamorani, G.; Zucca, E.; Abbas, U.; Bondi, M.; Bongiorno, A.; Brinchmann, J.; Buzzi, A.; Cucciati, O.; de Ravel, L.; Gregorini, L.; Mellier, Y.; Merluzzi, P.; Perez-Montero, E.; Taxil, P.; Temporin, S.; Walcher, C. J.

    2008-08-01

    We have reconstructed the three-dimensional density fluctuation maps to z˜ 1.5 using the distribution of galaxies observed in the VVDS-Deep survey. We use this overdensity field to measure the evolution of the probability distribution function and its lower-order moments over the redshift interval 0.7< z <1.5. We apply a self-consistent reconstruction scheme which includes a complete non-linear description of galaxy biasing and which has been thoroughly tested on realistic mock samples. We find that the variance and skewness of the galaxy distribution evolve over this redshift interval in a way that is remarkably consistent with predictions of first- and second-order perturbation theory. This finding confirms the standard gravitational instability paradigm over nearly 9 Gyr of cosmic time and demonstrates the importance of accounting for the non-linear component of galaxy biasing to consistently reproduce the higher-order moments of the galaxy distribution and their evolution.

  9. The VIMOS VLT Deep Survey: the build-up of the colour-density relation

    NASA Astrophysics Data System (ADS)

    Cucciati, O.; Iovino, A.; Marinoni, C.; Ilbert, O.; Bardelli, S.; Franzetti, P.; Le Fèvre, O.; Pollo, A.; Zamorani, G.; Cappi, A.; Guzzo, L.; McCracken, H. J.; Meneux, B.; Scaramella, R.; Scodeggio, M.; Tresse, L.; Zucca, E.; Bottini, D.; Garilli, B.; Le Brun, V.; Maccagni, D.; Picat, J. P.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnaboldi, M.; Arnouts, S.; Bolzonella, M.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Gavignaud, I.; Marano, B.; Mazure, A.; Merighi, R.; Paltani, S.; Pellò, R.; Pozzetti, L.; Radovich, M.; Bondi, M.; Bongiorno, A.; Busarello, G.; de la Torre, S.; Gregorini, L.; Lamareille, F.; Mathez, G.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.; Temporin, S.; Vergani, D.

    2006-10-01

    We investigate the redshift and luminosity evolution of the galaxy colour-density relation using the data from the First Epoch VIMOS-VLT Deep Survey (VVDS). The size (6582 galaxies with good quality redshifts), depth (IAB≤ 24) and redshift sampling rate (20% on the mean) of the survey enable us to reconstruct the 3D galaxy environment on relatively local scales (R=5 h-1 Mpc) up to redshift z ˜ 1.5. Particular attention has been devoted to calibrate a density reconstruction scheme, which factors out survey selection effects and reproduces in an unbiased way the underlying "real" galaxy environment. We find that the colour-density relation shows a dramatic change as a function of cosmic time. While at lower redshift we confirm the existence of a steep colour-density relation, with the fraction of the reddest(/bluest) galaxies of the same luminosity increasing(/decreasing) as a function of density, this trend progressively disappears in the highest redshift bins investigated. Our results suggest the existence of an epoch (more remote for brighter galaxies) characterized by the absence of the colour-density relation on the R=5 h-1 Mpc scales investigated. The rest frame u*-g' colour-magnitude diagram shows a bimodal pattern in both low and high density environments up to redshift z˜ 1.5. We find that the bimodal distribution is not universal but strongly depends upon environment: at lower redshifts the colour-magnitude diagrams in low and high density regions are significantly different while the progressive weakening of the colour-density relation causes the two bimodal distributions to nearly mirror each other in the highest redshift bin investigated. Both the colour-density and the colour-magnitude-density relations, on the R=5 h-1 Mpc scales, appear to be a transient, cumulative product of genetic and environmental factors that have been operating over at least a period of 9 Gyr. These findings support an evolutionary scenario in which star formation

  10. The Taiwan ECDFS Near-Infrared Survey: Ultra-deep J and KS Imaging in the Extended Chandra Deep Field-South

    NASA Astrophysics Data System (ADS)

    Hsieh, Bau-Ching; Wang, Wei-Hao; Hsieh, Chih-Chiang; Lin, Lihwai; Yan, Haojing; Lim, Jeremy; Ho, Paul T. P.

    2012-12-01

    We present ultra-deep J and KS imaging observations covering a 30' × 30' area of the Extended Chandra Deep Field-South (ECDFS) carried out by our Taiwan ECDFS Near-Infrared Survey (TENIS). The median 5σ limiting magnitudes for all detected objects in the ECDFS reach 24.5 and 23.9 mag (AB) for J and KS , respectively. In the inner 400 arcmin2 region where the sensitivity is more uniform, objects as faint as 25.6 and 25.0 mag are detected at 5σ. Thus, this is by far the deepest J and KS data sets available for the ECDFS. To combine TENIS with the Spitzer IRAC data for obtaining better spectral energy distributions of high-redshift objects, we developed a novel deconvolution technique (IRACLEAN) to accurately estimate the IRAC fluxes. IRACLEAN can minimize the effect of blending in the IRAC images caused by the large point-spread functions and reduce the confusion noise. We applied IRACLEAN to the images from the Spitzer IRAC/MUSYC Public Legacy in the ECDFS survey (SIMPLE) and generated a J+KS -selected multi-wavelength catalog including the photometry of both the TENIS near-infrared and the SIMPLE IRAC data. We publicly release the data products derived from this work, including the J and KS images and the J+KS -selected multi-wavelength catalog.

  11. IMPROVED MOCK GALAXY CATALOGS FOR THE DEEP2 GALAXY REDSHIFT SURVEY FROM SUBHALO ABUNDANCE AND ENVIRONMENT MATCHING

    SciTech Connect

    Gerke, Brian F.; Wechsler, Risa H.; Behroozi, Peter S.; Yan, Renbin; Coil, Alison L.

    2013-09-15

    We develop empirical methods for modeling the galaxy population and populating cosmological N-body simulations with mock galaxies according to the observed properties of galaxies in survey data. We use these techniques to produce a new set of mock catalogs for the DEEP2 Galaxy Redshift Survey based on the output of the high-resolution Bolshoi simulation, as well as two other simulations with different cosmological parameters, all of which we release for public use. The mock-catalog creation technique uses subhalo abundance matching to assign galaxy luminosities to simulated dark-matter halos. It then adds color information to the resulting mock galaxies in a manner that depends on the local galaxy density, in order to reproduce the measured color-environment relation in the data. In the course of constructing the catalogs, we test various models for including scatter in the relation between halo mass and galaxy luminosity, within the abundance-matching framework. We find that there is no constant-scatter model that can simultaneously reproduce both the luminosity function and the autocorrelation function of DEEP2. This result has implications for galaxy-formation theory, and it restricts the range of contexts in which the mock catalogs can be usefully applied. Nevertheless, careful comparisons show that our new mock catalogs accurately reproduce a wide range of the other properties of the DEEP2 catalog, suggesting that they can be used to gain a detailed understanding of various selection effects in DEEP2.

  12. Enhancing the Legacy of Spitzer and Herschel with the MOSFIRE Deep Evolution Field Survey

    NASA Astrophysics Data System (ADS)

    Reddy, Naveen

    The next frontier for comprehensive galaxy surveys is the epoch at z~1.5-3.5, the peak of star formation and black hole activity. Despite the new windows that Spitzer and Herschel have opened up into the stellar and dust emission of distant galaxies and AGN during this key epoch, these studies have been limited by the lack of spectroscopic redshifts and the unknown physical conditions (e.g., metallicities, ionization) within the targeted galaxies. To realize the full potential of Spitzer and Herschel, we require a large spectroscopic survey that will: (a) efficiently assemble spectroscopic redshifts for large samples of galaxies at z=1.4-3.8; (b) yield the physical conditions, including the ionization and metallicities of these galaxies; and (c) easily obtain spectroscopic redshifts even for very dusty/confused galaxies. To this end, our team has been allocated a large program of 47 Keck nights with the multi-object near-IR spectrograph MOSFIRE to carry out the MOSFIRE Deep Evolution Field Survey (MOSDEF) in three of the Hubble CANDELS fields. MOSDEF will obtain rest-optical spectra of ~1500 galaxies at redshifts z=1.4-3.8, targeting many of the optical nebular emission lines and continuum features (e.g., [OII], [OIII], H-beta, H-alpha, [NII], [SII], 4000 Angstrom break, Ca H and K, and Mbg) that until now have been inaccessible for large samples of distant galaxies, but which are routinely used to measure the SFRs, dust attenuation, metal and gas content, and ionization and dynamical properties in nearby galaxies. MOSDEF spectroscopy provides a critical supporting role for the analysis of Spitzer and Herschel observations of distant galaxies. With this transformative dataset, we will perform the following analyses. First, we will use Spitzer and Herschel imaging, aided with spectroscopic redshifts from MOSDEF, to construct individual and mean dust SEDs for galaxies at redshifts 1.4

  13. X-ray selected galaxy clusters in the Pan-STARRS Medium Deep Survey

    NASA Astrophysics Data System (ADS)

    Ebeling, H.; Edge, A. C.; Burgett, W. S.; Chambers, K. C.; Hodapp, K. W.; Huber, M. E.; Kaiser, N.; Price, P. A.; Tonry, J. L.

    2013-06-01

    We present the results of a pilot study for the extended Massive Cluster Survey (eMACS), a comprehensive search for distant, X-ray luminous galaxy clusters at z > 0.5. Our pilot study applies the eMACS concept to the 71 deg2 area extended by the 10 fields of the Pan-STARRS1 (PS1) Medium Deep Survey (MDS). Candidate clusters are identified by visual inspection of PS1 images in the g, r, i and z bands in a 5 × 5 arcmin2 region around X-ray sources detected in the ROSAT All-Sky Survey (RASS). To test and optimize the eMACS X-ray selection criteria, our pilot study uses the largest possible RASS data base, i.e. all RASS sources listed in the Bright and Faint Source Catalogues (BSC and FSC) that fall within the MDS footprint. We apply no additional constraints regarding X-ray flux, spectral hardness ratio or photon statistics and lower the redshift threshold to z > 0.3 to extend the probed luminosity range to poorer systems. Scrutiny of PS1/MDS images for 41 BSC and 200 FSC sources combined with dedicated spectroscopic follow-up observations results in a sample of 11 clusters with estimated or spectroscopic redshifts of z > 0.3. In order to assess and quantify the degree of point source contamination of the observed RASS fluxes, we examine archival Chandra data obtained in targeted and serendipitous observations of six of the 11 clusters found. As expected, the diffuse emission from all six systems is contaminated by point sources to some degree, and for half of them active galactic nucleus emission dominates. X-ray follow-up observations will thus be crucial in order to establish robust cluster luminosities for eMACS clusters. Although the small number of distant X-ray luminous clusters in the MDS does not allow us to make firm predictions for the over 20 000 deg2 of extragalactic sky covered by eMACS, the identification of two extremely promising eMACS cluster candidates at z ≳ 0.6 (both yet to be observed with Chandra) in such a small solid angle is encouraging

  14. A Rapid Radiocarbon Method for Age Surveys of Southern Ocean Deep-sea Corals

    NASA Astrophysics Data System (ADS)

    Burke, A.; Robinson, L. F.; Gerlach, D. S.; Jenkins, W. J.; McNichol, A. P.

    2008-12-01

    Deep-sea corals provide a unique archive of past ocean radiocarbon because they are sessile and can be dated independently using U-series nuclides. One difficulty, however, is that using current techniques it is impractical to date large numbers of corals in order to determine which specimens have the appropriate ages for radiocarbon reconstructions. Here we present results from a quick method of making graphite for radiocarbon dating that reduces the amount of sample preparation time, thus allowing us to date a greater number of corals. In addition, these rapid age surveys provide important information on coral age populations, allowing us to examine coral distributions through time. The corals used in this study come from a sample set of about 6,000 specimens of Flabellum, Balanophyllia and Desmophyllum spp. collected from the Drake Passage area (50S -70S, 120 m-1700 m depth). Replicate samples from a single coral yielded a standard deviation of 81 years (n=9). Variations in sample mass (3 to 85 mg) have no clear effect on the Fm and furthermore, a simple cleaning using methanol yields the same results as a more involved cleaning procedure that includes an oxidizing solution and perchloric acid rinse. To improve the efficiency of the method, we assumed a delta13C = 0 per mil. This assumption is likely our largest source of uncertainty, resulting in offsets of up to 200 radiocarbon years over a reasonable range of delta13C. This level of uncertainty is sufficiently low to allow distinction between corals from different time periods over the past 35 ky (e.g. Last Glacial Maximum, Younger Dryas, etc.). To date, we have found corals from Burdwood Bank dating from the modern to the Younger Dryas and corals from the Drake Passage dating from the modern to Heinrich Event 1, which will be used in future paleo-climatic reconstructions in this important part of the ocean.

  15. Assessing the deep drilling potential of Lago de Tota, Colombia, with a seismic survey

    NASA Astrophysics Data System (ADS)

    Bird, B. W.; Wattrus, N. J.; Fonseca, H.; Velasco, F.; Escobar, J.

    2015-12-01

    Reconciling orbital-scale patterns of inter-hemispheric South American climate during the Quaternary requires continuous, high-resolution paleoclimate records that span multiple glacial cycles from both hemispheres. Southern Andean Quaternary climates are represented by multi-proxy results from Lake Titicaca (Peru-Bolivia) spanning the last 400 ka and by pending results from the Lago Junin Drilling Project (Peru). Although Northern Andean sediment records spanning the last few million years have been retrieved from the Bogota and Fúquene Basins in the Eastern Cordillera of the Colombian Andes, climatic reconstructions based on these cores have thus far been limited to pollen-based investigations. When viewed together with the Southern Hemisphere results, these records suggest an anti-phased hemispheric climatic response during glacial cycles. In order to better assess orbital-scale climate responses, however, independent temperature and hydroclimate proxies from the Northern Hemisphere are needed in addition to vegetation histories. As part of this objective, an effort is underway to develop a paleoclimate record from Lago de Tota (3030 m asl), the largest lake in Colombia and the third largest lake in the Andes. One of 17 highland tectonic basins in Eastern Cordillera, Lago de Tota formed during Tertiary uplift that deformed pre-foreland megasequences, synrift and back-arc megasequences. The precise age and thickness of sediments in the Lago de Tota basin has not previously been established. Here, we present results from a recent single-channel seismic reflection survey collected with a small (5 cubic inch) air gun and high-resolution CHIRP sub-bottom data. With these data, we examine the depositional history and sequence stratigraphy of Lago de Tota and assess its potential as a deep drilling target.

  16. A DEEP RADIO SURVEY OF HARD STATE AND QUIESCENT BLACK HOLE X-RAY BINARIES

    SciTech Connect

    Miller-Jones, J. C. A.; Jonker, P. G.; Maccarone, T. J.; Calvelo, D. E.; Nelemans, G.

    2011-09-20

    We have conducted a deep radio survey of a sample of black hole X-ray binaries in the hard and quiescent states to determine whether any systems were sufficiently bright for astrometric follow-up with high-sensitivity very long baseline interferometric arrays. The one hard-state system, Swift J1753.5-0127, was detected at a level of 0.5 mJy beam{sup -1}. All 11 quiescent systems were not detected. In the three cases with the highest predicted quiescent radio brightnesses (GRO J0422+32, XTE J1118+480, and GRO J1655-40), the new capabilities of the Expanded Very Large Array were used to reach noise levels as low as 2.6 {mu}Jy beam{sup -1}. None of the three sources were detected to 3{sigma} upper limits of 8.3, 7.8, and 14.2 {mu}Jy beam{sup -1}, respectively. These observations represent the most stringent constraints to date on quiescent radio emission from black hole X-ray binaries. The uncertainties in the source distances, quiescent X-ray luminosities at the times of the observations, and the power-law index of the empirical correlation between radio and X-ray luminosities make it impossible to determine whether these three sources are significantly less luminous in the radio band than expected. Thus it is not clear whether that correlation holds all the way down to quiescence for all black hole X-ray binaries.

  17. An ALMA Survey of Submillimeter Galaxies in the Extended Chandra Deep Field South: Spectroscopic Redshifts

    NASA Astrophysics Data System (ADS)

    Danielson, A. L. R.; Swinbank, A. M.; Smail, Ian; Simpson, J. M.; Casey, C. M.; Chapman, S. C.; da Cunha, E.; Hodge, J. A.; Walter, F.; Wardlow, J. L.; Alexander, D. M.; Brandt, W. N.; de Breuck, C.; Coppin, K. E. K.; Dannerbauer, H.; Dickinson, M.; Edge, A. C.; Gawiser, E.; Ivison, R. J.; Karim, A.; Kovacs, A.; Lutz, D.; Menten, K.; Schinnerer, E.; Weiß, A.; van der Werf, P.

    2017-05-01

    We present spectroscopic redshifts of {\\text{}}{S}870μ {{m}} ≳ 2 mJy submillimeter galaxies (SMGs), which have been identified from the ALMA follow-up observations of 870 μm detected sources in the Extended Chandra Deep Field South (the ALMA-LESS survey). We derive spectroscopic redshifts for 52 SMGs, with a median of z = 2.4 ± 0.1. However, the distribution features a high-redshift tail, with ˜23% of the SMGs at z≥slant 3. Spectral diagnostics suggest that the SMGs are young starbursts, and the velocity offsets between the nebular emission and UV ISM absorption lines suggest that many are driving winds, with velocity offsets of up to 2000 km s-1. Using the spectroscopic redshifts and the extensive UV-to-radio photometry in this field, we produce optimized spectral energy distributions (SEDs) using Magphys, and use the SEDs to infer a median stellar mass of {M}\\star = (6 ± 1)× 1010 M {}⊙ for our SMGs with spectroscopic redshift. By combining these stellar masses with the star formation rates (measured from the far-infrared SEDs), we show that SMGs (on average) lie a factor of ˜5 above the so-called “main sequence” at z˜ 2. We provide this library of 52 template fits with robust and uniquely well-sampled SEDs as a resource for future studies of SMGs, and also release the spectroscopic catalog of ˜2000 (mostly infrared-selected) galaxies targeted as part of the spectroscopic campaign.

  18. A sub-millimetre survey of dust enshrouded galaxies in the Hubble Deep Field North region

    NASA Astrophysics Data System (ADS)

    Borys, C. J.

    2002-12-01

    This thesis investigates the emission of sub-millimetre-wave radiation from galaxies in the Hubble Deep Field North region. The data were obtained from dedicated observing runs from our group and others using the SCUBA camera on the James Clerk Maxwell Telescope. The data were combined using techniques specifically developed here for low signal-to-noise source recovery. The sources found represent over 10% of all cosmological sources SCUBA has detected since it was commissioned. The number of sub-mm galaxies we detect account for a significant fraction of the sub-mm background, and we show that mild extrapolations can reproduce it entirely. We comment on their clustering properties, both with themselves and other high-redshift galaxy types. A multi-wavelength analysis of these galaxies shows that SCUBA sources do not all have similar properties, and are made of a collection including: star-forming radio galaxies; optically invisible objects; active galactic nuclei; and extremely red objects. Reasonable attempts to determine the redshift distribution of the sample show that SCUBA galaxies have a median redshift of around 2, and suggest that the global star formation rate may be dominated by such objects at redshifts beyond about 1. The thesis summarises the current state of extra-galactic sub-mm astronomy, and comments on how new surveys and detectors will allow us to place stronger constraints on the evolution properties of the high-redshift Universe. The research described here was made possible from grants by the Natural Science and Engineering Research Council of Canada, and a generous scholarship from the University of British Columbia.

  19. Bright z ~ 3 Lyman break galaxies in deep wide field surveys

    NASA Astrophysics Data System (ADS)

    Bian, Fuyan

    In my thesis I investigate the luminous z ˜ 3 Lyman break galaxies in deep wide field surveys. In the first part of the thesis, I use the LBT/LUCIFER to observe a lensed high-redshift star-forming galaxy (J0900+2234) at z = 2.03. With the high S/N near-IR spectroscopic observations, I reveal the detailed physical properties of this high-redshift galaxy, including SFR, metallicity, dust extinction, dynamical mass, and electron number density. In the second part of the thesis, I select a large sample of LBGs at z ˜ 3 from our new LBT Bootes field survey, and study the bright end luminosity function (LF), stellar mass function (SMF) and clustering properties of bright LBGs (1L* < L < 2.5L*). Together with other LF and SMF measurements, the evolution of LF and SMF can be well described by continuously rising star formation history model. Using the clustering measurements in this work and other works, a tight relation between the average host galaxy halo mass and the galaxy star formation rate is found, which can be interpreted as arising from cold flow accretion. The relation also suggests that the cosmic star formation efficiency is about 5%-20% of the total cold flow mass. This cosmic star formation efficiency does not evolve with redshift (from z ˜ 5 to z ˜ 3), hosting dark matter halo mass (1011 -- 1013 M⊙ ), or galaxy luminosity (from 0.3L* to 3L* ). In the third and fourth parts, with the spectroscopic follow-up observations of the bright LBGs, I establish a sample of spectroscopically-confirmed ultraluminous LBGs (ULBGs) in NOAO Boo¨tes field. With this new ULBG sample, the rest-frame UV LF of LBG at M1700A = -23.0 was measured for the first time. I find that the ULBGs have larger outflow velocity, broader Lyalpha emission and ISM absorption line profiles, and more prominent C IV P-Cygni profile. This profile may imply a top-heavy IMF in these ULBGs. The ULBGs have larger stellar mass and SFR, but smaller dust extinction than the typical L* LBGs at z ˜ 2

  20. Conducting health survey research in a deep rural South African community: challenges and adaptive strategies

    PubMed Central

    2013-01-01

    Background In many parts of the developing world, rural health requires focused policy attention, informed by reliable, representative health data. Yet there is surprisingly little published material to guide health researchers who face the unique set of hurdles associated with conducting field research in remote rural areas. Methods In this paper we provide a detailed description of the key challenges encountered during health survey field research carried out in 2010 in a deep rural site in KwaZulu-Natal, South Africa. The aim of the field research was to collect data on the health of children aged 10 to 17 years old, and their primary adult caregivers, as part of a larger national health survey; the research was a collaboration between several South African and foreign universities, South African national government departments, and various NGO partners. In presenting each of the four fieldwork challenges encountered on this site, we describe the initial planning decisions made, the difficulties faced when implementing these in the field, and the adaptive strategies we used to respond to these challenges. We reflect on learnings of potential relevance for the research community. Results Our four key fieldwork challenges were scarce research capacity, staff relocation tensions, logistical constraints, and difficulties related to community buy-in. Addressing each of these obstacles required timely assessment of the situation and adaptation of field plans, in collaboration with our local NGO partner. Adaptive strategies included a greater use of local knowledge; the adoption of tribal authority boundaries as the smallest geopolitical units for sampling; a creative developmental approach to capacity building; and planned, on-going engagement with multiple community representatives. Conclusions We argue that in order to maintain high scientific standards of research and manage to ‘get the job done’ on the ground, it is necessary to respond to fieldwork challenges

  1. The VIMOS-VLT Deep Survey: evolution in the halo occupation number since z ~ 1

    NASA Astrophysics Data System (ADS)

    Abbas, U.; de la Torre, S.; Le Fèvre, O.; Guzzo, L.; Marinoni, C.; Meneux, B.; Pollo, A.; Zamorani, G.; Bottini, D.; Garilli, B.; Le Brun, V.; Maccagni, D.; Scaramella, R.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Ilbert, O.; Iovino, A.; Lamareille, F.; McCracken, H. J.; Marano, B.; Mazure, A.; Merighi, R.; Paltani, S.; Pellò, R.; Pozzetti, L.; Radovich, M.; Vergani, D.; Zucca, E.; Bondi, M.; Bongiorno, A.; Brinchmann, J.; Cucciati, O.; de Ravel, L.; Gregorini, L.; Perez-Montero, E.; Mellier, Y.; Merluzzi, P.

    2010-08-01

    We model the evolution of the mean galaxy occupation of dark matter haloes over the range 0.1 < z < 1.3, using the data from the VIMOS-VLT Deep Survey. The galaxy projected correlation function wp(rp) was computed for a set of luminosity-limited subsamples and fits to its shape were obtained using two variants of halo occupation distribution (HOD) models. These provide us with a set of best-fitting parameters, from which we obtain the average mass of a halo and average number of galaxies per halo. We find that after accounting for the evolution in luminosity and assuming that we are largely following the same population, the underlying dark matter halo shows a growth in mass with decreasing redshift as expected in a hierarchical structure formation scenario. Using two different HOD models, we see that the halo mass grows by 90 per cent over the redshift interval z = [0.5, 1.0]. This is the first time the evolution in halo mass at high redshifts has been obtained from a single data survey and it follows the simple form seen in N-body simulations with M(z) = M0 e-βz, and β = 1.3 +/- 0.30. This provides evidence for a rapid accretion phase of massive haloes having a present-day mass M0 ~ 1013.5 h-1 Msolar, with a m > 0.1 M0 merger event occurring between redshifts of 0.5 and 1.0. Furthermore, we find that more luminous galaxies are found to occupy more massive haloes irrespective of the redshift. Finally, the average number of galaxies per halo shows little increase from redshift z ~ 1.0 to ~0.5, with a sharp increase by a factor of ~3 from z ~ 0.5 to ~0.1, likely due to the dynamical friction of subhaloes within their host haloes. Based on data obtained with the European Southern Observatory Very Large Telescope, Paranal, Chile, program 070.A-9007(A), and on data obtained at the Canada-France-Hawaii Telescope, operated by the CNRS of France, CNRC in Canada and the University of Hawaii. E-mail: abbas@oato.inaf.it

  2. JAMSTEC multibeam surveys and submersible dives around the Hawaiian Islands: a collaborative Japan-USA exploration of Hawaii's deep seafloor

    USGS Publications Warehouse

    Robinson, Joel E.; Eakins, Barry W.; Kanamatsu, Toshiya; Naka, Jiro; Takahashi, Eiichi; Satake, Kenji; Smith, John R.; Clague, David A.; Yokose, Hisayoshi

    2006-01-01

    This database release, USGS Data Series 171, contains data collected during four Japan-USA collaborative cruises that characterize the seafloor around the Hawaiian Islands. The Japan Agency for Marine-Earth Science and Technology (JAMSTEC) sponsored cruises in 1998, 1999, 2001, and 2002, to build a greater understanding of the deep marine geology around the Hawaiian Islands. During these cruises, scientists surveyed over 600,000 square kilometers of the seafloor with a hull-mounted multibeam seafloor-mapping sonar system (SEA BEAM® 2112), observed the seafloor and collected samples using robotic and manned submersible dives, collected dredge and piston-core samples, and performed single-channel seismic surveys.

  3. The VIMOS VLT Deep Survey: Final Public Release of ~ 35 000 Galaxies and Active Galactic Nuclei Covering 13 Billion Years of Evolution

    NASA Astrophysics Data System (ADS)

    Le Fèvre, O.; Adami, C.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Bondi, M.; Bongiorno, A.; Bottini, D.; Cappi, A.; Cassata, P.; Charlot, S.; Ciliegi, P.; Contini, T.; Cucciati, O.; de la Torre, S.; Foucaud, S.; Franzetti, P.; Garilli, B.; Gavignaud, I.; Guzzo, L.; Ilbert, O.; Iovino, A.; Le Brun, V.; Lemaux, B.; López-Sanjuan, C.; Maccagni, D.; McCracken, H. J.; Marano, B.; Marinoni, C.; Mazure, A.; Mellier, Y.; Merighi, R.; Merluzzi, P.; Moreau, C.; Paltani, S.; Pellò, R.; Pollo, A.; Pozzetti, L.; Scaramella, R.; Scodeggio, M.; Tasca, L.; Tresse, L.; Vergani, D.; Vettolani, G.; Zamorani, G.; Zanichelli, A.; Zucca, E.

    2014-03-01

    The VIMOS VLT Deep Survey (VVDS) final and public data release offers an excellent opportunity to revisit galaxy evolution with a sample of 35 016 galaxies and active galactic nuclei covering the redshift range 0 < z < 6.7. The VVDS includes three tiered surveys, the wide, deep and ultra-deep surveys, covering up to 8.7 square degrees, and each magnitude-selected with limits iAB = 22.5, 24 and 24.75 respectively. The VVDS redshifts, spectra, and all associated multi-wavelength data are available at http://cesam.lam.fr/vvds. The highlights and scientific legacy of the VVDS are summarised.

  4. Ultra-deep K S-band Imaging of the Hubble Frontier Fields

    NASA Astrophysics Data System (ADS)

    Brammer, Gabriel B.; Marchesini, Danilo; Labbé, Ivo; Spitler, Lee; Lange-Vagle, Daniel; Barker, Elizbeth A.; Tanaka, Masayuki; Fontana, Adriano; Galametz, Audrey; Ferré-Mateu, Anna; Kodama, Tadayuki; Lundgren, Britt; Martis, Nicholas; Muzzin, Adam; Stefanon, Mauro; Toft, Sune; van der Wel, Arjen; Vulcani, Benedetta; Whitaker, Katherine E.

    2016-09-01

    We present an overview of the “KIFF” project, which provides ultra-deep K s -band imaging of all six of the Hubble Frontier Fields clusters, Abell 2744, MACS-0416, Abell S1063, Abell 370, MACS-0717, and MACS-1149. All of these fields have recently been observed with large allocations of Directors’ Discretionary Time with the Hubble and Spitzer telescopes, covering 0.4\\lt λ \\lt 1.6 μ {{m}} and 3.6-4.5 μ {{m}}, respectively. VLT/HAWK-I integrations of the first four fields reach 5σ limiting depths of {K}s˜ 26.0 (AB, point sources) and have excellent image quality (FWHM ˜ 0.″4). The MACS-0717 and MACS-1149 fields are observable from the northern hemisphere, and shorter Keck/MOSFIRE integrations on those fields reach limiting depths of K s = 25.5 and 25.1, with a seeing FWHM of ˜ 0.″4 and 0\\buildrel{\\prime\\prime}\\over{.} 5. In all cases the K s -band mosaics cover the primary cluster and parallel HST/ACS+WFC3 fields. The total area of the K s -band coverage is 490 arcmin2. The K s -band at 2.2 μ {{m}} crucially fills the gap between the reddest HST filter (1.6 μ {{m}} ˜ H band) and the IRAC 3.6 μ {{m}} passband. While reaching the full depths of the space-based imaging is not currently feasible from the ground, the deep K s -band images provide important constraints on both the redshifts and the stellar population properties of galaxies extending well below the characteristic stellar mass across most of the age of the universe, down to and including the redshifts of the targeted galaxy clusters (z≲ 0.5). Reduced, aligned mosaics of all six survey fields are provided.

  5. AKARI North Ecliptic Pole Deep Survey. Revision of the catalogue via a new image analysis

    NASA Astrophysics Data System (ADS)

    Murata, K.; Matsuhara, H.; Wada, T.; Arimatsu, K.; Oi, N.; Takagi, T.; Oyabu, S.; Goto, T.; Ohyama, Y.; Malkan, M.; Pearson, C.; Małek, K.; Solarz, A.

    2013-11-01

    Context. We present the revised near- to mid-infrared catalogue of the AKARI North Ecliptic Pole deep survey. The survey has the unique advantage of continuous filter coverage from 2 to 24 μm over nine photometric bands, but the initial version of the survey catalogue leaves room for improvement in the image analysis stage; the original images are strongly contaminated by the behaviour of the detector and the optical system. Aims: The purpose of this study is to devise new image analysis methods and to improve the detection limit and reliability of the source extraction. Methods: We removed the scattered light and stray light from the Earth limb, and corrected for artificial patterns in the images by creating appropriate templates. We also removed any artificial sources due to bright sources by using their properties or masked them out visually. In addition, for the mid-infrared source extraction, we created detection images by stacking all six bands. This reduced the sky noise and enabled us to detect fainter sources more reliably. For the near-infrared source catalogue, we considered only objects with counterparts from ground-based catalogues to avoid fake sources. For our ground-based catalogues, we used catalogues based on the CFHT/MegaCam z' band, CFHT/WIRCam Ks band and Subaru/Scam z' band. Objects with multiple counterparts were all listed in the catalogue with a merged flag for the AKARI flux. Results: The detection limits of all mid-infrared bands were improved by ~20%, and the total number of detected objects was increased by ~2000 compared with the previous version of the catalogue; it now has 9560 objects. The 5σ detection limits in our catalogue are 11, 9, 10, 30, 34, 57, 87, 93, and 256 μJy in the N2, N3, N4, S7, S9W, S11, L15, L18W, and L24 bands, respectively. The astrometric accuracies of these band detections are 0.48, 0.52, 0.55, 0.99, 0.95, 1.1, 1.2, 1.3, and 1.6 arcsec, respectively. The false-detection rate of all nine bands was decreased

  6. A deep survey for transiting hot planets in the open cluster M37 with the MMT

    NASA Astrophysics Data System (ADS)

    Hartman, Joel David

    This thesis presents the results of a deep (14.5 [Special characters omitted.] the intermediate age open cluster M37 (NGC 2099) using the 6.5m MMT. We combine spectroscopic and photometric observations of the cluster to refine estimates of the cluster fundamental parameters, identify variable stars, study stellar rotation, and place limits on the fraction of stars with planets as small as Neptune. We determine new estimates of the fundamental cluster parameters: t 550 ± 30 Myr, E ( B - V ) = 0.227 ± 0.038, ( m - M ) v = 11.57 ± 0.13 and [ M/ H ] = +0.045 ± 0.044. We obtain light curves for ~ 23,000 stars and identify 1445 variable stars, 99% of which are new discoveries. These variables include 575 rotational variables that are potential cluster members. Using this rich sample we investigate a number of relations between rotation period, color and the amplitude of photometric variability, and we combine these results with published observations of other open clusters to test the standard theory of lower-main sequence stellar angular momentum evolution. Notably we find that the period of the Sun and the periods of solar mass stars in M37, and the Hyades do not follow the "Skumanich law", i.e. they cannot be related by a simple model invoking solid-body rotation with a standard wind angular momentum-loss law. Finally, we do not detect any transiting planets among the ~ 1450 observed cluster members. We do, however, identify a ~ 1 R J candidate planet transiting a Galactic field star. We use this null result to place 95% confidence upper limits on the fraction of cluster members and field stars with planets as a function of planetary radius and orbital period. We find that < 25% of cluster members have 0.35 R J planets with periods shorter than 1 day, and < 16% of field stars have 0.3 R J planets with periods shorter than 1 day. This is the first transit survey to place limits on the fraction of stars with planets as small as Neptune.

  7. De-blending deep Herschel surveys: A multi-wavelength approach

    NASA Astrophysics Data System (ADS)

    Pearson, W. J.; Wang, L.; van der Tak, F. F. S.; Hurley, P. D.; Burgarella, D.; Oliver, S. J.

    2017-07-01

    Aims: Cosmological surveys in the far-infrared are known to suffer from confusion. The Bayesian de-blending tool, XID+, currently provides one of the best ways to de-confuse deep Herschel SPIRE images, using a flat flux density prior. This work is to demonstrate that existing multi-wavelength data sets can be exploited to improve XID+ by providing an informed prior, resulting in more accurate and precise extracted flux densities. Methods: Photometric data for galaxies in the COSMOS field were used to constrain spectral energy distributions (SEDs) using the fitting tool CIGALE. These SEDs were used to create Gaussian prior estimates in the SPIRE bands for XID+. The multi-wavelength photometry and the extracted SPIRE flux densities were run through CIGALE again to allow us to compare the performance of the two priors. Inferred ALMA flux densities (FinferALMA), at 870 μm and 1250 μm, from the best fitting SEDs from the second CIGALE run were compared with measured ALMA flux densities (FmeasALMA) as an independent performance validation. Similar validations were conducted with the SED modelling and fitting tool MAGPHYS and modified black-body functions to test for model dependency. Results: We demonstrate a clear improvement in agreement between the flux densities extracted with XID+ and existing data at other wavelengths when using the new informed Gaussian prior over the original uninformed prior. The residuals between FmeasALMA and FinferALMA were calculated. For the Gaussian priors these residuals, expressed as a multiple of the ALMA error (σ), have a smaller standard deviation, 7.95σ for the Gaussian prior compared to 12.21σ for the flat prior; reduced mean, 1.83σ compared to 3.44σ; and have reduced skew to positive values, 7.97 compared to 11.50. These results were determined to not be significantly model dependent. This results in statistically more reliable SPIRE flux densities and hence statistically more reliable infrared luminosity estimates. Herschel

  8. The deep OB star population in Carina from the VST Photometric Hα Survey (VPHAS+)

    NASA Astrophysics Data System (ADS)

    Mohr-Smith, M.; Drew, J. E.; Napiwotzki, R.; Simón-Díaz, S.; Wright, N. J.; Barentsen, G.; Eislöffel, J.; Farnhill, H. J.; Greimel, R.; Monguió, M.; Kalari, V.; Parker, Q. A.; Vink, J. S.

    2017-02-01

    Massive OB stars are critical to the ecology of galaxies and yet our knowledge of OB stars in the Milky Way, fainter than V ∼ 12, remains patchy. Data from the VST Photometric Hα Survey (VPHAS+) permit the construction of the first deep catalogues of blue excess-selected OB stars, without neglecting the stellar field. A total of 14 900 candidates with 2MASS cross-matches are blue-selected from a 42 deg2 region in the Galactic plane, capturing the Carina Arm over the Galactic longitude range 282° ≲ ℓ ≲ 293°. Spectral energy distribution fitting is performed on these candidates' combined VPHAS+ u, g, r, i and 2MASS J, H, K magnitudes. This delivers effective temperature constraints, statistically separating O from early-B stars and high-quality extinction parameters, A0 and RV (random errors typically ∼0.1). The high-confidence O-B2 candidates number 5915 and a further 5170 fit to later B spectral type. Spectroscopy of 276 of the former confirms 97 per cent of them. The fraction of emission-line stars among all candidate B stars is 7-8 per cent. Greyer (RV > 3.5) extinction laws are ubiquitous in the region, over the distance range 2.5-3 to ∼10 kpc. Near prominent massive clusters, RV tends to rise, with particularly large and chaotic excursions to RV ∼ 5 seen in the Carina Nebula. The data reveal a hitherto unnoticed association of 108 O-B2 stars around the O5If+ star LSS 2063 (ℓ = 289.77°, b = -1.22°). Treating the OB star scaleheight as a constant within the thin disc, we find an orderly mean relation between extinction (A0) and distance in the Galactic longitude range, 287.6° < ℓ < 293.5°, and infer the subtle onset of thin-disc warping. A halo around NGC 3603, roughly a degree in diameter, of ∼500 O-B2 stars with 4 < A0(mag) < 7 is noted.

  9. THE TAIWAN ECDFS NEAR-INFRARED SURVEY: ULTRA-DEEP J AND K{sub S} IMAGING IN THE EXTENDED CHANDRA DEEP FIELD-SOUTH

    SciTech Connect

    Hsieh, Bau-Ching; Wang, Wei-Hao; Hsieh, Chih-Chiang; Lin, Lihwai; Lim, Jeremy; Ho, Paul T. P.; Yan Haojing

    2012-12-15

    We present ultra-deep J and K{sub S} imaging observations covering a 30' Multiplication-Sign 30' area of the Extended Chandra Deep Field-South (ECDFS) carried out by our Taiwan ECDFS Near-Infrared Survey (TENIS). The median 5{sigma} limiting magnitudes for all detected objects in the ECDFS reach 24.5 and 23.9 mag (AB) for J and K{sub S} , respectively. In the inner 400 arcmin{sup 2} region where the sensitivity is more uniform, objects as faint as 25.6 and 25.0 mag are detected at 5{sigma}. Thus, this is by far the deepest J and K{sub S} data sets available for the ECDFS. To combine TENIS with the Spitzer IRAC data for obtaining better spectral energy distributions of high-redshift objects, we developed a novel deconvolution technique (IRACLEAN) to accurately estimate the IRAC fluxes. IRACLEAN can minimize the effect of blending in the IRAC images caused by the large point-spread functions and reduce the confusion noise. We applied IRACLEAN to the images from the Spitzer IRAC/MUSYC Public Legacy in the ECDFS survey (SIMPLE) and generated a J+K{sub S} -selected multi-wavelength catalog including the photometry of both the TENIS near-infrared and the SIMPLE IRAC data. We publicly release the data products derived from this work, including the J and K{sub S} images and the J+K{sub S} -selected multi-wavelength catalog.

  10. Worldwide estimates of deep natural gas resources based on the U.S. Geological Survey World Petroleum Assessment 2000

    USGS Publications Warehouse

    Dyman, T.S.; Crovelli, R.A.; Bartberger, C.E.; Takahashi, K.I.

    2002-01-01

    The U.S. Geological Survey recently assessed undiscovered conventional gas and oil resources in eight regions of the world outside the U.S. The resources assessed were those estimated to have the potential to be added to reserves within the next thirty years. This study is a worldwide analysis of the estimated volumes and distribution of deep (>4.5 km or about 15,000 ft), undiscovered conventional natural gas resources based on this assessment. Two hundred forty-six assessment units in 128 priority geologic provinces, 96 countries, and two jointly held areas were assessed using a probabilistic Total Petroleum System approach. Priority geologic provinces were selected from a ranking of 937 provinces worldwide. The U.S. Geological Survey World Petroleum Assessment Team did not assess undiscovered petroleum resources in the U.S. For this report, mean estimated volumes of deep conventional undiscovered gas resources in the U.S. are taken from estimates of 101 deep plays (out of a total of 550 conventional plays in the U.S.) from the U.S. Geological Survey's 1995 National Assessment of Oil and Gas Resources. A probabilistic method was designed to subdivide gas resources into depth slices using a median-based triangular probability distribution as a model for drilling depth to estimate the percentages of estimated gas resources below various depths. For both the World Petroleum Assessment 2000 and the 1995 National Assessment of Oil and Gas Resources, minimum, median, and maximum depths were assigned to each assessment unit and play; these depths were used in our analysis. Two-hundred seventy-four deep assessment units and plays in 124 petroleum provinces were identified for the U.S. and the world. These assessment units and plays contain a mean undiscovered conventional gas resource of 844 trillion cubic ft (Tcf) occuring at depths below 4.5 km. The deep undiscovered conventional gas resource (844 Tcf) is about 17% of the total world gas resource (4,928 Tcf) based on

  11. South China Sea Tectonics and Magnetics: Constraints from IODP Expedition 349 and Deep-tow Magnetic Surveys

    NASA Astrophysics Data System (ADS)

    Lin, J.; Li, C. F.; Kulhanek, D. K.; Zhao, X.; Liu, Q.; Xu, X.; Sun, Z.; Zhu, J.

    2014-12-01

    The South China Sea (SCS) is the largest low-latitude marginal sea in the world. Its formation and evolution are linked to the complex continental-oceanic tectonic interaction of the Eurasian, Pacific, and Indo-Australian plates. Despite its relatively small size and short history, the SCS has undergone nearly a complete Wilson cycle from continental break-up to seafloor spreading to subduction. In January-March 2014, Expedition 349 of the International Ocean Discovery Program (IODP) drilled five sites in the deep basin of the SCS. Three sites (U1431, U1433, and U1434) cored into oceanic basement near the fossil spreading center on the East and Southwest Subbasins, whereas Sites U1432 and U1435 are located near the northern continent/ocean boundary of the East Subbasin. Shipboard biostratigraphy based on microfossils preserved in sediment directly above or within basement suggests that the preliminary cessation age of spreading in both the East and Southwest Subbasins is around early Miocene (16-20 Ma); however, post-cruise radiometric dating is being conducted to directly date the basement basalt in these subbasins. Prior to the IODP drilling, high-resolution near-seafloor magnetic surveys were conducted in 2012 and 2013 in the SCS with survey lines passing near the five IODP drilling sites. The deep-tow surveys revealed detailed patterns of the SCS magnetic anomalies with amplitude and spatial resolutions several times better than that of traditional sea surface measurements. Preliminary results reveal several episodes of magnetic reversal events that were not recognized by sea surface measurements. Together the IODP drilling and deep-tow magnetic surveys provide critical constraints for investigating the processes of seafloor spreading in the SCS and evolution of a mid-ocean ridge from active spreading to termination.

  12. De-biased populations of Kuiper belt objects from the deep ecliptic survey

    SciTech Connect

    Adams, E. R.; Benecchi, S. D.; Gulbis, A. A. S.; Elliot, J. L.; Buie, M. W.; Trilling, D. E.; Wasserman, L. H.

    2014-09-01

    The Deep Ecliptic Survey (DES) was a survey project that discovered hundreds of Kuiper Belt objects from 1998 to 2005. Extensive follow-up observations of these bodies has yielded 304 objects with well-determined orbits and dynamical classifications into one of several categories: Classical, Scattered, Centaur, or 16 mean-motion resonances with Neptune. The DES search fields are well documented, enabling us to calculate the probability on each frame of detecting an object with its particular orbital parameters and absolute magnitude at a randomized point in its orbit. The detection probabilities range from a maximum of 0.32 for the 3:2 resonant object 2002 GF {sub 32} to a minimum of 1.5 × 10{sup –7} for the faint Scattered object 2001 FU {sub 185}. By grouping individual objects together by dynamical classes, we can estimate the distributions of four parameters that define each class: semimajor axis, eccentricity, inclination, and object size. The orbital element distributions (a, e, and i) were fit to the largest three classes (Classical, 3:2, and Scattered) using a maximum likelihood fit. Using the absolute magnitude (H magnitude) as a proxy for the object size, we fit a power law to the number of objects versus H magnitude for eight classes with at least five detected members (246 objects). The Classical objects are best fit with a power-law slope of α = 1.02 ± 0.01 (observed from 5 ≤ H ≤ 7.2). Six other dynamical classes (Scattered plus five resonances) have consistent magnitude distribution slopes with the Classicals, provided that the absolute number of objects is scaled. Scattered objects are somewhat more numerous than Classical objects, while there are only a quarter as many 3:2 objects as Classicals. The exception to the power law relation is the Centaurs, which are non-resonant objects with perihelia closer than Neptune and therefore brighter and detectable at smaller sizes. Centaurs were observed from 7.5 < H < 11, and that population is best

  13. Overview of North Ecliptic Pole Deep Multi-wavelength Survey as a Probe of the Cosmic Noon Era

    NASA Astrophysics Data System (ADS)

    Matsuhara, Hideo; Oi, Nagisa

    2015-08-01

    An overview of the North Ecliptic Pole deep (0.5 deg2, NEP-Deep) multi-wavelength survey covering from X-ray to radio-wave is presented. The NEP-Deep provides us with several thousands of 15 μm or 18 μm selected sample of galaxies, which is the largest sample ever made at these wavelengths. A continuous filter coverage in the mid-infrared wavelength (7, 9, 11, 15, 18, and 24 μm) is unique and vital to diagnose the contributions from starbursts and AGNs in the galaxies out to z=2. The goal of the project is to resolve the nature of the cosmic star formation history at the cosmic noon era (e.g. z=1--2), and to find a clue to understand its decline from z=1 to present universe by utilizing the unique power of the multiwavelength survey. To achieve the goal we use a few diagnostic physical parameters unique to the NEP dataset: specific star-formation rate, dust attenuation, and obscured AGN fraction, etc.It is also noteworthy that the NEP is the legacy field thanks to its high visibility by the space observatories, such as eROSITA, Euclid, JWST, and SPICA. SPICA, the next generation large cooled space telescope is extremely powerful to study the rise and fall of the cosmic star-formation history in the universe.

  14. A Deep Multicolor Survey.III.Additional Spectroscopy and Implications for the Number Counts of Faint Quasars

    NASA Astrophysics Data System (ADS)

    Kennefick, Julia D.; Osmer, Patrick S.; Hall, Patrick B.; Green, Richard F.

    1997-12-01

    We have made spectroscopic identifications of 39 additional quasar candidates from the Deep Multicolor Survey (DMS) of Hall et al. (1996, ApJ, 462, 614). We have identified 9 new quasars with O.3<ζ<2.8 and l6.8<Β<21.6, all from the group of candidates with ultraviolet excess (UVX). No new quasars with ζ >3 were found among the observed candidates selected due to their red (B - R) and (V- R) colors. As a result, there are now 55 confirmed quasars in the survey: 42 with 0.3<ζ<2, nine with 2<ζ<3, three with 3<ζ<4, and 1 at ζ=4.3. One new quasar, DMS 0059-0055, is very bright with Β 16.8 and ζ=0.3, making its detection by our survey very unexpected. Including this new spectroscopy, the results of the DMS are converging with the predicted space densities of other surveys. In particular, we no longer find an excess of quasars with ζ<2.3 and Β<21 in the survey over predictions based on models by Koo & Kron (1988, ApJ, 325, 92). Also, the excess in the number of quasars seen at z>3 over predictions based on models by Warren et al. (1994, ApJ, 421, 412) is less than previously suggested. We also demonstrate the success of our quasar color modeling which is important in assessing the completeness of our survey.

  15. A visual survey technique for deep-water fishes: estimating anglerfish Lophius spp. abundance in closed areas.

    PubMed

    McIntyre, F D; Collie, N; Stewart, M; Scala, L; Fernandes, P G

    2013-10-01

    A visual survey technique was employed to estimate the abundance and distribution of anglerfish Lophius spp. in areas where destructive sampling methods, such as trawling, are unacceptable. To enable visual surveying at depths of over 300 m, a deep towed vehicle was developed equipped with video, lights and other sensors and was towed at speeds of up to 1·5 m s⁻¹ and altitudes of up to 10 m (from the seabed) to survey large areas of the seabed around the Rockall Bank in the north-west Atlantic Ocean. The system allowed for areas up to 125 000 m² to be surveyed, a substantial area comparable to that surveyed by demersal-trawl sampling. Lophius spp. densities ranged from 15 to 736 fish km⁻²; these are comparable to estimated Lophius spp. densities determined by trawl surveys in adjacent areas. Estimates of Lophius spp. abundance in the closed areas ranged between 99,855 and 176,887 for the time series considered (2007-2011). © 2013 The Authors. Journal of Fish Biology © 2013 The Fisheries Society of the British Isles.

  16. Deep Generative Models of Galaxy Images for the Calibration of the Next Generation of Weak Lensing Surveys

    NASA Astrophysics Data System (ADS)

    Lanusse, Francois; Ravanbakhsh, Siamak; Mandelbaum, Rachel; Schneider, Jeff; Poczos, Barnabas

    2017-01-01

    Weak gravitational lensing has long been identified as one of the most powerful probes to investigate the nature of dark energy. As such, weak lensing is at the heart of the next generation of cosmological surveys such as LSST, Euclid or WFIRST.One particularly crititcal source of systematic errors in these surveys comes from the shape measurement algorithms tasked with estimating galaxy shapes. GREAT3, the last community challenge to assess the quality of state-of-the-art shape measurement algorithms has in particular demonstrated that all current methods are biased to various degrees and, more importantly, that these biases depend on the details of the galaxy morphologies. These biases can be measured and calibrated by generating mock observations where a known lensing signal has been introduced and comparing the resulting measurements to the ground-truth. Producing these mock observations however requires input galaxy images of higher resolution and S/N than the simulated survey, which typically implies acquiring extremely expensive space-based observations.The goal of this work is to train a deep generative model on already available Hubble Space Telescope data which can then be used to sample new galaxy images conditioned on parameters such as magnitude, size or redshift and exhibiting complex morphologies. Such model can allow us to inexpensively produce large set of realistic realistic images for calibration purposes.We implement a conditional generative model based on state-of-the-art deep learning methods and fit it to deep galaxy images from the COSMOS survey. The quality of the model is assessed by computing an extensive set of galaxy morphology statistics on the generated images. Beyond simple second moment statistics such as size and ellipticity, we apply more complex statistics specifically designed to be sensitive to disturbed galaxy morphologies. We find excellent agreement between the morphologies of real and model generated galaxies.Our results

  17. The ROSAT Deep Survey. 2; Optical Identification, Photometry and Spectra of X-Ray Sources in the Lockman Field

    NASA Technical Reports Server (NTRS)

    Schmidt, M.; Hasinger, G.; Gunn, J.; Schneider, D.; Burg, R.; Giacconi, R.; Lehmann, I.; MacKenty, J.; Truemper, J.; Zamorani, G.

    1998-01-01

    The ROSAT Deep Survey includes a complete sample of 50 X-ray sources with fluxes in the 0.5 - 2 keV band larger than 5.5 x 10(exp -15)erg/sq cm/s in the Lockman field (Hasinger et al., Paper 1). We have obtained deep broad-band CCD images of the field and spectra of many optical objects near the positions of the X-ray sources. We define systematically the process leading to the optical identifications of the X-ray sources. For this purpose, we introduce five identification (ID) classes that characterize the process in each case. Among the 50 X-ray sources, we identify 39 AGNs, 3 groups of galaxies, 1 galaxy and 3 galactic stars. Four X-ray sources remain unidentified so far; two of these objects may have an unusually large ratio of X-ray to optical flux.

  18. The ROSAT Deep Survey. 2; Optical Identification, Photometry and Spectra of X-Ray Sources in the Lockman Field

    NASA Technical Reports Server (NTRS)

    Schmidt, M.; Hasinger, G.; Gunn, J.; Schneider, D.; Burg, R.; Giacconi, R.; Lehmann, I.; MacKenty, J.; Truemper, J.; Zamorani, G.

    1998-01-01

    The ROSAT Deep Survey includes a complete sample of 50 X-ray sources with fluxes in the 0.5 - 2 keV band larger than 5.5 x 10(exp -15)erg/sq cm/s in the Lockman field (Hasinger et al., Paper 1). We have obtained deep broad-band CCD images of the field and spectra of many optical objects near the positions of the X-ray sources. We define systematically the process leading to the optical identifications of the X-ray sources. For this purpose, we introduce five identification (ID) classes that characterize the process in each case. Among the 50 X-ray sources, we identify 39 AGNs, 3 groups of galaxies, 1 galaxy and 3 galactic stars. Four X-ray sources remain unidentified so far; two of these objects may have an unusually large ratio of X-ray to optical flux.

  19. Explained: Why many surveys of distant galaxies miss 90% of their targets

    NASA Astrophysics Data System (ADS)

    2010-03-01

    Astronomers have long known that in many surveys of the very distant Universe, a large fraction of the total intrinsic light was not being observed. Now, thanks to an extremely deep survey using two of the four giant 8.2-metre telescopes that make up ESO's Very Large Telescope (VLT) and a unique custom-built filter, astronomers have determined that a large fraction of galaxies whose light took 10 billion years to reach us have gone undiscovered. The survey also helped uncover some of the faintest galaxies ever found at this early stage of the Universe. Astronomers frequently use the strong, characteristic "fingerprint" of light emitted by hydrogen known as the Lyman-alpha line, to probe the amount of stars formed in the very distant Universe [1]. Yet there have long been suspicions that many distant galaxies go unnoticed in these surveys. A new VLT survey demonstrates for the first time that this is exactly what is happening. Most of the Lyman-alpha light is trapped within the galaxy that emits it, and 90% of galaxies do not show up in Lyman-alpha surveys. "Astronomers always knew they were missing some fraction of the galaxies in Lyman-alpha surveys," explains Matthew Hayes, the lead author of the paper, published this week in Nature, "but for the first time we now have a measurement. The number of missed galaxies is substantial." To figure out how much of the total luminosity was missed, Hayes and his team used the FORS camera at the VLT and a custom-built narrowband filter [2] to measure this Lyman-alpha light, following the methodology of standard Lyman-alpha surveys. Then, using the new HAWK-I camera, attached to another VLT Unit Telescope, they surveyed the same area of space for light emitted at a different wavelength, also by glowing hydrogen, and known as the H-alpha line. They specifically looked at galaxies whose light has been travelling for 10 billion years (redshift 2.2 [3]), in a well-studied area of the sky, known as the GOODS-South field. "This is

  20. A SURVEY OF z {approx} 6 QUASARS IN THE SLOAN DIGITAL SKY SURVEY DEEP STRIPE. II. DISCOVERY OF SIX QUASARS AT z {sub AB}>21

    SciTech Connect

    Jiang Linhua; Fan Xiaohui; Bian Fuyan; Annis, James; Lin Huan; Chiu, Kuenley; Jester, Sebastian; Lupton, Robert H.; Strauss, Michael A.; Richards, Gordon T.; Malanushenko, Viktor; Malanushenko, Elena; Schneider, Donald P.

    2009-07-15

    We present the discovery of six new quasars at z {approx} 6 selected from the Sloan Digital Sky Survey (SDSS) southern survey, a deep imaging survey obtained by repeatedly scanning a stripe along the celestial equator. The six quasars are about 2 mag fainter than the luminous z {approx} 6 quasars found in the SDSS main survey and 1 mag fainter than the quasars reported in Paper I. Four of them comprise a complete flux-limited sample at 21 < z {sub AB} < 21.8 over an effective area of 195 deg{sup 2}. The other two quasars are fainter than z {sub AB} = 22 and are not part of the complete sample. The quasar luminosity function at z {approx} 6 is well described as a single power law {phi}(L {sub 1450}) {proportional_to} L {sup {beta}} {sub 1450} over the luminosity range -28 < M {sub 1450} < -25. The best-fitting slope {beta} varies from -2.6 to -3.1, depending on the quasar samples used, with a statistical error of 0.3-0.4. About 40% of the quasars discovered in the SDSS southern survey have very narrow Ly{alpha} emission lines, which may indicate small black hole masses and high Eddington luminosity ratios, and therefore short black hole growth timescales for these faint quasars at early epochs.

  1. Trends in Continuous Deep Sedation until Death between 2007 and 2013: A Repeated Nationwide Survey

    PubMed Central

    Cohen, Joachim; Rietjens, Judith

    2016-01-01

    Background Continuous deep sedation until death is a highly debated medical practice, particularly regarding its potential to hasten death and its proper use in end-of-life care. A thorough analysis of important trends in this practice is needed to identify potentially problematic developments. This study aims to examine trends in the prevalence and practice characteristics of continuous deep sedation until death in Flanders, Belgium between 2007 and 2013, and to study variation on physicians’ degree of palliative training. Methods Population-based death certificate study in 2007 and 2013 in Flanders, Belgium. Reporting physicians received questionnaires about medical practices preceding the patient’s death. Patient characteristics, clinical characteristics (drugs used, duration, artificial nutrition/hydration, intention and consent), and palliative care training of attending physician were recorded. We posed the following question regarding continuous deep sedation: ‘Was the patient continuously and deeply sedated or kept in a coma until death by the use of one or more drugs’. Results After the initial rise of continuous deep sedation to 14.5% in 2007 (95%CI 13.1%-15.9%), its use decreased to 12.0% in 2013 (95%CI 10.9%-13.2%). Compared with 2007, in 2013 opioids were less often used as sole drug and the decision to use continuous deep sedation was more often preceded by patient request. Compared to non-experts, palliative care experts more often used benzodiazepines and less often opioids, withheld artificial nutrition/hydration more often and performed sedation more often after a request from or with the consent of the patient or family. Conclusion Worldwide, this study is the first to show a decrease in the prevalence of continuous deep sedation. Despite positive changes in performance and decision-making towards more compliance with due care requirements, there is still room for improvement in the use of recommended drugs and in the involvement of

  2. Trends in Continuous Deep Sedation until Death between 2007 and 2013: A Repeated Nationwide Survey.

    PubMed

    Robijn, Lenzo; Cohen, Joachim; Rietjens, Judith; Deliens, Luc; Chambaere, Kenneth

    2016-01-01

    Continuous deep sedation until death is a highly debated medical practice, particularly regarding its potential to hasten death and its proper use in end-of-life care. A thorough analysis of important trends in this practice is needed to identify potentially problematic developments. This study aims to examine trends in the prevalence and practice characteristics of continuous deep sedation until death in Flanders, Belgium between 2007 and 2013, and to study variation on physicians' degree of palliative training. Population-based death certificate study in 2007 and 2013 in Flanders, Belgium. Reporting physicians received questionnaires about medical practices preceding the patient's death. Patient characteristics, clinical characteristics (drugs used, duration, artificial nutrition/hydration, intention and consent), and palliative care training of attending physician were recorded. We posed the following question regarding continuous deep sedation: 'Was the patient continuously and deeply sedated or kept in a coma until death by the use of one or more drugs'. After the initial rise of continuous deep sedation to 14.5% in 2007 (95%CI 13.1%-15.9%), its use decreased to 12.0% in 2013 (95%CI 10.9%-13.2%). Compared with 2007, in 2013 opioids were less often used as sole drug and the decision to use continuous deep sedation was more often preceded by patient request. Compared to non-experts, palliative care experts more often used benzodiazepines and less often opioids, withheld artificial nutrition/hydration more often and performed sedation more often after a request from or with the consent of the patient or family. Worldwide, this study is the first to show a decrease in the prevalence of continuous deep sedation. Despite positive changes in performance and decision-making towards more compliance with due care requirements, there is still room for improvement in the use of recommended drugs and in the involvement of patients and relatives in the decision

  3. A deep redshift survey of field galaxies. Comments on the reality of the Butcher-Oemler effect

    NASA Technical Reports Server (NTRS)

    Koo, David C.; Kron, Richard G.

    1987-01-01

    A spectroscopic survey of over 400 field galaxies has been completed in three fields for which we have deep UBVI photographic photometry. The galaxies typically range from B=20 to 22 and possess redshifts z from 0.1 to 0.5 that are often quite spiky in distribution. Little, if any, luminosity evolution is observed up to redshifts z approx 0.5. By such redshifts, however, an unexpectedly large fraction of luminous galaxies has very blue intrinsic colors that suggest extensive star formation; in contrast, the reddest galaxies still have colors that match those of present-day ellipticals.

  4. Results of a Deep-Tow Multichannel Survey on the Bermuda Rise

    DTIC Science & Technology

    1988-11-01

    spacing) array are towed at full ocean depths [ Gholson and Fagot, 1983]. The design goal for DTAGS is to obtain high-resolution estimates of the structure...western Bermuda t; -A3 Rise, Geol. Soc. Amer Bull., Part 1, 91, 731-740, 1980. Gholson , N. H. and M. G. Fagot, A deep-towed sound source and hydrophone

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

    SciTech Connect

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

    2014-11-01

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

  6. Strategies for restoration of deep-water coral ecosystems based on a global survey of oil and gas regulations

    NASA Astrophysics Data System (ADS)

    Cordes, E. E.; Jones, D.; Levin, L. A.

    2016-02-01

    The oil and gas industry is one of the most active agents of the global industrialization of the deep sea. The wide array of impacts following the Deepwater Horizon oil spill highlighted the need for a systematic review of existing regulations both in US waters and internationally. Within different exclusive economic zones, there are a wide variety of regulations regarding the survey of deep-water areas prior to leasing and the acceptable set-back distances from vulnerable marine ecosystems once they are discovered. There are also varying mitigation strategies for accidental release of oil and gas, including active monitoring systems, temporary closings of oil and gas production, and marine protected areas. The majority of these regulations are based on previous studies of typical impacts from oil and gas drilling, rather than accidental releases. However, the probability of an accident from standard operations increases significantly with depth. The Oil & Gas working group of the Deep Ocean Stewardship Initiative is an international partnership of scientists, managers, non-governmental organizations, and industry professionals whose goal is to review existing regulations for the oil & gas industry and produce a best practices document to advise both developed and developing nations on their regulatory structure as energy development moves into deeper waters.

  7. Development of novel electromagnetic antenna for deep target marine CSEM survey

    NASA Astrophysics Data System (ADS)

    Akhtar, Majid Niaz; Yahya, Noorhana; Shafie, Afza; Nasir, Nadeem; Kashif, Muhammad; Zaid, Hasnah Mohd

    2012-09-01

    Marine controlled source electromagnetic method (MCSEM) is a new and versatile method for hydrocarbon detection. Deep sea hydrocarbon reservoir exploration is still challenging and expensive. Due to unreliability for the detection of DHIs using seismic data, new methods have been investigated. Sea bed logging (SBL) is a new technique for the detection of deep target hydrocarbon and has potential to reduce the risks of DHIs (direct hydrocarbon indicators) in deep sea environment. The magnitude of EM waves is very important for the detection of deep target hydrocarbon reservoir below 4000m from the sea floor. Nanotechnology has been introduced very effective and shows promising results in many research fields. Ferrite magnetic materials play an important role in many applications due to its versatile magnetic properties. The aluminum based EM antenna is developed and NiZn, YIG ferrite as magnetic feeders are used to increase the field strength from EM antenna. FESEM images show that grain size increases with the increase of sintering temperature and ranges from 30 to 60nm for Ni0.8Zn0.2Fe2O4 where as grain size increases from 45 to 110nm for Y3Fe5O12 samples. Due to better magnetic properties, samples (Ni0.8Zn0.2Fe2O4-PVDF) sintered at 950°C and (Y3Fe5O12-PVDF) sintered at 1350°C were used as magnetic feeders for the EM antenna. It was investigated that magnitude of EM waves from the novel EM antenna with (Ni0.8Zn0.2Fe2O4-PVDF) sintered at 950°C and Y3Fe5O12-PVDF) sintered at 1150°C increases up to 143% and 220% respectively in the lab scale environment. Modeling results by using CST software shows that new EM antenna with magnetic feeders has an ability to increase the D, E, B and H field components. This novel EM antenna with magnetic feeders may be used for the deep target hydrocarbon detection due to enhanced field strength. This new EM transmitter based on nanotechnology may open new horizons for oil and gas industry for deep target hydrocarbon reservoir.

  8. Joint US-Japan Observations with the Infrared Space Observatory (ISO): Deep Surveys and Observations of High-Z Objects

    NASA Technical Reports Server (NTRS)

    Sanders, David B.

    1997-01-01

    Several important milestones were passed during the past year of our ISO observing program: (1) Our first ISO data were successfully obtained. ISOCAM data were taken for our primary deep field target in the 'Lockman Hole'. Thirteen hours of integration (taken over 4 contiguous orbits) were obtained in the LW2 filter of a 3 ft x 3 ft region centered on the position of minimum HI column density in the Lockman Hole. The data were obtained in microscanning mode. This is the deepest integration attempted to date (by almost a factor of 4 in time) with ISOCAM. (2) The deep survey data obtained for the Lockman Hole were received by the Japanese P.I. (Yoshi Taniguchi) in early December, 1996 (following release of the improved pipeline formatted data from Vilspa), and a copy was forwarded to Hawaii shortly thereafter. These data were processed independently by the Japan and Hawaii groups during the latter part of December 1996, and early January, 1997. The Hawaii group made use of the U.S. ISO data center at IPAC/Caltech in Pasadena to carry out their data reduction, while the Japanese group used a copy of the ISOCAM data analysis package made available to them through an agreement with the head of the ISOCAM team, Catherine Cesarsky. (3) Results of our LW2 Deep Survey in the Lockman Hole were first reported at the ISO Workshop "Taking ISO to the Limits: Exploring the Faintest Sources in the Infrared" held at the ISO Science Operations Center in Villafranca, Spain (VILSPA) on 3-4 February, 1997. Yoshi Taniguchi gave an invited presentation summarizing the results of the U.S.-Japan team, and Dave Sanders gave an invited talk summarizing the results of the Workshop at the conclusion of the two day meeting. The text of the talks by Taniguchi and Sanders are included in the printed Workshop Proceedings, and are published in full on the Web. By several independent accounts, the U.S.-Japan Deep Survey results were one of the highlights of the Workshop; these data showed

  9. Seismic stability of the survey areas of potential sites for the deep geological repository of the spent nuclear fuel

    NASA Astrophysics Data System (ADS)

    Kaláb, Zdeněk; Šílený, Jan; Lednická, Markéta

    2017-07-01

    This paper deals with the seismic stability of the survey areas of potential sites for the deep geological repository of the spent nuclear fuel in the Czech Republic. The basic source of data for historical earthquakes up to 1990 was the seismic website [10]. The most intense earthquake described occurred on September 15, 1590 in the Niederroesterreich region (Austria) in the historical period; its reported intensity is Io = 8-9. The source of the contemporary seismic data for the period since 1991 to the end of 2014 was the website [11]. It may be stated based on the databases and literature review that in the period from 1900, no earthquake exceeding magnitude 5.1 originated in the territory of the Czech Republic. In order to evaluate seismicity and to assess the impact of seismic effects at depths of hypothetical deep geological repository for the next time period, the neo-deterministic method was selected as an extension of the probabilistic method. Each one out of the seven survey areas were assessed by the neo-deterministic evaluation of the seismic wave-field excited by selected individual events and determining the maximum loading. Results of seismological databases studies and neo-deterministic analysis of Čihadlo locality are presented.

  10. Multiparametrical survey to understand the dynamic of monitored deep seated Landslide (La Clapière DSL)

    NASA Astrophysics Data System (ADS)

    Palis, Edouard; Lebourg, Thomas; Vidal, Maurin; Vitard, Clement; Tric, Emmanuel

    2014-05-01

    The geology and the structure of a deep seated landslide (La Clapiere with 65 million m3, south eastern France) explains the complex hydrology of the site which plays a key-role in the destabilization and the multiphase dynamics of the slope (water circulation within the sliding mass, fluid exchanges between superficial and deep layers aquifer through faults). To understand fluid circulations within the unstable slope, a pluri-annual multi parametric survey was set up, but since 18 months the survey combines new research multiparametric station. The landslide (La Clapiere) is located in the Argentera-Mercantour massif, and it has been instrumented since 1982 by academic researchers and since 2003 by the Multidisciplinary Observatory of Versant Instabilities (OMIV, the French National Observation Service (SNO)). A permanent electrical tomography monitoring was installed on the landslide since November 2012 to complement the actual monitoring system (GPS, seismic, pluviometric and hydrogeologic data). The aim of this study is to analyze the temporal evolution of resistivity, positioning and pluviometry during the November 2012 to March 2013 period. A qualitative and statistical approach by clustering, principal component analysis (PCA), and probability density function (Pdf) of resistivity data, coupled with pluviometric and GPS data provides a better understanding of the dynamics in this place. Rainfall induces strong accelerations of the rockslide movement. This new statistical study also explained the major roles of the fault and the basement of the landslide, and the time chronology of the water flow in the massif.

  11. The GALEX VIMOS-VLT Deep Survey Measurement of the Evolution of the 1500 Å Luminosity Function

    NASA Astrophysics Data System (ADS)

    Arnouts, S.; Schiminovich, D.; Ilbert, O.; Tresse, L.; Milliard, B.; Treyer, M.; Bardelli, S.; Budavari, T.; Wyder, T. K.; Zucca, E.; Le Fèvre, O.; Martin, D. C.; Vettolani, G.; Adami, C.; Arnaboldi, M.; Barlow, T.; Bianchi, L.; Bolzonella, M.; Bottini, D.; Byun, Y.-I.; Cappi, A.; Charlot, S.; Contini, T.; Donas, J.; Forster, K.; Foucaud, S.; Franzetti, P.; Friedman, P. G.; Garilli, B.; Gavignaud, I.; Guzzo, L.; Heckman, T. M.; Hoopes, C.; Iovino, A.; Jelinsky, P.; Le Brun, V.; Lee, Y.-W.; Maccagni, D.; Madore, B. F.; Malina, R.; Marano, B.; Marinoni, C.; McCracken, H. J.; Mazure, A.; Meneux, B.; Merighi, R.; Morrissey, P.; Neff, S.; Paltani, S.; Pellò, R.; Picat, J. P.; Pollo, A.; Pozzetti, L.; Radovich, M.; Rich, R. M.; Scaramella, R.; Scodeggio, M.; Seibert, M.; Siegmund, O.; Small, T.; Szalay, A. S.; Welsh, B.; Xu, C. K.; Zamorani, G.; Zanichelli, A.

    2005-01-01

    We present the first measurement of the galaxy luminosity function (LF) at 1500 Å in the range 0.2<=z<=1.2 based on Galaxy Evolution Explorer VIMOS-VLT Deep Survey observations (~1000 spectroscopic redshifts for galaxies with NUV<=24.5) and at higher z using existing data sets. Our main results are summarized as follows: (1) Luminosity evolution is observed with ΔM*~-2.0 mag between z=0 and z=1 and ΔM*~-1.0 mag between z=1 and z=3. This confirms that the star formation activity was significantly higher in the past. (2) The LF slopes vary in the range -1.2>=α>=-1.65, with a marginally significant hint of increase at higher z. (3) We split the sample in three rest-frame (B-I) intervals, providing an approximate spectral type classification: Sb-Sd, Sd-Irr, and unobscured starbursts. We find that the bluest class evolves less strongly in luminosity than the two other classes. On the other hand, their number density increases sharply with z (~15% in the local universe to ~55% at z~1), while that of the reddest classes decreases. The VIMOS-VLT Deep Survey observations have been obtained with the European Southern Observatory Very Large Telescope, Paranal, Chile.

  12. A deep survey of the Galactic plane at very high energies

    NASA Astrophysics Data System (ADS)

    Chow, Yeuk Chun

    The Cygnus region of the Galactic plane contains many known supernova remnants, pulsars, X-Ray sources and GeV emitters which makes it a prime candidate for a Very High Energy (VHE) survey study in the Northern Hemisphere. VERITAS, an array of atmospheric Cherenkov telescopes located in southern Arizona, USA, is the most sensitive very high energy gamma-ray telescope in operation today. Between April 2007 and Fall 2009, VERITAS carried out an extensive survey of the Cygnus region between 67 and 82 degrees in Galactic longitude and between -1 and 4 degrees in Galactic latitude. The survey, comprising more than 140 hours of observations, reached an average VHE flux sensitivity of better than 5% of the Crab Nebula flux at energies above 200 GeV, making it the most sensitive VHE gamma-ray survey ever done in the northern Hemisphere. The survey data set revealed two highly probable gamma-ray sources in the region. A detailed description of the observational strategy and analysis methodology of the survey are given and a discussion of the scientific implications resulting from the survey is provided.

  13. Deep seismic survey images crustal structure of Tornquist Zone beneath southern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Meissner, R.; Sadowiak, P.; Thomas, S.; Wever, T.; Dickmann, T.; Flüh, E.; Berthelsen, A.; Thybo, H.; Dahl-Jensen, T.; Balling, N.; Nørmark, E.; Hobbs, R. W.; Klemperer, S. L.; Matthews, D. H.; Snyder, D. B.; Long, R.; Graham, D.; Matthews, T.; Blundell, D. J.; Lund, C.; Palm, H.; Pedersen, L.; Roberts, R.; Elming, S.-E.; Heikkinen, P.; Korhonen, H.; Luosto, U.; Hjelt, S.-E.; Komminaho, K.; Yliniemi, J.

    1991-06-01

    The Tornquist Zone is Europe's longest tectonic lineament and bisects the continent in a NW-SE direction from the North Sea (off NW Denmark) to the Black Sea. New deep seismic reflection and coincident refraction data have been collected across its 50 km wide, intensely faulted and inverted NW part. The marine reflection profile in the area north of Bornholm Island shows a tilted block structure in the rigid upper crust, whereas the lower crust seems to be more gently uplifted. A complex transition from the highly reflective lower crust to the mantle is indicated by mantle reflections and a curious wide-angle event recorded by a landstation on Bornholm Island. We suggest that deep-reaching inversion tectonics, induced by Alpine and Carpathian orogeny, were responsible for the development of the gross crust-mantle structure of the Tornquist Zone in our study area, which seems to be similar to that in Poland.

  14. Deep seismic survey images crustal structure of Tornquist Zone beneath southern Baltic Sea

    SciTech Connect

    Not Available

    1991-06-01

    The Tornquist Zone is Europe's longest tectonic lineament and bisects the continent in a NW-SE direction from the North Sea (off NW Denmark) to the Black Sea. New deep seismic reflection and coincident refraction data have been collected across its 50 km wide, intensely faulted and inverted NW part. The marine reflection profile in the area north of Bornholm Island shows a tilted block structure in the rigid upper crust, whereas the lower crust seems to be more gently uplifted. A complex transition from the highly reflective lower crust to the mantle is indicated by mantle reflections and a curious wide-angle event recorded by a landstation on Bornholm Island. The authors suggest that deep-reaching inversion tectonics, induced by Alpine and Carpathian orogeny, were responsible for the development of the gross crust-mantle structure of the Tornquist Zone in the study area, which seems to be similar to that in Poland.

  15. The SXDF-ALMA 2-arcmin2 Deep Survey: Stacking Rest-frame Near-infrared Selected Objects

    NASA Astrophysics Data System (ADS)

    Wang, Wei-Hao; Kohno, Kotaro; Hatsukade, Bunyo; Umehata, Hideki; Aretxaga, Itziar; Hughes, David; Caputi, Karina I.; Dunlop, James S.; Ikarashi, Soh; Iono, Daisuke; Ivison, Rob J.; Lee, Minju; Makiya, Ryu; Matsuda, Yuichi; Motohara, Kentaro; Nakanish, Kouichiro; Ohta, Kouji; Tadaki, Ken-ichi; Tamura, Yoichi; Kodama, Tadayuki; Rujopakarn, Wiphu; Wilson, Grant W.; Yamaguchi, Yuki; Yun, Min S.; Coupon, Jean; Hsieh, Bau-Ching; Foucaud, Sébastien

    2016-12-01

    We present stacking analyses on our ALMA deep 1.1 mm imaging in the Subaru/XMM-Newton Deep Survey Field using 1.6 and 3.6 μm selected galaxies in the CANDELS WFC3 catalog. We detect a stacked flux of ˜0.03-0.05 mJy, corresponding to {L}{IR}\\lt {10}11 {L}⊙ and a star formation rate (SFR) of ˜ 15 {M}⊙ yr-1 at z = 2. We find that galaxies that are brighter in the rest-frame near-infrared tend to also be brighter at 1.1 mm, and galaxies fainter than {m}3.6μ {{m}}=23 do not produce detectable 1.1 mm emission. This suggests a correlation between stellar mass and SFR, but outliers to this correlation are also observed, suggesting strongly boosted star formation or extremely large extinction. We also find tendencies that redder galaxies and galaxies at higher redshifts are brighter at 1.1 mm. Our field contains z˜ 2.5 Hα emitters and a bright single-dish source. However, we do not find evidence of bias in our results caused by the bright source. By combining the fluxes of sources detected by ALMA and fluxes of faint sources detected with stacking, we recover a 1.1 mm surface brightness of up to 20.3 ± 1.2 Jy deg-2, comparable to the extragalactic background light measured by COBE. Based on the fractions of optically faint sources in our and previous ALMA studies and the COBE measurements, we find that approximately half of the cosmic star formation may be obscured by dust and missed by deep optical surveys. Much deeper and wider ALMA imaging is therefore needed to better constrain the obscured cosmic star formation history.

  16. The DEEP2 galaxy redshift survey: the evolution of the blue fraction in groups and the field

    NASA Astrophysics Data System (ADS)

    Gerke, Brian F.; Newman, Jeffrey A.; Faber, S. M.; Cooper, Michael C.; Croton, Darren J.; Davis, Marc; Willmer, Christopher N. A.; Yan, Renbin; Coil, Alison L.; Guhathakurta, Puragra; Koo, David C.; Weiner, Benjamin J.

    2007-04-01

    We explore the behaviour of the blue galaxy fraction over the redshift range 0.75 <= z <= 1.3 in the DEEP2 Survey, both for field galaxies and for galaxies in groups. The primary aim is to determine the role that groups play in driving the evolution of galaxy colour at high z. In pursuing this aim, it is essential to define a galaxy sample that does not suffer from redshift-dependent selection effects in colour-magnitude space. We develop four such samples for this study: at all redshifts considered, each one is complete in colour-magnitude space, and the selection also accounts for evolution in the galaxy luminosity function. These samples will also be useful for future evolutionary studies in DEEP2. The colour segregation observed between local group and field samples is already in place at z ~ 1: DEEP2 groups have a significantly lower blue fraction than the field. At fixed z, there is also a correlation between blue fraction and galaxy magnitude, such that brighter galaxies are more likely to be red, both in groups and in the field. In addition, there is a negative correlation between blue fraction and group richness. In terms of evolution, the blue fraction in groups and the field remains roughly constant from z = 0.75 to 1, but beyond this redshift the blue fraction in groups rises rapidly with z, and the group and field blue fractions become indistinguishable at z ~ 1.3. Careful tests indicate that this effect does not arise from known systematic or selection effects. To further ensure the robustness of this result, we build on previous mock DEEP2 catalogues to develop mock catalogues that reproduce the colour-overdensity relation observed in DEEP2 and use these to test our methods. The convergence between the group and field blue fractions at z ~ 1.3 implies that DEEP2 galaxy groups only became efficient at quenching star formation at z ~ 2; this result is broadly consistent with other recent observations and with current models of galaxy evolution and

  17. Ectoparasitism on deep-sea fishes in the western North Atlantic: In situ observations from ROV surveys

    USGS Publications Warehouse

    Quattrini, Andrea; Demopoulos, Amanda W.J.

    2016-01-01

    A complete understanding of how parasites influence marine ecosystem functioning requires characterizing a broad range of parasite-host interactions while determining the effects of parasitism in a variety of habitats. In deep-sea fishes, the prevalence of parasitism remains poorly understood. Knowledge of ectoparasitism, in particular, is limited because collection methods often cause dislodgment of ectoparasites from their hosts. High-definition video collected during 43 remotely operated vehicle surveys (2013–2014) provided the opportunity to examine ectoparasitism on fishes across habitats (open slope, canyon, seamount, cold seep) and depths (494–4689 m) off the northeastern U.S., while providing high-resolution images and valuable observations of fish behavior. Only 9% (n = 125 individuals) of all observed fishes (25 species) were confirmed with ectoparasites, but higher percentages (∼33%) were observed for some of the most abundant fish species (e.g., Antimora rostrata). Ectoparasites included two copepod families (Lernaeopodidae, Sphyriidae) that infected four host species, two isopod families (Cymothoidae, Aegidae) that infected three host species, and one isopod family (Gnathiidae) that infected 19 host species. Hyperparasitism was also observed. As host diversity declined with depth, ectoparasite diversity declined; only gnathiids were observed at depths down to 3260 m. Thus, gnathiids appear to be the most successful group to infect a diversity of fishes across a broad depth range in the deep sea. For three dominant fishes (A. rostrata, Nezumia bairdii, Synaphobranchus spp.), the abundance and intensity of ectoparasitism peaked in different depths and habitats depending on the host species examined. Notably, gnathiid infections were most intense on A. rostrata, particularly in submarine canyons, suggesting that these habitats may increase ectoparasite infections. Although ectoparasitism is often overlooked in deep-sea benthic communities

  18. Ectoparasitism on deep-sea fishes in the western North Atlantic: In situ observations from ROV surveys.

    PubMed

    Quattrini, Andrea M; Demopoulos, Amanda W J

    2016-12-01

    A complete understanding of how parasites influence marine ecosystem functioning requires characterizing a broad range of parasite-host interactions while determining the effects of parasitism in a variety of habitats. In deep-sea fishes, the prevalence of parasitism remains poorly understood. Knowledge of ectoparasitism, in particular, is limited because collection methods often cause dislodgment of ectoparasites from their hosts. High-definition video collected during 43 remotely operated vehicle surveys (2013-2014) provided the opportunity to examine ectoparasitism on fishes across habitats (open slope, canyon, seamount, cold seep) and depths (494-4689 m) off the northeastern U.S., while providing high-resolution images and valuable observations of fish behavior. Only 9% (n = 125 individuals) of all observed fishes (25 species) were confirmed with ectoparasites, but higher percentages (∼33%) were observed for some of the most abundant fish species (e.g., Antimora rostrata). Ectoparasites included two copepod families (Lernaeopodidae, Sphyriidae) that infected four host species, two isopod families (Cymothoidae, Aegidae) that infected three host species, and one isopod family (Gnathiidae) that infected 19 host species. Hyperparasitism was also observed. As host diversity declined with depth, ectoparasite diversity declined; only gnathiids were observed at depths down to 3260 m. Thus, gnathiids appear to be the most successful group to infect a diversity of fishes across a broad depth range in the deep sea. For three dominant fishes (A. rostrata, Nezumia bairdii, Synaphobranchus spp.), the abundance and intensity of ectoparasitism peaked in different depths and habitats depending on the host species examined. Notably, gnathiid infections were most intense on A. rostrata, particularly in submarine canyons, suggesting that these habitats may increase ectoparasite infections. Although ectoparasitism is often overlooked in deep-sea benthic communities, our

  19. The SCUBA-2 Cosmology Legacy Survey: galaxies in the deep 850 μm survey, and the star-forming `main sequence'

    NASA Astrophysics Data System (ADS)

    Koprowski, M. P.; Dunlop, J. S.; Michałowski, M. J.; Roseboom, I.; Geach, J. E.; Cirasuolo, M.; Aretxaga, I.; Bowler, R. A. A.; Banerji, M.; Bourne, N.; Coppin, K. E. K.; Chapman, S.; Hughes, D. H.; Jenness, T.; McLure, R. J.; Symeonidis, M.; Werf, P. van der

    2016-06-01

    We investigate the properties of the galaxies selected from the deepest 850-μm survey undertaken to date with (Submillimetre Common-User Bolometer Array 2) SCUBA-2 on the James Clerk Maxwell Telescope as part of the SCUBA-2 Cosmology Legacy Survey. A total of 106 sources (>5σ) were uncovered at 850 μm from an area of ≃150 arcmin2 in the centre of the COSMOS/UltraVISTA/Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) field, imaged to a typical depth of σ850 ≃ 0.25 mJy. We utilize the available multifrequency data to identify galaxy counterparts for 80 of these sources (75 per cent), and to establish the complete redshift distribution for this sample, yielding bar{z} = 2.38± 0.09. We have also been able to determine the stellar masses of the majority of the galaxy identifications, enabling us to explore their location on the star formation rate:stellar mass (SFR:M*) plane. Crucially, our new deep 850-μm-selected sample reaches flux densities equivalent to SFR ≃ 100 M⊙ yr-1, enabling us to confirm that sub-mm galaxies form the high-mass end of the `main sequence' (MS) of star-forming galaxies at z > 1.5 (with a mean specific SFR of sSFR = 2.25 ± 0.19 Gyr-1 at z ≃ 2.5). Our results are consistent with no significant flattening of the MS towards high masses at these redshifts. However, our results add to the growing evidence that average sSFR rises only slowly at high redshift, resulting in log10sSFR being an apparently simple linear function of the age of the Universe.

  20. The VIMOS VLT deep survey. The K-band follow-up in the 0226-04 field

    NASA Astrophysics Data System (ADS)

    Temporin, S.; Iovino, A.; Bolzonella, M.; McCracken, H. J.; Scodeggio, M.; Garilli, B.; Bottini, D.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Picat, J. P.; Scaramella, R.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnouts, S.; Bardelli, S.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Cucciati, O.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Ilbert, O.; Marano, B.; Marinoni, C.; Mazure, A.; Meneux, B.; Merighi, R.; Paltani, S.; Pellò, R.; Pollo, A.; Pozzetti, L.; Radovich, M.; Vergani, D.; Zamorani, G.; Zucca, E.; Bondi, M.; Bongiorno, A.; Brinchmann, J.; de la Torre, S.; Lamareille, F.; Mellier, Y.; Walcher, C. J.

    2008-04-01

    We present a new K_s-band survey that represents a significant extension to the previous wide-field K_s-band imaging survey within the 0226-04 field of the VIMOS-VLT deep survey (VVDS). The new data add ~458 arcmin2 to the previous imaging program, thus allowing us to cover a total contiguous area of ~600 arcmin2 within this field. Sources were identified both directly on the final K-band mosaic image and on the corresponding, deep χ^2-g'r'i' image from the CFHT Legacy Survey in order to reduce contamination, while ensuring compilation of a truly K-selected catalogue down to the completeness limit of the K_s-band. The newly determined K_s-band magnitudes are used in combination with the ancillary multiwavelength data for determining accurate photometric redshifts. The final catalogue totals ~52 000 sources, out of which ~4400 have a spectroscopic redshift from the VVDS first epoch survey. The catalogue is 90% complete down to KVega = 20.5 mag. We present K_s-band galaxy counts and angular correlation function measurements down to this magnitude limit. Our results are in good agreement with previously published work. We show that using K magnitudes to determine photometric redshifts significantly lowers the incidence of catastrophic errors. The data presented in this paper are publicly available through the CENCOS database. Based on observations collected at the European Southern Observatory New Technology Telescope, La Silla, Chile, programme 075.A-0752(A), on data obtained with the European Southern Observatory Very Large Telescope, Paranal, Chile, programme 070.A-9007(A), and on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT), which is operated by the National Research Council (NRC) of Canada, the Institut National des Science de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products

  1. Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey -- GOODS-South Field, Non-SNe-Searched Visits

    NASA Astrophysics Data System (ADS)

    Faber, Sandra

    2011-10-01

    The Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey {CANDELS}is designed to document the ?rst third of galactic evolution from z =8 to 1.5 via deep imaging of more than 250,000 galaxies with WFC3/IRand ACS. It will also find the first Type Ia SNe beyond z > 1.5 andestablish their accuracy as standard candles for cosmology. Fivepremier multi-wavelength sky regions selected from the SpitzerExtragalactic Deep Survey {SEDS} provide complementary IRAC imagingdata down to 26.5 AB mag, a unique resource for stellar masses at allredshifts. The use of ?ve widely separated ?elds mitigates cosmicvariance and yields statistically robust and complete samples ofgalaxies down to 10^9 solar masses out to z 8.The program merges two originally separate MCT proposals. The Faberprogram incorporates a ?Wide? imaging survey in three separate fieldsto 2 orbit depth over 0.2 sq. degrees, plus a ?Deep? imaging surveyto 12 orbit depth in the two GOODS regions over 0.04 sq. degrees.When combined with ultra-deep imaging from the Hubble Ultradeep Fieldprogram {GO 11563}, the result is a three-tiered strategy that ef?cientlysamples both bright/rare and faint/common extragalactic objects. TheFerguson program adds an extensive high-redshift Type Ia SNe search,plus ultraviolet "daytime" UVIS exposures in GOODS-N to exploit theCVZ opportunity in that field.This program, GO 12064, is part of the Wide mosaic survey, which has thefollowing field centers and sizes: Field ID RA{2000} Dec{2000} WFC3 Dim. PA on sky UDS 02 17 38 -05 12 02 4x11 270 COSMOS 10 00 31 +02 24 00 4x11 180 EGS 14 19 31 +52 54 10 3x15 41 Science highlights from the Wide program: * Underlying structural properties of galaxies as revealed by WFC3-IR images sensitive to older stars {beyond the 4000-A break} and less affected by dust than ACS. A key redshift is z 2, where star-formation peaks, QSOs are most abundant, and where restframe B-band is still accessible to WFC3. Sample questions include: - Structure in young vs. old

  2. A deep Giant Metre-wave Radio Telescope 610-MHz survey of the 1H XMM-Newton/Chandra survey field

    NASA Astrophysics Data System (ADS)

    Moss, D.; Seymour, N.; McHardy, I. M.; Dwelly, T.; Page, M. J.; Loaring, N. S.

    2007-07-01

    We present the results of a deep 610-MHz survey of the 1H XMM-Newton/Chandra survey area with the Giant Metre-wave Radio Telescope. The resulting maps have a resolution of ~7 arcsec and an rms noise limit of 60 μJy. To a 5σ detection limit of 300 μJy, we detect 223 sources within a survey area of 64 arcmin in diameter. We compute the 610-MHz source counts and compare them to those measured at other radio wavelengths. The well-known flattening of the Euclidean-normalized 1.4-GHz source counts below ~2 mJy, usually explained by a population of starburst galaxies undergoing luminosity evolution, is seen at 610 MHz. The 610-MHz source counts can be modelled by the same populations that explain the 1.4-GHz source counts, assuming a spectral index of -0.7 for the starburst galaxies and the steep spectrum active galactic nucleus (AGN) population. We find a similar dependence of luminosity evolution on redshift for the starburst galaxies at 610 MHz as is found at 1.4 GHz (i.e. `Q' = 2.45+0.3-0.4).

  3. Study of Conrad and Shaban deep brines, Red Sea, using bathymetric, parasound and seismic surveys

    NASA Astrophysics Data System (ADS)

    Salem, Mohamed

    2017-06-01

    Red Sea was formed where African and Arabian plates are moving apart. Each year the plates drift about 2.5 cm farther apart, so that the Red Sea is slowly but steadily growing hence known as the next coming ocean simply an embryonic ocean. It is characterized by the presence of many deep fractures, located almost exactly along the middle of the Sea from northwest to southeast. Theses fractures have steep sides, rough bottom and brines coming up form on the bottom. Brine deposits are the result of subsurface magmatic activity. They are formed in graben structure as shown by the bathymetric, parasound and seismic studies in the investigated area.

  4. Survey of methods used to determine if a patient has a deep vein thrombosis: An exploratory research report.

    PubMed

    Heick, John D; Farris, James W

    2017-09-01

    The use of evidence-based practice (EBP) is encouraged in the physical therapy profession, but integrating evidence into practice can be difficult for clinicians because of lack of time and other constraints. To survey physical therapy clinical instructors and determine the methods they use for screening for deep vein thrombosis (DVT), a type of venous thromboembolism (VTE) in the lower extremities. Exploratory survey. Twelve survey questions written specifically for this study were sent to a convenience sample of clinical instructors associated with seven universities across 43 states. Eight hundred fifty clinical instructors (22.4% response rate) completed the survey. Of those who responded, 80.5% were taught to use Homans sign to screen for a possible DVT in their entry-level education and 67.9% continued to use Homans sign in clinical practice. Regardless of post-graduate education, respondents were more likely to choose Homans sign than a clinical decision rule (CDR) to screen for a suspected DVT. Additionally, nearly two-thirds of respondents failed to correctly identify one or more of the major risk factors for developing a DVT/VTE. The response rate was 22.4% and therefore may not fully represent the population of physical therapy clinical instructors in the United States. Results from this exploratory survey indicated that approximately two-thirds of physical therapy clinical instructors used outdated DVT/VTE screening methods that they were taught in their entry-level education and nearly two-thirds did not identify the major risk factors associated with DVT/VTE. These results suggest that change is necessary in physical therapy education, clinical practice, and continuing professional development to ensure a more evidenced-based identification of DVT and VTE.

  5. Pathogen-specific deep sequence-coupled biopanning: A method for surveying human antibody responses

    PubMed Central

    Pascale, Juan M.; Moreno, Brechla; Chackerian, Bryce; Peabody, David S.

    2017-01-01

    Identifying the targets of antibody responses during infection is important for designing vaccines, developing diagnostic and prognostic tools, and understanding pathogenesis. We developed a novel deep sequence-coupled biopanning approach capable of identifying the protein epitopes of antibodies present in human polyclonal serum. Here, we report the adaptation of this approach for the identification of pathogen-specific epitopes recognized by antibodies elicited during acute infection. As a proof-of-principle, we applied this approach to assessing antibodies to Dengue virus (DENV). Using a panel of sera from patients with acute secondary DENV infection, we panned a DENV antigen fragment library displayed on the surface of bacteriophage MS2 virus-like particles and characterized the population of affinity-selected peptide epitopes by deep sequence analysis. Although there was considerable variation in the responses of individuals, we found several epitopes within the Envelope glycoprotein and Non-Structural Protein 1 that were commonly enriched. This report establishes a novel approach for characterizing pathogen-specific antibody responses in human sera, and has future utility in identifying novel diagnostic and vaccine targets. PMID:28152075

  6. Pathogen-specific deep sequence-coupled biopanning: A method for surveying human antibody responses.

    PubMed

    Frietze, Kathryn M; Pascale, Juan M; Moreno, Brechla; Chackerian, Bryce; Peabody, David S

    2017-01-01

    Identifying the targets of antibody responses during infection is important for designing vaccines, developing diagnostic and prognostic tools, and understanding pathogenesis. We developed a novel deep sequence-coupled biopanning approach capable of identifying the protein epitopes of antibodies present in human polyclonal serum. Here, we report the adaptation of this approach for the identification of pathogen-specific epitopes recognized by antibodies elicited during acute infection. As a proof-of-principle, we applied this approach to assessing antibodies to Dengue virus (DENV). Using a panel of sera from patients with acute secondary DENV infection, we panned a DENV antigen fragment library displayed on the surface of bacteriophage MS2 virus-like particles and characterized the population of affinity-selected peptide epitopes by deep sequence analysis. Although there was considerable variation in the responses of individuals, we found several epitopes within the Envelope glycoprotein and Non-Structural Protein 1 that were commonly enriched. This report establishes a novel approach for characterizing pathogen-specific antibody responses in human sera, and has future utility in identifying novel diagnostic and vaccine targets.

  7. Comparison of navigation in ROV and AUV surveys with high frequency acoustic systems in deep seafloor hydrothermal environments

    NASA Astrophysics Data System (ADS)

    Le Bas, T.; Murton, B. J.; Webber, A.

    2013-12-01

    As high frequency acoustic waves are highly attenuated over short distances it is essential that all high resolution surveys must be conducted close to the seafloor. In the deep ocean (over 2500m) this means that the location of a survey vehicle compared to a ship's well constrained position has some significant issues. This paper compares various methods and results of a ROV and AUV multibeam survey over the Mid Cayman Spreading Centre hydrothermal vent sites. The results show the difficulties encountered in processing when navigation uncertainty is considerably higher than the resolution of survey data. For example the best ROV positional accuracy in 5000m water depth is about 10m using USBL, whereas high-frequency multibeam systems used on ROVs and AUVs has a resolution of 50cm or better. AUV location has different navigational challenges. While the continuous movement of an AUV during surveying provides a constant that can be modelled and used to correct any relative locational uncertainty, absolute positioning at sufficient precision and accuracy for swath mapping remains problematic. In response to these uncertainties, we present a method of navigation correction that provides high-precision, internally consistent positioning and external accuracy. Using features identified on overlapping near-bottom multibeam bathymetry swathes, a correlation can be made between adjacent survey tracks. Internal consistency of the survey can be achieved by matching contours of these features by warping adjacent swaths to fit one another. We find that contour matching is extremely effective as the human eye is particularly good at identifying similar feature patterns, and the contours allow control points to be identified at sufficient spatial resolution to match that of the swath data, and then co-located with lower resolution shipboard swath maps. Examples of swath data from a variety of AUV and ROV systems will be presented including those from the deepest hydrothermal vent

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

    SciTech Connect

    Rettura, A.; Stern, D.; Martinez-Manso, J.; Gettings, D.; Gonzalez, A. H.; Mei, S.; Ashby, M. L. N.; Brodwin, M.; Stanford, S. A.; Bartlett, J. G.

    2014-12-20

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

  9. Candidate Clusters of Galaxies at z > 1.3 Identified in the Spitzer South Pole Telescope Deep Field Survey

    NASA Astrophysics Data System (ADS)

    Rettura, A.; Martinez-Manso, J.; Stern, D.; Mei, S.; Ashby, M. L. N.; Brodwin, M.; Gettings, D.; Gonzalez, A. H.; Stanford, S. A.; Bartlett, J. G.

    2014-12-01

    We present 279 galaxy cluster candidates at z > 1.3 selected from the 94 deg2 Spitzer South Pole Telescope Deep Field (SSDF) survey. We use a simple algorithm to select candidate high-redshift clusters of galaxies based on Spitzer/IRAC mid-infrared data combined with shallow all-sky optical data. We identify distant cluster candidates adopting an overdensity threshold that results in a high purity (80%) cluster sample based on tests in the Spitzer Deep, Wide-Field Survey of the Boötes field. Our simple algorithm detects all three 1.4 < z <= 1.75 X-ray detected clusters in the Boötes field. The uniqueness of the SSDF survey resides not just in its area, one of the largest contiguous extragalactic fields observed with Spitzer, but also in its deep, multi-wavelength coverage by the South Pole Telescope (SPT), Herschel/SPIRE, and XMM-Newton. This rich data set will allow direct or stacked measurements of Sunyaev-Zel'dovich effect decrements or X-ray masses for many of the SSDF clusters presented here, and enable a systematic study of the most distant clusters on an unprecedented scale. We measure the angular correlation function of our sample and find that these candidates show strong clustering. Employing the COSMOS/UltraVista photometric catalog in order to infer the redshift distribution of our cluster selection, we find that these clusters have a comoving number density nc = (0.7+6.3-0.6) × 10-7 h3 {Mpc}-3 and a spatial clustering correlation scale length r 0 = (32 ± 7) h -1 Mpc. Assuming our sample is comprised of dark matter halos above a characteristic minimum mass, M min, we derive that at z = 1.5 these clusters reside in halos larger than Mmin = 1.5+0.9-0.7 × 1014 h-1 M⊙ . We find that the mean mass of our cluster sample is equal to Mmean = 1.9+1.0-0.8 × 1014 h-1 M⊙ ; thus, our sample contains the progenitors of present-day massive galaxy clusters.

  10. CHILES Con Pol: Probing galaxy evolution, the dark Universe, and cosmic magnetism with a deep 1000 hour Jansky VLA survey

    NASA Astrophysics Data System (ADS)

    Hales, Christopher A.; Chiles Con Pol Collaboration

    2014-04-01

    We recently started a 1000 hour campaign to observe 0.2 square degrees of the COSMOS field in full polarization continuum at 1.4 GHz with the Jansky VLA, as part of a joint program with the spectral line COSMOS HI Large Extragalactic Survey (CHILES). When complete, we expect our CHILES Continuum Polarization (CHILES Con Pol) survey to reach an unprecedented SKA-era sensitivity of 0.7 uJy per 4 arcsecond FWHM beam. Here we present the key goals of CHILES Con Pol, which are to (i) produce a source catalog of legacy value to the astronomical community, (ii) measure differential source counts in total intensity, linear polarization, and circular polarization in order to constrain the redshift and luminosity distributions of source populations, (iii) perform a novel weak lensing study using radio polarization as an indicator of intrinsic alignment to better study dark energy and dark matter, and (iv) probe the unknown origin of cosmic magnetism by measuring the strength and structure of intergalactic magnetic fields in the filaments of large scale structure. The CHILES Con Pol source catalog will be a useful resource for upcoming wide-field surveys by acting as a training set for machine learning algorithms, which can then be used to identify and classify radio sources in regions lacking deep multiwavelength coverage.

  11. Mapping the deep: The past and future promise of transneptunian surveys

    NASA Astrophysics Data System (ADS)

    Bannister, M.

    2014-07-01

    Exploring the populations and structure of the outer Solar System requires us to examine the sky. The improving sophistication of astronomical techniques have brought us in the last century from painstaking naked-eye examination of photographic plates to identify moving sources, to supercomputer-powered image subtraction that can pull moving sources from the depths of the Galactic plane. Such advances in our ability to discover new objects have allowed us to build an understanding of the Solar System's distant populations. The continued effort to survey the sky for new discoveries has explored the phase space of much of the transneptunian (TNO) size distribution. At the largest end, from wide-field surveys with small-to-medium optical telescopes in both North and Southern Hemispheres, the dwarf planets are now complete to m˜19.5 (Schwamb et al. 2014) and nearing completion to m˜21.5. Infrared surveys such as WISE have constrained the absence of a brown dwarf or large gas giant planet such that there can be no Saturn out to 28,000 au and no Jupiter out to 82,000 au (Luhman 2014). Similarly, pulsar timing measurements exclude line-of-sight shifts of the Solar System's barycentre due to any lurking giant planet (Verbiest et al. 2008); such timing measurements will only be improved by the Square Kilometre Array's all-sky decadal measurements of pulsars (Seto & Cooray 2007). The smaller, more abundant TNOs have been slowly constrained by surveys on larger facilities (as listed in Kavelaars et al and Petit et al. 2008): their part of the size distribution has a clear change in slope near H of 7 (Fraser et al. 2014). Characterisation of objects for their size, albedo, thermal properties and density has followed more slowly: Spitzer and Herschel have given us thermal properties; broad-band photometric surveys have shown that the colours of TNOs present distinct surface classes, ranging from the reddest in the Solar System to fully neutral reflectors; while large

  12. A Survey Analysis of Alcohol Use at a Black University in the Deep South.

    ERIC Educational Resources Information Center

    Grenier, Charles E.; Borskey, Erma J.; Folse, Debbie W.

    1998-01-01

    Presents findings from a scientific survey of student drug and alcohol behavior at Southern University, an all-black university. Results indicate that alcohol and wine coolers are the drinks of choice. Most of the students are moderate drinkers; however, 13% can be classified as relatively high risk. (MKA)

  13. Feasibility of a time-domain electromagnetic survey for mapping deep-sea hydrothermal deposits

    NASA Astrophysics Data System (ADS)

    Jang, H.; KIM, H. J.

    2014-12-01

    Marine controlled-source electromagnetic (CSEM) surveying has already become a popular tool for hydrocarbon exploration. Possible targets of the marine CSEM survey, other than hydrocarbon, may be marine hydrothermal mineral deposits. In transient EM (TEM) measurements, secondary fields which contain information on hydrothermal deposits in the seafloor can be measured in the absence of strong primary fields. The TEM system is useful to the development of compact, autonomous instruments which are well suited to submersible-based surveys. In this paper, we investigate the possibility of applying an in-loop TEM system to the detection of marine hydrothermal deposits through a one-dimensional modeling and inversion study. The feasibility study showed that TEM responses are very sensitive to a highly conductive layer. Time-domain target responses are larger and appear earlier in horizontal magnetic fields than in vertical ones. An inverse problem is formulated with the Gauss-Newton method and solved with the damped and smoothness-constrained least-squares approach. The test example for a marine hydrothermal TEM survey demonstrated that the depth extent, conductivity and thickness of the highly conductive layer are well resolved.

  14. A Survey Analysis of Alcohol Use at a Black University in the Deep South.

    ERIC Educational Resources Information Center

    Grenier, Charles E.; Borskey, Erma J.; Folse, Debbie W.

    1998-01-01

    Presents findings from a scientific survey of student drug and alcohol behavior at Southern University, an all-black university. Results indicate that alcohol and wine coolers are the drinks of choice. Most of the students are moderate drinkers; however, 13% can be classified as relatively high risk. (MKA)

  15. A Deep Proper Motion Catalog Within the Sloan Digital Sky Survey Footprint

    DTIC Science & Technology

    2014-11-13

    research. 2. OBSERVATIONS The initial survey was conducted using the 90prime prime focus wide-field imager on the Steward Observatory Bok 90 inch telescope...at low and high R.A. within the north galactic cap region tend to be observed further from the meridian and at higher zenith distance. The SDSS +USNO-B

  16. CHILES Con Pol: An ultra-deep JVLA survey probing galaxy evolution and cosmic magnetism

    NASA Astrophysics Data System (ADS)

    Hales, Christopher A.; Momjian, Emmanuel; van Gorkom, Jacqueline; Rupen, Michael P.; Greiner, Maksim; Ensslin, Torsten A.; Bonzini, Margherita; Padovani, Paolo; Harrison, Ian; Brown, Michael L.; Gim, Hansung; Yun, Min S.; Maddox, Natasha; Stewart, Adam; Fender, Rob P.; Tremou, Evangelia; Chomiuk, Laura; Peters, Charee; Wilcots, Eric M.; Lazio, Joseph

    2015-08-01

    We are undertaking a 1000 hour campaign with the Karl G. Jansky VLA to survey 0.2 square degrees of the COSMOS field in full polarization continuum at 1.4 GHz. Our observations are part of a joint program with the spectral line COSMOS HI Large Extragalactic Survey (CHILES). When complete, we expect our CHILES Continuum Polarization (CHILES Con Pol) survey to reach an SKA-era sensitivity of 500 nJy per 4 arcsecond resolving beam, the deepest view of the radio sky yet. CHILES Con Pol will open new and fertile parameter space, with sensitivity to star formation rates of 10 Msun per year out to an unprecedented redshift of z=2, and ultra-luminous infrared galaxies and sub-millimeter galaxies out to redshifts of z=8 and beyond. This rich resource will extend the utility of radio band studies beyond the usual radio quasar and radio galaxy populations, opening sensitivity to the starforming and radio-quiet AGN populations that form the bulk of extragalactic sources detected in the optical, X-ray, and infrared bands. In this talk I will outline the key science of CHILES Con Pol, including galaxy evolution and novel measurements of intergalactic magnetic fields. I will present initial results from the first 180 hours of the survey and describe our forthcoming Data Release 1. I invite the astronomical community to consider unique science that can be pursued with CHILES Con Pol radio data.

  17. A DEEP, WIDE-FIELD H{alpha} SURVEY OF NEARBY CLUSTERS OF GALAXIES: DATA

    SciTech Connect

    Sakai, Shoko; Kennicutt, Robert C. Jr.; Moss, Chris

    2012-04-01

    We present the results of a wide-field H{alpha} imaging survey of eight nearby (z = 0.02-0.03) Abell clusters. We have measured H{alpha} fluxes and equivalent widths for 465 galaxies, of which 360 are new detections. The survey was designed to obtain complete emission-line-selected inventories of star-forming galaxies in the inner regions of these clusters, extending to star formation rates below 0.1 M{sub Sun} yr{sup -1}. This paper describes the observations, data processing, and source identification procedures, and presents an H{alpha} and R-band catalog of detected cluster members and other candidates. Future papers in the series will use these data to study the completeness of spectroscopically based star formation surveys, and to quantify the effects of cluster environment on the present-day populations of star-forming galaxies. The data will also provide a valuable foundation for imaging surveys of redshifted H{alpha} emission in more distant clusters.

  18. The optical identification content of the Einstein Observatory deep X-ray survey of a region in Pavo

    NASA Technical Reports Server (NTRS)

    Griffiths, R. E.; Murray, S. S.; Giacconi, R.; Bechtold, J.; Murdin, P.; Smith, M.; Macgillivray, H. T.; Ward, M.; Danziger, J.; Lub, J.

    1983-01-01

    Results are presented from the Einstein deep X-ray survey in Pavo, with correlated optical and radio observations of a complete sample of candidate identifications. There are 16 X-ray sources detected with positional accuracy better than 10 arcsec, of which five are identified, with a further seven (and a maximum nine) probable identifications. Of the identified sources, four are QSOs with J-magnitude about 20 (one is an inverted spectrum radio source) and one is associated with extended emission from a pair or cluster of galaxies. Of the probable identifications, one is a galaxy and the rest are a subset of a yellow stellar object population which may also be QSOs. Identifications with QSOs and QSO candidates with J less than 24 account for 60-80 percent of the detected sources.

  19. The ALMA Patchy Deep Survey: A Blind Search for [CII] Emitters at z˜ 4.5

    NASA Astrophysics Data System (ADS)

    Matsuda, Y.; APDS Team

    2015-12-01

    We present an initial result of a blind search for [CII] emitters at z˜ 4.5 using ALMA archival data. We used extra-galactic, band 7 data from eight Cycle 0 projects and searched for line emitters in the continuum-subtracted data cubes. However, we could not detect any new line emitters above a 6-σ significance level. This result provides upper limits to the z˜ 4.5 [CII] luminosity function down to L([CII])˜108 L⊙ (or SFR˜10 M⊙ yr-1). This work demonstated that we will be able to constrain the cosmic star-formation rate density by collecting archival data of Cycle 1 and 2 as the ALMA Patchy Deep Survey.

  20. Documentation for the machine-readable version of a deep objective-prism survey for large Magellanic cloud members

    NASA Technical Reports Server (NTRS)

    Warren, W. H., Jr.

    1982-01-01

    This catalog contains 1273 proven or probable Large Magellanic Cloud (LMC) members, as found on deep objective-prism plates taken with the Curtis Schmidt telescope at Cerro Tololo Inter-American Observatory in Chile. The stars are generally brighter than about photographic magnitude 14. Approximate spectral types were determined by examination of the 580 A/mm objective-prism spectra; approximate 1975 positions were obtained by measuring relative to the 1975 coordinate grids on the Uppsala-Mount Stromlo Atlas of the LMC (Gascoigne and Westerlund 1961), and approximate photographic magnitudes were determined by averaging image density measures from the plates and image-diameter measures on the 'B' charts. The machine-readable version of the LMC survey catalog is described to enable users to read and process the tape file without problems or guesswork.

  1. THE VERY LARGE ARRAY 1.4 GHz SURVEY OF THE EXTENDED CHANDRA DEEP FIELD SOUTH: SECOND DATA RELEASE

    SciTech Connect

    Miller, Neal A.; Bonzini, Margherita; Mainieri, Vincenzo; Padovani, Paolo; Rosati, Piero; Fomalont, Edward B.; Kellermann, Kenneth I.; Tozzi, Paolo; Vattakunnel, Shaji

    2013-04-01

    Deep radio observations at 1.4 GHz for the Extended Chandra Deep Field South were performed in 2007 June through September and presented in a first data release. The survey was made using six separate pointings of the Very Large Array with over 40 hr of observation per pointing. In the current paper, we improve on the data reduction to produce a second data release (DR2) mosaic image. This DR2 image covers an area of about a third of a square degree, reaches a best rms sensitivity of 6 {mu}Jy, and has a typical sensitivity of 7.4 {mu}Jy per 2.''8 by 1.''6 beam. We also present a more comprehensive catalog, including sources down to peak flux densities of five or more times the local rms noise along with information on source sizes and relevant pointing data. We discuss in some detail the consideration of whether sources are resolved under the complication of a radio image created as a mosaic of separate pointings each suffering some degree of bandwidth smearing, and the accurate evaluation of the flux densities of such sources. Finally, the radio morphologies and optical/near-IR counterpart identifications are used to identify 17 likely multiple-component sources and arrive at a catalog of 883 radio sources, which is roughly double the number of sources contained in the first data release.

  2. Pharmacological agents as cerebral protectants during deep hypothermic circulatory arrest in adult thoracic aortic surgery. A survey of current practice.

    PubMed

    Dewhurst, A T; Moore, S J; Liban, J B

    2002-10-01

    A postal survey was sent to members of the Association of Cardiothoracic Anaesthetists to ascertain current practice in the use of pharmacological agents as cerebral protectants during deep hypothermic circulatory arrest. The response rate was 60%. Eighty-three per cent of respondents used some form of pharmacological agent specifically for cerebral protection. Fifty-nine per cent of respondents used thiopental, 29% used propofol and 48% used a variety of other agents, the most common of these being a steroid. There were variations in the dose and timing of administration of drugs. Few respondents believed that there was a body of evidence to support this use of pharmacological agents. Only 35% of respondents believed there to be sufficient evidence to support the use of thiopental. Similarly, only 11% of respondents believe that there is evidence supporting the use of propofol, and 16% the use of steroids. The above findings demonstrate that it would not be possible to create a "best practice" set of guidelines at present. A national database of all cases of adult thoracic surgery involving deep hypothermic cardiac arrest, with methodology and outcome, could probably establish such guidelines, evidence based.

  3. VizieR Online Data Catalog: DEEP Groth Strip Survey. VIII. (Koo+, 2005)

    NASA Astrophysics Data System (ADS)

    Koo, D. C.; Simard, L.; Willmer, C. N. A.; Gebhardt, K.; Bouwens, R. J.; Kauffmann, G.; Crosby, T.; Faber, S. M.; Harker, J.; Sarajedini, V. L.; Vogt, N. P.; Weiner, B. J.; Phillips, A. J.; Im, M.; Wu, K. L.

    2005-08-01

    We present a candidate sample of luminous bulges (including ellipticals) found within the Groth Strip Survey (GSS), with spectroscopic redshifts of 0.731/4 profiles and luminosities brighter than IAB=24. Although larger samples of distant early-type galaxies exist, this is the largest and most homogeneous sample of bulges at z~1 with spectroscopy. A brighter subset of 52 objects with added structural constraints defines our "quality sample" that is used to explore bulge luminosities and colors. (3 data files).

  4. The Sloan Digital Sky Survey COADD: 275 deg{sup 2} of deep Sloan Digital Sky Survey imaging on stripe 82

    SciTech Connect

    Annis, James; Soares-Santos, Marcelle; Dodelson, Scott; Hao, Jiangang; Jester, Sebastian; Johnston, David E.; Kubo, Jeffrey M.; Lampeitl, Hubert; Lin, Huan; Miknaitis, Gajus; Yanny, Brian; Strauss, Michael A.; Gunn, James E.; Lupton, Robert H.; Becker, Andrew C.; Ivezić, Željko; Fan, Xiaohui; Jiang, Linhua; Seo, Hee-Jong; Simet, Melanie

    2014-10-20

    We present details of the construction and characterization of the coaddition of the Sloan Digital Sky Survey (SDSS) Stripe 82 ugriz imaging data. This survey consists of 275 deg{sup 2} of repeated scanning by the SDSS camera over –50° ≤ α ≤ 60° and –1.°25 ≤ δ ≤ +1.°25 centered on the Celestial Equator. Each piece of sky has ∼20 runs contributing and thus reaches ∼2 mag fainter than the SDSS single pass data, i.e., to r ∼ 23.5 for galaxies. We discuss the image processing of the coaddition, the modeling of the point-spread function (PSF), the calibration, and the production of standard SDSS catalogs. The data have an r-band median seeing of 1.''1 and are calibrated to ≤1%. Star color-color, number counts, and PSF size versus modeled size plots show that the modeling of the PSF is good enough for precision five-band photometry. Structure in the PSF model versus magnitude plot indicates minor PSF modeling errors, leading to misclassification of stars as galaxies, as verified using VVDS spectroscopy. There are a variety of uses for this wide-angle deep imaging data, including galactic structure, photometric redshift computation, cluster finding and cross wavelength measurements, weak lensing cluster mass calibrations, and cosmic shear measurements.

  5. The VIMOS-VLT Deep Survey. Galaxy luminosity function per morphological type up to z = 1.2

    NASA Astrophysics Data System (ADS)

    Ilbert, O.; Lauger, S.; Tresse, L.; Buat, V.; Arnouts, S.; Le Fèvre, O.; Burgarella, D.; Zucca, E.; Bardelli, S.; Zamorani, G.; Bottini, D.; Garilli, B.; Le Brun, V.; Maccagni, D.; Picat, J.-P.; Scaramella, R.; Scodeggio, M.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnaboldi, M.; Bolzonella, M.; Cappi, A.; Charlot, S.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Iovino, A.; McCracken, H. J.; Marano, B.; Marinoni, C.; Mathez, G.; Mazure, A.; Meneux, B.; Merighi, R.; Paltani, S.; Pello, R.; Pollo, A.; Pozzetti, L.; Radovich, M.; Bondi, M.; Bongiorno, A.; Busarello, G.; Ciliegi, P.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2006-07-01

    Aims.We have computed the evolution of the rest-frame B-band luminosity function (LF) for bulge and disk-dominated galaxies since z=1.2. Methods: .We use a sample of 605 spectroscopic redshifts with IAB≤ 24 in the Chandra Deep Field South from the VIMOS-VLT Deep Survey, 3555 galaxies with photometric redshifts from the COMBO-17 multi-color data, coupled with multi-color HST/ACS images from the Great Observatories Origin Deep Survey. We split the sample in bulge- and disk-dominated populations on the basis of asymmetry and concentration parameters measured in the rest-frame B-band. Results: .We find that at z=0.4-0.8, the LF slope is significantly steeper for the disk-dominated population (α=-1.19 ± 0.07) compared to the bulge-dominated population (α=-0.53 ± 0.13). The LF of the bulge-dominated population is composed of two distinct populations separated in rest-frame color: 68% of red (B-I)AB>0.9 and bright galaxies showing a strongly decreasing LF slope α=+0.55 ± 0.21, and 32% of blue (B-I)AB<0.9 and more compact galaxies which populate the LF faint-end. We observe that red bulge-dominated galaxies are already well in place at z≃1, but the volume density of this population is increasing by a factor 2.7 between z˜ 1 and z˜ 0.6. It may be related to the building-up of massive elliptical galaxies in the hierarchical scenario. In addition, we observe that the blue bulge-dominated population is dimming by 0.7 mag between z˜ 1 and z˜ 0.6. Galaxies in this faint and more compact population could possibly be the progenitors of the local dwarf spheroidal galaxies.

  6. A deep survey for Galactic Wolf-Rayet stars. I - Motivation, search technique, and first results

    NASA Technical Reports Server (NTRS)

    Shara, Michael M.; Smith, Lindsey F.; Potter, Michael; Moffat, Anthony F. J.

    1991-01-01

    Results are presented from a survey of large areas of the southern Milky Way for Wolf-Rayet (WR) stars to 17-18th magnitude, carried out using direct narrowband and broadband Schmidt plates. Thirteen new WR stars were detected in an about 40-deg-sq region in Carina, where 24 WR stars were already known; the new stars were found to be significantly redder, fainter, and farther away than the known stars. Of the new WR stars, 11 are of subtype WN, and two are WC, compared to the 17 WN and seven WC stars among the previously known WR stars in the same area.

  7. Toughening up DELORES: the evolution of the British Antarctic Survey DEep LOok Radio Echo Sounder

    NASA Astrophysics Data System (ADS)

    King, Edward

    2014-05-01

    DELORES is a ground-based radar designed to map the bed and internal structure of thick ice sheets. It is a monopulse radar driven by a ± 2 kV transmitter and using resistively-loaded wire dipole antennae. The recording system is based on a DC-powered digital oscilloscope. All the electronics are housed in weatherproof boxes mounted on sledges and the whole system is towed behind a snowmobile. In the 2013/14 Antarctic field season alone DELORES systems collected over 4000 km of radargrams over ice up to 2.5 km thick. The main operating area has been West Antarctica where surface conditions have varied from deep, soft snow to iron-hard sastrugi. The majority of deployments have been with two-person field teams at locations over 1000 km from support facilities. Therefore the principle design criteria has been 'tough and simple', i.e. make the system robust enough not to break and simple enough to fix with basic tools if it does. Here we describe how the engineering design has evolved over the past eight years and what future developments are planned to achieve greater reliability and versatility.

  8. A survey of deep tissue injury in elite female wheelchair basketball players.

    PubMed

    Shimizu, Yukiyo; Mutsuzaki, Hirotaka; Tachibana, Kaori; Tsunoda, Kenji; Hotta, Kazushi; Fukaya, Takashi; Ikeda, Eiji; Yamazaki, Masashi; Wadano, Yasuyoshi

    2017-01-01

    To investigate deep tissue injuries (DTIs) in elite female wheelchair basketball players and identify factors associated with their occurrence. Study participants were 22 female wheelchair basketball players on the Japanese national team. The sacral and bilateral ischial regions of each participant were examined using ultrasonography to detect DTIs. DTIs were found in 15 players (68.2%). DTIs were more frequent in players with a central nervous system disorder (CNSd) (85.7%) than in those with skeletal system disease (SSd) (37.5%, p = 0.020), and in players using a wheelchair in daily life (84.6%) than those using a wheelchair only for basketball (44.4%, p = 0.046). Players with pelvic instability were more likely to have DTIs (90.9% vs. 45.5%, p = 0.017). DTIs were deeper in the ischial region than the sacral region (p = 0.022). Players with CNSd had more DTIs in sacral regions (90% vs. 10%, p = 0.014). Players with DTIs had lower systolic blood pressure (sBP), red blood cell (RBC) count, and serum creatinine levels (sCr) (all p < 0.05). Ischial DTIs were deeper than sacral DTIs. Players with CNSd had more sacral DTIs than those with SSd. CNSd, wheelchair use in daily life, pelvic instability, and lower sBP, RBC, and sCr increased the risk of DTIs.

  9. VLA observations of unidentified Leiden-Berkeley Deep-Survey sources - Luminosity and redshift dependence of spectral properties

    NASA Technical Reports Server (NTRS)

    Kapahi, Vijay K.; Kulkarni, Vasant K.

    1990-01-01

    VLA observations of a complete subset of the Leiden-Berkeley Deep Survey sources that have S(1.4 GHz) greater than 10 mJy and are not optically identified down to F=22 mag are reported. By comparing the spectral and structural properties of the sources with samples from the literature, an attempt was made to disentangle the luminosity and redshift dependence of the spectral indices of extended emission in radio galaxies and of the incidence of compact steep-spectrum sources. It is found that the fraction of compact sources among those with a steep spectrum is related primarily to redshift, being much larger at high redshifts for sources of similar radio luminosity. Only a weak and marginally significant dependence of spectral indices of the extended sources on luminosity and redshift is found in samples selected at 1.4 and 2.7 GHz. It is pointed out that the much stronger correlation of spectral indices with luminosity may be arising partly from spectral curvature, and partly due to the preferential inclusion of very steep-spectrum sources from high redshift in low-frequency surveys.

  10. The VIMOS VLT deep survey. The evolution of galaxy clustering to z ≃ 2 from first epoch observations

    NASA Astrophysics Data System (ADS)

    Le Fèvre, O.; Guzzo, L.; Meneux, B.; Pollo, A.; Cappi, A.; Colombi, S.; Iovino, A.; Marinoni, C.; McCracken, H. J.; Scaramella, R.; Bottini, D.; Garilli, B.; Le Brun, V.; Maccagni, D.; Picat, J. P.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnaboldi, M.; Arnouts, S.; Bardelli, S.; Blaizot, J.; Bolzonella, M.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Ilbert, O.; Marano, B.; Mathez, G.; Mazure, A.; Merighi, R.; Paltani, S.; Pellò, R.; Pozzetti, L.; Radovich, M.; Zamorani, G.; Zucca, E.; Bondi, M.; Bongiorno, A.; Busarello, G.; Lamareille, F.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2005-09-01

    This paper presents the evolution of the clustering of the main population of galaxies from z≃2 to z=0.2, from the first epoch VIMOS VLT Deep Survey (VVDS), a magnitude limited sample with 17.5 ≤ IAB ≤ 24. The sample allows a direct estimate of evolution from within the same survey over the time base sampled. We have computed the correlation functions ξ(r_p,π) and w_p(r_p), and the correlation length r_0(z), for the VVDS-02h and VVDS-CDFS fields, for a total of 7155 galaxies in a 0.61 deg2 area. We find that the correlation length in this sample slightly increases from z=0.5 to z=1.1, with r_0(z)=2.2{-}2.9 h-1 Mpc (comoving), for galaxies comparable in luminosity to the local 2dFGRS and SDSS samples, indicating that the amplitude of the correlation function was ≃2.5 times lower at z≃1 than observed locally. The correlation length in our lowest redshift bin z=[0.2, 0.5] is r_0=2.2 h-1 Mpc, lower than for any other population at the same redshift, indicating the low clustering of very low luminosity galaxies, 1.5 mag fainter than in the 2dFGRS or SDSS. The correlation length increases to r_0˜3.6 h-1 Mpc at higher redshifts z=[1.3, 2.1], as we are observing increasingly brighter galaxies, comparable to galaxies with MB_{AB}=-20.5 locally. We compare our measurement to the DEEP2 measurements in the range z=[0.7, 1.35] (Coil et al. 2004, ApJ, in press) and find comparable results when applying the same magnitude and color selection criteria as in their survey. The slowly varying clustering of VVDS galaxies as redshift increases is markedly different from the predicted evolution of the clustering of dark matter, indicating that bright galaxies traced higher density peaks when the large scale structures were emerging from the dark matter distribution 9-10 billion years ago, being supporting evidence for a strong evolution of the galaxy vs. dark matter bias.

  11. The Chandra Deep Field-South Survey: 7 Ms Source Catalogs

    NASA Astrophysics Data System (ADS)

    Luo, B.; Brandt, W. N.; Xue, Y. Q.; Lehmer, B.; Alexander, D. M.; Bauer, F. E.; Vito, F.; Yang, G.; Basu-Zych, A. R.; Comastri, A.; Gilli, R.; Gu, Q.-S.; Hornschemeier, A. E.; Koekemoer, A.; Liu, T.; Mainieri, V.; Paolillo, M.; Ranalli, P.; Rosati, P.; Schneider, D. P.; Shemmer, O.; Smail, I.; Sun, M.; Tozzi, P.; Vignali, C.; Wang, J.-X.

    2017-01-01

    We present X-ray source catalogs for the ≈7 Ms exposure of the Chandra Deep Field-South (CDF-S), which covers a total area of 484.2 arcmin2. Utilizing wavdetect for initial source detection and ACIS Extract for photometric extraction and significance assessment, we create a main source catalog containing 1008 sources that are detected in up to three X-ray bands: 0.5–7.0 keV, 0.5–2.0 keV, and 2–7 keV. A supplementary source catalog is also provided, including 47 lower-significance sources that have bright ({K}s≤slant 23) near-infrared counterparts. We identify multiwavelength counterparts for 992 (98.4%) of the main-catalog sources, and we collect redshifts for 986 of these sources, including 653 spectroscopic redshifts and 333 photometric redshifts. Based on the X-ray and multiwavelength properties, we identify 711 active galactic nuclei (AGNs) from the main-catalog sources. Compared to the previous ≈4 Ms CDF-S catalogs, 291 of the main-catalog sources are new detections. We have achieved unprecedented X-ray sensitivity with average flux limits over the central ≈1 arcmin2 region of ≈1.9 × 10‑17, 6.4 × 10‑18, and 2.7 × 10‑17 erg cm‑2 s‑1 in the three X-ray bands, respectively. We provide cumulative number-count measurements observing, for the first time, that normal galaxies start to dominate the X-ray source population at the faintest 0.5–2.0 keV flux levels. The highest X-ray source density reaches ≈50,500 deg‑2, and 47% ± 4% of these sources are AGNs (≈23,900 deg‑2).

  12. Deep optical survey of the stellar content of Sh2-311 region

    NASA Astrophysics Data System (ADS)

    Yadav, Ram Kesh; Pandey, A. K.; Sharma, Saurabh; Jose, J.; Ogura, K.; Kobayashi, N.; Samal, M. R.; Eswaraiah, C.; Chandola, H. C.

    2015-01-01

    The stellar content in and around Sh2-311 region have been studied using the deep optical observations as well as near-infrared (NIR) data from 2MASS. The region contains three clusters, viz. NGC 2467, Haffner 18 and Haffner 19. We have made an attempt to distinguish the stellar content of these individual regions as well as to re-determine their fundamental parameters such as distance, reddening, age, onto the basis of a new and more extended optical and infrared photometric data set. NGC 2467 and Haffner 19 are found to be located in the Perseus arm at the distances of 5.0 ± 0.4 kpc and 5.7 ± 0.4 kpc, respectively, whereas Haffner 18 is located at the distance of 11.2 ± 1.0 kpc. The clusters NGC 2467 and Haffner 19 might have formed from the same molecular cloud, whereas the cluster Haffner 18 is located in the outer galactic arm, i.e. the Norma-Cygnus arm. We identify 8 class II young stellar objects (YSOs) using the NIR (J-H)/(H-K) two colour diagram. We have estimated the age and mass of the YSOs identified in the present work and those by Snider et al. (2009) using the V/(V-I) colour-magnitude diagram. The estimated ages and mass range of the majority of the YSOs are ≲1 Myr and ∼0.4-3.5 M⊙, respectively, indicating that these sources could be T-Tauri stars or their siblings. Spatial distribution of the YSOs shows that some of the YSOs are distributed around the HII region Sh2-311, suggesting a triggered star formation at its periphery.

  13. A deep Spitzer survey of circumstellar disks in the young double cluster, h and χ Persei

    SciTech Connect

    Cloutier, Ryan; Currie, Thayne; Jayawardhana, Ray; Rieke, George H.; Kenyon, Scott J.; Balog, Zoltan E-mail: currie@astro.utoronto.ca E-mail: skenyon@cfa.harvard.edu

    2014-12-01

    We analyze very deep Infrared Array Camera and Multiband Imaging Photometer for Spitzer (MIPS) photometry of ∼12, 500 members of the 14 Myr old Double Cluster, h and χ Persei, building upon our earlier, shallower Spitzer Cycle 1 studies. Numerous likely members show infrared (IR) excesses at 8 μm and 24 μm, indicative of circumstellar dust. The frequency of stars with 8 μm excess is at least 2% for our entire sample, slightly lower (higher) for B/A stars (later type, lower mass stars). Optical spectroscopy also identifies gas in about 2% of systems, but with no clear trend between the presence of dust and gas. Spectral energy distribution modeling of 18 sources with detections at optical wavelengths through MIPS 24 μm reveals a diverse set of disk evolutionary states, including a high fraction of transitional disks, though similar data for all disk-bearing members would provide constraints. Using Monte Carlo simulations, we combine our results with those for other young clusters to study the global evolution of dust/gas disks. For nominal cluster ages, the e-folding times (τ{sub 0}) for the frequency of warm dust and gas are 2.75 Myr and 1.75 Myr, respectively. Assuming a revised set of ages for some clusters, these timescales increase to 5.75 and 3.75 Myr, respectively, implying a significantly longer typical protoplanetary disk lifetime than previously thought. In both cases, the transitional disk duration, averaged over multiple evolutionary pathways, is ≈1 Myr. Finally, 24 μm excess frequencies for 4-6 M {sub ☉} stars appear lower than for 1-2.5 M {sub ☉} stars in other 10-30 Myr old clusters.

  14. Atwater Valley Deep-Towed Sidescan Sonar Imagery and Bathymetric Survey

    SciTech Connect

    Joan M. Gardner; Mike Czarnecki; Rick Hagen; Clyde Nishimura; Warren Wood; Chad Vaughn; Jody Bruton; Pat Hart; Emil Bergeron; Deborah Hutchinson

    2005-11-22

    The purpose of this project was to conduct detailed surface mapping of one of the areas drilled by the Joint Industry Project with ChevronTexaco to understand gas hydrates in the Gulf of Mexico. The gently sloping, mostly flat floor of the Mississippi Canyon is interrupted by mounds and depressions that presumably reflect the complex geology and geohydrology related to turbidite deposition and pervasive salt tectonism. The seafloor mounds we mapped in this study occur in approximately 1300 water depth along the floor of the Mississippi Canyon in lease block areas Atwater Valley 13 and 14. High resolution sidescan sonar (100 kHz and 500 kHz) backscatter imagery, and chirp sub-bottom profiler data were collected using the DT1 deep-towed oceanographic mapping instrument, concentrating on the region directly adjacent to and surrounding two mounds identified as, mounds D and F, and in the region directly adjacent to and surrounding the mounds. The backscatter data have been mosaiced and normalized to provide information on the shape and extent of the mounds, the possible lateral extent of fauna, such as mussel and clam fields on the mounds, possible seep related flows and the occurrence of carbonate material. The extent of a mudflow can be mapped on the southeastern side of mound F. The backscatter data show extremely high-resolution detail about the shape, relief, and morphology of the mounds. This information, coupled with porewater chemistry , DTAGS and heatflow data form a coherent picture of possible mechanics for fluid venting and flora/fauna of the seeps in this region.

  15. A Deep Spitzer Survey of Circumstellar Disks in the Young Double Cluster, h and χ Persei

    NASA Astrophysics Data System (ADS)

    Cloutier, Ryan; Currie, Thayne; Rieke, George H.; Kenyon, Scott J.; Balog, Zoltan; Jayawardhana, Ray

    2014-12-01

    We analyze very deep Infrared Array Camera and Multiband Imaging Photometer for Spitzer (MIPS) photometry of ~12, 500 members of the 14 Myr old Double Cluster, h and χ Persei, building upon our earlier, shallower Spitzer Cycle 1 studies. Numerous likely members show infrared (IR) excesses at 8 μm and 24 μm, indicative of circumstellar dust. The frequency of stars with 8 μm excess is at least 2% for our entire sample, slightly lower (higher) for B/A stars (later type, lower mass stars). Optical spectroscopy also identifies gas in about 2% of systems, but with no clear trend between the presence of dust and gas. Spectral energy distribution modeling of 18 sources with detections at optical wavelengths through MIPS 24 μm reveals a diverse set of disk evolutionary states, including a high fraction of transitional disks, though similar data for all disk-bearing members would provide constraints. Using Monte Carlo simulations, we combine our results with those for other young clusters to study the global evolution of dust/gas disks. For nominal cluster ages, the e-folding times (τ0) for the frequency of warm dust and gas are 2.75 Myr and 1.75 Myr, respectively. Assuming a revised set of ages for some clusters, these timescales increase to 5.75 and 3.75 Myr, respectively, implying a significantly longer typical protoplanetary disk lifetime than previously thought. In both cases, the transitional disk duration, averaged over multiple evolutionary pathways, is ≈1 Myr. Finally, 24 μm excess frequencies for 4-6 M ⊙ stars appear lower than for 1-2.5 M ⊙ stars in other 10-30 Myr old clusters.

  16. M Dwarf Activity in the Pan-STARRS1 Medium-Deep Survey: First Catalog and Rotation Periods

    NASA Astrophysics Data System (ADS)

    Kado-Fong, E.; Williams, P. K. G.; Mann, A. W.; Berger, E.; Burgett, W. S.; Chambers, K. C.; Huber, M. E.; Kaiser, N.; Kudritzki, R.-P.; Magnier, E. A.; Rest, A.; Wainscoat, R. J.; Waters, C.

    2016-12-01

    We report on an ongoing project to investigate activity in the M dwarf stellar population observed by the Pan-STARRS1 Medium-Deep Survey (PS1-MDS). Using a custom-built pipeline, we refine an initial sample of ˜4 million sources in PS1-MDS to a sample of 184,148 candidate cool stars using color cuts. Motivated by the well-known relationship between rotation and stellar activity, we use a multiband periodogram analysis and visual vetting to identify 270 sources that are likely rotating M dwarfs. We derive a new set of polynomials relating M dwarf PS1 colors to fundamental stellar parameters and use them to estimate the masses, distances, effective temperatures, and bolometric luminosities of our sample. We present a catalog containing these values, our measured rotation periods, and cross-matches to other surveys. Our final sample spans periods of ≲1-130 days in stars with estimated effective temperatures of ˜2700-4000 K. Twenty-two of our sources have X-ray cross-matches, and they are found to be relatively X-ray bright as would be expected from selection effects. Our data set provides evidence that Kepler-based searches have not been sensitive to very slowly rotating stars (P rot ≳ 70 day), implying that the observed emergence of very slow rotators in studies of low-mass stars may be a systematic effect. We also see a lack of low-amplitude (<2%) variability in objects with intermediate (10-40 day) rotation periods, which, considered in conjunction with other observational results, may be a signpost of a loss of magnetic complexity associated with a phase of rapid spin-down in intermediate-age M dwarfs. This work represents just a first step in exploring stellar variability in data from the PS1-MDS and, in the farther future, Large Synoptic Survey Telescope.

  17. Galaxy evolution from deep multi-wavelength infrared surveys: a prelude to Herschel

    NASA Astrophysics Data System (ADS)

    Franceschini, A.; Rodighiero, G.; Vaccari, M.; Berta, S.; Marchetti, L.; Mainetti, G.

    2010-07-01

    Context. Studies of the generation and assembly of stellar populations in galaxies largely benefit from far-IR observations, considering that the IR flux is a close prior to the rate of star formation (the bulk of which happens in dust-obscured environments). At the same time, major episodes of nuclear AGN accretion are also dust-obscured and visible in the IR. Aims: At the end of the Spitzer cryogenic mission and the onset of the Herschel era, we review our current knowledge of galaxy evolution at IR wavelengths, and model it to achieve as far as a complete view of the evolution of cosmic sources. We also develop new tools for the analysis of background fluctuations to constrain source counts in regimes of high confusion, as it happens for the Herschel sub-mm surveys. Methods: We analysed a wide variety of new data on galaxy evolution and high-redshift source populations from Spitzer cosmological surveys, and confront them with complementary data from mm ground-based observations and constraints from the far-IR diffuse radiation, as well as preliminary results from Herschel surveys. Results: These data confirm earlier indications about a very rapid increase in galaxy volume emissivity with redshift up to z ≃ 1 [ ρ(z) ∝ (1+z)4] , the fastest evolution rate observed for galaxies at any wavelengths. The observed Spitzer counts require a combination of fast evolution for the dominant population and a bumpy spectrum with substantial PAH emission at z ~ 1 to 2. Number counts at long wavelengths (70 through 1100 μm) confirm these results. All the present data require that the fast observed evolution from z = 0 to 1 flattens around redshift 1 and then keeps approximately constant up to z ≃ 2.5 at least. Our estimated redshift-dependent bolometric comoving energy density keeps lower at z ⪆ 1.5 than some previously published results based on either large extinction corrections, or large spectral extrapolations. Conclusions: The present-day IR/sub-mm data provide

  18. A Deep Multicolor Survey. II. Initial Spectroscopy and Comparison with Expected Quasar Number Counts

    NASA Astrophysics Data System (ADS)

    Hall, Patrick B.; Osmer, Patrick S.; Green, Richard F.; Porter, Alain C.; Warren, Stephen J.

    1996-05-01

    We have used the KPNO 4 m Mayall telescope to image 0.83 deg^2^ of sky in six fields at high Galactic latitude in six filters spanning 3000- 10000 A to magnitude limits ranging from 22.1 to 23.8. As a first use of this database, we have conducted a multicolor survey for quasars. We discuss various methods of selecting outliers in different color-color diagrams and multicolor space that have been used to identify quasars at all redshifts from their colors alone. We discuss the initial results of our program of spectroscopic identification which has so far resulted in the identification of over 40 faint quasars, including one at z > 4, a similar number of compact narrow emission-line galaxies, and a number of unusual and potentially interesting stars. We use these spectroscopic results, along with extensive simulations of quasar spectra, to study the efficiency of our candidate selection procedures. Finally, we compare the number counts of our quasars and quasar candidates to the expected numbers based on previous studies of the quasar luminosity function. The agreement of our observations with these expectations is good in most cases. However, we do estimate that our survey contains more quasars with B < 21 and z < 2.3 than expected from the results published by Koo & Kron in 1988 and more z > 3 quasars than expected from the results published by Warren, Hewett, & Osmer in 1994, both at the 3 σ level. Additional spectroscopic observations will be required to confirm or refute these excesses.

  19. A multiwavelength study of the IRAS Deep Survey galaxy sample. III. Spectral classification and dynamical properties

    NASA Astrophysics Data System (ADS)

    Bettoni, D.; Mazzei, P.; Della Valle, A.

    2012-02-01

    Context. The infrared deep sample (IDS), in the north ecliptical polar region (NEPR), is the first complete, far-IR selected sample, on which numerous studies of galaxy evolution are based. Such a sample allows direct investigation of the evolution of dusty galaxies up to a redshift of about 0.3, where the global star formation rate is known to evolve very fast. As discussed in previous papers, we performed optical and IR (ISOCAM, 15 μm,) follow-up of its galaxies and exploited our IR observations to correct the 60 μm fluxes for confusion effects and observational biases. In them we found indications of a significant incompleteness of IDS sample below S(60) ≃ 80 mJy. We constructed 15 μm and far-IR (60 μm) luminosity functions of a complete sample of 56 ISO/IRAS sources. Aims: Here we present and analyze the spectral classification of several galaxies in the IDS sample together with rotation curves which allow estimating the lower mass limits of a subsample of objects. Methods: We measured fluxes and intensity ratios of the emission lines in the visible region of the spectrum (λ4000-9000 Å) for 75 galaxy members. Moreover, for some of them (55%), the spectra obtained with the Keck II telescope have sufficient wavelength and spatial resolution to derive their rotation curve. Results: These galaxies turn out to be disk like systems, with a high fraction (~50%) of interacting systems. The spectroscopic classification of 42 galaxies, using the emission-line ratio diagnostic diagrams, shows that the NEPR sample is predominantly composed of starburst galaxies (71%), while the fraction of AGNs (7%) and LINERs (21%) is small. The dynamical analysis allows us to estimate the lower mass limits of 39 galaxies. Conclusions: The rest-frame FIR luminosity distribution of these galaxies spans the same range as that of the FIR selected complete sample, i.e. three orders of magnitude, with the same mean value, log(LFIR) = 10.2. This emphasizes that such galaxies represent

  20. High-resolution simulation of deep pencil beam surveys - analysis of quasi-periodicity

    NASA Astrophysics Data System (ADS)

    Weiss, A. G.; Buchert, T.

    1993-07-01

    We carry out pencil beam constructions in a high-resolution simulation of the large-scale structure of galaxies. The initial density fluctuations are taken to have a truncated power spectrum. All the models have {OMEGA} = 1. As an example we present the results for the case of "Hot-Dark-Matter" (HDM) initial conditions with scale-free n = 1 power index on large scales as a representative of models with sufficient large-scale power. We use an analytic approximation for particle trajectories of a self-gravitating dust continuum and apply a local dynamical biasing of volume elements to identify luminous matter in the model. Using this method, we are able to resolve formally a simulation box of 1200h^-1^ Mpc (e.g. for HDM initial conditions) down to the scale of galactic halos using 2160^3^ particles. We consider this as the minimal resolution necessary for a sensible simulation of deep pencil beam data. Pencil beam probes are taken for a given epoch using the parameters of observed beams. In particular, our analysis concentrates on the detection of a quasi-periodicity in the beam probes using several different methods. The resulting beam ensembles are analyzed statistically using number distributions, pair-count histograms, unnormalized pair-counts, power spectrum analysis and trial-period folding. Periodicities are classified according to their significance level in the power spectrum of the beams. The simulation is designed for application to parameter studies which prepare future observational projects. We find that a large percentage of the beams show quasi- periodicities with periods which cluster at a certain length scale. The periods found range between one and eight times the cutoff length in the initial fluctuation spectrum. At significance levels similar to those of the data of Broadhurst et al. (1990), we find about 15% of the pencil beams to show periodicities, about 30% of which are around the mean separation of rich clusters, while the distribution of

  1. The VIMOS-VLT deep survey. Evolution of the galaxy luminosity function up to z = 2 in first epoch data

    NASA Astrophysics Data System (ADS)

    Ilbert, O.; Tresse, L.; Zucca, E.; Bardelli, S.; Arnouts, S.; Zamorani, G.; Pozzetti, L.; Bottini, D.; Garilli, B.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Picat, J.-P.; Scaramella, R.; Scodeggio, M.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnaboldi, M.; Bolzonella, M.; Cappi, A.; Charlot, S.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Iovino, A.; McCracken, H. J.; Marano, B.; Marinoni, C.; Mathez, G.; Mazure, A.; Meneux, B.; Merighi, R.; Paltani, S.; Pello, R.; Pollo, A.; Radovich, M.; Bondi, M.; Bongiorno, A.; Busarello, G.; Ciliegi, P.; Lamareille, F.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2005-09-01

    We investigate the evolution of the galaxy luminosity function from the VIMOS-VLT Deep Survey (VVDS) from the present to z = 2 in five (U, B, V, R and I) rest-frame band-passes. We use the first epoch VVDS deep sample of 11 034 spectra selected at 17.5 ≤ IAB ≤ 24.0, on which we apply the Algorithm for Luminosity Function (ALF), described in this paper. We observe a substantial evolution with redshift of the global luminosity functions in all bands. From z = 0.05 to z = 2, we measure a brightening of the characteristic magnitude M* included in the magnitude range 1.8-2.5, 1.7-2.4, 1.2-1.9, 1.1-1.8 and 1.0-1.6 in the U, B, V, R and I rest-frame bands, respectively. We confirm this differential evolution of the luminosity function with rest-frame wavelength from the measurement of the comoving density of bright galaxies (M ≤ M*(z = 0.1)). This density increases by a factor of around 2.6, 2.2, 1.8, 1.5, 1.5 between z=0.05 and z=1 in the U, B, V, R, I bands, respectively. We also measure a possible steepening of the faint-end slope of the luminosity functions, with Δα ˜ -0.3 between z=0.05 and z=1, similar in all bands.

  2. CANDELS: THE COSMIC ASSEMBLY NEAR-INFRARED DEEP EXTRAGALACTIC LEGACY SURVEY-THE HUBBLE SPACE TELESCOPE OBSERVATIONS, IMAGING DATA PRODUCTS, AND MOSAICS

    SciTech Connect

    Koekemoer, Anton M.; Ferguson, Henry C.; Grogin, Norman A.; Lotz, Jennifer M.; Lucas, Ray A.; Ogaz, Sara; Rajan, Abhijith; Casertano, Stefano; Dahlen, Tomas; Faber, S. M.; Kocevski, Dale D.; Koo, David C.; Lai, Kamson; McGrath, Elizabeth J.; Strolger, Louis; Castellano, Marco; Dickinson, Mark; and others

    2011-12-01

    This paper describes the Hubble Space Telescope imaging data products and data reduction procedures for the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). This survey is designed to document the evolution of galaxies and black holes at z Almost-Equal-To 1.5-8, and to study Type Ia supernovae at z > 1.5. Five premier multi-wavelength sky regions are selected, each with extensive multi-wavelength observations. The primary CANDELS data consist of imaging obtained in the Wide Field Camera 3 infrared channel (WFC3/IR) and the WFC3 ultraviolet/optical channel, along with the Advanced Camera for Surveys (ACS). The CANDELS/Deep survey covers {approx}125 arcmin{sup 2} within GOODS-N and GOODS-S, while the remainder consists of the CANDELS/Wide survey, achieving a total of {approx}800 arcmin{sup 2} across GOODS and three additional fields (Extended Groth Strip, COSMOS, and Ultra-Deep Survey). We summarize the observational aspects of the survey as motivated by the scientific goals and present a detailed description of the data reduction procedures and products from the survey. Our data reduction methods utilize the most up-to-date calibration files and image combination procedures. We have paid special attention to correcting a range of instrumental effects, including charge transfer efficiency degradation for ACS, removal of electronic bias-striping present in ACS data after Servicing Mission 4, and persistence effects and other artifacts in WFC3/IR. For each field, we release mosaics for individual epochs and eventual mosaics containing data from all epochs combined, to facilitate photometric variability studies and the deepest possible photometry. A more detailed overview of the science goals and observational design of the survey are presented in a companion paper.

  3. A deep proper motion catalog within the Sloan digital sky survey footprint

    SciTech Connect

    Munn, Jeffrey A.; Harris, Hugh C.; Tilleman, Trudy M.; Hippel, Ted von; Kilic, Mukremin; Liebert, James W.; Williams, Kurtis A.; DeGenarro, Steven; Jeffery, Elizabeth E-mail: hch@nofs.navy.mil E-mail: ted.vonhippel@erau.edu E-mail: jamesliebert@gmail.com E-mail: studiofortytwo@yahoo.com

    2014-12-01

    A new proper motion catalog is presented, combining the Sloan Digital Sky Survey (SDSS) with second epoch observations in the r band within a portion of the SDSS imaging footprint. The new observations were obtained with the 90prime camera on the Steward Observatory Bok 90 inch telescope, and the Array Camera on the U.S. Naval Observatory, Flagstaff Station, 1.3 m telescope. The catalog covers 1098 square degrees to r = 22.0, an additional 1521 square degrees to r = 20.9, plus a further 488 square degrees of lesser quality data. Statistical errors in the proper motions range from 5 mas year{sup −1} at the bright end to 15 mas year{sup −1} at the faint end, for a typical epoch difference of six years. Systematic errors are estimated to be roughly 1 mas year{sup −1} for the Array Camera data, and as much as 2–4 mas year{sup −1} for the 90prime data (though typically less). The catalog also includes a second epoch of r band photometry.

  4. Radio properties of M33 supernova remnants: results from a new deep JVLA Survey

    NASA Astrophysics Data System (ADS)

    Long, Knox S.; White, Richard L.; Becker, Robert H.; Helfand, David J.; Blair, William P.; Winkler, P. Frank

    2016-06-01

    We have carried out new 6 and 20 cm observations of M33 with the Jansky Very Large Array, primarily to study the properties of supernova remnants in the galaxy. Our scaled array observations have a limiting sensitivity of about 25 μJy (5σ) and a resolution of 5`` (FWHM), corresponding to a spatial resolution of 20 pc at the distance of M33. We detect about 85 of the SNRs contained in the list of 137 optically identified SNRs described by Long et al. (2010), and a few additional objects from the survey of Lee & Lee (2014). A substantial fraction of the optical SNRs not detected are in regions where emission from H II recombination makes identification of non-thermal emission from the SNR difficult. We also discuss a blind search for SNRs based on the radio emission alone. Of the SNRs we detect in this search at radio wavelengths, 53 have also been detected at X-ray wavelengths. Thus we are able make a direct comparison of the X-ray, optical, and radio properties of the SNRs in M33, the first time that has been possible to a significant extent in an external spiral galaxy.

  5. Deep Photometry of Galaxies in the VEGAS Survey: The Case of NGC 4472

    NASA Astrophysics Data System (ADS)

    Spavone, M.

    The VST-VEGAS project is aimed at observing and studying a rich sample of nearby early-type galaxies in order to systematically characterize their properties over a wide baseline of sizes and out to the faint outskirts where data are rather scarce so far. The external regions of galaxies more easily retain signatures about the formation and evolution mechanisms which shaped them, as their relaxation time are longer, and they are more weakly influenced by processes such as mergers, secular evolution, central black hole activity, and supernova feedback on the ISM, which tend to level age and metallicity gradients. The collection of a wide photometric dataset of a large number of galaxies in various environmental conditions, may help to shed light on these questions. To this end VEGAS exploits the potential of the VLT Survey Telescope (VST) which provides high quality images of 1 deg2 field of view in order to satisfy both the requirement of high resolution data and the need of studying nearby, and thus large, objects. We present a detailed study of the surface photometry of the elliptical galaxy NGC4472 and of smaller ETGs in its field, performed by using new g and i bands images to constrain the formation history of this nearby giant galaxy, and to investigate the presence of very faint substructures in its surroundings.

  6. Morphological Survey of Microbial Mats Near Deep-Sea Thermal Vents †

    PubMed Central

    Jannasch, Holger W.; Wirsen, Carl O.

    1981-01-01

    A microscopic survey is presented of the most commonly observed and morphologically conspicuous microorganisms found attached to natural surfaces or to artificial materials deposited in the immediate vicinity of thermal submarine vents at the Galapagos Rift ocean spreading zone at a depth of 2,550 meters. Of special interest were the following findings: (i) all surfaces intermittently exposed to H2S-containing hydrothermal fluid were covered by layers, ca. 5 to 10 μm thick, of procaryotic, gram-negative cells interspaced with amorphous metal (Mn-Fe) deposits; (ii) although some of the cells were encased by dense metal deposits, there was little apparent correlation between metal deposition and the occurrence of microbial mats, (iii) highly differentiated forms appeared to be analogues of certain cyanobacteria, (iv) isolates from massive mats of a prosthecate bacterium could be identified as Hyphomicrobium spp., (v) intracellular membrane systems similar to those found in methylotrophic and nitrifying bacteria were observed in approximately 20% of the cells composing the mats, (vi) thiosulfate enrichments made from mat material resulted in isolations of different types of sulfur-oxidizing bacteria including the obligately chemolithotrophic genus Thiomicrospira. Images PMID:16345722

  7. The GALEX Time Domain Survey. II. Wavelength-Dependent Variability of Active Galactic Nuclei in the Pan-STARRS1 Medium Deep Survey

    NASA Astrophysics Data System (ADS)

    Hung, T.; Gezari, S.; Jones, D. O.; Kirshner, R. P.; Chornock, R.; Berger, E.; Rest, A.; Huber, M.; Narayan, G.; Scolnic, D.; Waters, C.; Wainscoat, R.; Martin, D. C.; Forster, K.; Neill, J. D.

    2016-12-01

    We analyze the wavelength-dependent variability of a sample of spectroscopically confirmed active galactic nuclei selected from near-UV (NUV) variable sources in the GALEX Time Domain Survey that have a large amplitude of optical variability (difference-flux S/N > 3) in the Pan-STARRS1 Medium Deep Survey (PS1 MDS). By matching GALEX and PS1 epochs in five bands (NUV, g P1, r P1, i P1, z P1) in time, and taking their flux difference, we create co-temporal difference-flux spectral energy distributions ({{Δ }}f{SEDs}) using two chosen epochs for each of the 23 objects in our sample, on timescales of about a year. We confirm the “bluer-when-brighter” trend reported in previous studies, and measure a median spectral index of the {{Δ }}f{SEDs} of {α }λ = 2.1 that is consistent with an accretion disk spectrum. We further fit the {{Δ }}f{SEDs} of each source with a standard accretion disk model in which the accretion rate changes from one epoch to the other. In our sample, 17 out of 23 (∼74%) sources are described well by this variable accretion-rate disk model, with a median average characteristic disk temperature \\bar{T}* of 1.2× {10}5 K that is consistent with the temperatures expected, given the distribution of accretion rates and black hole masses inferred for the sample. Our analysis also shows that the variable accretion rate model is a better fit to the {{Δ }}f{SEDs} than a simple power law.

  8. OT1_sserje01_1: THE HERSCHEL-AKARI NEP DEEP SURVEY: the cosmological history of stellar mass assembly and black hole accretion

    NASA Astrophysics Data System (ADS)

    Serjeant, S.

    2010-07-01

    We propose a far-IR and submm mapping survey of the premier AKARI deep field in the North Ecliptic Pole, in PACS/SPIRE parallel mode. This is the only major deep infrared field not yet covered by Herschel guaranteed or open time key projects. The outstanding and unparalleled continuous mid-IR photometric coverage from AKARI, far better than equivalent Spitzer surveys, enables a wide range of galaxy evolution diagnostics unachievable in any other survey field (including Herschel HerMES/PEP fields), by spanning the wavelengths of redshifted PAH and silicate features and the peak energy output of AGN dust tori. The investment by AKARI in the NEP represents ~10 percent of the entire pointed observations available throughout the lifetime of AKARI. Our proposal remedies the remarkable omission from Herschel's legacy surveys of the premier extragalactic deep field from another IR space telescope. We will simultaneously identify and find photometric redshifts for the Herschel point source population, make stacking analysis detections of the galaxies which dominate the submm extragalactic background light as a function of redshift, determine the bolometric power outputs of the galaxies that dominate the submm background, compare the UV/optical/mid-IR continuum/PAH/far-IR/submm/radio star formation rate estimator in the most comprehensive IR survey data set to date, and track the coupled stellar mass assembly and black hole accretion throughout most of the history of the Universe.

  9. VizieR Online Data Catalog: Deep Objective-Prism Survey for LMC Members (Sanduleak 1970)

    NASA Astrophysics Data System (ADS)

    Sanduleak, N.

    2008-02-01

    The catalog contains 1273 proven or probable Large Magellanic Cloud (LMC) members, identified on plates taken with the Curtis-Schmidt telescope at Cerro Tololo Inter-American Observatory in Chile. The stars are generally brighter than photographic magnitude 14 and are identified on charts published by Hodge and Wright (1967) and reproduced in the source publication (1970CoTol..89....1S). Approximate spectral types were determined by examination of the 580 Angstroms/mm (at H{gamma}) objective-prism spectra; approximate 1975 positions were obtained by measuring relative to the 1975 coordinate grids on the Uppsala-Mount Stromlo Atlas of the LMC (Gascoigne and Westerlund 1961), and approximate photographic magnitudes were determined by averaging image density measures from the plates and image-diameter measures on the "B" charts of Hodge and Wright (1967SAOP.4699....1H). The catalog includes an identification number (Sk), HD(E) number, Cape Photographic Durchmusterung number, right ascension and declination (equinox B1975), spectral type, photographic magnitude, and alternate identifications. The machine version, updated in September 1986, includes corrections supplied by the author in 1985; thus, it differs somewhat from the published version. Accurate positions, and cross-identifications with the modern surveys, were determined by Brian Skiff in 2008, and make up the "sk_pos.dat" file. This work is based on a file prepared through great effort by Mati Morel in 1999. Brian Skiff examined every object on DSS cut-outs to make sure the star chosen matched the Sanduleak charts. The Goddard SkyView utility was used, looking at an 0.07{deg} (4'x4') field from the DSS1 (short-V plate), DSS2 far-red, and 2MASS J-band images. These three have the shallowest effective exposure (these are bright stars!), and usually the best image quality to check for companions etc as well as star colors. Precise coordinates were then obtained via VizieR mainly from UCAC2, but occasionally

  10. A PILOT DEEP SURVEY FOR X-RAY EMISSION FROM fuvAGB STARS

    SciTech Connect

    Sahai, R.; Sanz-Forcada, J.; Sánchez Contreras, C.; Stute, M.

    2015-09-01

    We report the results of a pilot survey for X-ray emission from a newly discovered class of AGB stars with far-ultraviolet excesses (fuvAGB stars) using XMM-Newton and Chandra. We detected X-ray emission in three of six fuvAGB stars observed—the X-ray fluxes are found to vary in a stochastic or quasi-periodic manner on roughly hour-long timescales, and simultaneous UV observations using the Optical Monitor on XMM for these sources show similar variations in the UV flux. These data, together with previous studies, show that X-ray emission is found only in fuvAGB stars. From modeling the spectra, we find that the observed X-ray luminosities are ∼(0.002–0.2) L{sub ⊙} and the X-ray-emitting plasma temperatures are ∼(35–160) × 10{sup 6} K. The high X-ray temperatures argue against the emission arising in stellar coronae, or directly in an accretion shock, unless it occurs on a WD companion. However, none of the detected objects is a known WD-symbiotic star, suggesting that if WD companions are present, they are relatively cool (<20,000 K). In addition, the high X-ray luminosities specifically argue against emission originating in the coronae of main-sequence companions. We discuss several models for the X-ray emission and its variability and find that the most likely scenario for the origin of the X-ray (and FUV) emission involves accretion activity around a companion star, with confinement by strong magnetic fields associated with the companion and/or an accretion disk around it.

  11. Baited camera survey of deep-sea demersal fishes of the West African oil provinces off Angola: 1200-2500m depth, East Atlantic Ocean.

    PubMed

    Jamieson, Alan J; Linley, Thomas D; Craig, Jessica

    2017-08-01

    Deep-sea demersal fish surveys using baited cameras were undertaken in the West African oil provinces between 1297 m and 2453 m depth in 2002, 2005 and 2008. A total of 29 deployments amounting to 16,175 images encountered 31 species of bait attending deep-sea fish from 17 families. The extrapolated species richness was 34, indicating that the survey encountered over 90% of bait attending fish species in this area. The dominant species in the area were the morid Antimora rostrata, the synaphobranchids Synaphobranchus cf. kaupii and Simenchelys parasitica, the somniosid Centroscymnus coelolepis and the zoarcid Pachycara crassiceps. An unusually high diversity of bait attending macrourids was observed in addition to patchy aggregations of zoarcids. This study serves as baseline survey data on which to base future long-term environmental monitoring of fish populations in the vicinity of the West African oil provinces. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. The VIMOS VLT deep survey. First epoch VVDS-deep survey: 11 564 spectra with 17.5 ≤ IAB ≤ 24, and the redshift distribution over 0 ≤ z ≤ 5

    NASA Astrophysics Data System (ADS)

    Le Fèvre, O.; Vettolani, G.; Garilli, B.; Tresse, L.; Bottini, D.; Le Brun, V.; Maccagni, D.; Picat, J. P.; Scaramella, R.; Scodeggio, M.; Zanichelli, A.; Adami, C.; Arnaboldi, M.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Ilbert, O.; Iovino, A.; McCracken, H. J.; Marano, B.; Marinoni, C.; Mathez, G.; Mazure, A.; Meneux, B.; Merighi, R.; Paltani, S.; Pellò, R.; Pollo, A.; Pozzetti, L.; Radovich, M.; Zamorani, G.; Zucca, E.; Bondi, M.; Bongiorno, A.; Busarello, G.; Lamareille, F.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2005-09-01

    This paper presents the “First Epoch” sample from the VIMOS VLT Deep Survey (VVDS). The VVDS goals, observations, data reduction with the VIPGI pipeline and redshift measurement scheme with KBRED are discussed. Data have been obtained with the VIsible Multi Object Spectrograph (VIMOS) on the ESO-VLT UT3, allowing us to observe ≃600 slits simultaneously at a spectral resolution R≃230. A total of 11 564 objects have been observed in the VVDS-02h and VVDS-CDFS “Deep” fields over a total area of 0.61 deg^2, selected solely on the basis of apparent magnitude 17.5 ≤ IAB ≤ 24. The VVDS efficiently covers the redshift range 0 < z ≤ 5. It is successfully going through the “redshift desert” 1.5survey reaches a redshift measurement completeness of 78% overall (93% including less reliable flag 1 objects), with a spatial sampling of the population of galaxies of ~25% and ~30% in the VVDS-02h and VVDS-CDFS respectively. The redshift accuracy measured from repeated observations with VIMOS and comparison to other surveys is ~276 km s-1. From this sample we are able to present for the first time the redshift distribution of a magnitude-limited spectroscopic sample down to IAB=24. The redshift distribution N(z) has a median of z=0.62, z=0.65, z=0.70, and z=0.76, for magnitude-limited samples with IAB≤22.5, 23.0, 23.5 and 24.0 respectively. A high redshift tail above redshift 2 and up to redshift 5 becomes readily apparent for IAB>23.5, probing the bright star-forming population of galaxies. This sample provides an unprecedented dataset to study galaxy evolution over ~90% of the life of the

  13. Low solar elongation searches for NEO: a deep sky test and its implications for survey strategies

    NASA Astrophysics Data System (ADS)

    Boattini, Andrea; Milani, A.; Gronchi, G. F.; Spahr, T.; Valsecchi, G. B.

    2007-05-01

    A survey for NEOs aiming at 90% completeness for a given size range cannot ignore that a significant fraction of the population passes in the neighborhood of opposition either never or very rarely or only in very poor observing conditions. Thus, a fraction of the available telescope time needs to be used at low solar elongations in the so called "sweet spots". However, there are several penalties for such sweet spot observations: i) poorer observing conditions, implying a lower limiting magnitude; ii) shorter available observing time for each night; iii) more difficult orbit determination. Other classes of objects are poorly observed either because of higher apparent magnitude (especially Main Belt Asteroids, MBAs) or because of too slow motion (distant objects); however, this makes easier to find the NEOs. We have tested the observations and the mathematical methods of identification/orbit determination on two sweet spot test runs conducted in 2005. One performed at La Silla (ESO) with the 2.2-m and 3.5-m NTT and the other one conducted at Mauna Kea with 3.6-m CFHT and 8.3-m Subaru. Also, when short arc observations from different observing nights have to be identified, a specific difficulty occurs at the sweet spots: the same set of observations from three nights can be fitted to two incompatible orbits, in most cases including one NEO (often Aten) and one MBA. This can lead to two different failures in deciding wether a NEO has been discovered: a false positive leads to the waste of resources (follow-up, computations) for a MBA which would be more easily discovered at opposition, a false negative leads to the loss of the NEO which may not be reobservable soon. In this way we generated a large number of examples of possible discoveries with two well determined but incompatible solutions. Most of the MBA-NEO alternatives resulted in a known MBA or in a new designated one as soon as it was confirmed by a later observations. Of the 9 real NEOs detected, 1 has been

  14. The ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: Molecular Gas Reservoirs in High-redshift Galaxies

    NASA Astrophysics Data System (ADS)

    Decarli, Roberto; Walter, Fabian; Aravena, Manuel; Carilli, Chris; Bouwens, Rychard; da Cunha, Elisabete; Daddi, Emanuele; Elbaz, David; Riechers, Dominik; Smail, Ian; Swinbank, Mark; Weiss, Axel; Bacon, Roland; Bauer, Franz; Bell, Eric F.; Bertoldi, Frank; Chapman, Scott; Colina, Luis; Cortes, Paulo C.; Cox, Pierre; Gónzalez-López, Jorge; Inami, Hanae; Ivison, Rob; Hodge, Jacqueline; Karim, Alex; Magnelli, Benjamin; Ota, Kazuaki; Popping, Gergö; Rix, Hans-Walter; Sargent, Mark; van der Wel, Arjen; van der Werf, Paul

    2016-12-01

    We study the molecular gas properties of high-z galaxies observed in the ALMA Spectroscopic Survey (ASPECS) that targets an ˜1 arcmin2 region in the Hubble Ultra Deep Field (UDF), a blind survey of CO emission (tracing molecular gas) in the 3 and 1 mm bands. Of a total of 1302 galaxies in the field, 56 have spectroscopic redshifts and correspondingly well-defined physical properties. Among these, 11 have infrared luminosities {L}{IR}\\gt {10}11 {L}⊙ , i.e., a detection in CO emission was expected. Out of these, 7 are detected at various significance in CO, and 4 are undetected in CO emission. In the CO-detected sources, we find CO excitation conditions that are lower than those typically found in starburst/sub-mm galaxy/QSO environments. We use the CO luminosities (including limits for non-detections) to derive molecular gas masses. We discuss our findings in the context of previous molecular gas observations at high redshift (star formation law, gas depletion times, gas fractions): the CO-detected galaxies in the UDF tend to reside on the low-{L}{IR} envelope of the scatter in the {L}{IR}{--}{L}{CO}\\prime relation, but exceptions exist. For the CO-detected sources, we find an average depletion time of ˜1 Gyr, with significant scatter. The average molecular-to-stellar mass ratio ({M}{{H}2}/M *) is consistent with earlier measurements of main-sequence galaxies at these redshifts, and again shows large variations among sources. In some cases, we also measure dust continuum emission. On average, the dust-based estimates of the molecular gas are a factor ˜2-5× smaller than those based on CO. When we account for detections as well as non-detections, we find large diversity in the molecular gas properties of the high-redshift galaxies covered by ASPECS.

  15. Selecting superluminous supernovae in faint galaxies from the first year of the Pan-STARRS1 Medium Deep Survey

    NASA Astrophysics Data System (ADS)

    McCrum, M.; Smartt, S. J.; Rest, A.; Smith, K.; Kotak, R.; Rodney, S. A.; Young, D. R.; Chornock, R.; Berger, E.; Foley, R. J.; Fraser, M.; Wright, D.; Scolnic, D.; Tonry, J. L.; Urata, Y.; Huang, K.; Pastorello, A.; Botticella, M. T.; Valenti, S.; Mattila, S.; Kankare, E.; Farrow, D. J.; Huber, M. E.; Stubbs, C. W.; Kirshner, R. P.; Bresolin, F.; Burgett, W. S.; Chambers, K. C.; Draper, P. W.; Flewelling, H.; Jedicke, R.; Kaiser, N.; Magnier, E. A.; Metcalfe, N.; Morgan, J. S.; Price, P. A.; Sweeney, W.; Wainscoat, R. J.; Waters, C.

    2015-04-01

    The Pan-STARRS1 (PS1) survey has obtained imaging in five bands (griz yP1) over 10 Medium Deep Survey (MDS) fields covering a total of 70 square degrees. This paper describes the search for apparently hostless supernovae (SNe) within the first year of PS1 MDS data with an aim of discovering superluminous supernovae (SLSNe). A total of 249 hostless transients were discovered down to a limiting magnitude of MAB ˜ 23.5, of which 76 were classified as Type Ia supernovae (SNe Ia). There were 57 SNe with complete light curves that are likely core-collapse SNe (CCSNe) or type Ic SLSNe and 12 of these have had spectra taken. Of these 12 hostless, non-Type Ia SNe, 7 were SLSNe of type Ic at redshifts between 0.5 and 1.4. This illustrates that the discovery rate of type Ic SLSNe can be maximized by concentrating on hostless transients and removing normal SNe Ia. We present data for two possible SLSNe; PS1-10pm (z = 1.206) and PS1-10ahf (z = 1.1), and estimate the rate of type Ic SLSNe to be between 3^{+3}_{-2}× 10^{-5} and 8^{+2}_{-1}× 10^{-5} that of the CCSN rate within 0.3 ≤ z ≤ 1.4 by applying a Monte Carlo technique. The rate of slowly evolving, type Ic SLSNe (such as SN2007bi) is estimated as a factor of 10 lower than this range.

  16. A Deep Proper Motion Catalog Within the Sloan Digital Sky Survey Footprint. II. The White Dwarf Luminosity Function

    NASA Astrophysics Data System (ADS)

    Munn, Jeffrey A.; Harris, Hugh C.; von Hippel, Ted; Kilic, Mukremin; Liebert, James W.; Williams, Kurtis A.; DeGennaro, Steven; Jeffery, Elizabeth; Dame, Kyra; Gianninas, A.; Brown, Warren R.

    2017-01-01

    A catalog of 8472 white dwarf (WD) candidates is presented, selected using reduced proper motions from the deep proper motion catalog of Munn et al. Candidates are selected in the magnitude range 16< r< 21.5 over 980 square degrees, and 16< r< 21.3 over an additional 1276 square degrees, within the Sloan Digital Sky Survey (SDSS) imaging footprint. Distances, bolometric luminosities, and atmospheric compositions are derived by fitting SDSS ugriz photometry to pure hydrogen and helium model atmospheres (assuming surface gravities {log} {\\text{}}g=8). The disk white dwarf luminosity function (WDLF) is constructed using a sample of 2839 stars with 5.5< {M}{bol}< 17, with statistically significant numbers of stars cooler than the turnover in the luminosity function. The WDLF for the halo is also constructed, using a sample of 135 halo WDs with 5< {M}{bol}< 16. We find space densities of disk and halo WDs in the solar neighborhood of 5.5+/- 0.1× {10}-3 {{pc}}-3 and 3.5+/- 0.7× {10}-5 {{pc}}-3, respectively. We resolve the bump in the disk WDLF due to the onset of fully convective envelopes in WDs, and see indications of it in the halo WDLF as well.

  17. Constraints on the Space Density of Methane Dwarfs and the Substellar Mass Function from a Deep Near-Infrared Survey.

    PubMed

    Herbst; Thompson; Fockenbrock; Rix; Beckwith

    1999-11-20

    We report preliminary results of a deep near-infrared search for methane-absorbing brown dwarfs; almost 5 yr after the discovery of Gl 229b, there are only a few confirmed examples of this type of object. New J-band, wide-field images, combined with preexisting R-band observations, allow efficient identification of candidates by their extreme (R-J) colors. Follow-up measurements with custom filters can then confirm objects with methane absorption. To date, we have surveyed a total of 11.4 deg2 to J approximately 20.5 and R approximately 25. Follow-up CH4 filter observations of promising candidates in one-fourth of these fields have turned up no methane-absorbing brown dwarfs. With 90% confidence, this implies that the space density of objects similar to Gl 229b is less than 0.012 pc-3. These calculations account for the vertical structure of the Galaxy, which can be important for sensitive measurements. Combining published theoretical atmospheric models with our observations sets an upper limit of alpha

  18. Spectroscopic identification of a redshift 1.55 supernova host galaxy from the Subaru Deep Field Supernova Survey

    NASA Astrophysics Data System (ADS)

    Frederiksen, Teddy F.; Graur, Or; Hjorth, Jens; Maoz, Dan; Poznanski, Dovi

    2014-03-01

    Context. The Subaru Deep Field (SDF) Supernova Survey discovered ten Type Ia supernovae (SNe Ia) in the redshift range 1.5 < z < 2.0, determined solely from photometric redshifts of the host galaxies. However, photometric redshifts might be biased, and the SN sample could be contaminated by active galactic nuclei (AGNs). Aims: We aim to obtain the first robust redshift measurement and classification of a z > 1.5 SDF SN Ia host galaxy candidate. Methods: We use the X-shooter (U-to-K-band) spectrograph on the Very Large Telescope to allow the detection of different emission lines in a wide spectral range. Results: We measure a spectroscopic redshift of 1.54563 ± 0.00027 of hSDF0705.25, consistent with its photometric redshift of 1.552 ± 0.018. From the strong emission-line spectrum we rule out AGN activity, thereby confirming the optical transient as a SN. The host galaxy follows the fundamental metallicity relation showing that the properties of this high-redshift SN Ia host galaxy is similar to other field galaxies. Conclusions: Spectroscopic confirmation of additional SDF SN hosts would be required to confirm the cosmic SN rate evolution measured in the SDF. Based on observations made with ESO telescopes at the La Silla Paranal Observatory under program ID 089.A-0739.

  19. A DEEP VERY LARGE ARRAY RADIO CONTINUUM SURVEY OF THE CORE AND OUTSKIRTS OF THE COMA CLUSTER

    SciTech Connect

    Miller, Neal A.; Hornschemeier, Ann E.; Mobasher, Bahram

    2009-05-15

    We present deep 1.4 GHz Very Large Array radio continuum observations of two {approx}0.5 deg{sup 2} fields in the Coma cluster of galaxies. The two fields, 'Coma 1' and 'Coma 3', correspond to the cluster core and southwest infall region and were selected on account of abundant preexisting multiwavelength data. In their most sensitive regions the radio data reach 22 {mu}Jy rms per 4.''4 beam, sufficient to detect (at 5{sigma}) Coma member galaxies with L {sub 1.4{sub G}}{sub Hz} = 1.3 x 10{sup 20} W Hz{sup -1}. The full catalog of radio detections is presented herein and consists of 1030 sources detected at {>=}5{sigma}, 628 of which are within the combined Coma 1 and Coma 3 area. We also provide optical identifications of the radio sources using data from the Sloan Digital Sky Survey. The depth of the radio observations allows us to detect active galactic nucleus in cluster elliptical galaxies with M{sub r} < -20.5 (AB magnitudes), including radio detections for all cluster ellipticals with M{sub r} < -21.8. At fainter optical magnitudes (-20.5 < M{sub r} {approx}< -19), the radio sources are associated with star-forming galaxies with star formation rates as low as 0.1 M {sub sun} yr{sup -1}.

  20. The Host Galaxy Properties of Variability Selected AGN in the Pan-STARRS1 Medium Deep Survey

    NASA Astrophysics Data System (ADS)

    Heinis, S.; Gezari, S.; Kumar, S.; Burgett, W. S.; Flewelling, H.; Huber, M. E.; Kaiser, N.; Wainscoat, R. J.; Waters, C.

    2016-07-01

    We study the properties of 975 active galactic nuclei (AGNs) selected by variability in the Pan-STARRS1 Medium deep Survey. Using complementary multi-wavelength data from the ultraviolet to the far-infrared, we use spectral energy distribution fitting to determine the AGN and host properties at z < 1 and compare to a well-matched control sample. We confirm the trend previously observed: that the variability amplitude decreases with AGN luminosity, but we also observe that the slope of this relation steepens with wavelength, resulting in a “redder when brighter” trend at low luminosities. Our results show that AGNs are hosted by more massive hosts than control sample galaxies, while the rest frame dust-corrected NUV - r color distribution of AGN hosts is similar to control galaxies. We find a positive correlation between the AGN luminosity and star formation rate (SFR), independent of redshift. AGN hosts populate the entire range of SFRs within and outside of the Main Sequence of star-forming galaxies. Comparing the distribution of AGN hosts and control galaxies, we show that AGN hosts are less likely to be hosted by quiescent galaxies and more likely to be hosted by Main Sequence or starburst galaxies.

  1. The Burrell Schmidt Deep Virgo Survey: Tidal Debris, Galaxy Halos, and Diffuse Intracluster Light in the Virgo Cluster

    NASA Astrophysics Data System (ADS)

    Mihos, J. Christopher; Harding, Paul; Feldmeier, John J.; Rudick, Craig; Janowiecki, Steven; Morrison, Heather; Slater, Colin; Watkins, Aaron

    2017-01-01

    We present the results of a deep imaging survey of the Virgo cluster of galaxies, concentrated around the cores of Virgo subclusters A and B. The goal of this survey was to detect and study very low surface brightness features present in Virgo, including discrete tidal features, the faint halos of luminous galaxies, and the diffuse intracluster light (ICL). Our observations span roughly 16 degrees2 in two filters, reaching a 3σ limiting depth of {μ }B = 29.5 and {μ }V = 28.5 mag arcsec-2. At these depths, our limiting systematic uncertainties are astrophysical: variations in faint background sources as well as scattered light from galactic dust. We show that this dust-scattered light is well traced by deep far-infrared imaging, making it possible to separate it from true diffuse light in Virgo. We use our imaging to trace and measure the color of the diffuse tidal streams and ICL in the Virgo core near M87, in fields adjacent to the core including the M86/M84 region, and to the south of the core around M49 and subcluster B, along with the more distant W{}\\prime cloud around NGC 4365. Overall, the bulk of the projected ICL is found in the Virgo core and within the W{}\\prime cloud; we find little evidence for an extensive ICL component in the field around M49. The bulk of the ICL we detect is fairly red in color (B - V = 0.7-0.9), indicative of old, evolved stellar populations. Based on the luminosity of the observed ICL features in the cluster, we estimate a total Virgo ICL fraction of 7%-15%. This value is somewhat smaller than that expected for massive, evolved clusters, suggesting that Virgo is still in the process of growing its extended ICL component. We also trace the shape of M87's extremely boxy outer halo out to ˜150 kpc, and show that the current tidal stripping rate from low luminosity galaxies is insufficient to have built M87's outer halo over a Hubble time. We identify a number of previously unknown low surface brightness structures around

  2. Internal Color Properties of Resolved Spheroids in the Deep Hubble Space Telescope Advanced Camera for Surveys Field of UGC 10214

    NASA Astrophysics Data System (ADS)

    Menanteau, F.; Ford, H. C.; Illingworth, G. D.; Sirianni, M.; Blakeslee, J. P.; Meurer, G. R.; Martel, A. R.; Benítez, N.; Postman, M.; Franx, M.; Ardila, D. R.; Bartko, F.; Bouwens, R. J.; Broadhurst, T. J.; Brown, R. A.; Burrows, C. J.; Cheng, E. S.; Clampin, M.; Cross, N. J. G.; Feldman, P. D.; Golimowski, D. A.; Gronwall, C.; Hartig, G. F.; Infante, L.; Kimble, R. A.; Krist, J. E.; Lesser, M. P.; Miley, G. K.; Rosati, P.; Sparks, W. B.; Tran, H. D.; Tsvetanov, Z. I.; White, R. L.; Zheng, W.

    2004-09-01

    We study the internal color properties of a morphologically selected sample of spheroidal galaxies taken from the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) Early Release Observation program of UGC 10214 (``the Tadpole''). By taking advantage of the unprecedented high resolution of the ACS in this very deep data set, we are able to characterize spheroids at subarcsecond scales. Using the V606 and I814 bands, we construct V-I color maps and extract color gradients for a sample of spheroids at I814<24 mag. We assess the ability of the ACS to make resolved color studies of galaxies by comparing its results with the multicolor data from the Hubble Deep Fields (HDFs). Here we report that with ACS WFC data using less than ~1/10 the exposure of the WFPC2 HDFs, it is possible to confidently carry out resolved studies of faint galaxies at similar magnitude limits. We also investigate the existence of a population of morphologically classified spheroids that show extreme variation in their internal color properties, similar to the ones reported in the HDFs. These are displayed as blue cores and inverse color gradients with respect to those accounted for from metallicity variations. Following the same analysis, we find a similar fraction of early-type systems (~30%-40%) that show nonhomologous internal colors, suggestive of recent star formation activity. We present two statistics for quantifying the internal color variation in galaxies and tracing blue cores, from which we estimate the ratio of nonhomogeneous to homogeneous internal colors as a function of redshift up to z<~1.2. We find that it can be described as about constant as a function of redshift, with a small increase with redshift for the fraction of spheroids that present strong color dispersions. The implications of a constant fraction at all redshifts suggests the existence of a relatively permanent population of evolving spheroids up to z<~1. We discuss the implications of this in the

  3. A critical analysis of the UV luminosity function at redshift ~7 from deep WFC3 data

    NASA Astrophysics Data System (ADS)

    Grazian, A.; Castellano, M.; Koekemoer, A. M.; Fontana, A.; Pentericci, L.; Testa, V.; Boutsia, K.; Giallongo, E.; Giavalisco, M.; Santini, P.

    2011-08-01

    Context. The study of the luminosity function (LF) of Lyman break galaxies (LBGs) at z = 7 is very important for ascertaining their role in the reionization of the Universe. These galaxies can be used also to investigate in detail the processes of formation and evolution of galactic structures in the infancy of our Universe. Aims: In this work we plan to perform a detailed and critical analysis of the statistical and systematic errors in the z ~ 7 LF determination. Methods: To this aim, we have assembled a large sample of candidate LBGs at z ~ 7 from different surveys, spanning a large variety of areas and depths. In particular, we have combined data from the deep (J < 27.4) and ultradeep (J < 29.2) surveys recently acquired with the new WFC3 NIR camera on HST, over the GOODS-ERS (~40 sq. arcmin) and the HUDF (~4 sq. arcmin) fields, with ground based surveys in wide and shallow areas from Hawk-I@VLT and HyperSuprimecam@Subaru. We have used public ACS images in the z band to select z-dropout galaxies, and other public data both in the blue (BVI) and in the red bands to reject possible low-redshift interlopers. We have compared our results with extensive Monte Carlo simulations to quantify the observational effects of our selection criteria as well as the effects of photometric scatter, color selections or the morphology of the candidates. Results: We have found that the number density of faint LBGs at z ~ 7 is only marginally sensitive to the color selection adopted, but it is strongly dependent from the assumption made on the half light distributions of the simulated galaxies, used to correct the observed sample for incompleteness. The slope of the faint end of the LBGs LF has thus a rather large uncertainty, due to the unknown distribution of physical sizes of the z ~ 7 LBGs. The implications of these uncertainties have been neglected by previous works. Conclusions: We conclude that galaxies at z ~ 7 are unable to reionize the Universe unless there is a

  4. OT2_sserje01_2: THE HERSCHEL-AKARI NEP DEEP SURVEY: the cosmological history of stellar mass assembly and black hole accretion

    NASA Astrophysics Data System (ADS)

    Serjeant, S.

    2011-09-01

    We propose a far-IR and submm mapping survey of the premier AKARI deep field in the North Ecliptic Pole, in PACS/SPIRE parallel mode. This is the only major deep infrared field not yet covered by Herschel guaranteed or open time key projects. The outstanding and unparalleled continuous mid-IR photometric coverage from AKARI, far better than equivalent Spitzer surveys, enables a wide range of galaxy evolution diagnostics unachievable in any other survey field (including Herschel HerMES/PEP fields), by spanning the wavelengths of redshifted PAH and silicate features and the peak energy output of AGN dust tori. The investment by AKARI in the NEP represents ~10 percent of the entire pointed observations available throughout the lifetime of AKARI. Our proposal remedies the remarkable omission from Herschel's legacy surveys of the premier extragalactic deep field from another IR space telescope. We will simultaneously identify and find photometric redshifts for the Herschel point source population, make stacking analysis detections of the galaxies which dominate the submm extragalactic background light as a function of redshift, determine the bolometric power outputs of the galaxies that dominate the submm background, compare the UV/optical/mid-IR continuum/PAH/far-IR/submm/radio star formation rate estimator in the most comprehensive IR survey data set to date, and track the coupled stellar mass assembly and black hole accretion throughout most of the history of the Universe. In OT1 the HOTAC concluded "The science output from the proposed survey will be outstanding [...] The panel was convinced that these observations should be done" but it since became clear that priority 2 time is very unlikely to be executed, so we request reclassification to priority 1.

  5. Deep imaging survey of young, nearby austral stars . VLT/NACO near-infrared Lyot-coronographic observations

    NASA Astrophysics Data System (ADS)

    Chauvin, G.; Lagrange, A.-M.; Bonavita, M.; Zuckerman, B.; Dumas, C.; Bessell, M. S.; Beuzit, J.-L.; Bonnefoy, M.; Desidera, S.; Farihi, J.; Lowrance, P.; Mouillet, D.; Song, I.

    2010-01-01

    Context. High contrast and high angular resolution imaging is the optimal search technique for substellar companions to nearby stars at physical separations larger than typically 10 AU. Two distinct populations of substellar companions, brown dwarfs and planets, can be probed and characterized. As a result, fossile traces of processes of formation and evolution can be revealed by physical and orbital properties, both for individual systems and as an ensemble. Aims: Since November 2002, we have conducted a large, deep imaging, survey of young, nearby associations of the southern hemisphere. Our goal is detection and characterization of substellar companions with projected separations in the range 10-500 AU. We have observed a sample of 88 stars, primarily G to M dwarfs, younger than 100 Myr, and within 100 pc of Earth. Methods: The VLT/NACO adaptive optics instrument of the ESO Paranal Observatory was used to explore the faint circumstellar environment between typically 0.1 and 10''. Diffraction-limited observations in H and K_s-band combined with Lyot-coronagraphy enabled us to reach primary star-companion brightness ratios as small as 10-6. The existence of planetary mass companions could therefore be probed. We used a standardized observing sequence to precisely measure the position and flux of all detected sources relative to their visual primary star. Repeated observations at several epochs enabled us to discriminate comoving companions from background objects. Results: We report the discovery of 17 new close (0.1-5.0'') multiple systems. HIP 108195 AB and C (F1 III-M6), HIP 84642 AB (a~14 AU, K0-M5) and TWA22 AB (a~1.8 AU; M6-M6) are confirmed comoving systems. TWA22 AB is likely to be a rare astrometric calibrator that can be used to test evolutionary model predictions. Among our complete sample, a total of 65 targets were observed with deep coronagraphic imaging. About 240 faint companion candidates were detected around 36 stars. Follow-up observations with

  6. Combining resources to obtain a comprehensive survey of the bovine embryo transcriptome through deep sequencing and microarrays.

    PubMed

    Robert, Claude; Nieminen, Julie; Dufort, Isabelle; Gagné, Dominic; Grant, Jason R; Cagnone, Gaël; Plourde, Dany; Nivet, Anne-Laure; Fournier, Éric; Paquet, Éric; Blazejczyk, Michal; Rigault, Philippe; Juge, Nicolas; Sirard, Marc-André

    2011-09-01

    While most assisted reproductive technologies (ART) are considered routine for the reproduction of species of economical importance, such as the bovine, the impact of these manipulations on the developing embryo remains largely unknown. In an effort to obtain a comprehensive survey of the bovine embryo transcriptome and how it is modified by ART, resources were combined to design an embryo-specific microarray. Close to one million high-quality reads were produced from subtracted bovine embryo libraries using Roche 454 Titanium deep sequencing technology, which enabled the creation of an augmented bovine genome catalog. This catalog was enriched with bovine embryo transcripts, and included newly discovered indel type and 3'UTR variants. Using this augmented bovine genome catalog, the EmbryoGENE Bovine Microarray was designed and is composed of a total of 42,242 probes, including 21,139 known reference genes; 9,322 probes for novel transcribed regions (NTRs); 3,677 alternatively spliced exons; 3,353 3'-tiling probes; and 3,723 controls. A suite of bioinformatics tools was also developed to facilitate microrarray data analysis and database creation; it includes a quality control module, a Laboratory Information Management System (LIMS) and microarray analysis software. Results obtained during this study have already led to the identification of differentially expressed blastocyst targets, NTRs, splice variants of the indel type, and 3'UTR variants. We were able to confirm microarray results by real-time PCR, indicating that the EmbryoGENE bovine microarray has the power to detect physiologically relevant changes in gene expression. Copyright © 2011 Wiley-Liss, Inc.

  7. NEW MEASUREMENTS OF THE COSMIC INFRARED BACKGROUND FLUCTUATIONS IN DEEP SPITZER/IRAC SURVEY DATA AND THEIR COSMOLOGICAL IMPLICATIONS

    SciTech Connect

    Kashlinsky, A.; Arendt, R. G.; Mather, J.; Moseley, S. H.; Ashby, M. L. N.; Fazio, G. G.

    2012-07-01

    We extend previous measurements of cosmic infrared background (CIB) fluctuations to {approx}< 1 Degree-Sign using new data from the Spitzer Extended Deep Survey. Two fields with depths of {approx_equal} 12 hr pixel{sup -1} over three epochs are analyzed at 3.6 and 4.5 {mu}m. Maps of the fields were assembled using a self-calibration method uniquely suitable for probing faint diffuse backgrounds. Resolved sources were removed from the maps to a magnitude limit of mag{sub AB} {approx_equal} 25, as indicated by the level of the remaining shot noise. The maps were then Fourier transformed and their power spectra were evaluated. Instrumental noise was estimated from the time-differenced data, and subtracting this isolates the spatial fluctuations of the actual sky. The power spectra of the source-subtracted fields remain identical (within the observational uncertainties) for the three epochs indicating that zodiacal light contributes negligibly to the fluctuations. Comparing to 8 {mu}m power spectra shows that Galactic cirrus cannot account for the fluctuations. The signal appears isotropically distributed on the sky as required for an extragalactic origin. The CIB fluctuations continue to diverge to >10 times those of known galaxy populations on angular scales out to {approx}< 1 Degree-Sign . The low shot-noise levels remaining in the diffuse maps indicate that the large-scale fluctuations arise from the spatial clustering of faint sources well below the confusion noise. The spatial spectrum of these fluctuations is in reasonable agreement with an origin in populations clustered according to the standard cosmological model ({Lambda}CDM) at epochs coinciding with the first stars era.

  8. The KMOS Deep Survey (KDS) - I. Dynamical measurements of typical star-forming galaxies at z ≃ 3.5

    NASA Astrophysics Data System (ADS)

    Turner, O. J.; Cirasuolo, M.; Harrison, C. M.; McLure, R. J.; Dunlop, J. S.; Swinbank, A. M.; Johnson, H. L.; Sobral, D.; Matthee, J.; Sharples, R. M.

    2017-10-01

    We present dynamical measurements from the KMOS (K-band multi-object spectrograph) Deep Survey (KDS), which comprises 77 typical star-forming galaxies at z ≃ 3.5 in the mass range 9.0 < log (M⋆/M⊙) < 10.5. These measurements constrain the internal dynamics, the intrinsic velocity dispersions (σint) and rotation velocities (VC) of galaxies in the high-redshift Universe. The mean velocity dispersion of the galaxies in our sample is σ _int = 70.8^{+3.3}_{-3.1} km s^{-1}, revealing that the increasing average σint with increasing redshift, reported for z ≲ 2, continues out to z ≃ 3.5. Only 36 ± 8 per cent of our galaxies are rotation-dominated (VC/σint > 1), with the sample average VC/σint value much smaller than at lower redshift. After carefully selecting comparable star-forming samples at multiple epochs, we find that the rotation-dominated fraction evolves with redshift with a z-0.2 dependence. The rotation-dominated KDS galaxies show no clear offset from the local rotation velocity-stellar mass (i.e. VC-M⋆) relation, although a smaller fraction of the galaxies are on the relation due to the increase in the dispersion-dominated fraction. These observations are consistent with a simple equilibrium model picture, in which random motions are boosted in high-redshift galaxies by a combination of the increasing gas fractions, accretion efficiency, specific star formation rate and stellar feedback and which may provide significant pressure support against gravity on the galactic disc scale.

  9. The ATLAS 5.5 GHz Survey of the Extended Chandra Deep Field South: Source Counts and Spectral Indices

    NASA Astrophysics Data System (ADS)

    Huynh, Minh T.; Hopkins, A. M.; Lenc, E.; Mao, M.; Middelberg, E.; Norris, R.; Randall, K.

    2013-01-01

    Star forming galaxies are thought to dominate the sub-mJy radio population, but recent work has shown that low luminosity AGN can still make a significant contribution to the faint radio source population. We have observed the extended Chandra Deep Field South at 5.5 GHz using a mosaic of 42 pointings with the Australia Telescope Compact Array (ATCA). Our image reaches an almost uniform sensitivity of ~12 μJy rms over 0.25 deg^2 with a restoring beam of 4.9 × 2.0 arcsec, making it one of the deepest 6cm surveys to date. We present the 5.5 GHz source counts from this field. We take advantage of the large amounts of ancillary data in this field to study the 1.4 to 5.5 GHz spectral indices of the sub-mJy population. For the full 5.5 GHz selected sample we find a flat median spectral index, α_med = -0.40, consistent with previous results. However, the spectral index appears to steepen at the faintest flux density levels (S5.5GHz < 0.1 mJy), where α_med = -0.68. We performed stacking analysis of the faint 1.4 GHz selected sample (40 < S1.4GHz < 200 microJy) and also find a steep average spectral index, α = -0.8, consistent with synchrotron emission. We find a weak trend of steepening spectral index with redshift. Several young AGN candidates are identified using spectral indices, suggesting gigahertz peaked spectrum (GPS) sources are as common in the mJy population as they are at Jy levels.

  10. A Deep XMM-Newton Survey of M33: Point-source Catalog, Source Detection, and Characterization of Overlapping Fields

    NASA Astrophysics Data System (ADS)

    Williams, Benjamin F.; Wold, Brian; Haberl, Frank; Garofali, Kristen; Blair, William P.; Gaetz, Terrance J.; Kuntz, K. D.; Long, Knox S.; Pannuti, Thomas G.; Pietsch, Wolfgang; Plucinsky, Paul P.; Winkler, P. Frank

    2015-05-01

    We have obtained a deep 8 field XMM-Newton mosaic of M33 covering the galaxy out to the D25 isophote and beyond to a limiting 0.2-4.5 keV unabsorbed flux of 5 × 10-16 erg cm-2 s-1 (L \\gt 4 × 1034 erg s-1 at the distance of M33). These data allow complete coverage of the galaxy with high sensitivity to soft sources such as diffuse hot gas and supernova remnants (SNRs). Here, we describe the methods we used to identify and characterize 1296 point sources in the 8 fields. We compare our resulting source catalog to the literature, note variable sources, construct hardness ratios, classify soft sources, analyze the source density profile, and measure the X-ray luminosity function (XLF). As a result of the large effective area of XMM-Newton below 1 keV, the survey contains many new soft X-ray sources. The radial source density profile and XLF for the sources suggest that only ˜15% of the 391 bright sources with L \\gt 3.6 × 1035 erg s-1 are likely to be associated with M33, and more than a third of these are known SNRs. The log(N)-log(S) distribution, when corrected for background contamination, is a relatively flat power law with a differential index of 1.5, which suggests that many of the other M33 sources may be high-mass X-ray binaries. Finally, we note the discovery of an interesting new transient X-ray source, which we are unable to classify.

  11. THE BLACK HOLE-BULGE MASS RELATION OF ACTIVE GALACTIC NUCLEI IN THE EXTENDED CHANDRA DEEP FIELD-SOUTH SURVEY

    SciTech Connect

    Schramm, Malte; Silverman, John D.

    2013-04-10

    We present results from a study to determine whether relations-established in the local universe-between the mass of supermassive black holes (SMBHs) and their host galaxies are in place at higher redshifts. We identify a well-constructed sample of 18 X-ray-selected, broad-line active galactic nuclei (AGNs) in the Extended Chandra Deep Field-South Survey with 0.5 < z < 1.2. This redshift range is chosen to ensure that Hubble Space Telescope (HST) imaging is available with at least two filters that bracket the 4000 A break, thus providing reliable stellar mass estimates of the host galaxy by accounting for both young and old stellar populations. We compute single-epoch, virial black hole (BH) masses from optical spectra using the broad Mg II emission line. For essentially all galaxies in our sample, their total stellar mass content agrees remarkably well, given their BH masses, with local relations of inactive galaxies and active SMBHs. We further decompose the total stellar mass into bulge and disk components separately with full knowledge of the HST point-spread function. We find that {approx}80% of the sample is consistent with the local M{sub BH}-M{sub *,{sub Bulge}} relation even with 72% of the host galaxies showing the presence of a disk. In particular, bulge-dominated hosts are more aligned with the local relation than those with prominent disks. We further discuss the possible physical mechanisms that are capable of building up the stellar mass of the bulge from an extended disk of stars over the subsequent 8 Gyr.

  12. The ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: Search for [CII] Line and Dust Emission in 6

    NASA Astrophysics Data System (ADS)

    Aravena, M.; Decarli, R.; Walter, F.; Bouwens, R.; Oesch, P. A.; Carilli, C. L.; Bauer, F. E.; Da Cunha, E.; Daddi, E.; Gónzalez-López, J.; Ivison, R. J.; Riechers, D. A.; Smail, I.; Swinbank, A. M.; Weiss, A.; Anguita, T.; Bacon, R.; Bell, E.; Bertoldi, F.; Cortes, P.; Cox, P.; Hodge, J.; Ibar, E.; Inami, H.; Infante, L.; Karim, A.; Magnelli, B.; Ota, K.; Popping, G.; van der Werf, P.; Wagg, J.; Fudamoto, Y.

    2016-12-01

    We present a search for [C ii] line and dust continuum emission from optical dropout galaxies at z > 6 using ASPECS, our Atacama Large Millimeter submillimeter Array Spectroscopic Survey in the Hubble Ultra-deep Field (UDF). Our observations, which cover the frequency range of 212-272 GHz, encompass approximately the range of 6 < z < 8 for [C ii] line emission and reach a limiting luminosity of L [C ii] ˜ (1.6-2.5) × 108 L ⊙. We identify 14 [C ii] line emitting candidates in this redshift range with significances >4.5σ, two of which correspond to blind detections with no optical counterparts. At this significance level, our statistical analysis shows that about 60% of our candidates are expected to be spurious. For one of our blindly selected [C ii] line candidates, we tentatively detect the CO(6-5) line in our parallel 3 mm line scan. None of the line candidates are individually detected in the 1.2 mm continuum. A stack of all [C ii] candidates results in a tentative detection with S 1.2 mm = 14 ± 5 μJy. This implies a dust-obscured star-formation rate (SFR) of (3 ± 1) M ⊙ yr-1. We find that the two highest-SFR objects have candidate [C ii] lines with luminosities that are consistent with the low-redshift L [C ii] versus SFR relation. The other candidates have significantly higher [C ii] luminosities than expected from their UV-based SFR. At the current sensitivity, it is unclear whether the majority of these sources are intrinsically bright [C ii] emitters, or spurious sources. If only one of our line candidates was real (a scenario greatly favored by our statistical analysis), we find a source density for [C ii] emitters at 6 < z < 8 that is significantly higher than predicted by current models and some extrapolations from galaxies in the local universe.

  13. A survey of fishes associated with Hawaiian deep-water Halimeda kanaloana (Bryopsidales: Halimedaceae) and Avrainvillea sp. (Bryopsidales: Udoteaceae) meadows

    PubMed Central

    Spalding, Heather L.

    2017-01-01

    The invasive macroalgal species Avrainvillea sp. and native species Halimeda kanaloana form expansive meadows that extend to depths of 80 m or more in the waters off of O‘ahu and Maui, respectively. Despite their wide depth distribution, comparatively little is known about the biota associated with these macroalgal species. Our primary goals were to provide baseline information on the fish fauna associated with these deep-water macroalgal meadows and to compare the abundance and diversity of fishes between the meadow interior and sandy perimeters. Because both species form structurally complex three-dimensional canopies, we hypothesized that they would support a greater abundance and diversity of fishes when compared to surrounding sandy areas. We surveyed the fish fauna associated with these meadows using visual surveys and collections made with clove-oil anesthetic. Using these techniques, we recorded a total of 49 species from 25 families for H. kanaloana meadows and surrounding sandy areas, and 28 species from 19 families for Avrainvillea sp. habitats. Percent endemism was 28.6% and 10.7%, respectively. Wrasses (Family Labridae) were the most speciose taxon in both habitats (11 and six species, respectively), followed by gobies for H. kanaloana (six species). The wrasse Oxycheilinus bimaculatus and cardinalfish Apogonichthys perdix were the most frequently-occurring species within the H. kanaloana and Avrainvillea canopies, respectively. Obligate herbivores and food-fish species were rare in both habitats. Surprisingly, the density and abundance of small epibenthic fishes were greater in open sand than in the meadow canopy. In addition, species richness was also higher in open sand for Avrainvillea sp. We hypothesize that the dense holdfasts and rhizoids present within the meadow canopy may impede benthic-dwelling or bioturbator species, which accounted for 86% and 57% of individuals collected in sand adjacent to H. kanaloana and Avrainvillea sp. habitats

  14. The VIMOS VLT deep survey. The ultraviolet galaxy luminosity function and luminosity density at 3 ≤ z ≤ 4

    NASA Astrophysics Data System (ADS)

    Paltani, S.; Le Fèvre, O.; Ilbert, O.; Arnouts, S.; Bardelli, S.; Tresse, L.; Zamorani, G.; Zucca, E.; Bottini, D.; Garilli, B.; Le Brun, V.; Maccagni, D.; Picat, J.-P.; Scaramella, R.; Scodeggio, M.; Vettolani, G.; Zanichelli, A.; Adami, C.; Bolzonella, M.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Iovino, A.; McCracken, H. J.; Marano, B.; Marinoni, C.; Mazure, A.; Meneux, B.; Merighi, R.; Pellò, R.; Pollo, A.; Pozzetti, L.; Radovich, M.; Bondi, M.; Bongiorno, A.; Brinchmann, J.; Cucciati, O.; de la Torre, S.; Lamareille, F.; Mellier, Y.; Merluzzi, P.; Temporin, S.; Vergani, D.; Walcher, C. J.

    2007-03-01

    Aims:We study the luminosity function of the high-redshift galaxy population with redshifts 3≤ z ≤ 4 using a purely I-band magnitude-selected spectroscopic sample obtained in the framework of the VIMOS VLT Deep Survey (VVDS). Methods: We determine the luminosity function from the VVDS, taking care to add as few assumptions and as simple corrections as possible, and compare our results with those obtained from photometric studies, based on Lyman-break selections or photometric-redshift measurements. Results: We find that in the redshift range 3≤ z ≤ 4, the VVDS luminosity function is parameterized by φ^*=1.24+0.48-0.50×10-3 mag-1 Mpc-3 and M^*=-21.49+0.19-0.19, assuming a slope α=-1.4 consistent with most previous studies. While φ* is comparable to previously found values, M* is significantly brighter by about 0.5 mag at least. Using the conservative slope α=-1.4, we find a luminosity density at 1700 Å L1700(M<-18.5)=2.4×1019 W Mpc-3 and L1700Total=3.1×1019 W Mpc-3, comparable to that estimated in other studies. Conclusions: .The unexpectedly large number of very bright galaxies found in the VVDS indicates that the color-selection and photometric-redshift techniques that are generally used to build high-redshift galaxy samples may be affected by a significant fraction of color-measurement failures or by incomplete modelling of the mix of stellar emission, AGN contribution, dust absorption and intergalactic extinction assumed to identify high-redshift galaxies, making pure magnitude selection better able to trace the full population. Because of the difficulty to identify all low-luminosity galaxies in a spectroscopic survey, the luminosity density could still be significantly underestimated. We also find that the relative contribution of the most luminous galaxies compared to the fainter ones is at least twice as large in the VVDS compared to former estimates. Therefore, the VVDS paints a quite different picture of the role of the most actively star

  15. The VIMOS-VLT Deep Survey. The evolution of galaxy clustering per spectral type to z ≃ 1.5

    NASA Astrophysics Data System (ADS)

    Meneux, B.; Le Fèvre, O.; Guzzo, L.; Pollo, A.; Cappi, A.; Ilbert, O.; Iovino, A.; Marinoni, C.; McCracken, H. J.; Bottini, D.; Garilli, B.; Le Brun, V.; Maccagni, D.; Picat, J. P.; Scaramella, R.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnouts, S.; Arnaboldi, M.; Bardelli, S.; Bolzonella, M.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Marano, B.; Mazure, A.; Merighi, R.; Paltani, S.; Pellò, R.; Pozzetti, L.; Radovich, M.; Zamorani, G.; Zucca, E.; Bondi, M.; Bongiorno, A.; Busarello, G.; Cucciati, O.; Gregorini, L.; Lamareille, F.; Mathez, G.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2006-06-01

    We measure the evolution of clustering for galaxies with different spectral types from 6495 galaxies with 17.5 ≤ IAB ≤ 24 and measured spectroscopic redshifts in the first epoch VIMOS-VLT Deep Survey (VVDS). We divide our sample into four classes, based on the fit of well-defined galaxy spectral energy distributions on observed multi-color data. We measure the projected correlation function w_p(r_p) and estimate the best-fit parameters for a power-law real-space correlation function ξ(r) = (r/r_0)-γ. We find the clustering of early-spectral-type galaxies to be markedly stronger than that of late-type galaxies at all redshifts up to z≃1.2. At z˜ 0.8 , early-type galaxies display a correlation length r_0=4.8 ±0.9 h-1 Mpc, while late types have r_0=2.5 ± 0.4 h-1 Mpc. For the latest class of star-forming blue galaxies, we are able to push our clustering measurement to an effective redshift z˜ 1.4, for luminous galaxies (M_B(AB)≃ -21). The clustering of these objects increases up to r_0=3.42 ± 0.7 h-1 Mpc for z=[1.2,2.0]. The relative bias between early- and late-type galaxies within our magnitude-limited survey remains approximately constant with b=1.6 ± 0.3 from z=0 to z=1.2. This result is in agrement with the local findings and fairly robust against different way of classifying red and blue galaxies. When compared to the expected linear growth of mass fluctuations, a natural interpretation of these observations is that: (a) the assembly of massive early type galaxies is already mostly complete in the densest dark matter halos at z≃1; (b) luminous late-type galaxies are located in higher-density, more clustered regions of the Universe at z≃1.5 than their local low luminous counterpart, indicating that star formation activity is progressively increasing, going back in time, in the higher-density peaks that today are mostly dominated by old galaxies.

  16. The VIMOS-VLT deep survey. Color bimodality and the mix of galaxy populations up to z ~ 2

    NASA Astrophysics Data System (ADS)

    Franzetti, P.; Scodeggio, M.; Garilli, B.; Vergani, D.; Maccagni, D.; Guzzo, L.; Tresse, L.; Ilbert, O.; Lamareille, F.; Contini, T.; Le Fèvre, O.; Zamorani, G.; Brinchmann, J.; Charlot, S.; Bottini, D.; Le Brun, V.; Picat, J. P.; Scaramella, R.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Cappi, A.; Ciliegi, P.; Foucaud, S.; Gavignaud, I.; Iovino, A.; McCracken, H. J.; Marano, B.; Marinoni, C.; Mazure, A.; Meneux, B.; Merighi, R.; Paltani, S.; Pellò, R.; Pollo, A.; Pozzetti, L.; Radovich, M.; Zucca, E.; Cucciati, O.; Walcher, C. J.

    2007-04-01

    Aims: In this paper we discuss the mix of star-forming and passive galaxies up to z ~ 2, based on the first epoch VIMOS-VLT Deep Survey (VVDS) data. Methods: We compute rest-frame magnitudes and colors and analyse the color-magnitude relation and the color distributions. We also use the multi-band VVDS photometric data and spectral templates fitting to derive multi-color galaxy types. Using our spectroscopic dataset we separate galaxies based on a star-formation activity indicator derived combining the equivalent width of the [OII] emission line and the strength of the D_n(4000) continuum break. Results: In agreement with previous works we find that the global galaxy rest-frame color distribution follows a bimodal distribution at z ≤ 1, and we establish that this bimodality holds up to at least z=1.5. The details of the rest-frame color distribution depend however on redshift and on galaxy luminosity, with faint galaxies being bluer than the luminous ones over the whole redshift range covered by our data, and with galaxies becoming bluer as redshift increases. This latter blueing trend does not depend, to a first approximation, on galaxy luminosity. The comparison between the spectral classification and the rest-frame colors shows that about 35-40% of the red objects are in fact star forming galaxies. Hence we conclude that the red sequence cannot be used to effectively isolate a sample of purely passively evolving objects within a cosmological survey. We show how multi-color galaxy types have a slightly higher efficiency than rest-frame color in isolating the passive, non star-forming galaxies within the VVDS sample. Connected to these results is also the finding that the color-magnitude relations derived for the color and for the spectroscopically selected early-type galaxies have remarkably similar properties, with the contaminating star-forming galaxies within the red sequence objects introducing no significant offset in the rest frame colors. Therefore the

  17. First results from the VIMOS/VLT Deep Survey (VVDS): luminosity functions from z˜0 to z˜1.5

    NASA Astrophysics Data System (ADS)

    Zucca, E.; Ilbert, O.; Tresse, L.; Bardelli, S.; Arnouts, S.; Zamorani, G.; Le Fèvre, O.; Vettolani, G.; Adami, C.; sBolzonella, M.; Bondi, M.; Bongiorno, A.; Bottini, D.; Busarello, G.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Garilli, B.; Gavignaud, I.; Gregorini, L.; Guzzo, L.; Iovino, A.; Le Brun, V.; Maccagni, D.; Marano, B.; Marinoni, C.; Mathez, G.; Mazure, A.; McCracken, H. J.; Mellier, Y.; Meneux, B.; Merighi, R.; Merluzzi, P.; Paltani, S.; Pellò, R.; Picat, J. P.; Pollo, A.; Pozzetti, L.; Radovich, M.; Ripepi, V.; Rizzo, D.; Scaramella, R.; Scodeggio, M.; Zanichelli, A.

    The VIMOS/VLT Deep Survey (VVDS) is an on-going program to map the evolution of galaxies, large scale structures and AGNs from the redshift measurement of more than 100000 objects down to a magnitude IAB=24, in combination with a multi-wavelength dataset from radio to X-rays. We present here the results obtained from the first epoch data, regarding in particular the evolution of the luminosity function.

  18. WINGS: A WIde-field Nearby Galaxy-cluster Survey. II. Deep optical photometry of 77 nearby clusters

    NASA Astrophysics Data System (ADS)

    Varela, J.; D'Onofrio, M.; Marmo, C.; Fasano, G.; Bettoni, D.; Cava, A.; Couch, W. J.; Dressler, A.; Kjærgaard, P.; Moles, M.; Pignatelli, E.; Poggianti, B. M.; Valentinuzzi, T.

    2009-04-01

    Context: This is the second paper of a series devoted to the WIde Field Nearby Galaxy-cluster Survey (WINGS). WINGS is a long term project which is gathering wide-field, multi-band imaging and spectroscopy of galaxies in a complete sample of 77 X-ray selected, nearby clusters (0.04 < z < 0.07) located far from the galactic plane (|b|≥ 20°). The main goal of this project is to establish a local reference for evolutionary studies of galaxies and galaxy clusters. Aims: This paper presents the optical (B,V) photometric catalogs of the WINGS sample and describes the procedures followed to construct them. We have paid special care to correctly treat the large extended galaxies (which includes the brightest cluster galaxies) and the reduction of the influence of the bright halos of very bright stars. Methods: We have constructed photometric catalogs based on wide-field images in B and V bands using SExtractor. Photometry has been performed on images in which large galaxies and halos of bright stars were removed after modeling them with elliptical isophotes. Results: We publish deep optical photometric catalogs (90% complete at V ~ 21.7, which translates to ˜ M^*_V+6 at mean redshift), giving positions, geometrical parameters, and several total and aperture magnitudes for all the objects detected. For each field we have produced three catalogs containing galaxies, stars and objects of “unknown” classification (~6%). From simulations we found that the uncertainty of our photometry is quite dependent of the light profile of the objects with stars having the most robust photometry and de Vaucouleurs profiles showing higher uncertainties and also an additional bias of ~-0.2^m. The star/galaxy classification of the bright objects (V < 20) was checked visually making negligible the fraction of misclassified objects. For fainter objects, we found that simulations do not provide reliable estimates of the possible misclassification and therefore we have compared our data

  19. LUMINOUS AND HIGH STELLAR MASS CANDIDATE GALAXIES AT z Almost-Equal-To 8 DISCOVERED IN THE COSMIC ASSEMBLY NEAR-INFRARED DEEP EXTRAGALACTIC LEGACY SURVEY

    SciTech Connect

    Yan Haojing; Finkelstein, Steven L.; Huang, Kuang-Han; Ryan, Russell E.; Ferguson, Henry C.; Koekemoer, Anton M.; Grogin, Norman A.; Dickinson, Mark; Newman, Jeffrey A.; Somerville, Rachel S.; Dave, Romeel; Faber, S. M.; Guo Yicheng; Giavalisco, Mauro; Lee, Kyoung-soo; Reddy, Naveen; Siana, Brian D.; Cooray, Asantha R.; Hathi, Nimish P.; and others

    2012-12-20

    One key goal of the Hubble Space Telescope Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey is to track galaxy evolution back to z Almost-Equal-To 8. Its two-tiered ''wide and deep'' strategy bridges significant gaps in existing near-infrared surveys. Here we report on z Almost-Equal-To 8 galaxy candidates selected as F105W-band dropouts in one of its deep fields, which covers 50.1 arcmin{sup 2} to 4 ks depth in each of three near-infrared bands in the Great Observatories Origins Deep Survey southern field. Two of our candidates have J < 26.2 mag, and are >1 mag brighter than any previously known F105W-dropouts. We derive constraints on the bright end of the rest-frame ultraviolet luminosity function of galaxies at z Almost-Equal-To 8, and show that the number density of such very bright objects is higher than expected from the previous Schechter luminosity function estimates at this redshift. Another two candidates are securely detected in Spitzer Infrared Array Camera images, which are the first such individual detections at z Almost-Equal-To 8. Their derived stellar masses are on the order of a few Multiplication-Sign 10{sup 9} M{sub Sun }, from which we obtain the first measurement of the high-mass end of the galaxy stellar mass function at z Almost-Equal-To 8. The high number density of very luminous and very massive galaxies at z Almost-Equal-To 8, if real, could imply a large stellar-to-halo mass ratio and an efficient conversion of baryons to stars at such an early time.

  20. VIMOS Ultra-Deep Survey (VUDS): Witnessing the assembly of a massive cluster at z ~ 3.3

    NASA Astrophysics Data System (ADS)

    Lemaux, B. C.; Cucciati, O.; Tasca, L. A. M.; Le Fèvre, O.; Zamorani, G.; Cassata, P.; Garilli, B.; Le Brun, V.; Maccagni, D.; Pentericci, L.; Thomas, R.; Vanzella, E.; Zucca, E.; Amorín, R.; Bardelli, S.; Capak, P.; Cassarà, L. P.; Castellano, M.; Cimatti, A.; Cuby, J. G.; de la Torre, S.; Durkalec, A.; Fontana, A.; Giavalisco, M.; Grazian, A.; Hathi, N. P.; Ilbert, O.; Moreau, C.; Paltani, S.; Ribeiro, B.; Salvato, M.; Schaerer, D.; Scodeggio, M.; Sommariva, V.; Talia, M.; Taniguchi, Y.; Tresse, L.; Vergani, D.; Wang, P. W.; Charlot, S.; Contini, T.; Fotopoulou, S.; Gal, R. R.; Kocevski, D. D.; López-Sanjuan, C.; Lubin, L. M.; Mellier, Y.; Sadibekova, T.; Scoville, N.

    2014-12-01

    Using new spectroscopic observations obtained as part of the VIMOS Ultra-Deep Survey (VUDS), we performed a systematic search for overdense environments in the early universe (z> 2) and report here on the discovery of Cl J0227-0421, a massive protocluster at z = 3.29. This protocluster is characterized by both the large overdensity of spectroscopically confirmed members, δgal = 10.5 ± 2.8, and a significant overdensity in photometric redshift members. The halo mass of this protocluster is estimated by a variety of methods to be ~3 × 1014ℳ⊙ at z ~ 3.3, which, evolved to z = 0 results in a halo mass rivaling or exceeding that of the Coma cluster. The properties of 19 spectroscopically confirmed member galaxies are compared with a large sample of VUDS/VVDS galaxies in lower density field environments at similar redshifts. We find tentative evidence for an excess of redder, brighter, and more massive galaxies within the confines of the protocluster relative to the field population, which suggests that we may be observing the beginning ofenvironmentally induced quenching. The properties of these galaxies are investigated, including a discussion of the brightest protocluster galaxy, which appears to be undergoing vigorous coeval nuclear and starburst activity. The remaining member galaxies appear to have characteristics that are largely similar to the field population. Though we find weaker evidence of the suppression of the median star formation rates among and differences in the stacked spectra of member galaxies with respect to the field, we defer any conclusions about these trends to future work with the ensemble of protostructures that are found in the full VUDS sample. Based on data obtained with the European Southern Observatory Very Large Telescope, Paranal, Chile, under Large Program 185.A-0791.Appendices are available in electronic form at http://www.aanda.orgData are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130

  1. A Deep Hubble Space Telescope H-Band Imaging Survey of Massive Gas-Rich Mergers. II. The QUEST QSOs

    NASA Astrophysics Data System (ADS)

    Veilleux, S.; Kim, D.-C.; Rupke, D. S. N.; Peng, C. Y.; Tacconi, L. J.; Genzel, R.; Lutz, D.; Sturm, E.; Contursi, A.; Schweitzer, M.; Dasyra, K. M.; Ho, L. C.; Sanders, D. B.; Burkert, A.

    2009-08-01

    We report the results from a deep Hubble Space Telescope (HST) NICMOS H-band imaging survey of 28 z < 0.3 QSOs from the Palomar-Green (PG) sample. This program is part of QUEST (Quasar/ULIRG Evolution Study) and complements a similar set of data on 26 highly nucleated ULIRGs presented in Paper I. Our analysis indicates that the fraction of QSOs with elliptical hosts is higher among QSOs with undetected far-infrared (FIR) emission, small infrared excess (L IR/L B < 10), and luminous hosts. The hosts of FIR-faint QSOs show a tendency to have less pronounced merger-induced morphological anomalies and larger QSO-to-host luminosity ratios on average than the hosts of FIR-bright QSOs, consistent with late-merger evolution from FIR-bright to FIR-faint QSOs. The spheroid sizes (~ 0.3-5.5 kpc) and total host luminosities (~ 0.6-7.2 L* H ) of the radio-quiet PG QSOs in our sample are statistically indistinguishable from the ULIRG hosts presented in Paper I, while those of radio-loud PG QSOs are systematically larger and more luminous. ULIRGs and PG QSOs with elliptical hosts fall near, but not exactly on, the fundamental plane of inactive spheroids. We confirm the systematic trend noted in Paper I for objects with small (lsim 2 kpc) spheroids to be up to ~ 1 mag brighter than inactive spheroids. The host colors and wavelength dependence of their sizes support the idea that these deviations are at least in part due to non-nuclear star formation. However, the amplitudes of these deviations depend mainly on host sizes, and possibly on infrared excess, but not on merger phase, QSO-to-host luminosity ratio, optical spectral type, active galactic nucleus fractional contribution to the bolometric luminosity, or host R - H color. Taken at face value (i.e., no correction for extinction or the presence of a young stellar population), the H-band spheroid-host luminosities imply black hole masses ~ (5-200) × 107 M sun and sub-Eddington mass accretion rates for both QSOs and ULIRGs

  2. Size evolution of star-forming galaxies with 2 Deep Survey

    NASA Astrophysics Data System (ADS)

    Ribeiro, B.; Le Fèvre, O.; Tasca, L. A. M.; Lemaux, B. C.; Cassata, P.; Garilli, B.; Maccagni, D.; Zamorani, G.; Zucca, E.; Amorín, R.; Bardelli, S.; Fontana, A.; Giavalisco, M.; Hathi, N. P.; Koekemoer, A.; Pforr, J.; Tresse, L.; Dunlop, J.

    2016-08-01

    Context. The size of a galaxy encapsulates the signature of the different physical processes driving its evolution. The distribution of galaxy sizes in the Universe as a function of cosmic time is therefore a key to understand galaxy evolution. Aims: We aim to measure the average sizes and size distributions of galaxies as they are assembling before the peak in the comoving star formation rate density of the Universe to better understand the evolution of galaxies across cosmic time. Methods: We used a sample of ~1200 galaxies in the COSMOS and ECDFS fields with confirmed spectroscopic redshifts 2 ≤ zspec ≤ 4.5 in the VIMOS Ultra Deep Survey (VUDS), representative of star-forming galaxies with iAB ≤ 25. We first derived galaxy sizes by applying a classical parametric profile-fitting method using GALFIT. We then measured the total pixel area covered by a galaxy above a given surface brightness threshold, which overcomes the difficulty of measuring sizes of galaxies with irregular shapes. We then compared the results obtained for the equivalent circularized radius enclosing 100% of the measured galaxy light r100T ~2.2 to those obtained with the effective radius re,circ measured with GALFIT. Results: We find that the sizes of galaxies computed with our non-parametric approach span a wide range but remain roughly constant on average with a median value r100T ~2.2 kpc for galaxies with 2

  3. WINGS: a WIde-field nearby Galaxy-cluster survey. III. Deep near-infrared photometry of 28 nearby clusters

    NASA Astrophysics Data System (ADS)

    Valentinuzzi, T.; Woods, D.; Fasano, G.; Riello, M.; D'Onofrio, M.; Varela, J.; Bettoni, D.; Cava, A.; Couch, W. J.; Dressler, A.; Fritz, J.; Moles, M.; Omizzolo, A.; Poggianti, B. M.; Kjærgaard, P.

    2009-07-01

    Context: This is the third paper in a series devoted to the WIde-field Nearby Galaxy-cluster Survey (WINGS). WINGS is a long-term project aimed at gathering wide-field, multiband imaging and spectroscopy of galaxies in a complete sample of 77 X-ray selected, nearby clusters (0.04deep near-infrared photometric catalogs (90% complete in detection rate at total magnitudes J≈ 20.5, K≈ 19.4, and in classification rate at J≈19.5 and K≈ 18.5), giving positions, geometrical parameters, total and aperture magnitudes for all detected sources. For each field we classify the detected sources as stars, galaxies, and objects of “unknown” nature. Based on observations taken at the United Kingdom Infra-Red Telescope, operated by the Joint Astronomy Centre on behalf of the Science and Technology Facilities Council of the UK. J and K photometric catalogs are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/501/851

  4. New Measurements of the Cosmic Infrared Background Fluctuations in Deep SpitzerllRAC Survey Data and their Cosmological Implications

    NASA Technical Reports Server (NTRS)

    Kashlinsky, A.; Arendt, R. G.; Ashby, M. L. N.; Fazio, G. G.; Mather, J.; Moseley, S. H.

    2012-01-01

    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

  5. The VIMOS VLT Deep Survey. Evolution of the non-linear galaxy bias up to z = 1.5

    NASA Astrophysics Data System (ADS)

    Marinoni, C.; Le Fèvre, O.; Meneux, B.; Iovino, A.; Pollo, A.; Ilbert, O.; Zamorani, G.; Guzzo, L.; Mazure, A.; Scaramella, R.; Cappi, A.; McCracken, H. J.; Bottini, D.; Garilli, B.; Le Brun, V.; Maccagni, D.; Picat, J. P.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnouts, S.; Bardelli, S.; Blaizot, J.; Bolzonella, M.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Marano, B.; Mathez, G.; Merighi, R.; Paltani, S.; Pellò, R.; Pozzetti, L.; Radovich, M.; Zucca, E.; Bondi, M.; Bongiorno, A.; Busarello, G.; Colombi, S.; Cucciati, O.; Lamareille, F.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2005-11-01

    We present the first measurements of the Probability Distribution Function (PDF) of galaxy fluctuations in the four-passes, first-epoch VIMOS-VLT Deep Survey (VVDS) cone, covering 0.4×0.4 deg between 0.45 h-1Mpc. By subdividing the sample according to galaxy luminosity and colors, we also show that: iv) brighter galaxies are more strongly biased than less luminous ones at every redshift and the dependence of biasing on luminosity at z ˜ 0.8 is in good agreement with what is observed in the local Universe; v) red objects are systematically more biased than blue objects at all cosmic

  6. First Results from the 7 Ms Chandra Deep Field-South Survey: A Good Hard Look at Growing Supermassive Black Holes in the Distant Universe

    NASA Astrophysics Data System (ADS)

    Brandt, William; Chandra Deep Fields Team

    2017-01-01

    Sensitive cosmic X-ray surveys with the Chandra, XMM-Newton, and now NuSTAR observatories have revolutionized our ability to find and study distant active galactic nuclei (AGNs), the main sites of supermassive black hole growth in the Universe. I will describe some recent discoveries about the demographics, physics, and ecology of distant AGNs coming from the deepest Chandra survey to date, the 7 Ms Chandra Deep Field-South. Some specific topics covered will include (1) robust X-ray spectral and variability characterization of the AGNs producing most of cosmic accretion power; (2) the demographics of AGNs in the first galaxies as revealed by direct detection and stacking; and (3) AGN/galaxy interactions as investigated via the host properties of X-ray AGNs. I will also briefly describe other remarkable discoveries coming from this survey; e.g., measurements of the evolving X-ray binary populations of normal and starburst galaxies.

  7. The cosmic star formation rate evolution from z = 5 to z = 0 from the VIMOS VLT deep survey

    NASA Astrophysics Data System (ADS)

    Tresse, L.; Ilbert, O.; Zucca, E.; Zamorani, G.; Bardelli, S.; Arnouts, S.; Paltani, S.; Pozzetti, L.; Bottini, D.; Garilli, B.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Picat, J.-P.; Scaramella, R.; Scodeggio, M.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnaboldi, M.; Bolzonella, M.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Iovino, A.; McCracken, H. J.; Marano, B.; Marinoni, C.; Mazure, A.; Meneux, B.; Merighi, R.; Pellò, R.; Pollo, A.; Radovich, M.; Bondi, M.; Bongiorno, A.; Busarello, G.; Cucciati, O.; Lamareille, F.; Mathez, G.; Mellier, Y.; Merluzzi, P.; Ripepi, V.

    2007-09-01

    Context: The VIMOS VLT Deep Survey (VVDS) was undertaken to map the evolution of galaxies, large scale structures, and active galaxy nuclei from the redshift spectroscopic measurements of ~105 objects down to an apparent magnitude IAB = 24, in combination with a multi-wavelength acquisition for radio, infrared, optical, ultraviolet, and X-rays data. Aims: We present the evolution of the comoving star formation rate (SFR) density in the redshift range 0 < z < 5 using the first epoch data release of the VVDS, that is 11564 spectra over 2200 arcmin2 in two fields of view, the VVDS-0226-04 and the VVDS-CDFS-0332-27, and the cosmological parameters (Ω_M, ΩΛ, h)=(0.3, 0.7, 0.7). Methods: We study the multi-wavelength non dust-corrected luminosity densities at 0 < z < 2 from the rest-frame far ultraviolet to the optical passbands, and the rest-frame 1500 Å luminosity functions and densities at 2.7 < z < 5. Results: They evolve from z=1.2 to z=0.05 according to (1+z)x with x = 2.05, 1.94, 1.92, 1.14, 0.73, 0.42, and 0.30 in the FUV-1500, NUV-2800, U-3600, B-4400, V-5500, R-6500, and I-7900 passbands, respectively. From z=1.2 to z=0.2 the B-band density for the irregular-like galaxies decreases markedly by a factor 3.5 while it increases by a factor 1.7 for the elliptical-like galaxies. We identify several SFR periods; from z=5 to 3.4 the FUV-band density increases by at most 0.5 dex, from z=3.4 to 1.2 it decreases by 0.08 dex, from z=1.2 to z=0.05 it declines steadily by 0.6 dex. For the most luminous MAB(1500 Å)<-21 galaxies the FUV-band density drops by 2 dex from z=3.9 to z=1.2, and for the intermediate -21surveys, at 0.4 ⪉ z ⪉ 2 the FUV seems obscured by a constant factor of ˜1.8-2 mag, while at z<0.5 it seems progressively less obscured by up to ˜0.9-1 mag when the dust-deficient early-type population is increasingly dominating the B-band density. Conclusions: The

  8. Autonomous application of quantitative PCR in the deep sea: in situ surveys of aerobic methanotrophs using the deep-sea environmental sample processor.

    PubMed

    Ussler, William; Preston, Christina; Tavormina, Patricia; Pargett, Doug; Jensen, Scott; Roman, Brent; Marin, Roman; Shah, Sunita R; Girguis, Peter R; Birch, James M; Orphan, Victoria; Scholin, Christopher

    2013-08-20

    Recent advances in ocean observing systems and genomic technologies have led to the development of the deep-sea environmental sample processor (D-ESP). The D-ESP filters particulates from seawater at depths up to 4000 m and applies a variety of molecular assays to the particulates, including quantitative PCR (qPCR), to identify particular organisms and genes in situ. Preserved samples enable laboratory-based validation of in situ results and expanded studies of genomic diversity and gene expression. Tests of the D-ESP at a methane-rich mound in the Santa Monica Basin centered on detection of 16S rRNA and particulate methane monooxygenase (pmoA) genes for two putative aerobic methanotrophs. Comparison of in situ qPCR results with laboratory-based assays of preserved samples demonstrates the D-ESP generated high-quality qPCR data while operating autonomously on the seafloor. Levels of 16S rRNA and pmoA cDNA detected in preserved samples are consistent with an active community of aerobic methanotrophs near the methane-rich mound. These findings are substantiated at low methane sites off Point Conception and in Monterey Bay where target genes are at or below detection limits. Successful deployment of the D-ESP is a major step toward developing autonomous systems to facilitate a wide range of marine microbiological investigations.

  9. AGN on the color-magnitude diagram: Results from a Deep Medium Band Survey with the Subaru Telescope in the MUSYC-ECDFS Region

    NASA Astrophysics Data System (ADS)

    Cardamone, Carolin; Urry, C. Megan; van Dokkum, P.; Schawinski, Kevin; Gawiser, E.; Brammer, G.; Taylor, N.; Treister, E.; Taniguchi, Y.; Virani, S.

    2009-09-01

    We investigate the host galaxy colors of X-ray detected AGN in the Extended Chandra Deep Field South.We have conducted deep medium-band imaging with the Subaru telescope, in 18 filters from 427 nm to 856 nm, of the MUSYC survey field. We detect 80,000 galaxies to equivalent magnitude R 27 mag, of which approximately 1,000 are X-ray-detected AGN observed with Chandra and XMM. Combining the Subaru data with optical, IR data and IRAC photometry we obtain photometric redshifts using EAZY, a fast public photometric redshift code, in the range 0

  10. Diversity of microbial eukaryotes in sediment at a deep-sea methane cold seep: surveys of ribosomal DNA libraries from raw sediment samples and two enrichment cultures.

    PubMed

    Takishita, Kiyotaka; Yubuki, Naoji; Kakizoe, Natsuki; Inagaki, Yuji; Maruyama, Tadashi

    2007-07-01

    Recent culture-independent surveys of eukaryotic small-subunit ribosomal DNA (SSU rDNA) from many environments have unveiled unexpectedly high diversity of microbial eukaryotes (microeukaryotes) at various taxonomic levels. However, such surveys were most probably biased by various technical difficulties, resulting in underestimation of microeukaryotic diversity. In the present study on oxygen-depleted sediment from a deep-sea methane cold seep of Sagami Bay, Japan, we surveyed the diversity of eukaryotic rDNA in raw sediment samples and in two enrichment cultures. More than half of all clones recovered from the raw sediment samples were of the basidiomycetous fungus Cryptococcus curvatus. Among other clones, phylotypes of eukaryotic parasites, such as Apicomplexa, Ichthyosporea, and Phytomyxea, were identified. On the other hand, we observed a marked difference in phylotype composition in the enrichment samples. Several phylotypes belonging to heterotrophic stramenopiles were frequently found in one enrichment culture, while a phylotype of Excavata previously detected at a deep-sea hydrothermal vent dominated the other. We successfully established a clonal culture of this excavate flagellate. Since these phylotypes were not identified in the raw sediment samples, the approach incorporating a cultivation step successfully found at least a fraction of the "hidden" microeukaryotic diversity in the environment examined.

  11. The ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: Implications for Spectral Line Intensity Mapping at Millimeter Wavelengths and CMB Spectral Distortions

    NASA Astrophysics Data System (ADS)

    Carilli, C. L.; Chluba, J.; Decarli, R.; Walter, F.; Aravena, M.; Wagg, J.; Popping, G.; Cortes, P.; Hodge, J.; Weiss, A.; Bertoldi, F.; Riechers, D.

    2016-12-01

    We present direct estimates of the mean sky brightness temperature in observing bands around 99 and 242 GHz due to line emission from distant galaxies. These values are calculated from the summed line emission observed in a blind, deep survey for spectral line emission from high redshift galaxies using ALMA (the ALMA spectral deep field observations “ASPECS” survey). In the 99 GHz band, the mean brightness will be dominated by rotational transitions of CO from intermediate and high redshift galaxies. In the 242 GHz band, the emission could be a combination of higher order CO lines, and possibly [C ii] 158 μm line emission from very high redshift galaxies (z ˜ 6-7). The mean line surface brightness is a quantity that is relevant to measurements of spectral distortions of the cosmic microwave background, and as a potential tool for studying large-scale structures in the early universe using intensity mapping. While the cosmic volume and the number of detections are admittedly small, this pilot survey provides a direct measure of the mean line surface brightness, independent of conversion factors, excitation, or other galaxy formation model assumptions. The mean surface brightness in the 99 GHZ band is: T B = 0.94 ± 0.09 μK. In the 242 GHz band, the mean brightness is: T B = 0.55 ± 0.033 μK. These should be interpreted as lower limits on the average sky signal, since we only include lines detected individually in the blind survey, while in a low resolution intensity mapping experiment, there will also be the summed contribution from lower luminosity galaxies that cannot be detected individually in the current blind survey.

  12. The VIMOS-VLT Deep Survey (VVDS). The dependence of clustering on galaxy stellar mass at z ~ 1

    NASA Astrophysics Data System (ADS)

    Meneux, B.; Guzzo, L.; Garilli, B.; Le Fèvre, O.; Pollo, A.; Blaizot, J.; De Lucia, G.; Bolzonella, M.; Lamareille, F.; Pozzetti, L.; Cappi, A.; Iovino, A.; Marinoni, C.; McCracken, H. J.; de la Torre, S.; Bottini, D.; Le Brun, V.; Maccagni, D.; Picat, J. P.; Scaramella, R.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Abbas, U.; Adami, C.; Arnouts, S.; Bardelli, S.; Bongiorno, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Cucciati, O.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Ilbert, O.; Marano, B.; Mazure, A.; Merighi, R.; Paltani, S.; Pellò, R.; Radovich, M.; Vergani, D.; Zamorani, G.; Zucca, E.

    2008-02-01

    We present a measurement of the dependence of galaxy clustering on galaxy stellar mass at redshift z˜0.9, based on the first-epoch data from the VVDS-Deep survey. Concentrating on the redshift interval 0.5survey, both from the data themselves and with a suite of realistic mock samples constructed by coupling the Millennium Simulation to semi-analytic models. We identify the range of masses within which our main conclusions are robust against these effects. Serious incompleteness in mass is present below log (M/M_⊙)=9.5, with about two thirds of the galaxies in the range 9109~M_⊙ to r_0=4.28-0.45+0.43~h-1 Mpc when only the most massive (M>1010.5~M_⊙) are considered. At the same time, we observe a significant increase in the slope, which over the same range of masses, changes from γ=1.67-0.07+0.08 to γ=2.28-0.27+0.28. Comparison to the SDSS measurements at z˜0.15 shows that the evolution of w_p(r_p) is significant for samples of galaxies with M<1010.5~M_⊙, while it is negligible for more massive objects. Considering the growth of structure, this implies that the linear bias bL of the most massive galaxies evolves more rapidly between these two cosmic epochs. We quantify this effect by computing the value of bL from the SDSS and VVDS clustering

  13. MOIRCS DEEP SURVEY. VI. NEAR-INFRARED SPECTROSCOPY OF K-SELECTED STAR-FORMING GALAXIES AT z {approx} 2

    SciTech Connect

    Yoshikawa, Tomohiro; Akiyama, Masayuki; Kajisawa, Masaru; Tokoku, Chihiro; Yamada, Toru; Ichikawa, Takashi; Alexander, David M.; Ohta, Kouji; Suzuki, Ryuji; Tanaka, Ichi; Omata, Koji; Nishimura, Tetsuo; Uchimoto, Yuka K.; Konishi, Masahiro; Koekemoer, Anton M.; Brandt, Niel

    2010-07-20

    We present the results of near-infrared multi-object spectroscopic observations for 37 BzK-color-selected star-forming galaxies conducted with MOIRCS on the Subaru Telescope. The sample is drawn from the K{sub s} -band-selected catalog of the MOIRCS Deep Survey in the GOODS-N region. About half of our samples are selected from the publicly available 24 {mu}m-source catalog of the Multiband Imaging Photometer for Spitzer on board the Spitzer Space Telescope. H{alpha} emission lines are detected from 23 galaxies, of which the median redshift is 2.12. We derived the star formation rates (SFRs) from extinction-corrected H{alpha} luminosities. The extinction correction is estimated from the spectral energy distribution (SED) fitting of multiband photometric data covering UV to near-infrared wavelengths. The Balmer decrement of the stacked emission lines shows that the amount of extinction for the ionized gas is larger than that for the stellar continuum. From a comparison of the extinction-corrected H{alpha} luminosity and other SFR indicators, we found that the relation between the dust properties of stellar continuum and ionized gas is different depending on the intrinsic SFR (differential extinction). We compared SFRs estimated from extinction-corrected H{alpha} luminosities with stellar masses estimated from SED fitting. The comparison shows no correlation between SFR and stellar mass. Some galaxies with stellar mass smaller than {approx}10{sup 10} M{sub sun} show SFRs higher than {approx}100 M{sub sun} yr{sup -1}. The specific SFRs (SSFRs) of these galaxies are remarkably high; galaxies which have SSFR higher than {approx}10{sup -8} yr{sup -1} are found in eight of the present sample. From the best-fit parameters of SED fitting for these high-SSFR galaxies, we find that the average age of the stellar population is younger than 100 Myr, which is consistent with the implied high SSFR. The large SFR implies the possibility that the high-SSFR galaxies significantly

  14. The VIMOS VLT Deep Survey. Evolution of the major merger rate since z ~ 1 from spectroscopically confirmed galaxy pairs

    NASA Astrophysics Data System (ADS)

    de Ravel, L.; Le Fèvre, O.; Tresse, L.; Bottini, D.; Garilli, B.; Le Brun, V.; Maccagni, D.; Scaramella, R.; Scodeggio, M.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Ilbert, O.; Iovino, A.; Lamareille, F.; McCracken, H. J.; Marano, B.; Marinoni, C.; Mazure, A.; Meneux, B.; Merighi, R.; Paltani, S.; Pellò, R.; Pollo, A.; Pozzetti, L.; Radovich, M.; Vergani, D.; Zamorani, G.; Zucca, E.; Bondi, M.; Bongiorno, A.; Brinchmann, J.; Cucciati, O.; de La Torre, S.; Gregorini, L.; Memeo, P.; Perez-Montero, E.; Mellier, Y.; Merluzzi, P.; Temporin, S.

    2009-05-01

    Context: The rate at which galaxies grow via successive mergers is a key element in understanding the main phases of galaxy evolution. Aims: We measure the evolution of the fraction of galaxies in pairs and the merging rate since redshift z 1 assuming a (H0 = 70 km s-1 Mpc-1, ΩM = 0.3 and ΩΛ = 0.7) cosmology. Methods: From the VIMOS VLT Deep Survey we use a sample of 6464 galaxies with I_AB ≤ 24 to identify 314 pairs of galaxies, each member with a secure spectroscopic redshift, which are close in both projected separation and in velocity. Results: We estimate that at z 0.9, 10.9 ± 3.2% of galaxies with MB(z) ≤ -18-Qz (Q = 1.11) are in pairs with separations Δ rp ≤ 20 h-1 kpc, Δ v≤ 500 km s-1, and with Δ MB ≤ 1.5, significantly larger than 3.8 ± 1.7% at z 0.5; thus, the pair fraction evolves as (1 + z)m with m = 4.73 ± 2.01. For bright galaxies with MB(z = 0) ≤ -18.77, the pair fraction is higher and its evolution with redshift is flatter with m = 1.50 ± 0.76, a property also observed for galaxies with increasing stellar masses. Early-type pairs (dry mergers) increase their relative fraction from 3% at z 0.9 to 12% at z 0.5. The star formation rate traced by the rest-frame [OII] EW increases by 26 ± 4% for pairs with the smallest separation rp ≤ 20 h-1 kpc. Following published prescriptions to derive merger timescales, we find that the merger rate of MB(z) ≤ -18-Qz galaxies evolves as N_mg = (4.96 ± 2.07)×10-4×(1 + z)2.20 ± 0.77 mergers Mpc-3 Gyr-1. Conclusions: The merger rate of galaxies with MB(z) ≤ -18-Qz has significantly evolved since z 1 and is strongly dependent on the luminosity or stellar mass of galaxies. The major merger rate increases more rapidly with redshift for galaxies with fainter luminosities or stellar mass, while the evolution of the merger rate for bright or massive galaxies is slower, indicating that the slow evolution reported for the brightest galaxies is not universal. The merger rate is also strongly

  15. The VIMOS VLT Deep Survey. Tracing the galaxy stellar mass assembly history over the last 8 Gyr

    NASA Astrophysics Data System (ADS)

    Vergani, D.; Scodeggio, M.; Pozzetti, L.; Iovino, A.; Franzetti, P.; Garilli, B.; Zamorani, G.; Maccagni, D.; Lamareille, F.; Le Fèvre, O.; Charlot, S.; Contini, T.; Guzzo, L.; Bottini, D.; Le Brun, V.; Picat, J. P.; Scaramella, R.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Cappi, A.; Ciliegi, P.; Foucaud, S.; Gavignaud, I.; Ilbert, O.; McCracken, H. J.; Marano, B.; Marinoni, C.; Mazure, A.; Meneux, B.; Merighi, R.; Paltani, S.; Pellò, R.; Pollo, A.; Radovich, M.; Zucca, E.; Bondi, M.; Bongiorno, A.; Brinchmann, J.; Cucciati, O.; de la Torre, S.; Gregorini, L.; Perez-Montero, E.; Mellier, Y.; Merluzzi, P.; Temporin, S.

    2008-08-01

    Aims: Our aim is to investigate the history of mass assembly for galaxies of different stellar masses and types. Methods: We selected a mass-limited sample of 4048 objects from the VIMOS VLT Deep Survey (VVDS) in the redshift interval 0.5 ≤ z ≤ 1.3. We then used an empirical criterion, based on the amplitude of the 4000 ÅBalmer break (D_n4000), to separate the galaxy population into spectroscopically early- and late-type systems. The equivalent width of the [OII]3727 line is used as proxy for the star formation activity. We also derived a type-dependent stellar mass function in three redshift bins. Results: We discuss to what extent stellar mass drives galaxy evolution, showing for the first time the interplay between stellar ages and stellar masses over the past 8 Gyr. Low-mass galaxies have small D_n4000 and at increasing stellar mass, the galaxy distribution moves to higher D_n4000 values as observed in the local Universe. As cosmic time goes by, we witness an increasing abundance of massive spectroscopically early-type systems at the expense of the late-type systems. This spectral transformation of late-type systems into old massive galaxies at lower redshift is a process started at early epochs (z > 1.3) and continuing efficiently down to the local Universe. This is also confirmed by the evolution of our type-dependent stellar mass function. The underlying stellar ages of late-type galaxies apparently do not show evolution, most likely as a result of a continuous and efficient formation of new stars. All star formation activity indicators consistently point towards a star formation history peaked in the past for massive galaxies, with little or no residual star formation taking place in the most recent epochs. In contrast, most of the low-mass systems show just the opposite characteristics, with significant star formation present at all epochs. The activity and efficiency of forming stars are mechanisms that depend on galaxy stellar mass, and the stellar

  16. A Determination of the Intergalactic Redshift Dependent UV-Optical-NIR Photon Density Using Deep Galaxy Survey Data and the Gamma-Ray Opacity of the Universe

    NASA Technical Reports Server (NTRS)

    Stecker, Floyd W.

    2012-01-01

    We calculate the intensity and photon spectrum of the intergalactic background light (IBL) as a function of red shift using an approach based on observational data obtained at in different wavelength bands from local to deep galaxy surveys. Our empirically based approach allows us, for the firs.t time, to obtain a completely model independent determination of the IBL and to quantify its uncertainties. Using our results on the IBL, we then place upper and lower limits on the opacity of the universe to gamma-rays, independent of previous constraints.

  17. The VVDS-VLA deep field. II. Optical and near infrared identifications of VLA S1.4 GHz > 80 μ Jy sources in the VIMOS VLT deep survey VVDS-02h field

    NASA Astrophysics Data System (ADS)

    Ciliegi, P.; Zamorani, G.; Bondi, M.; Pozzetti, L.; Bolzonella, M.; Gregorini, L.; Garilli, B.; Iovino, A.; McCracken, H. J.; Mellier, Y.; Radovich, M.; de Ruiter, H. R.; Parma, P.; Bottini, D.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Picat, J. P.; Scaramella, R.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnaboldi, M.; Arnouts, S.; Bardelli, S.; Cappi, A.; Charlot, S.; Contini, T.; Foucaud, S.; Franzetti, P.; Guzzo, L.; Ilbert, O.; Marano, B.; Marinoni, C.; Mathez, G.; Mazure, A.; Meneux, B.; Merighi, R.; Merluzzi, P.; Paltani, S.; Pollo, A.; Zucca, E.; Bongiorno, A.; Busarello, G.; Gavignaud, I.; Pellò, R.; Ripepi, V.; Rizzo, D.

    2005-10-01

    In this paper we present the optical and near-infrared identifications of the 1054 radio sources detected in the 20 cm deep radio survey down to a 5σ flux limit of ~80 μJy obtained with the VLA in the VIMOS VLT Deep Survey VVDS-02h deep field. Using U,B,V,R,I and K data, with limiting magnitudes of UAB˜25.4, BAB˜26.5, VAB˜26.2, RAB˜25.9 IAB˜25.0, JAB˜24.2, KAB˜23.9 (50% completeness) we identified 718 radio sources (~74% of the whole sample). The photometric redshift analysis shows that, in each magnitude bin, the radio sample has a higher median photometric redshift than the whole optical sample, while the median (V-I)AB color of the radio sources is redder than the median color of the whole optical sample. These results suggest that radio detection is preferentially selecting galaxies with higher intrinsic optical luminosity. From the analysis of the optical properties of the radio sources as function of the radio flux, we found that while about 35% of the radio sources are optically unidentified in the higher radio flux bin (S> 1.0 mJy), the percentage of unidentified sources decreases to about 25% in the faintest bins (S< 0.5 mJy). The median IAB magnitude for the total sample of radio sources, i.e. including also the unidentified ones, is brighter in the faintest radio bins than in the bin with higher radio flux. This suggests that most of the faintest radio sources are likely to be associated to relatively lower radio luminosity objects at relatively modest redshift, rather than radio-powerful, AGN type objects at high redshift. Using a classification in early-type and late-type galaxies based on the (B-I)AB color and the photometric redshift, we found that the majority of the radio sources below ~0.15 mJy are indeed late-type star forming galaxies. Finally, the radio sources without optical counterpart in our deep imaging have a median radio flux of 0.15 mJy, equal to that of identified sources. Given the very faint optical limits, these

  18. A LABOCA Survey of the Extended Chandra Deep Field South—Submillimeter Properties of Near-infrared Selected Galaxies

    NASA Astrophysics Data System (ADS)

    Greve, T. R.; Weiβ, A.; Walter, F.; Smail, I.; Zheng, X. Z.; Knudsen, K. K.; Coppin, K. E. K.; Kovács, A.; Bell, E. F.; de Breuck, C.; Dannerbauer, H.; Dickinson, M.; Gawiser, E.; Lutz, D.; Rix, H.-W.; Schinnerer, E.; Alexander, D.; Bertoldi, F.; Brandt, N.; Chapman, S. C.; Ivison, R. J.; Koekemoer, A. M.; Kreysa, E.; Kurczynski, P.; Menten, K.; Siringo, G.; Swinbank, M.; van der Werf, P.

    2010-08-01

    Using the 330 hr ESO-MPG 870 μm survey of the Extended Chandra Deep Field South (ECDF-S) obtained with the Large Apex BOlometer CAmera (LABOCA) on the Atacama Pathfinder EXperiment (APEX), we have carried out a stacking analysis at submillimeter (submm) wavelengths of a sample of 8266 near-infra-red (near-IR) selected (K vega <= 20) galaxies, including 893 BzK galaxies, 1253 extremely red objects (EROs), and 737 distant red galaxies (DRGs), selected from the Multi-wavelength Survey by Yale-Chile (MUSYC). We measure average 870 μm fluxes of 0.22 ± 0.01 mJy (22.0σ), 0.48 ± 0.04 mJy (12.0σ), 0.39 ± 0.03 mJy (13.0σ), and 0.43 ± 0.04 mJy (10.8σ) for the K vega <= 20, BzK, ERO, and DRG samples, respectively. For the BzK, ERO, and DRG sub-samples, which overlap to some degree and are likely to be at z ~= 1-2, this implies an average far-IR luminosity of ~(1-5) × 1011 Lsun and star formation rate (SFR) of ~20-90 Msun . Splitting the BzK galaxies into star-forming (sBzK) and passive (pBzK) galaxies, the former is significantly detected (0.50 ± 0.04 mJy, 12.5σ) while the latter is only marginally detected (0.34 ± 0.10 mJy, 3.4σ), thus confirming that the sBzK and pBzK criteria to some extent select obscured, star-forming, and truly passive galaxies, respectively. The K vega <= 20 galaxies are found to contribute 7.27 ± 0.34 Jy deg-2 (16.5% ± 5.7%) to the 870 μm extragalactic background light (EBL). sBzK and pBzK galaxies contribute 1.49 ± 0.22 Jy deg-2 (3.4% ± 1.3%) and 0.20 ± 0.14 Jy deg-2 (0.5% ± 0.3%) to the EBL. We present the first delineation of the average submm signal from the K vega <= 20 selected galaxies and their contribution to the submm EBL as a function of (photometric) redshift, and find a decline in the average submm signal (and therefore IR luminosity and SFR) by a factor ~2-3 from z ~ 2 to z ~ 0. This is in line with a cosmic star formation history in which the star formation activity in galaxies increases significantly at z >~ 1. A

  19. A LABOCA SURVEY OF THE EXTENDED CHANDRA DEEP FIELD SOUTH-SUBMILLIMETER PROPERTIES OF NEAR-INFRARED SELECTED GALAXIES

    SciTech Connect

    Greve, T. R.; Walter, F.; Bell, E. F.; Dannerbauer, H.; Rix, H.-W.; Schinnerer, E.; Weiss, A.; Kovacs, A.; Smail, I.; Coppin, K. E. K.; Alexander, D.; Zheng, X. Z.; Knudsen, K. K.; Bertoldi, F.; De Breuck, C.; Dickinson, M.; Gawiser, E.; Lutz, D.; Brandt, N.; Chapman, S. C.

    2010-08-10

    Using the 330 hr ESO-MPG 870 {mu}m survey of the Extended Chandra Deep Field South (ECDF-S) obtained with the Large Apex BOlometer CAmera (LABOCA) on the Atacama Pathfinder EXperiment (APEX), we have carried out a stacking analysis at submillimeter (submm) wavelengths of a sample of 8266 near-infra-red (near-IR) selected (K {sub vega} {<=} 20) galaxies, including 893 BzK galaxies, 1253 extremely red objects (EROs), and 737 distant red galaxies (DRGs), selected from the Multi-wavelength Survey by Yale-Chile (MUSYC). We measure average 870 {mu}m fluxes of 0.22 {+-} 0.01 mJy (22.0{sigma}), 0.48 {+-} 0.04 mJy (12.0{sigma}), 0.39 {+-} 0.03 mJy (13.0{sigma}), and 0.43 {+-} 0.04 mJy (10.8{sigma}) for the K {sub vega} {<=} 20, BzK, ERO, and DRG samples, respectively. For the BzK, ERO, and DRG sub-samples, which overlap to some degree and are likely to be at z {approx_equal} 1-2, this implies an average far-IR luminosity of {approx}(1-5) x 10{sup 11} L{sub sun} and star formation rate (SFR) of {approx}20-90 M{sub sun} . Splitting the BzK galaxies into star-forming (sBzK) and passive (pBzK) galaxies, the former is significantly detected (0.50 {+-} 0.04 mJy, 12.5{sigma}) while the latter is only marginally detected (0.34 {+-} 0.10 mJy, 3.4{sigma}), thus confirming that the sBzK and pBzK criteria to some extent select obscured, star-forming, and truly passive galaxies, respectively. The K {sub vega} {<=} 20 galaxies are found to contribute 7.27 {+-} 0.34 Jy deg{sup -2} (16.5% {+-} 5.7%) to the 870 {mu}m extragalactic background light (EBL). sBzK and pBzK galaxies contribute 1.49 {+-} 0.22 Jy deg{sup -2} (3.4% {+-} 1.3%) and 0.20 {+-} 0.14 Jy deg{sup -2} (0.5% {+-} 0.3%) to the EBL. We present the first delineation of the average submm signal from the K {sub vega} {<=} 20 selected galaxies and their contribution to the submm EBL as a function of (photometric) redshift, and find a decline in the average submm signal (and therefore IR luminosity and SFR) by a factor {approx}2

  20. Ly{alpha} EMITTERS AT z = 7 IN THE SUBARU/XMM-NEWTON DEEP SURVEY FIELD: PHOTOMETRIC CANDIDATES AND LUMINOSITY FUNCTION

    SciTech Connect

    Ota, Kazuaki; Ouchi, Masami; Iye, Masanori; Kashikawa, Nobunari; Kobayashi, Masakazu A. R.; Morokuma, Tomoki; Furusawa, Hisanori; Shimasaku, Kazuhiro; Totani, Tomonori; Nagashima, Masahiro; Harayama, Atsushi; Kodaka, Natsuki; Tajitsu, Akito; Hattori, Takashi

    2010-10-10

    We conducted a deep narrowband NB973 (FWHM = 200 A centered at 9755 A) survey of z = 7 Ly{alpha} emitters (LAEs) in the Subaru/XMM-Newton Deep Survey Field, using the fully depleted CCDs newly installed on the Subaru Telescope Suprime-Cam, which is twice more sensitive to z = 7 Ly{alpha} at {approx}1 {mu}m than the previous CCDs. Reaching the depth 0.5 mag deeper than our previous survey in the Subaru Deep Field that led to the discovery of a z = 6.96 LAE, we detected three probable z = 7 LAE candidates. Even if all the candidates are real, the Ly{alpha} luminosity function (LF) at z = 7 shows a significant deficit from the LF at z = 5.7 determined by previous surveys. The LAE number and Ly{alpha} luminosity densities at z = 7 are {approx}7.7%-54% and {approx}5.5%-39%, respectively, of those at z = 5.7, to the Ly{alpha} line luminosity limit of L(Ly{alpha}) {approx}> 9.2 x 10{sup 42} erg s{sup -1}. This could be due to evolution of the LAE population at these epochs as a recent galaxy evolution model predicts that the LAE modestly evolves from z = 5.7 to 7. However, even after correcting for this effect of galaxy evolution on the decrease in LAE number density, the z = 7 Ly{alpha} LF still shows a deficit from z = 5.7 LF. This might reflect the attenuation of Ly{alpha} emission by neutral hydrogen remaining at the epoch of reionization and suggests that reionization of the universe might not be complete yet at z = 7. If we attribute the density deficit to reionization, the intergalactic medium transmission for Ly{alpha} photons at z = 7 would be 0.4 {<=} T {sup IGM}{sub Ly{alpha} {<=}} 1, supporting the possible higher neutral fraction at the earlier epochs at z > 6 suggested by the previous surveys of z = 5.7-7 LAEs, z {approx} 6 quasars, and z > 6 gamma-ray bursts.

  1. Lyα Emitters at z = 7 in the Subaru/XMM-Newton Deep Survey Field: Photometric Candidates and Luminosity Functions

    NASA Astrophysics Data System (ADS)

    Ota, Kazuaki; Iye, Masanori; Kashikawa, Nobunari; Shimasaku, Kazuhiro; Ouchi, Masami; Totani, Tomonori; Kobayashi, Masakazu A. R.; Nagashima, Masahiro; Harayama, Atsushi; Kodaka, Natsuki; Morokuma, Tomoki; Furusawa, Hisanori; Tajitsu, Akito; Hattori, Takashi

    2010-10-01

    We conducted a deep narrowband NB973 (FWHM = 200 Å centered at 9755 Å) survey of z = 7 Lyα emitters (LAEs) in the Subaru/XMM-Newton Deep Survey Field, using the fully depleted CCDs newly installed on the Subaru Telescope Suprime-Cam, which is twice more sensitive to z = 7 Lyα at ~1 μm than the previous CCDs. Reaching the depth 0.5 mag deeper than our previous survey in the Subaru Deep Field that led to the discovery of a z = 6.96 LAE, we detected three probable z = 7 LAE candidates. Even if all the candidates are real, the Lyα luminosity function (LF) at z = 7 shows a significant deficit from the LF at z = 5.7 determined by previous surveys. The LAE number and Lyα luminosity densities at z = 7 are ~7.7%-54% and ~5.5%-39%, respectively, of those at z = 5.7, to the Lyα line luminosity limit of L(Lyα) >~ 9.2 × 1042 erg s-1. This could be due to evolution of the LAE population at these epochs as a recent galaxy evolution model predicts that the LAE modestly evolves from z = 5.7 to 7. However, even after correcting for this effect of galaxy evolution on the decrease in LAE number density, the z = 7 Lyα LF still shows a deficit from z = 5.7 LF. This might reflect the attenuation of Lyα emission by neutral hydrogen remaining at the epoch of reionization and suggests that reionization of the universe might not be complete yet at z = 7. If we attribute the density deficit to reionization, the intergalactic medium transmission for Lyα photons at z = 7 would be 0.4 <= T IGM Lyα <= 1, supporting the possible higher neutral fraction at the earlier epochs at z > 6 suggested by the previous surveys of z = 5.7-7 LAEs, z ~ 6 quasars, and z > 6 gamma-ray bursts. Based on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan.

  2. The evolution of the near-infrared galaxy luminosity function and colour bimodality up to z ~= 2 from the UKIDSS Ultra Deep Survey Early Data Release

    NASA Astrophysics Data System (ADS)

    Cirasuolo, M.; McLure, R. J.; Dunlop, J. S.; Almaini, O.; Foucaud, S.; Smail, Ian; Sekiguchi, K.; Simpson, C.; Eales, S.; Dye, S.; Watson, M. G.; Page, M. J.; Hirst, P.

    2007-09-01

    We present new results on the cosmological evolution of the near-infrared (near-IR) galaxy luminosity function (LF), derived from the analysis of a new sample of ~22000KAB <= 22.5 galaxies selected over an area of 0.6 deg2 from the Early Data Release of the UKIDSS Ultra Deep Survey (UDS). Our study has exploited the multiwavelength coverage of the UDS field provided by the new UKIDSS WFCAM K- and J-band imaging, the Subaru/XMM-Newton Deep Survey and the Spitzer Wide-Area Infrared Extragalactic survey. The unique combination of large area and depth provided by this new survey minimizes the complicating effect of cosmic variance and has allowed us, for the first time, to trace the evolution of the brightest sources out to z ~= 2 with good statistical accuracy. In agreement with previous studies, we find that the characteristic luminosity of the near-IR LF brightens by ~=1 mag between z = 0 and z ~= 2, while the total density decreases by a factor of ~=2. Using the rest-frame (U - B) colour to split the sample into red and blue galaxies, we confirm the classic luminosity-dependent colour bimodality at z <~ 1. However, the strength of the colour bimodality is found to be a decreasing function of redshift, and seems to disappear by z >~ 1.5. Due to the large size of our sample, we are able to investigate the differing cosmological evolution of the red and blue galaxy populations. It is found that the space density of the brightest red galaxies (MK <= - 23) stays approximately constant with redshift, and that these sources dominate the bright end of the LF at redshifts z <~ 1. In contrast, the brightening of the characteristic luminosity and mild decrease in space density displayed by the blue galaxy population leads them to dominate the bright end of the LF at redshifts z >~ 1.

  3. 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

    NASA Astrophysics Data System (ADS)

    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.

  4. Comparison of the VIMOS-VLT Deep Survey with the Munich semi-analytical model. I. Magnitude counts, redshift distribution, colour bimodality, and galaxy clustering

    NASA Astrophysics Data System (ADS)

    de la Torre, S.; Meneux, B.; De Lucia, G.; Blaizot, J.; Le Fèvre, O.; Garilli, B.; Cucciati, O.; Mellier, Y.; Pollo, A.; Abbas, U.; Bottini, D.; Le Brun, V.; Maccagni, D.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Ilbert, O.; Iovino, A.; McCracken, H. J.; Marinoni, C.; Mazure, A.; Merighi, R.; Paltani, S.; Pelló, R.; Pozzetti, L.; Vergani, D.; Zamorani, G.; Zucca, E.

    2011-01-01

    Aims: This paper presents a detailed comparison between high-redshift observations from the VIMOS-VLT Deep Survey (VVDS) and predictions from the Munich semi-analytical model of galaxy formation. In particular, we focus this analysis on the magnitude, redshift, and colour distributions of galaxies, as well as their clustering properties. Methods: We constructed 100 quasi-independent mock catalogues, using the output of the semi-analytical model presented in De Lucia & Blaizot (2007, MNRAS, 375, 2). We then applied the same observational selection function of the VVDS-Deep survey, so as to carry out a fair comparison between models and observations. Results: We find that the semi-analytical model reproduces well the magnitude counts in the optical bands. It tends, however, to overpredict the abundance of faint red galaxies, in particular in the i' and z' bands. Model galaxies exhibit a colour bimodality that is only in qualitative agreement with the data. In particular, we find that the model tends to overpredict the number of red galaxies at low redshift and of blue galaxies at all redshifts probed by VVDS-Deep observations, although a large fraction of the bluest observed galaxies is absent from the model. In addition, the model overpredicts by about 14 per cent the number of galaxies observed at 0.2 < z < 1 with IAB < 24. When comparing the galaxy clustering properties, we find that model galaxies are more strongly clustered than observed ones at all redshift from z = 0.2 to z = 2, with the difference being less significant above z ≃ 1. When splitting the samples into red and blue galaxies, we find that the observed clustering of blue galaxies is well reproduced by the model, while red model galaxies are much more clustered than observed ones, being principally responsible for the strong global clustering found in the model. Conclusions: Our results show that the discrepancies between Munich semi-analytical model predictions and VVDS-Deep observations

  5. Cosmic Shear Results from the Deep Lens Survey. I. Joint Constraints on Ω M and σ8 with a Two-dimensional Analysis

    NASA Astrophysics Data System (ADS)

    Jee, M. James; Tyson, J. Anthony; Schneider, Michael D.; Wittman, David; Schmidt, Samuel; Hilbert, Stefan

    2013-03-01

    We present a cosmic shear study from the Deep Lens Survey (DLS), a deep BVRz multi-band imaging survey of five 4 deg2 fields with two National Optical Astronomy Observatory (NOAO) 4 m telescopes at Kitt Peak and Cerro Tololo. For both telescopes, the change of the point-spread-function (PSF) shape across the focal plane is complicated, and the exposure-to-exposure variation of this position-dependent PSF change is significant. We overcome this challenge by modeling the PSF separately for individual exposures and CCDs with principal component analysis (PCA). We find that stacking these PSFs reproduces the final PSF pattern on the mosaic image with high fidelity, and the method successfully separates PSF-induced systematics from gravitational lensing effects. We calibrate our shears and estimate the errors, utilizing an image simulator, which generates sheared ground-based galaxy images from deep Hubble Space Telescope archival data with a realistic atmospheric turbulence model. For cosmological parameter constraints, we marginalize over shear calibration error, photometric redshift uncertainty, and the Hubble constant. We use cosmology-dependent covariances for the Markov Chain Monte Carlo analysis and find that the role of this varying covariance is critical in our parameter estimation. Our current non-tomographic analysis alone constrains the Ω M -σ8 likelihood contour tightly, providing a joint constraint of Ω M = 0.262 ± 0.051 and σ8 = 0.868 ± 0.071. We expect that a future DLS weak-lensing tomographic study will further tighten these constraints because explicit treatment of the redshift dependence of cosmic shear more efficiently breaks the Ω M -σ8 degeneracy. Combining the current results with the Wilkinson Microwave Anisotropy Probe 7 year (WMAP7) likelihood data, we obtain Ω M = 0.278 ± 0.018 and σ8 = 0.815 ± 0.020.

  6. A Systematic Search for Periodically Varying Quasars in Pan-STARRS1: An Extended Baseline Test in Medium Deep Survey Field MD09

    NASA Astrophysics Data System (ADS)

    Liu, T.; Gezari, S.; Burgett, W.; Chambers, K.; Draper, P.; Hodapp, K.; Huber, M.; Kudritzki, R.-P.; Magnier, E.; Metcalfe, N.; Tonry, J.; Wainscoat, R.; Waters, C.

    2016-12-01

    We present a systematic search for periodically varying quasars and supermassive black hole binary (SMBHB) candidates in the Pan-STARRS1 (PS1) Medium Deep Survey’s MD09 field. From a color-selected sample of 670 quasars extracted from a multi-band deep-stack catalog of point sources, we locally select variable quasars and look for coherent periods with the Lomb-Scargle periodogram. Three candidates from our sample demonstrate strong variability for more than ˜3 cycles, and their PS1 light curves are well fitted to sinusoidal functions. We test the persistence of the candidates’ apparent periodic variations detected during the 4.2 years of the PS1 survey with archival photometric data from the SDSS Stripe 82 survey or new monitoring with the Large Monolithic Imager at the Discovery Channel Telescope. None of the three periodic candidates (including PSO J334.2028+1.4075) remain persistent over the extended baseline of 7-14 years, corresponding to a detection rate of <1 in 670 quasars in a search area of ≈5 deg2. Even though SMBHBs should be a common product of the hierarchal growth of galaxies, and periodic variability in SMBHBs has been theoretically predicted, a systematic search for such signatures in a large optical survey is strongly limited by its temporal baseline and the “red noise” associated with normal quasar variability. We show that follow-up long-term monitoring (≳5 cycles) is crucial to our search for these systems.

  7. Physical properties of galaxies and their evolution in the VIMOS VLT Deep Survey. I. The evolution of the mass-metallicity relation up to z ~ 0.9

    NASA Astrophysics Data System (ADS)

    Lamareille, F.; Brinchmann, J.; Contini, T.; Walcher, C. J.; Charlot, S.; Pérez-Montero, E.; Zamorani, G.; Pozzetti, L.; Bolzonella, M.; Garilli, B.; Paltani, S.; Bongiorno, A.; Le Fèvre, O.; Bottini, D.; Le Brun, V.; Maccagni, D.; Scaramella, R.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnouts, S.; Bardelli, S.; Cappi, A.; Ciliegi, P.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Ilbert, O.; Iovino, A.; McCracken, H. J.; Marano, B.; Marinoni, C.; Mazure, A.; Meneux, B.; Merighi, R.; Pellò, R.; Pollo, A.; Radovich, M.; Vergani, D.; Zucca, E.; Romano, A.; Grado, A.; Limatola, L.

    2009-02-01

    Aims: We want to derive the mass-metallicity relation of star-forming galaxies up to z ~ 0.9, using data from the VIMOS VLT Deep Survey. The mass-metallicity relation is commonly understood as the relation between the stellar mass and the gas-phase oxygen abundance. Methods: Automatic measurement of emission-line fluxes and equivalent widths have been performed on the full spectroscopic sample of the VIMOS VLT Deep Survey. This sample is divided into two sub-samples depending on the apparent magnitude selection: wide (IAB < 22.5) and deep (IAB < 24). These two samples span two different ranges of stellar masses. Emission-line galaxies have been separated into star-forming galaxies and active galactic nuclei using emission line ratios. For the star-forming galaxies the emission line ratios have also been used to estimate gas-phase oxygen abundance, using empirical calibrations renormalized in order to give consistent results at low and high redshifts. The stellar masses have been estimated by fitting the whole spectral energy distributions with a set of stellar population synthesis models. Results: We assume at first order that the shape of the mass-metallicity relation remains constant with redshift. Then we find a stronger metallicity evolution in the wide sample as compared to the deep sample. We thus conclude that the mass-metallicity relation is flatter at higher redshift. At z ~ 0.77, galaxies at 109.4 solar masses have -0.18 dex lower metallicities than galaxies of similar masses in the local universe, while galaxies at 1010.2 solar masses have -0.28 dex lower metallicities. By comparing the mass-metallicity and luminosity-metallicity relations, we also find an evolution in mass-to-light ratio: galaxies at higher redshifts being more active. The observed flattening of the mass-metallicity relation at high redshift is analyzed as evidence in favor of the open-closed model. Based on data obtained with the European Southern Observatory Very Large Telescope

  8. VizieR Online Data Catalog: Deep GALEX NUV survey of the Kepler field. I. (Olmedo+, 2015)

    NASA Astrophysics Data System (ADS)

    Olmedo, M.; Lloyd, J.; Mamajek, E. E.; Chavez, M.; Bertone, E.; Martin, D. C.; Neill, J. D.

    2016-02-01

    As part of the Galaxy Evolution Explorer (GALEX) Complete All-Sky UV Survey Extension (CAUSE) survey, Cornell University funded 300 orbits to complete the spatial coverage of the Kepler field through 2012 August-September (PI J. Lloyd). The GALEX-CAUSE Kepler Catalog (GCK) has 660928 NUV sources which are contained in Table 4. A subsample of this catalog is contained in Table 5, composed of 327 GCK objects with counter-parts in the Kepler Input Catalog hosting confirmed exoplanets. (2 data files).

  9. Evolution Of The Galaxy Major Merger Rate Since Z 6 In The Muse Hubble Ultra Deep Field Survey.

    NASA Astrophysics Data System (ADS)

    Ventou, E.; Contini, T.; MUSE-GTO Collaboration

    2017-06-01

    Over the past two decades, strong evidence that galaxies have undergone a significant evolution over cosmic time were found. Do galaxy mergers, one of the main driving mechanisms behind the growth of galaxies, played a key role in their evolution at significant look-back time? Due to the difficulty to identify these violent interactions between galaxies at high redshifts, the major merger rate, involving two galaxies of similar masses, was constrained so far up to redshift z 3, from previous studies of spectrocopic pair counts. Thanks to MUSE, which is perfectly suited to identify close pairs of galaxies with secure spectroscopic redshifts, we are now able to extend such studies up to z 6. I will present the results obtained from deep (10-30h) MUSE observations in the Hubble Ultra Deep Field. We provide the first constraints on the galaxy major merger evolution over 12 Gyrs (0.2 < z < 6) and over a broad range of stellar masses, showing that there is a flattening of the major merger rate evolution at very high redshift.

  10. The XMM deep survey in the CDF-S. VIII. X-ray properties of the two brightest sources

    NASA Astrophysics Data System (ADS)

    Iwasawa, K.; Vignali, C.; Comastri, A.; Gilli, R.; Vito, F.; Brandt, W. N.; Carrera, F. J.; Lanzuisi, G.; Falocco, S.; Vagnetti, F.

    2015-02-01

    We present results from the deep XMM-Newton observations of the two brightest X-ray sources in the Chandra Deep Field South (CDFS), PID 203 (z = 0.544) and PID 319 (z = 0.742). The long exposure of 2.5 Ms over a 10 year period (net 4 yr with a 6 yr gap) makes it possible to obtain high quality X-ray spectra of these two Type I AGN with X-ray luminosity of 1044 erg s-1, which is the typical luminosity for low-redshift PG quasars, and track their X-ray variability both in flux and spectral shape. Both sources showed X-ray flux variability of ~10-20% in rms, which is similar in the soft (0.5-2 keV) and hard (2-7 keV) bands. PID 203, which has evidence for optical extinction, shows modest amount of absorption (NH≤ 1 × 1021 cm-2) in the X-ray spectrum. Fe K emission is strongly detected in both objects with EW ~ 0.2 keV. The lines in both objects are moderately broad and exhibit marginal evidence for variability in shape and flux, indicating that the bulk of the line emission comes from their accretion disks rather than distant tori.

  11. Comparison of galaxy clusters selected by weak-lensing, optical spectroscopy, and X-rays in the deep lens survey F2 field

    SciTech Connect

    Starikova, Svetlana; Jones, Christine; Forman, William R.; Vikhlinin, Alexey; Kurtz, Michael J.; Fabricant, Daniel G.; Murray, Stephen S.; Geller, Margaret J.; Dell'Antonio, Ian P.

    2014-05-10

    We compare galaxy clusters selected in Chandra and XMM-Newton X-ray observations of the 4 deg{sup 2} Deep Lens Survey (DLS) F2 field to the cluster samples previously selected in the same field from a sensitive weak-lensing shear map derived from the DLS and from a detailed galaxy redshift survey—the Smithsonian Hectospec Lensing Survey (SHELS). Our Chandra and XMM-Newton observations cover 1.6 deg{sup 2} of the DLS F2 field, including all 12 weak-lensing peaks above a signal-to-noise ratio of 3.5, along with 16 of the 20 SHELS clusters with published velocity dispersions >500 km s{sup –1}. We detect 26 extended X-ray sources in this area and confirm 23 of them as galaxy clusters using the optical imaging. Approximately 75% of clusters detected in either X-ray or spectroscopic surveys are found in both; these follow the previously established scaling relations between velocity dispersion, L {sub X}, and T {sub X}. A lower percentage, 60%, of clusters are in common between X-ray and DLS samples. With the exception of a high false-positive rate in the DLS weak-lensing search (5 out of 12 DLS candidates appear to be false), differences between the three cluster detection methods can be attributed primarily to observational uncertainties and intrinsic scatter between different observables and cluster mass.

  12. The VIMOS-VLT Deep Survey First Epoch observations: evolution of galaxies, large scale structures and AGNs over 90% of the current age of the Universe

    NASA Astrophysics Data System (ADS)

    Le Fèvre, O.; Vettolani, G.; Bottini, D.; Garilli, B.; Le Brun, V.; Maccagni, D.; Picat, J.-P.; Scaramella, R.; Scodeggio, M.; Tresse, L.; Zanichelli, A.; Adami, C.; Arnaboldi, M.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Franzetti, P.; Foucaud, S.; Gavignaud, I.; Guzzo, L.; Ilbert, O.; Iovino, A.; McCracken, H.-J.; Marano, B.; Marinoni, C.; Mazure, A.; Meneux, B.; Merighi, R.; Paltani, S.; Pellò, R.; Pollo, A.; Pozzetti, L.; Radovich, M.; Zamorani, G.; Zucca, E.; Bondi, M.; Bongiorno, A.; Busarello, G.; Lamareille, F.; Mathez, G.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2005-03-01

    THE VIMOS VLT DEEP SURVEY (VVDS) IS A MAJOR REDSHIFT SURVEY OF THE DISTANT UNIVERSE, AIMED AT STUDYING THE EVOLUTION OF GALAXIES, LARGE SCALE STRUCTURES AND AGNS OVER MORE THAN 90% OF THE AGE OF THE UNIVERSE. A TOTAL OF 41000 SPECTRA HAVE BEEN OBSERVED SO FAR. FROM THE FIRST EPOCH OBSERVATIONS CONDUCTED WITH VIMOS, WE HAVE ASSEMBLED ~11000 REDSHIFTS FOR GALAXIES WITH 0 £ Z £ 5 SELECTED WITH MAGNITUDE IAB £ 24 IN AN AREA 3.1 TIMES THE AREA OF THE FULL MOON. WE PRESENT EVIDENCE FOR A STRONG EVOLUTION OF THE LUMINOSITY OF GALAXIES AND SHOW THAT GALAXIES ARE ALREADY DISTRIBUTED IN DENSE STRUCTURES AT Z ~ 1.5. THE HIGH REDSHIFT POPULATION OF ~1000 GALAXIES WITH 1.4 £ Z £ 5 APPEARS TO BE MORE NUMEROUS THAN PREVIOUSLY BELIEVED. AS THE SURVEY CONTINUES, WE ARE ASSEMBLING MULTI-WAVELENGTH DATA IN COLLABORATION WITH OTHER TEAMS (GALEX, SPITZER-SWIRE, XMM-LSS, VLA), AS WELL AS EXPANDING TO LARGER SCALES (~100 MPC) TO PROBE THE UNIVERSE IN AN UNPRECEDENTED WAY.

  13. A survey of surveys

    SciTech Connect

    Kent, S.M.

    1994-11-01

    A new era for the field of Galactic structure is about to be opened with the advent of wide-area digital sky surveys. In this article, the author reviews the status and prospects for research for 3 new ground-based surveys: the Sloan Digital Sky Survey (SDSS), the Deep Near-Infrared Survey of the Southern Sky (DENIS) and the Two Micron AU Sky Survey (2MASS). These surveys will permit detailed studies of Galactic structure and stellar populations in the Galaxy with unprecedented detail. Extracting the information, however, will be challenging.

  14. Applying species-tree analyses to deep phylogenetic histories: challenges and potential suggested from a survey of empirical phylogenetic studies.

    PubMed

    Lanier, Hayley C; Knowles, L Lacey

    2015-02-01

    Coalescent-based methods for species-tree estimation are becoming a dominant approach for reconstructing species histories from multi-locus data, with most of the studies examining these methodologies focused on recently diverged species. However, deeper phylogenies, such as the datasets that comprise many Tree of Life (ToL) studies, also exhibit gene-tree discordance. This discord may also arise from the stochastic sorting of gene lineages during the speciation process (i.e., reflecting the random coalescence of gene lineages in ancestral populations). It remains unknown whether guidelines regarding methodologies and numbers of loci established by simulation studies at shallow tree depths translate into accurate species relationships for deeper phylogenetic histories. We address this knowledge gap and specifically identify the challenges and limitations of species-tree methods that account for coalescent variance for deeper phylogenies. Using simulated data with characteristics informed by empirical studies, we evaluate both the accuracy of estimated species trees and the characteristics associated with recalcitrant nodes, with a specific focus on whether coalescent variance is generally responsible for the lack of resolution. By determining the proportion of coalescent genealogies that support a particular node, we demonstrate that (1) species-tree methods account for coalescent variance at deep nodes and (2) mutational variance - not gene-tree discord arising from the coalescent - posed the primary challenge for accurate reconstruction across the tree. For example, many nodes were accurately resolved despite predicted discord from the random coalescence of gene lineages and nodes with poor support were distributed across a range of depths (i.e., they were not restricted to a particular recent divergences). Given their broad taxonomic scope and large sampling of taxa, deep level phylogenies pose several potential methodological complications including

  15. THE MULTIWAVELENGTH SURVEY BY YALE-CHILE (MUSYC): DEEP MEDIUM-BAND OPTICAL IMAGING AND HIGH-QUALITY 32-BAND PHOTOMETRIC REDSHIFTS IN THE ECDF-S

    SciTech Connect

    Cardamone, Carolin N.; Van Dokkum, Pieter G.; Urry, C. Megan; Brammer, Gabriel; Taniguchi, Yoshi; Gawiser, Eric; Bond, Nicholas; Taylor, Edward; Damen, Maaike; Treister, Ezequiel; Cobb, Bethany E.; Schawinski, Kevin; Lira, Paulina; Murayama, Takashi; Saito, Tomoki; Sumikawa, Kentaro

    2010-08-15

    We present deep optical 18-medium-band photometry from the Subaru telescope over the {approx}30' x 30' Extended Chandra Deep Field-South, as part of the Multiwavelength Survey by Yale-Chile (MUSYC). This field has a wealth of ground- and space-based ancillary data, and contains the GOODS-South field and the Hubble Ultra Deep Field. We combine the Subaru imaging with existing UBVRIzJHK and Spitzer IRAC images to create a uniform catalog. Detecting sources in the MUSYC 'BVR' image we find {approx}40,000 galaxies with R {sub AB} < 25.3, the median 5{sigma} limit of the 18 medium bands. Photometric redshifts are determined using the EAzY code and compared to {approx}2000 spectroscopic redshifts in this field. The medium-band filters provide very accurate redshifts for the (bright) subset of galaxies with spectroscopic redshifts, particularly at 0.1 < z < 1.2 and at z {approx}> 3.5. For 0.1 < z < 1.2, we find a 1{sigma} scatter in {Delta}z/(1 + z) of 0.007, similar to results obtained with a similar filter set in the COSMOS field. As a demonstration of the data quality, we show that the red sequence and blue cloud can be cleanly identified in rest-frame color-magnitude diagrams at 0.1 < z < 1.2. We find that {approx}20% of the red sequence galaxies show evidence of dust emission at longer rest-frame wavelengths. The reduced images, photometric catalog, and photometric redshifts are provided through the public MUSYC Web site.

  16. Deep structure of the Texas Gulf passive margin and its Ouachita-Precambrian basement: Results of the COCORP San Marcos arch survey

    SciTech Connect

    Culotta, R.; Latham, T.; Oliver, J.; Brown, L.; Kaufman, S. ); Sydow, M. )

    1992-02-01

    This COCORP deep seismic survey provides a comprehensive image of the southeast-Texas part of the Gulf passive margin and its accreted Ouachita arc foundation. Beneath the updip limit of the Cenozoic sediment wedge, a prominent antiformal structure is imaged within the interior zone of the buried late Paleozoic Ouachita orogen. The structure appears to involve Precambrian Grenville basement. The crest of the antiform is coincident with the Cretaceous-Tertiary Luling-Mexia-Talco fault zone. Some of these faults dip to the northwest, counter to the general regional pattern of down-to-the-basin faulting, and appear to sole into the top of the antiform, suggesting that the Ouachita structure has been reactivated as a hingeline to the subsiding passive margin. The antiform may be tied via this fault system and the Ouachita gravity gradient to the similar Devils River, Waco, and Benton uplifts, interpreted as Precambrian basement-cored massifs. Above the Paleozoic sequence, a possible rift-related graben is imaged near the updip limit of Jurassic salt. Paleoshelf edges of the major Tertiary depositional sequences are marked by expanded sections disrupted by growth faults and shale diapirs. Within the Wilcox Formation, the transect crosses the mouth of the 900-m-deep Yoakum Canyon, a principal pathway of sediment delivery from the Laramide belt to the Gulf. Beneath the Wilcox, the Comanchean (Lower Cretaceous) shelf edge, capped by the Stuart City reef, is imaged as a pronounced topographic break onlapped by several moundy sediment packages. Because this segment of the line parallels strike, the topographic break may be interpreted as a 2,000-m-deep embayment in the Cretaceous shelf-edge, and possibly a major submarine canyon older and deeper than the Yoakum Canyon.

  17. A Determination of the Intergalactic Redshift Dependent UV-Optical-NIR Photon Density Using Deep Galaxy Survey Data and the Gamma-ray Opacity of the Universe

    NASA Technical Reports Server (NTRS)

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

    2012-01-01

    We calculate the intensity and photon spectrum of the intergalactic background light (IBL) as a function of redshift using an approach based on observational data obtained in many different wavelength bands from local to deep galaxy surveys. This allows us to obtain an empirical determination of the IBL and to quantify its observationally based uncertainties. Using our results on the IBL, we then place 68% confidence upper and lower limits on the opacity of the universe to gamma-rays, free of the theoretical assumptions that were needed for past calculations. We compare our results with measurements of the extragalactic background light and upper limits obtained from observations made by the Fermi Gamma-ray Space Telescope.

  18. Ages and magnetic structures of the South China Sea constrained by deep tow magnetic surveys and IODP Expedition 349

    NASA Astrophysics Data System (ADS)

    Li, Chun-Feng; Xu, Xing; Lin, Jian; Sun, Zhen; Zhu, Jian; Yao, Yongjian; Zhao, Xixi; Liu, Qingsong; Kulhanek, Denise K.; Wang, Jian; Song, Taoran; Zhao, Junfeng; Qiu, Ning; Guan, Yongxian; Zhou, Zhiyuan; Williams, Trevor; Bao, Rui; Briais, Anne; Brown, Elizabeth A.; Chen, Yifeng; Clift, Peter D.; Colwell, Frederick S.; Dadd, Kelsie A.; Ding, Weiwei; Almeida, Iván. Hernández; Huang, Xiao-Long; Hyun, Sangmin; Jiang, Tao; Koppers, Anthony A. P.; Li, Qianyu; Liu, Chuanlian; Liu, Zhifei; Nagai, Renata H.; Peleo-Alampay, Alyssa; Su, Xin; Tejada, Maria Luisa G.; Trinh, Hai Son; Yeh, Yi-Ching; Zhang, Chuanlun; Zhang, Fan; Zhang, Guo-Liang

    2014-12-01

    analyses of deep tow magnetic anomalies and International Ocean Discovery Program Expedition 349 cores show that initial seafloor spreading started around 33 Ma in the northeastern South China Sea (SCS), but varied slightly by 1-2 Myr along the northern continent-ocean boundary (COB). A southward ridge jump of ˜20 km occurred around 23.6 Ma in the East Subbasin; this timing also slightly varied along the ridge and was coeval to the onset of seafloor spreading in the Southwest Subbasin, which propagated for about 400 km southwestward from ˜23.6 to ˜21.5 Ma. The terminal age of seafloor spreading is ˜15 Ma in the East Subbasin and ˜16 Ma in the Southwest Subbasin. The full spreading rate in the East Subbasin varied largely from ˜20 to ˜80 km/Myr, but mostly decreased with time except for the period between ˜26.0 Ma and the ridge jump (˜23.6 Ma), within which the rate was the fastest at ˜70 km/Myr on average. The spreading rates are not correlated, in most cases, to magnetic anomaly amplitudes that reflect basement magnetization contrasts. Shipboard magnetic measurements reveal at least one magnetic reversal in the top 100 m of basaltic layers, in addition to large vertical intensity variations. These complexities are caused by late-stage lava flows that are magnetized in a different polarity from the primary basaltic layer emplaced during the main phase of crustal accretion. Deep tow magnetic modeling also reveals this smearing in basement magnetizations by incorporating a contamination coefficient of 0.5, which partly alleviates the problem of assuming a magnetic blocking model of constant thickness and uniform magnetization. The primary contribution to magnetic anomalies of the SCS is not in the top 100 m of the igneous basement.

  19. Deep 610-MHz Giant Metrewave Radio Telescope observations of the Spitzer extragalactic First Look Survey field - III. The radio properties of infrared-faint radio sources

    NASA Astrophysics Data System (ADS)

    Garn, Timothy; Alexander, Paul

    2008-12-01

    Infrared-faint radio sources (IFRSs) are a class of source which are bright at radio frequencies, but do not appear in deep infrared images. We report the detection of 14 IFRSs within the Spitzer extragalactic First Look Survey field, eight of which are detected near to the limiting magnitude of a deep R-band image of the region, at R ~ 24.5. Sensitive Spitzer Space Telescope images are stacked in order to place upper limits on their mid-infrared flux densities, and using recent 610-MHz and 1.4-GHz observations we find that they have spectral indices which vary between α = 0.05 and 1.38, where we define α such that Sν = S0ν-α, and should not be thought of as a single source population. We place constraints on the luminosity and linear size of these sources, and through comparison with well-studied local objects in the Revised Revised Third Cambridge catalogue demonstrate that they can be modelled as being compact (<20 kpc) Fanaroff-Riley type II (FRII) radio galaxies located at high redshift (z ~ 4).

  20. The Hubble Space Telescope Medium Deep Survey with the Wide Field and Planetary Camera. 1: Methodology and results on the field near 3C 273

    NASA Technical Reports Server (NTRS)

    Griffiths, R. E.; Ratnatunga, K. U.; Neuschaefer, L. W.; Casertano, S.; Im, M.; Wyckoff, E. W.; Ellis, R. S.; Gilmore, G. F.; Elson, R. A. W.; Glazebrook, K.

    1994-01-01

    We present results from the Medium Deep Survey (MDS), a Key Project using the Hubble Space Telescope (HST). Wide Field Camera (WFC) images of random fields have been taken in 'parallel mode' with an effective resolution of 0.2 sec full width at half maximum (FWHM) in the V(F555W) and I(F785LP) filters. The exposures presented here were targeted on a field away from 3C 273, and resulted in approximately 5 hr integration time in each filter. Detailed morphological structure is seen in galaxy images with total integrated magnitudes down to V approximately = 22.5 and I approximately = 21.5. Parameters are estimated that best fit the observed galaxy images, and 143 objects are identified (including 23 stars) in the field to a fainter limiting magnitude of I approximately = 23.5. We outline the extragalactic goals of the HST Medium Deep Survey, summarize our basic data reduction procedures, and present number (magnitude) counts, a color-magnitude diagram for the field, surface brightness profiles for the brighter galaxies, and best-fit half-light radii for the fainter galaxies as a function of apparent magnitude. A median galaxy half-light radius of 0.4 sec is measured, and the distribution of galaxy sizes versus magnitude is presented. We observe an apparent deficit of galaxies with half-light radii between approximately 0.6 sec and 1.5 sec, with respect to standard no-evolution or mild evolution cosmological models. An apparent excess of compact objects (half-light radii approximately 0.1 sec) is also observed with respect to those models. Finally, we find a small excess in the number of faint galaxy pairs and groups with respect to a random low-redshift field sample.

  1. SXDF-ALMA 2 arcmin2 deep survey: Resolving and characterizing the infrared extragalactic background light down to 0.5 mJy

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Yuki; Tamura, Yoichi; Kohno, Kotaro; Aretxaga, Itziar; Dunlop, James S.; Hatsukade, Bunyo; Hughes, David; Ikarashi, Soh; Ishii, Shun; Ivison, Rob J.; Izumi, Takuma; Kawabe, Ryohei; Kodama, Tadayuki; Lee, Minju; Makiya, Ryu; Matsuda, Yuichi; Nakanishi, Kouichiro; Ohta, Kouji; Rujopakarn, Wiphu; Tadaki, Ken-ichi; Umehata, Hideki; Wang, Wei-Hao; Wilson, Grant W.; Yabe, Kiyoto; Yun, Min S.

    2016-10-01

    We present a multiwavelength analysis of five submillimeter sources (S1.1mm = 0.54-2.02 mJy) that were detected during our 1.1 mm deep continuum survey in the Subaru/XMM-Newton Deep Survey Field (SXDF)-UDS-CANDELS field (2 arcmin2, 1σ = 0.055 mJy beam-1) using the Atacama Large Millimeter/submillimeter Array (ALMA). The two brightest sources correspond to a known single-dish (AzTEC) selected bright submillimeter galaxy (SMG), whereas the remaining three are faint SMGs newly uncovered by ALMA. If we exclude the two brightest sources, the contribution of the ALMA-detected faint SMGs to the infrared extragalactic background light is estimated to be ˜ 4.1^{+5.4}_{-3.0}Jy deg-2, which corresponds to ˜ 16^{+22}_{-12}% of the infrared extragalactic background light. This suggests that their contribution to the infrared extragalactic background light is as large as that of bright SMGs. We identified multiwavelength counterparts of the five ALMA sources. One of the sources (SXDF-ALMA3) is extremely faint in the optical to near-infrared region despite its infrared luminosity (L_IR˜eq 1× 10^{12} L_{⊙} or SFR ≃ 100 M⊙ yr-1). By fitting the spectral energy distributions at the optical-to-near-infrared wavelengths of the remaining four ALMA sources, we obtained the photometric redshifts (zphoto) and stellar masses (M*): zphoto ≃ 1.3-2.5, M* ≃ (3.5-9.5) × 1010 M⊙. We also derived their star formation rates (SFRs) and specific SFRs as ≃30-200 M⊙ yr-1 and ≃0.8-2 Gyr-1, respectively. These values imply that they are main sequence star-forming galaxies.

  2. The Deep Look at the Hard X-Ray Sky: The Swift-INTEGRAL X-Ray (SIX) Survey

    NASA Astrophysics Data System (ADS)

    Bottacini, Eugenio; Ajello, Marco; Greiner, Jochen

    2012-08-01

    The supermassive black holes at the center of active galactic nuclei (AGNs) are surrounded by obscuring matter that can block nuclear radiation. Depending on the amount of blocked radiation, the flux from the AGN can be too faint to be detected by currently flying hard X-ray (above 15 keV) missions. At these energies only ~1% of the intensity of the cosmic X-ray background (CXB) can be resolved into point-like sources that are AGNs. In this work, we address the question of undetected sources contributing to the CXB with a very sensitive and new hard X-ray survey: the Swift-INTEGRAL X-ray survey, which is obtained with the new approach of combining the Swift/BAT and INTEGRAL/IBIS X-ray observations. We merge the observations of both missions, which enhances the exposure time and reduces systematic uncertainties. As a result, we obtain a new survey over a wide sky area of 6200 deg2 that is more sensitive than the surveys of Swift/BAT or INTEGRAL/IBIS alone. Our sample comprises 113 sources: 86 AGNs (Seyfert-like and blazars), 5 galaxies, 2 clusters of galaxies, 3 Galactic sources, 3 previously detected unidentified X-ray sources, and 14 unidentified sources. The scientific outcome from the study of the sample has been properly addressed to study the evolution of AGNs at redshift below 0.4. We do not find any evolution using the 1/V max method. Our sample of faint sources is a suitable target for the new generation hard X-ray telescopes with focusing techniques.

  3. THE DEEP LOOK AT THE HARD X-RAY SKY: THE SWIFT-INTEGRAL X-RAY (SIX) SURVEY

    SciTech Connect

    Bottacini, Eugenio; Ajello, Marco

    2012-08-01

    The supermassive black holes at the center of active galactic nuclei (AGNs) are surrounded by obscuring matter that can block nuclear radiation. Depending on the amount of blocked radiation, the flux from the AGN can be too faint to be detected by currently flying hard X-ray (above 15 keV) missions. At these energies only {approx}1% of the intensity of the cosmic X-ray background (CXB) can be resolved into point-like sources that are AGNs. In this work, we address the question of undetected sources contributing to the CXB with a very sensitive and new hard X-ray survey: the Swift-INTEGRAL X-ray survey, which is obtained with the new approach of combining the Swift/BAT and INTEGRAL/IBIS X-ray observations. We merge the observations of both missions, which enhances the exposure time and reduces systematic uncertainties. As a result, we obtain a new survey over a wide sky area of 6200 deg{sup 2} that is more sensitive than the surveys of Swift/BAT or INTEGRAL/IBIS alone. Our sample comprises 113 sources: 86 AGNs (Seyfert-like and blazars), 5 galaxies, 2 clusters of galaxies, 3 Galactic sources, 3 previously detected unidentified X-ray sources, and 14 unidentified sources. The scientific outcome from the study of the sample has been properly addressed to study the evolution of AGNs at redshift below 0.4. We do not find any evolution using the 1/V{sub max} method. Our sample of faint sources is a suitable target for the new generation hard X-ray telescopes with focusing techniques.

  4. The VIMOS Ultra Deep Survey first data release: Spectra and spectroscopic redshifts of 698 objects up to zspec 6 in CANDELS

    NASA Astrophysics Data System (ADS)

    Tasca, L. A. M.; Le Fèvre, O.; Ribeiro, B.; Thomas, R.; Moreau, C.; Cassata, P.; Garilli, B.; Le Brun, V.; Lemaux, B. C.; Maccagni, D.; Pentericci, L.; Schaerer, D.; Vanzella, E.; Zamorani, G.; Zucca, E.; Amorin, R.; Bardelli, S.; Cassarà, L. P.; Castellano, M.; Cimatti, A.; Cucciati, O.; Durkalec, A.; Fontana, A.; Giavalisco, M.; Grazian, A.; Hathi, N. P.; Ilbert, O.; Paltani, S.; Pforr, J.; Scodeggio, M.; Sommariva, V.; Talia, M.; Tresse, L.; Vergani, D.; Capak, P.; Charlot, S.; Contini, T.; de la Torre, S.; Dunlop, J.; Fotopoulou, S.; Guaita, L.; Koekemoer, A.; López-Sanjuan, C.; Mellier, Y.; Salvato, M.; Scoville, N.; Taniguchi, Y.; Wang, P. W.

    2017-04-01

    This paper describes the first data release (DR1) of the VIMOS Ultra Deep Survey (VUDS). The VUDS-DR1 is the release of all low-resolution spectroscopic data obtained in 276.9 arcmin2 of the CANDELS-COSMOS and CANDELS-ECDFS survey areas, including accurate spectroscopic redshifts zspec and individual spectra obtained with VIMOS on the ESO-VLT. A total of 698 objects have a measured redshift, with 677 galaxies, two type-I AGN, and a small number of 19 contaminating stars. The targets of the spectroscopic survey are selected primarily on the basis of their photometric redshifts to ensure a broad population coverage. About 500 galaxies have zspec > 2, 48of which have zspec > 4; the highest reliable redshifts reach beyond zspec = 6. This data set approximately doubles the number of galaxies with spectroscopic redshifts at z > 3 in these fields. We discuss the general properties of the VUDS-DR1 sample in terms of the spectroscopic redshift distribution, the distribution of Lyman-α equivalent widths, and physical properties including stellar masses M⋆ and star formation rates derived from spectral energy distribution fitting with the knowledge of zspec. We highlight the properties of the most massive star-forming galaxies, noting the wide range in spectral properties, with Lyman-α in emission or in absorption, and in imaging properties with compact, multi-component, or pair morphologies. We present the catalogue database and data products. All VUDS-DR1 data are publicly available and can be retrieved from a dedicated query-based database. Future VUDS data releases will follow this VUDS-DR1 to give access to the spectra and associated measurement of 8000 objects in the full 1 square degree of the VUDS survey. Based on data obtained with the European Southern Observatory Very Large Telescope, Paranal, Chile, under Large Program 185.A-0791. http://cesam.lam.fr/vuds

  5. The Infrared Medium-deep Survey. III. Survey of Luminous Quasars at 4.7 ≤ z ≤ 5.4

    NASA Astrophysics Data System (ADS)

    Jeon, Yiseul; Im, Myungshin; Kim, Dohyeong; Kim, Yongjung; Jun, Hyunsung David; Pak, Soojong; Taak, Yoon Chan; Baek, Giseon; Choi, Changsu; Choi, Nahyun; Hong, Jueun; Hyun, Minhee; Ji, Tae-Geun; Karouzos, Marios; Kim, Duho; Kim, Jae-Woo; Kim, Ji Hoon; Kim, Minjin; Kim, Sanghyuk; Lee, Hye-In; Lee, Seong-Kook; Park, Won-Kee; Park, Woojin; Yoon, Yongmin

    2017-08-01

    We present the first results of our survey for high-redshift quasars at 5≲ z≲ 5.7. The search for quasars in this redshift range has been known to be challenging due to the limitations of the filter sets used in previous studies. We conducted a quasar survey for two specific redshift ranges, 4.60 ≤ z ≤ 5.40 and 5.50 ≤ z ≤ 6.05, using multi-wavelength data that include observations made with custom-designed filters, is and iz. Using these filters and a new selection technique, we were able to reduce the fraction of interlopers. Through optical spectroscopy, we confirmed six quasars at 4.7 ≤ z ≤ 5.4 with -27.4< {M}1450< -26.4 that recently were discovered independently by another group. We estimated black hole masses and Eddington ratios of four of these quasars from optical and near-infrared spectra, and found that these quasars are undergoing nearly Eddington-limited accretion that is consistent with the rapid growth of supermassive black holes in luminous quasars at z ˜ 5. Based on observations made with ESO Telescopes at the La Silla Paranal Observatory, under programme 091.A-0878.

  6. The ATLAS 5.5 GHz survey of the extended Chandra Deep Field South: the second data release

    NASA Astrophysics Data System (ADS)

    Huynh, M. T.; Bell, M. E.; Hopkins, A. M.; Norris, R. P.; Seymour, N.

    2015-11-01

    We present a new image of the 5.5 GHz radio emission from the extended Chandra Deep Field South. Deep radio observations at 5.5 GHz were obtained in 2010 and presented in the first data release. A further 76 h of integration has since been obtained, nearly doubling the integration time. This paper presents a new analysis of all the data. The new image reaches 8.6 μJy rms, an improvement of about 40 per cent in sensitivity. We present a new catalogue of 5.5 GHz sources, identifying 212 source components, roughly 50 per cent more than were detected in the first data release. Source counts derived from this sample are consistent with those reported in the literature for S5.5 GHz > 0.1 mJy but significantly lower than published values in the lowest flux density bins (S5.5 GHz < 0.1 mJy), where we have more detected sources and improved statistical reliability. The 5.5 GHz radio sources were matched to 1.4 GHz sources in the literature and we find a mean spectral index of -0.35 ± 0.10 for S5.5 GHz > 0.5 mJy, consistent with the flattening of the spectral index observed in 5 GHz sub-mJy samples. The median spectral index of the whole sample is αmed = -0.58, indicating that these observations may be starting to probe the star-forming population. However, even at the faintest levels (0.05 < S5.5 GHz < 0.1 mJy), 39 per cent of the 5.5 GHz sources have flat or inverted radio spectra. Four flux density measurements from our data, across the full 4.5-6.5 GHz bandwidth, are combined with those from literature and we find 10 per cent of sources (S5.5 GHz ≳ 0.1 mJy) show significant curvature in their radio spectral energy distribution spanning 1.4-9 GHz.

  7. THE DEEP2 GALAXY REDSHIFT SURVEY: CLUSTERING DEPENDENCE ON GALAXY STELLAR MASS AND STAR FORMATION RATE AT z {approx} 1

    SciTech Connect

    Mostek, Nick; Coil, Alison L.; Cooper, Michael; Davis, Marc; Newman, Jeffrey A.; Weiner, Benjamin J.

    2013-04-10

    We present DEEP2 galaxy clustering measurements at z {approx} 1 as a function of stellar mass, star formation rate (SFR), and specific SFR (sSFR). We find a strong positive correlation between stellar mass and clustering amplitude on 1-10 h {sup -1} Mpc scales for blue, star-forming galaxies with 9.5 < log(M{sub *}/M{sub Sun }) < 11 and no dependence for red, quiescent galaxies with 10.5 < log(M{sub *}/M{sub Sun }) < 11.5. Using recently re-calibrated DEEP2 SFRs from restframe B-band magnitude and optical colors, we find that within the blue galaxy population at z {approx} 1 the clustering amplitude increases strongly with increasing SFR and decreasing sSFR. For red galaxies there is no significant correlation between clustering amplitude and either SFR or sSFR. Blue galaxies with high SFR or low sSFR are as clustered on large scales as red galaxies. We find that the clustering trend observed with SFR can be explained mostly, but not entirely, by the correlation between stellar mass and clustering amplitude for blue galaxies. We also show that galaxies above the star-forming 'main sequence' are less clustered than galaxies below the main sequence, at a given stellar mass. These results are not consistent with the high-sSFR population being dominated by major mergers. We also measure the clustering amplitude on small scales ({<=}0.3 h {sup -1} Mpc) and find an enhanced clustering signal relative to the best-fit large-scale power law for red galaxies with high stellar mass, blue galaxies with high SFR, and both red and blue galaxies with high sSFR. The increased small-scale clustering for galaxies with high sSFRs is likely linked to triggered star formation in interacting galaxies. These measurements provide strong constraints on galaxy evolution and halo occupation distribution models at z {approx} 1.

  8. VizieR Online Data Catalog: MACT survey. I. Opt. spectroscopy in Subaru Deep Field (Ly+, 2016)

    NASA Astrophysics Data System (ADS)

    Ly, C.; Malhotra, S.; Malkan, M. A.; Rigby, J. R.; Kashikawa, N.; de Los Reyes, M. A.; Rhoads, J. E.

    2016-10-01

    The primary results of this paper are based on optical spectroscopy conducted with Keck's Deep Imaging Multi-Object Spectrograph (DEIMOS) and MMT's Hectospec. In total, we obtain 3243 optical spectra for 1911 narrowband/intermediate-band excess emitters (roughly 20% of our narrowband/intermediate-band excess samples), and successfully detect emission lines to determine redshift for 1493 galaxies or 78% of the targeted sample. The MMT observations were conducted on 2008 March 13, 2008 April 10-11, 2008 April 14, 2014 February 27-28, 2014 March 25, and 2014 March 28-31, and correspond to the equivalent of three full nights. The Keck observations were conducted on 2004 April 23-24, 2008 May 01-02, 2009 April 25-28, 2014 May 02, and 2015 March 17/19/26. The majority of the observations were obtained in 2014-2015. The 2004 spectroscopic observations have been discussed in Kashikawa et al. (2006, J/ApJ/648/7) and Ly07 (J/ApJ/657/738), and the 2008-2009 data have been discussed in Kashikawa et al. (2011ApJ...734..119K). See section 2.2 for further details. The Subaru Deep Field (SDF) has been imaged with: (1) GALEX in both the FUV and NUV bands; (2) KPNO's Mayall telescope using MOSAIC in U; (3) Subaru telescope with Suprime-Cam in 14 bands (BVRci'z'zbzr), and five narrowband and two intermediate-band filters); (4) KPNO's Mayall telescope using NEWFIRM in H; (5) UKIRT using WFCAM in J and K; and (6) Spitzer in the four IRAC bands (3.6, 4.5, 5.8, and 8.0um). Most of these imaging data have been discussed in Ly et al. (2011ApJ...735...91L), except for the WFCAM J-band data and most of the NEWFIRM H-band data. The more recent NEWFIRM imaging data were acquired on 2012 March 06-07 and 2013 March 27-30. The WFCAM data were obtained on 2005 April 14-15, 2010 March 15-20, and 2010 April 22-23. See section 4.4 for further details. (11 data files).

  9. LOFAR/H-ATLAS: a deep low-frequency survey of the Herschel-ATLAS North Galactic Pole field

    NASA Astrophysics Data System (ADS)

    Hardcastle, M. J.; Gürkan, G.; van Weeren, R. J.; Williams, W. L.; Best, P. N.; de Gasperin, F.; Rafferty, D. A.; Read, S. C.; Sabater, J.; Shimwell, T. W.; Smith, D. J. B.; Tasse, C.; Bourne, N.; Brienza, M.; Brüggen, M.; Brunetti, G.; Chyży, K. T.; Conway, J.; Dunne, L.; Eales, S. A.; Maddox, S. J.; Jarvis, M. J.; Mahony, E. K.; Morganti, R.; Prandoni, I.; Röttgering, H. J. A.; Valiante, E.; White, G. J.

    2016-10-01

    We present Low-Frequency Array (LOFAR) High-Band Array observations of the Herschel-ATLAS North Galactic Pole survey area. The survey we have carried out, consisting of four pointings covering around 142 deg2 of sky in the frequency range 126-173 MHz, does not provide uniform noise coverage but otherwise is representative of the quality of data to be expected in the planned LOFAR wide-area surveys, and has been reduced using recently developed `facet calibration' methods at a resolution approaching the full resolution of the data sets (˜10 × 6 arcsec) and an rms off-source noise that ranges from 100 μJy beam-1 in the centre of the best fields to around 2 mJy beam-1 at the furthest extent of our imaging. We describe the imaging, cataloguing and source identification processes, and present some initial science results based on a 5σ source catalogue. These include (i) an initial look at the radio/far-infrared correlation at 150 MHz, showing that many Herschel sources are not yet detected by LOFAR; (ii) number counts at 150 MHz, including, for the first time, observational constraints on the numbers of star-forming galaxies; (iii) the 150-MHz luminosity functions for active and star-forming galaxies, which agree well with determinations at higher frequencies at low redshift, and show strong redshift evolution of the star-forming population; and (iv) some discussion of the implications of our observations for studies of radio galaxy life cycles.

  10. Barcoding Beetles: A Regional Survey of 1872 Species Reveals High Identification Success and Unusually Deep Interspecific Divergences

    PubMed Central

    Pentinsaari, Mikko; Hebert, Paul D. N.; Mutanen, Marko

    2014-01-01

    With 400 K described species, beetles (Insecta: Coleoptera) represent the most diverse order in the animal kingdom. Although the study of their diversity currently represents a major challenge, DNA barcodes may provide a functional, standardized tool for their identification. To evaluate this possibility, we performed the first comprehensive test of the effectiveness of DNA barcodes as a tool for beetle identification by sequencing the COI barcode region from 1872 North European species. We examined intraspecific divergences, identification success and the effects of sample size on variation observed within and between species. A high proportion (98.3%) of these species possessed distinctive barcode sequence arrays. Moreover, the sequence divergences between nearest neighbor species were considerably higher than those reported for the only other insect order, Lepidoptera, which has seen intensive analysis (11.99% vs up to 5.80% mean NN divergence). Although maximum intraspecific divergence increased and average divergence between nearest neighbors decreased with increasing sampling effort, these trends rarely hampered identification by DNA barcodes due to deep sequence divergences between most species. The Barcode Index Number system in BOLD coincided strongly with known species boundaries with perfect matches between species and BINs in 92.1% of all cases. In addition, DNA barcode analysis revealed the likely occurrence of about 20 overlooked species. The current results indicate that DNA barcodes distinguish species of beetles remarkably well, establishing their potential to provide an effective identification tool for this order and to accelerate the discovery of new beetle species. PMID:25255319

  11. Absolute magnetization of the seafloor at a basalt-hosted hydrothermal site: Insights from a deep-sea submersible survey

    NASA Astrophysics Data System (ADS)

    Szitkar, Florent; Dyment, Jérôme; Fouquet, Yves; Choi, Yujin; Honsho, Chie

    2015-02-01

    The analysis of high-resolution vector magnetic data acquired by deep-sea submersibles (DSSs) requires the development of specific approaches adapted to their uneven tracks. We present a method that takes advantage of (1) the varying altitude of the DSS above the seafloor and (2) high-resolution multibeam bathymetric data acquired separately, at higher altitude, by an Autonomous Underwater Vehicle, to estimate the absolute magnetization intensity and the magnetic polarity of the shallow subseafloor along the DSS path. We apply this method to data collected by DSS Nautile on a small active basalt-hosted hydrothermal site. The site is associated with a lack of magnetization, in agreement with previous findings at the same kind of sites: the contrast between nonmagnetic sulfide deposits/stockwork zone and strongly magnetized basalt is sufficient to explain the magnetic signal observed at such a low altitude. Both normal and reversed polarities are observed in the lava flows surrounding the site, suggesting complex history of accumulating volcanic flows.

  12. A Large-Scale Super-Structure at z=0.65 in the UKIDSS Ultra-Deep Survey Field

    NASA Astrophysics Data System (ADS)

    Galametz, Audrey; Candels Clustering Working Group

    2017-07-01

    In hierarchical structure formation scenarios, galaxies accrete along high density filaments. Superclusters represent the largest density enhancements in the cosmic web with scales of 100 to 200 Mpc. As they represent the largest components of LSS, they are very powerful tools to constrain cosmological models. Since they also offer a wide range of density, from infalling group to high density cluster core, they are also the perfect laboratory to study the influence of environment on galaxy evolution. I will present a newly discovered large scale structure at z=0.65 in the UKIDSS UDS field. Although statistically predicted, the presence of such structure in UKIDSS, one of the most extensively covered and studied extragalactic field, remains a serendipity. Our follow-up confirmed more than 15 group members including at least three galaxy clusters with M200 10^14Msol . Deep spectroscopy of the quiescent core galaxies reveals that the most massive structure knots are at very different formation stage with a range of red sequence properties. Statistics allow us to map formation age across the structure denser knots and identify where quenching is most probably occurring across the LSS. Spectral diagnostics analysis also reveals an interesting population of transition galaxies we suspect are transforming from star-forming to quiescent galaxies.

  13. Bacteria as part of bioluminescence emission at the deep ANTARES station (North-Western Mediterranean Sea) during a one-year survey

    NASA Astrophysics Data System (ADS)

    Martini, S.; Michotey, V.; Casalot, L.; Bonin, P.; Guasco, S.; Garel, M.; Tamburini, C.

    2016-10-01

    Bioluminescent bacteria have been studied during a one-year survey in 2011 at the deep ANTARES site (Northwestern Mediterranean Sea, 2000 m depth). The neutrino underwater telescope ANTARES, located at this station, has been used to record the bioluminescence at the same depth. Together with these data, environmental variables (potential temperature, salinity, nutrients, dissolved organic carbon and oxygen) have been characterized in water samples. The year 2011 was characterized by relatively stable conditions, as revealed by minor variability in the monitored oceanographic variables, by low bioluminescence and low current speed. This suggests weak eukaryote participation and mainly non-stimulated light emission. Hence, no processes of dense water have affected the ANTARES station during this survey. Abundance of bioluminescent bacteria belonging to Photobacterium genus, measured by qPCR of the luxF gene, ranged from 1.4×102 to 7.2×102 genes mL-1. Their effective activity was confirmed through mRNA luxF quantification. Our results reveal that bioluminescent bacteria appeared more active than the total counterpart of bacteria, suggesting an ecological benefit of this feature such as favoring interaction with macro-organisms. Moreover, these results show that part of the bioluminescence, recorded at 2000 m depth over one year, could be due to bioluminescent bacteria in stable hydrological conditions.

  14. SPLAT: Using Spectral Indices to Identify and Characterize Ultracool Stars, Brown Dwarfs and Exoplanets in Deep Surveys and as Companions to Nearby Stars

    NASA Astrophysics Data System (ADS)

    Aganze, Christian; Burgasser, Adam J.; Martin, Eduardo; Konopacky, Quinn; Masters, Daniel C.

    2016-06-01

    The majority of ultracool dwarf stars and brown dwarfs currently known were identified in wide-field red optical and infrared surveys, enabling measures of the local, typically isolated, population in a relatively shallow (<100 pc radius) volume. Constraining the properties of the wider Galactic population (scale height, radial distribution, Population II sources), and close brown dwarf and exoplanet companions to nearby stars, requires specialized instrumentation, such as high-contrast, coronagraphic spectrometers (e.g., Gemini/GPI, VLT/Sphere, Project 1640); and deep spectral surveys (e.g., HST/WFC3 parallel fields, Euclid). We present a set of quantitative methodologies to identify and robustly characterize sources for these specific populations, based on templates and tools developed as part of the SpeX Prism Library Analysis Toolkit. In particular, we define and characterize specifically-tuned sets spectral indices that optimize selection of cool dwarfs and distinguish rare populations (subdwarfs, young planetary-mass objects) based on low-resolution, limited-wavelength-coverage spectral data; and present a template-matching classification method for these instruments. We apply these techniques to HST/WFC3 parallel fields data in the WISPS and HST-3D programs, where our spectral index set allows high completeness and low contamination for searches of late M, L and T dwarfs to distances out to ~3 kpc.The material presented here is based on work supported by the National Aeronautics and Space Administration under Grant No. NNX15AI75G.

  15. Preliminary results of the Deep Freeze 85 marine geologic and geophysical survey of the Antarctic Peninsula continental shelf and South Orkney Plateau

    SciTech Connect

    Anderson, J.B.; Bartek, L.; Griffith, T.; Herron, M.; Kennedy, D.; Singer, J.; Smith, M.

    1985-01-01

    Seismic profiles from the South Orkney Plateau show a relatively thick (>0.7 seconds), laminated sequence resting on block faulted acoustic basement and deformed strata. This represents the rifting of the plateau from the Antarctic Peninsula and subsequent pelagic sedimentation. A glacial erosional surface and associated glacial trough were identified on the platform, and possible basal till collected in at least one piston core. Seismic lines from the continental shelf north of the South Shetland Plateau show gently folded reflectors that have been truncated by a widespread erosional unconformity and probable moraines situated near the shelf edge. A line across the Bransfield Strait, a modern back-arc basin, shows the structural features of the basin and thick (>1.0 second) laminated sediments within the center of the basin. One of several deep channels which dissect the shelf was surveyed, but the origin of these features remains uncertain. Geophysical data and piston cores were acquired in several of the bays and fjords of the peninsula region. This is the first detailed survey of Antarctic bays and fjords. The preliminary results show striking differences in sedimentation between Antarctic fjords and those of Arctic and Subarctic regions, the most important difference being the limited role of meltwater runoff in the supply of sediment to Antarctic fjords.

  16. A deep x ray survey in the Lockman hole and the soft x ray log N - log S

    NASA Technical Reports Server (NTRS)

    Hasinger, G.; Burg, R.; Giacconi, R.; Hartner, G.; Schmidt, M.; Truemper, J.; Zamorani, G.

    1992-01-01

    The longest pointed observation (152 ksec) with the Rosat position sensitive proportional counter in the direction of the absolutely lowest neutral hydrogen column density is discussed. 26 shallower fields from the Rosat medium sensivity survey are analyzed. 1176 X-ray sources were detected in at least one Rosat energy band in these fields covering a total solid angle of 9.3 deg; 661 of these sources constitute a statistically complete sample detected in the hard band with 0.5 to 2 keV fluxes greater than 2.5 times 10 to the power of minus 15 erg/sq cm s. The faintest limiting flux of the survey is analyzed. Detailed simulations show that confusion effects and other selection biases are relatively small and can be corrected for in the sample. From an analysis in the Lockman field, a best fit slope of approximately 1.8 is found for the extrapolation of the differential X-ray counts below 2.5 times 10 to the power of minus 15 erg/sq cm s. On the basis of this analysis an upper limit of approximately 25% can be found for a truly diffuse background component in the Rosat hard band.

  17. Mud volcano field seaward of the Barbados Accretionary Complex: A deep-towed side scan sonar survey

    NASA Astrophysics Data System (ADS)

    Henry, Pierre; Le Pichon, Xavier; Lallemant, Siegfried; Foucher, Jean-Paul; Westbrook, Graham; Hobart, Michael

    1990-06-01

    A 30 km2 diapiric field has been identified near 13°50'N up to 12 km seaward of the deformation front of the Barbados accretionary complex. Using a deep-towed side scan sonar with a 3.5-kHz profiler, we identified 31 different diapiric structures. Based on seismic stratigraphy, we show that this field has been active for 200,000 years and that it is a transient feature triggered by the seaward propagation of the high pore fluid pressure associated with the décollement beneath the accretionary complex. Both basement and décollement in this area are anomalously shallow due to the presence of a N110° basement ridge. The height of the diapirs above seafloor does not exceed 40-50 m and can be related to the pressure head of the mud below the décollement. Two types of structures are identified: mud volcanoes and massively emplaced diapirs and ridges on the one hand, enigmatic circular very flat mud pies and conical mounds on the other hand. The second type of structures has steeper slopes and appears to be associated with very active venting, as confirmed by a submersible exploration reported in a companion paper (Le Pichon et al., this issue (b)). The venting results in the formation of a stiff carbonate crust and of large subsiding basins around the mud pies. Continuous active fluid expulsion through these structures indicates that an efficient piping system still connects them to the zone of anomalously high pore pressure below the protodécollement.

  18. Probing the Physical Properties of High Redshift Optically Obscured Galaxies in the Bootes NOAO Deep Wide Field Survey using the Infrared Spectrograph on Spitzer

    NASA Astrophysics Data System (ADS)

    Higdon, S. J. U.; Weedman, D.; Higdon, J. L.; Houck, J. R.; Soifer, B. T.; Armus, L.; Charmandaris, V.; Herter, T. L.; Brandl, B. R.; Brown, M. J. I.; Dey, A.; Jannuzi, B.; Le Floc'h, E.; Rieke, M.

    2004-12-01

    We have surveyed a field covering 8.4 degrees2 within the NOAO Deep Wide Field Survey region in Boötes with the Multiband Imaging Photometer on the Spitzer Space Telescope to a limiting 24 um flux density of 0.3 mJy, identifying ˜ 22,000 point sources. Thirty one sources from this survey with F(24 um) > 0.75 mJy , which are optically ``invisible'' (R > 26) or very faint (I > 24) have been observed with the low-resolution modules of the Infrared Spectrograph on SST. The spectra were extracted using the IRS SMART spectral analysis package in order to optimize their signal to noise. A suite of mid-IR spectral templates of well known galaxies, observed as part of the IRS GTO program, is used to perform formal fits to the spectral energy distribution of the Boötes sources. These fits enable us to measure their redshift, to calculate the depth of the 9.7 um silicate feature along with the strength of 7.7 um PAH, as well as to estimate their bolometric luminosities. We compare the mid-IR slope, the measured PAH luminosity, and the optical depth of these sources with those of galaxies in the local Universe. As a result we are able to estimate the contribution of a dust enshrouded active nucleus to the mid-IR and bolometric luminosity of these systems. This work is based [in part] on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under NASA contract 1407. Support for this work was provided by NASA through Contract Number 1257184 issued by JPL/Caltech.

  19. The VIMOS Ultra-Deep Survey: ~10 000 galaxies with spectroscopic redshifts to study galaxy assembly at early epochs 2 < z ≃ 6

    NASA Astrophysics Data System (ADS)

    Le Fèvre, O.; Tasca, L. A. M.; Cassata, P.; Garilli, B.; Le Brun, V.; Maccagni, D.; Pentericci, L.; Thomas, R.; Vanzella, E.; Zamorani, G.; Zucca, E.; Amorin, R.; Bardelli, S.; Capak, P.; Cassarà, L.; Castellano, M.; Cimatti, A.; Cuby, J. G.; Cucciati, O.; de la Torre, S.; Durkalec, A.; Fontana, A.; Giavalisco, M.; Grazian, A.; Hathi, N. P.; Ilbert, O.; Lemaux, B. C.; Moreau, C.; Paltani, S.; Ribeiro, B.; Salvato, M.; Schaerer, D.; Scodeggio, M.; Sommariva, V.; Talia, M.; Taniguchi, Y.; Tresse, L.; Vergani, D.; Wang, P. W.; Charlot, S.; Contini, T.; Fotopoulou, S.; López-Sanjuan, C.; Mellier, Y.; Scoville, N.

    2015-04-01

    We present the VIMOS Ultra Deep Survey (VUDS), a spectroscopic redshift survey of ~10 000 very faint galaxies to study the main phase of galaxy assembly in 2 < z ≃ 6. The survey covers 1 deg2 in three separate fields: COSMOS, ECDFS, and VVDS-02h, with the selection of targets based on an inclusive combination of photometric redshifts and colour properties. Spectra covering 3650 < λ < 9350 Å are obtained with VIMOS on the ESO-VLT with integration times of 14h. Here we present the survey strategy, target selection, data processing, and the redshift measurement process with an emphasis on the specific methods used to adapt to this high-redshift range. We discuss the spectra quality and redshift reliability and derive a success rate in redshift measurement of 91%, or 74% by limiting the dataset to the most reliable measurements, down to a limiting magnitude iAB = 25. Measurements are performed all the way down to iAB = 27. The mean redshift of the main sample is z ~ 3 and extends over a broad redshift range mainly in 2 < z < 6. At 3 < z < 5, the galaxies cover a wide range of luminosities -23 < MNUV < -20.5, stellar mass 109M⊙ < M∗ < 1011M⊙, and star formation rates 1M⊙/yr < SFR < 103M⊙/yr. We discuss the spectral properties of galaxies using individual as well asstacked spectra. The comparison between spectroscopic and photometric redshifts as well as colour selection demonstrate the effectiveness of our selection scheme. From about ~ 90% of the data analysed so far, we expect to assemble >6000 galaxies with reliable spectroscopic redshifts in 2 < z < 6 when complete. This makes the VUDS the largest survey at these redshifts and offers the opportunity for unprecedented studies of the star-forming galaxy population and its distribution in large-scale structures during the main phase of galaxy assembly. Based on data obtained with the European Southern Observatory Very Large Telescope, Paranal, Chile, under Large Program 185.A-0791.Staged releases of the

  20. AN ALMA SURVEY OF SUBMILLIMETER GALAXIES IN THE EXTENDED CHANDRA DEEP FIELD SOUTH: NEAR-INFRARED MORPHOLOGIES AND STELLAR SIZES

    SciTech Connect

    Chen, Chian-Chou; Smail, Ian; Swinbank, A. M.; Simpson, J. M.; Ma, Cheng-Jiun; Alexander, D. M.; Danielson, A. L. R.; Edge, A. C.; Biggs, A. D.; Ivison, R. J.; Brandt, W. N.; Chapman, S. C.; Coppin, K. E. K.; Dannerbauer, H.; Greve, T. R.; Karim, A.; Menten, Karl M.; Schinnerer, E.; Walter, F.; Wardlow, J. L.; and others

    2015-02-01

    We analyze Hubble Space Telescope WFC3/H {sub 160}-band observations of a sample of 48 Atacama Large Millimeter/submillimeter Array detected submillimeter galaxies (SMGs) in the Extended Chandra Deep Field South field, to study their stellar morphologies and sizes. We detect 79% ± 17% of the SMGs in the H {sub 160}-band imaging with a median sensitivity of 27.8 mag, and most (80%) of the nondetections are SMGs with 870 μm fluxes of S {sub 870} < 3 mJy. With a surface brightness limit of μ {sub H} ∼ 26 mag arcsec{sup –2}, we find that 82% ± 9% of the H {sub 160}-band-detected SMGs at z = 1-3 appear to have disturbed morphologies, meaning they are visually classified as either irregulars or interacting systems, or both. By determining a Sérsic fit to the H {sub 160} surface brightness profiles, we derive a median Sérsic index of n = 1.2 ± 0.3 and a median half-light radius of r{sub e} = 4.4{sub −0.5}{sup +1.1} kpc for our SMGs at z = 1-3. We also find significant displacements between the positions of the H {sub 160} component and 870 μm emission in these systems, suggesting that the dusty starburst regions and less-obscured stellar distribution are not colocated. We find significant differences in the sizes and the Sérsic index between our z = 2-3 SMGs and z ∼ 2 quiescent galaxies, suggesting that a major transformation of the stellar light profile is needed in the quenching processes if SMGs are progenitors of the red-and-dead z ∼ 2 galaxies. Given the short-lived nature of SMGs, we postulate that the majority of the z = 2-3 SMGs with S {sub 870} ≳ 2 mJy are early/mid-stage major mergers.

  1. Comoving Space Density and Obscured Fraction of High-redshift Active Galactic Nuclei in the Subaru/XMM-Newton Deep Survey

    NASA Astrophysics Data System (ADS)

    Hiroi, Kazuo; Ueda, Yoshihiro; Akiyama, Masayuki; Watson, Mike G.

    2012-10-01

    We study the comoving space density of X-ray-selected luminous active galactic nuclei (AGNs) and the obscured AGN fraction at high redshifts (3 < z < 5) in the Subaru/XMM-Newton Deep Survey field. From an X-ray source catalog with high completeness of optical identification thanks to deep optical images, we select a sample of 30 AGNs at z > 3 with intrinsic (de-absorbed and rest-frame 2-10 keV) luminosities of L X = 1044-45 erg s-1 detected in the 0.5-2 keV band, consisting of 20 and 10 objects with spectroscopic and photometric redshifts, respectively. Utilizing the 1/V max method, we confirm that the comoving space density of luminous AGNs decreases with redshift above z > 3. When combined with the Chandra-COSMOS result of Civano et al., the density decline of AGNs with L X = 1044-45 erg s-1 is well represented by a power law of (1 + z)-6.2 ± 0.9. We also determine the fraction of X-ray obscured AGNs with N H > 1022 cm-2 in the Compton-thin population to be 0.54+0.17 - 0.19, by carefully taking into account observational biases including the effects of photon statistics for each source. This result is consistent with an independent determination of the type-2 AGN fraction based on optical properties, for which the fraction is found to be 0.59 ± 0.09. Comparing our result with that obtained in the local universe, we conclude that the obscured fraction of luminous AGNs increases significantly from z = 0 to z > 3 by a factor of 2.5 ± 1.1. Based in part on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan.

  2. New constraints on the average escape fraction of Lyman continuum radiation in z 4 galaxies from the VIMOS Ultra Deep Survey (VUDS)

    NASA Astrophysics Data System (ADS)

    Marchi, F.; Pentericci, L.; Guaita, L.; Ribeiro, B.; Castellano, M.; Schaerer, D.; Hathi, N. P.; Lemaux, B. C.; Grazian, A.; Le Fèvre, O.; Garilli, B.; Maccagni, D.; Amorin, R.; Bardelli, S.; Cassata, P.; Fontana, A.; Koekemoer, A. M.; Le Brun, V.; Tasca, L. A. M.; Thomas, R.; Vanzella, E.; Zamorani, G.; Zucca, E.

    2017-05-01

    Context. Determining the average fraction of Lyman continuum (LyC) photons escaping high redshift galaxies is essential for understanding how reionization proceeded in the z> 6 Universe. Aims: We want to measure the LyC signal from a sample of sources in the Chandra Deep Field South (CDFS) and COSMOS fields for which ultra-deep VIMOS spectroscopy as well as multi-wavelength Hubble Space Telescope (HST) imaging are available. Methods: We select a sample of 46 galaxies at z 4 from the VIMOS Ultra Deep Survey (VUDS) database, such that the VUDS spectra contain the LyC part, that is, the rest-frame range 880-910 Å. Taking advantage of the HST imaging, we apply a careful cleaning procedure and reject all the sources showing nearby clumps with different colours, that could potentially be lower-redshift interlopers. After this procedure, the sample is reduced to 33 galaxies. We measure the ratio between ionizing flux (LyC at 895 Å) and non-ionizing emission (at 1500 Å) for all individual sources. We also produce a normalized stacked spectrum of all sources. Results: Assuming an intrinsic average Lν(1470) /Lν(895) of 3, we estimate the individual and average relative escape fraction. We do not detect ionizing radiation from any individual source, although we identify a possible LyC emitter with very high Lyα equivalent width (EW). From the stacked spectrum and assuming a mean transmissivity for the sample, we measure a relative escape fraction . We also look for correlations between the limits in the LyC flux and source properties and find a tentative correlation between LyC flux and the EW of the Lyα emission line. Conclusions: Our results imply that the LyC flux emitted by V = 25-26 star-forming galaxies at z 4 is at most very modest, in agreement with previous upper limits from studies based on broad and narrow band imaging. Based on data obtained with the European Southern Observatory Very Large Telescope, Paranal, Chile, under Large Program 185.A-0791.

  3. Hubble Space Telescope Medium Deep Survey. 2: Deconvolution of Wide Field Camera field galaxy images in the 13 hour + 43 deg field

    NASA Technical Reports Server (NTRS)

    Windhorst, R. A.; Schmidtke, P. C.; Pascarelle, S. M.; Gordon, J. M.; Griffiths, R. E.; Ratnatunga, K. U.; Neuschaefer, L. W.; Ellis, R. S.; Gilmore, G.; Glazebrook, K.

    1994-01-01

    We present isophotal profiles of six faint field galaxies from some of the first deep images taken for the Hubble Space Telescope (HST) Medium Deep Survey (MDS). These have redshifts in the range z = 0.126 to 0.402. The images were taken with the Wide Field Camera (WFC) in `parallel mode' and deconvolved with the Lucy method using as the point-spread function nearby stars in the image stack. The WFC deconvolutions have a dynamic range of 16 to 20 dB (4 to 5 mag) and an effective resolution approximately less than 0.2 sec (FWHM). The multiorbit HST images allow us to trace the morphology, light profiles, and color gradients of faint field galaxies down to V approximately equal to 22 to 23 mag at sub-kpc resolution, since the redshift range covered is z = 0.1 to 0.4. The goals of the MDS are to study the sub-kpc scale morphology, light profiles, and color gradients for a large samole of faint field galaxies down to V approximately equal to 23 mag, and to trace the fraction of early to late-type galaxies as function of cosmic time. In this paper we study the brighter MDS galaxies in the 13 hour + 43 deg MDS field in detail, and investigate to what extent model fits with pure exponential disks or a(exp 1/4) bulges are justified at V approximately less than 22 mag. Four of the six field galaxies have light profiles that indicate (small) inner bulges following r(exp 1/4) laws down to 0.2 sec resolution, plus a dominant surrounding exponential disk with little or no color gradients. Two occur in a group at z = 0.401, two are barred spiral galaxies at z = 0.179 and z = 0.302, and two are rather subluminous (and edge-on) disk galaxies at z = 0.126 and z = 0.179. Our deep MDS images can detect galaxies down to V, I approximately less than 25 to 26 mag, and demonstrate the impressive potential of HST--even with its pre-refurbished optics--to resolve morphological details in galaxies at cosmologically significant distances (v approximately less than 23 mag). Since the median

  4. A Deep NuSTAR Survey of M31: Compact object types in our Nearest Neighbor Galaxy

    NASA Astrophysics Data System (ADS)

    Hornschemeier, Ann E.; Wik, Daniel R.; Yukita, Mihoko; Ptak, Andrew; Venters, Tonia M.; Lehmer, Bret; Maccarone, Thomas J.; Zezas, Andreas; Harrison, Fiona; Stern, Daniel; Williams, Benjamin F.; Vulic, Neven

    2017-08-01

    X-ray binaries (XRBs) trace young and old stellar populations in galaxies, and thus star formation rate and star formation history/stellar mass. X-ray emission from XRBs may be responsible for significant amounts of heating of the early Intergalactic Medium at Cosmic Dawn and may also play a significant role in reionization. Until recently, the E>10 keV (hard X-ray) emission from these populations could only be studied for XRBs in our own galaxy, where it is often difficult to measure accurate distances and thus luminosities. We have observed M31 in 4 NuSTAR fields for a total exposure of 1.4 Ms, covering the young stellar population in a swath of the disk (within the footprint of the Panchromatic Hubble Andromeda Treasury (PHAT) Survey) and older populations in the bulge. We detected more than 100 sources in the 4-25 keV band, where hard band (12-25 keV) emission has allowed us to discriminate between black holes and neutron stars in different accretion states. The luminosity function of the hard band detected sources are compared to Swift/BAT and INTEGRAL-derived luminosity functions of the Milky Way population, which reveals an excess of luminous sources in M31 when correcting for star formation rate and stellar mass.

  5. SELECTION OF BURST-LIKE TRANSIENTS AND STOCHASTIC VARIABLES USING MULTI-BAND IMAGE DIFFERENCING IN THE PAN-STARRS1 MEDIUM-DEEP SURVEY

    SciTech Connect

    Kumar, S.; Gezari, S.; Heinis, S.; Chornock, R.; Berger, E.; Soderberg, A.; Stubbs, C. W.; Kirshner, R. P.; Rest, A.; Huber, M. E.; Narayan, G.; Marion, G. H.; Burgett, W. S.; Foley, R. J.; Scolnic, D.; Riess, A. G.; Lawrence, A.; Smartt, S. J.; Smith, K.; Wood-Vasey, W. M.; and others

    2015-03-20

    We present a novel method for the light-curve characterization of Pan-STARRS1 Medium Deep Survey (PS1 MDS) extragalactic sources into stochastic variables (SVs) and burst-like (BL) transients, using multi-band image-differencing time-series data. We select detections in difference images associated with galaxy hosts using a star/galaxy catalog extracted from the deep PS1 MDS stacked images, and adopt a maximum a posteriori formulation to model their difference-flux time-series in four Pan-STARRS1 photometric bands g {sub P1}, r {sub P1}, i {sub P1}, and z {sub P1}. We use three deterministic light-curve models to fit BL transients; a Gaussian, a Gamma distribution, and an analytic supernova (SN) model, and one stochastic light-curve model, the Ornstein-Uhlenbeck process, in order to fit variability that is characteristic of active galactic nuclei (AGNs). We assess the quality of fit of the models band-wise and source-wise, using their estimated leave-out-one cross-validation likelihoods and corrected Akaike information criteria. We then apply a K-means clustering algorithm on these statistics, to determine the source classification in each band. The final source classification is derived as a combination of the individual filter classifications, resulting in two measures of classification quality, from the averages across the photometric filters of (1) the classifications determined from the closest K-means cluster centers, and (2) the square distances from the clustering centers in the K-means clustering spaces. For a verification set of AGNs and SNe, we show that SV and BL occupy distinct regions in the plane constituted by these measures. We use our clustering method to characterize 4361 extragalactic image difference detected sources, in the first 2.5 yr of the PS1 MDS, into 1529 BL, and 2262 SV, with a purity of 95.00% for AGNs, and 90.97% for SN based on our verification sets. We combine our light-curve classifications with their nuclear or off-nuclear host

  6. Genomic survey of premetazoans shows deep conservation of cytoplasmic tyrosine kinases and multiple radiations of receptor tyrosine kinases.

    PubMed

    Suga, Hiroshi; Dacre, Michael; de Mendoza, Alex; Shalchian-Tabrizi, Kamran; Manning, Gerard; Ruiz-Trillo, Iñaki

    2012-05-01

    The evolution of multicellular metazoans from a unicellular ancestor is one of the most important advances in the history of life. Protein tyrosine kinases play important roles in cell-to-cell communication, cell adhesion, and differentiation in metazoans; thus, elucidating their origins and early evolution is crucial for understanding the origin of metazoans. Although tyrosine kinases exist in choanoflagellates, few data are available about their existence in other premetazoan lineages. To unravel the origin of tyrosine kinases, we performed a genomic and polymerase chain reaction (PCR)-based survey of the genes that encode tyrosine kinases in the two described filasterean species, Capsaspora owczarzaki and Ministeria vibrans, the closest relatives to the Metazoa and Choanoflagellata clades. We present 103 tyrosine kinase-encoding genes identified in the whole genome sequence of C. owczarzaki and 15 tyrosine kinase-encoding genes cloned by PCR from M. vibrans. Through detailed phylogenetic analysis, comparison of the organizations of the protein domains, and resequencing and revision of tyrosine kinase sequences previously found in some whole genome sequences, we demonstrate that the basic repertoire of metazoan cytoplasmic tyrosine kinases was established before the divergence of filastereans from the Metazoa and Choanoflagellata clades. In contrast, the receptor tyrosine kinases diversified extensively in each of the filasterean, choanoflagellate, and metazoan clades. This difference in the divergence patterns between cytoplasmic tyrosine kinases and receptor tyrosine kinases suggests that receptor tyrosine kinases that had been used for receiving environmental cues were subsequently recruited as a communication tool between cells at the onset of metazoan multicellularity.

  7. Radon surveys and monitoring at active volcanoes: an open window on deep hydrothermal systems and their dynamics

    NASA Astrophysics Data System (ADS)

    Cigolini, Corrado; Laiolo, Marco; Coppola, Diego

    2017-04-01

    The behavior of fluids in hydrothermal systems is critical in volcano monitoring and geothermal prospecting. Analyzing the time series of radon emissions on active volcanoes is strategic for detecting and interpreting precursory signals of changes in volcanic activity, eventually leading to eruptions. Radon is a radioactive gas generated from the decay of U bearing rocks, soils and magmas. Although radon has been regarded as a potential precursor of earthquakes, radon anomalies appear to be better suited to forecast volcanic eruptions since we know where paroxysms may occur and we can follow the evolution of volcanic activity. Radon mapping at active volcanoes is also a reliable tool to assess diffuse and concentrated degassing as well as efficiently detecting earthquake-volcano interactions. Systematic radon monitoring has been shown to be a key factor for evaluating the rise of volcanic and hydrothermal fluids. In fact, the decay properties of radon, the duration of radon anomalies together with sampling rates may be cross-checked with the chemistry of hydrothermal fluids (and their transport properties) to constrain fluids ascent rates and to infer the permeability and porosity of rocks in sectors surrounding the active conduits. We hereby further discuss the data of radon surveys and monitoring at Somma-Vesuvius, Stromboli and La Soufrière (Guadeloupe, Lesser Antilles). The integrated analysis of seismic and geochemical data, including radon emissions, may be successfully used in testing temperature distributions and variations of porosity and permeability in volcanic hydrothermal systems and can be used as a proxy to analyze geothermal reservoirs.

  8. The MOSFIRE Deep Evolution Field (MOSDEF) Survey: Rest-frame Optical Spectroscopy for ~1500 H-selected Galaxies at 1.37 < z < 3.8

    NASA Astrophysics Data System (ADS)

    Kriek, Mariska; Shapley, Alice E.; Reddy, Naveen A.; Siana, Brian; Coil, Alison L.; Mobasher, Bahram; Freeman, William R.; de Groot, Laura; Price, Sedona H.; Sanders, Ryan; Shivaei, Irene; Brammer, Gabriel B.; Momcheva, Ivelina G.; Skelton, Rosalind E.; van Dokkum, Pieter G.; Whitaker, Katherine E.; Aird, James; Azadi, Mojegan; Kassis, Marc; Bullock, James S.; Conroy, Charlie; Davé, Romeel; Kereš, Dušan; Krumholz, Mark

    2015-06-01

    In this paper we present the MOSFIRE Deep Evolution Field (MOSDEF) survey. The MOSDEF survey aims to obtain moderate-resolution (R = 3000-3650) rest-frame optical spectra (˜3700-7000 Å) for ˜1500 galaxies at 1.37≤ z≤ 3.80 in three well-studied CANDELS fields: AEGIS, COSMOS, and GOODS-N. Targets are selected in three redshift intervals: 1.37≤ z≤ 1.70, 2.09≤ z≤ 2.61, and 2.95≤ z≤ 3.80, down to fixed {H}{AB} (F160W) magnitudes of 24.0, 24.5, and 25.0, respectively, using the photometric and spectroscopic catalogs from the 3D-HST survey. We target both strong nebular emission lines (e.g., [O ii] λ λ 3727,3730, Hβ, [O iii] λ λ 4960,5008, Hα, [N ii] λ λ 6550,6585, and [S ii] λ λ 6718,6733) and stellar continuum and absorption features (e.g., Balmer lines, Ca-ii H and K, Mgb, 4000 Å break). Here we present an overview of our survey, the observational strategy, the data reduction and analysis, and the sample characteristics based on spectra obtained during the first 24 nights. To date, we have completed 21 masks, obtaining spectra for 591 galaxies. For ˜80% of the targets we derive a robust redshift from either emission or absorption lines. In addition, we confirm 55 additional galaxies, which were serendipitously detected. The MOSDEF galaxy sample includes unobscured star-forming, dusty star-forming, and quiescent galaxies and spans a wide range in stellar mass (˜ {10}9-{10}11.5 {M}⊙ ) and star formation rate (˜ {10}0-{10}3 {M}⊙ {{yr}}-1). The spectroscopically confirmed sample is roughly representative of an H-band limited galaxy sample at these redshifts. With its large sample size, broad diversity in galaxy properties, and wealth of available ancillary data, MOSDEF will transform our understanding of the stellar, gaseous, metal, dust, and black hole content of galaxies during the time when the universe was most active.

  9. A new deep, hard X-ray survey of M31: Identifying Black Holes and Neutron Stars in the X-ray Binary Population of our Nearest Neighbor

    NASA Astrophysics Data System (ADS)

    Wik, Daniel R.; Hornschemeier, Ann E.; Yukita, Mihoko; Ptak, Andrew; Lehmer, Bret; Maccarone, Thomas J.; Antoniou, Vallia; Zezas, Andreas; Harrison, Fiona; Stern, Daniel; Venters, Tonia M.; Williams, Benjamin F.; Eracleous, Michael; Plucinsky, Paul P.; Pooley, David A.

    2016-04-01

    X-ray binaries (XRBs) trace old and new stellar populations in galaxies, and thus star formation history and star formation rate. X-ray emission from XRBs may be responsible for significant amounts of heating of the early Intergalactic Medium (IGM) at Cosmic Dawn and may also play a significant role in reionization. Until recently, the hard emission from these populations could only be studied for XRBs in our own galaxy, where it is often difficult to measure accurate distances and thus luminosities. The launch of NuSTAR, the first focusing hard X-ray observatory, has allowed us to resolve the brightest XRBs (down to LX ~ few times 10^38 erg/s) in galaxies like NGC 253, M83, and M82 up to 4 Mpc away. To reach much lower X-ray luminosities that are more typical of XRBs in the Milky Way (Lx <~ 10^37 erg/s), we have observed M31 in 4 NuSTAR fields for more than 1 Ms total exposure, covering younger stellar population in a swath of the disk (within the footprint of the Panchromatic Hubble Andromeda Treasury (PHAT) Survey) and the older populations of the bulge. We detect 120 sources in the 4-25 keV band and over 40 hard band (12-25 keV) accreting black holes and neutron stars, distinguished by their spectral shape in this band. The luminosity function (LF) of the hard band detected sources are compared to Swift/BAT-derived LFs of the Milky Way population, which reveals an excess of luminous sources in M31 when correcting for star formation rate and stellar mass. We also discuss implications for this updated understanding of XRB populations on early-Universe measurements in, e.g., the 7 Ms Chandra Deep Field survey.

  10. The VIMOS VLT Deep Survey: Star Formation Since z≃q5 and Mass Assembly from the VVDS-SWIRE Sample

    NASA Astrophysics Data System (ADS)

    Le Fèvre, O.; Arnouts, S.; Tresse, L.; Ilbert, O.; Lonsdale, C.; Polletta, M.; Rowan-Robinson, M.; Zamorani, G.; Zucca, E.; Bardelli, S.; Paltani, S.; Pozzetti, L.; Bottini, D.; Garilli, B.; Le Brun, V.; Maccagni, D.; Picat, J. P.; Scaramella, R.; Scodeggio, M.; Shupe, D.; Surace, J.; Vettolani, G.; Zanichelli, A.; Adami, C.; Bolzonella, M.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Cucciati, O.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Iovino, A.; McCracken, H. J.; Marano, B.; Marinoni, C.; Mazure, A.; Meneux, B.; Merighi, R.; Pellò, R.; Pollo, A.; Radovich, M.; Bondi, M.; Bongiorno, A.; Brinchmann, J.; de La Torre, S.; Lamareille, F.; Mellier, Y.; Merluzzi, P.; Temporin, S.; Vergani, D.; Walcher, C. J.

    2007-12-01

    The VIMOS VLT Deep Survey is enabling to trace from one single survey the star formation history in the Universe over 12 billion years of evolution. We find that the star formation rate is strongly linked to the different types of galaxies. While the Luminosity Density of irregular-like galaxies decreased by more than a factor 3.5 from z=1.2 to z=0.2, the LD for early-type galaxies increased by a factor 1.7. Star formation happened in several phases, strongly luminosity dependent, with star formation gradually shifting from the first massive galaxies to less massive systems. The peak in SFR at z=3.5 is identified with the end of the mass assembly of the most luminous galaxies (MAB(1500Å)<-21). We use the SWIRE Spitzer-IRAC observations of the VVDS-02h field to assemble a flux-limited sample at 3.8μm of 1500 galaxies with spectroscopic redshifts and more than 22000 galaxies with photometric redshifts up to z=2 and build the rest-frame K-band luminosity function and stellar mass density. We find that the global stellar mass density has remained relatively constant since z˜1, but the epoch 1

  11. He II emitters in the VIMOS VLT Deep Survey: Population III star formation or peculiar stellar populations in galaxies at 2 < z < 4.6?

    NASA Astrophysics Data System (ADS)

    Cassata, P.; Le Fèvre, O.; Charlot, S.; Contini, T.; Cucciati, O.; Garilli, B.; Zamorani, G.; Adami, C.; Bardelli, S.; Le Brun, V.; Lemaux, B.; Maccagni, D.; Pollo, A.; Pozzetti, L.; Tresse, L.; Vergani, D.; Zanichelli, A.; Zucca, E.

    2013-08-01

    Aims: The aim of this work is to identify He II emitters at 2 < z < 4.6 and to constrain the source of the hard ionizing continuum that powers the He II emission. Methods: We assembled a sample of 277 galaxies with a highly reliable spectroscopic redshift at 2 < z < 4.6 from the VIMOS-VLT Deep Survey (VVDS) Deep and Ultra-Deep data, and we identified 39 He II λ1640 emitters. We studied their spectral properties, measuring the fluxes, equivalent widths (EW), and full width at half maximum (FWHM) for most relevant lines, including He II λ1640, Lyα line, Si II λ1527, and C IV λ1549. Results: About 10% of galaxies at z ~ 3 and iAB ≤ 24.75 show He II in emission, with rest frame equivalent widths EW0 ~ 1-7 Å, equally distributed between galaxies with Lyα in emission or in absorption. We find 11 (3.9% of the global population) reliable He II emitters with unresolved He II lines (FWHM0 < 1200 km s-1), 13 (4.6% of the global population) reliable emitters with broad He II emission (FWHM0 > 1200 km s-1), 3 active galactic nuclei (AGN), and an additional 12 possible He II emitters. The properties of the individual broad emitters are in agreement with expectations from a Wolf-Rayet (W-R) model. Instead, the properties of the narrow emitters are not compatible with this model, nor with predictions of gravitational cooling radiation produced by gas accretion, unless this is severely underestimated by current models by more than two orders of magnitude. Rather, we find that the EW of the narrow He II line emitters are in agreement with expectations for a Population III (PopIII) star formation, if the episode of star formation is continuous, and we calculate that a PopIII star formation rate (SFR) of 0.1-10 M⊙ yr-1 alone is enough to sustain the observed He II flux. Conclusions: We conclude that narrow He II emitters are powered either by the ionizing flux from a stellar population rare at z ~ 0 but much more common at z ~ 3, or by PopIII star formation. As proposed by

  12. The Deep2 Galaxy Redshift Survey: Mean Ages and Metallicities ofRed Field Galaxies at Z ~; 0.9 from Stacked Keck/Deimos Spectra

    SciTech Connect

    Schiavon, Ricardo P.; Faber, S.M.; Konidaris, Nicholas; Graves,Genevieve; Willmer, Christopher N.A.; Weiner, Benjamin J.; Coil, AlisonL.; Cooper, Michael C.; Davis, Marc; Harker, Justin; Koo, David C.; Newman, Jeffrey A.; Yan, Renbin

    2006-10-19

    As part of the DEEP2 galaxy redshift survey, we analyze absorption line strengths in stacked Keck/DEIMOS spectra of red field galaxies with weak to no emission lines, at redshifts 0.7 {approx}< z {approx}< 1. Comparison with models of stellar population synthesis shows that red galaxies at z {approx} 0:9 have mean luminosity-weighted ages of the order of only 1 Gyr and at least solar metallicities. These ages cannot be reconciled with a scenario where all stars evolved passively after forming at very high z. Rather, a significant fraction of stars can be no more than 1 Gyr old, which means that some star formation in the stacked populations continued to at least z {approx} 1:2. Furthermore, a comparison of these distant galaxies with a local SDSS sample, using stellar populations synthesis models, shows that the drop in the equivalent width of H{delta} from z {approx} 0:9 to 0.1 is less than predicted by passively evolving models. This admits of two interpretations: either each individual galaxy experiences continuing low-level star formation, or the red-sequence galaxy population from z {approx} 0:9 to 0.1 is continually being added to by new galaxies with younger stars.

  13. The role of the Bay of Biscay Mesozoic extensional structure in the configuration of the Pyrenean orogen: Constraints from the MARCONI deep seismic reflection survey

    NASA Astrophysics Data System (ADS)

    Roca, Eduard; MuñOz, Josep Anton; Ferrer, Oriol; Ellouz, Nadine

    2011-04-01

    Seismic interpretation of the MARCONI deep seismic survey enables recognition of the upper crustal structure of the eastern part of the Bay of Biscay and the main features of its Alpine geodynamic evolution. The new data denotes that two domains with different Pyrenean and north foreland structures exist in the Bay of Biscay. In the eastern or Basque-Parentis Domain, the North Pyrenean front is located close to the Spanish coast, and the northern foreland of the Pyrenees is constituted by a continental crust thinned by a north dipping fault that induced the formation of the Early Cretaceous Parentis Basin. In the western or Cantabrian Domain, the North Pyrenean front is shifted to the north and deforms a narrower and deeper foreland basin which lies on the top of a transitional crust formed from the exhumation of lithospheric mantle along a south dipping extensional low-angle fault during the Early Cretaceous. The transition between these two domains corresponds to a soft transfer zone linking the shifted North Pyrenean fronts and a north- to WNW-directed thrust that places the continental crust of the Landes Plateau over the transitional crust of the Bay of Biscay abyssal plain. Comparison between this structure and regional data enables characterization of the extensional rift system developed between Iberia and Eurasia during the Late Jurassic and Cretaceous and recognizes that this rift system controlled not only the location and features of the Pyrenean thrust sheets but also the overall structure of this orogen.

  14. A Deep Near-Infrared Survey of the N 49 Region around the Soft Gamma-Ray Repeater 0526-66

    NASA Technical Reports Server (NTRS)

    Klose, S.; Henden, A. A.; Geppert, U.; Greiner, J.; Guetter, H. H.; Hartmann, D. H.; Kouveliotou, C.; Luginbuhl, C. B.; Stecklurn, B.; Vrba, F. J.

    2004-01-01

    We report the results of a deep near-infrared survey of the vicinity of supernova remnant N49 in the Large Magellanic Cloud (LMC), which contains the soft gamma-ray repeater (SGR) 0526-66. Two of the four confirmed SGRs are potentially associated with compact stellar clusters. We thus searched for a similar association of SGR0526-66, and find the unexplored young stellar cluster SL 463 at a projected distance of approx. 30 pc from the SGR. This constitutes the third cluster-SGR link, and lends support to scenarios in which SGR progenitors originate in young, embedded clusters. If real, the cluster-SGR association constrains the age and thus the initial mass of these stars. In addition, our high-resolution images of the super- nova remnant N49 reveal an area of excess K-band flux in the southeastern part of the SNR. This feature coincides with the maximum flux area at 8.28 microns as detected by the Midcourse Space Experiment (MSX satellite), which we identify with IRAS 052594607.

  15. ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: CO Luminosity Functions and the Evolution of the Cosmic Density of Molecular Gas

    NASA Astrophysics Data System (ADS)

    Decarli, Roberto; Walter, Fabian; Aravena, Manuel; Carilli, Chris; Bouwens, Rychard; da Cunha, Elisabete; Daddi, Emanuele; Ivison, R. J.; Popping, Gergö; Riechers, Dominik; Smail, Ian R.; Swinbank, Mark; Weiss, Axel; Anguita, Timo; Assef, Roberto J.; Bauer, Franz E.; Bell, Eric F.; Bertoldi, Frank; Chapman, Scott; Colina, Luis; Cortes, Paulo C.; Cox, Pierre; Dickinson, Mark; Elbaz, David; Gónzalez-López, Jorge; Ibar, Edo; Infante, Leopoldo; Hodge, Jacqueline; Karim, Alex; Le Fevre, Olivier; Magnelli, Benjamin; Neri, Roberto; Oesch, Pascal; Ota, Kazuaki; Rix, Hans-Walter; Sargent, Mark; Sheth, Kartik; van der Wel, Arjen; van der Werf, Paul; Wagg, Jeff

    2016-12-01

    In this paper we use ASPECS, the ALMA Spectroscopic Survey in the Hubble Ultra Deep Field in band 3 and band 6, to place blind constraints on the CO luminosity function and the evolution of the cosmic molecular gas density as a function of redshift up to z ˜ 4.5. This study is based on galaxies that have been selected solely through their CO emission and not through any other property. In all of the redshift bins the ASPECS measurements reach the predicted “knee” of the CO luminosity function (around 5 × 109 K km s-1 pc2). We find clear evidence of an evolution in the CO luminosity function with respect to z ˜ 0, with more CO-luminous galaxies present at z ˜ 2. The observed galaxies at z ˜ 2 also appear more gas-rich than predicted by recent semi-analytical models. The comoving cosmic molecular gas density within galaxies as a function of redshift shows a drop by a factor of 3-10 from z ˜ 2 to z ˜ 0 (with significant error bars), and possibly a decline at z > 3. This trend is similar to the observed evolution of the cosmic star formation rate density. The latter therefore appears to be at least partly driven by the increased availability of molecular gas reservoirs at the peak of cosmic star formation (z ˜ 2).

  16. Twenty-Three High-Redshift Supernovae from the Institute for Astronomy Deep Survey: Doubling the Supernova Sample at z > 0.7

    NASA Astrophysics Data System (ADS)

    Barris, Brian J.; Tonry, John L.; Blondin, Stéphane; Challis, Peter; Chornock, Ryan; Clocchiatti, Alejandro; Filippenko, Alexei V.; Garnavich, Peter; Holland, Stephen T.; Jha, Saurabh; Kirshner, Robert P.; Krisciunas, Kevin; Leibundgut, Bruno; Li, Weidong; Matheson, Thomas; Miknaitis, Gajus; Riess, Adam G.; Schmidt, Brian P.; Smith, R. Chris; Sollerman, Jesper; Spyromilio, Jason; Stubbs, Christopher W.; Suntzeff, Nicholas B.; Aussel, Hervé; Chambers, K. C.; Connelley, M. S.; Donovan, D.; Henry, J. Patrick; Kaiser, Nick; Liu, Michael C.; Martín, Eduardo L.; Wainscoat, Richard J.

    2004-02-01

    We present photometric and spectroscopic observations of 23 high-redshift supernovae (SNe) spanning a range of z=0.34-1.03, nine of which are unambiguously classified as Type Ia. These SNe were discovered during the IfA Deep Survey, which began in 2001 September and observed a total of 2.5 deg2 to a depth of approximately m~25-26 in RIZ over 9-17 visits, typically every 1-3 weeks for nearly 5 months, with additional observations continuing until 2002 April. We give a brief description of the survey motivations, observational strategy, and reduction process. This sample of 23 high-redshift SNe includes 15 at z>=0.7, doubling the published number of objects at these redshifts, and indicates that the evidence for acceleration of the universe is not due to a systematic effect proportional to redshift. In combination with the recent compilation of Tonry et al. (2003), we calculate cosmological parameter density contours that are consistent with the flat universe indicated by the cosmic microwave background (Spergel et al. 2003). Adopting the constraint that Ωtotal=1.0, we obtain best-fit values of (Ωm,ΩΛ)=(0.33,0.67) using 22 SNe from this survey augmented by the literature compilation. We show that using the empty-beam model for gravitational lensing does not eliminate the need for ΩΛ>0. Experience from this survey indicates great potential for similar large-scale surveys while also revealing the limitations of performing surveys for z>1 SNe from the ground. CFHT: Based in part on observations obtained at the Canada-France-Hawaii Telescope (CFHT), which is operated by the National Research Council of Canada, the Institut National des Science de l'Univers of the Centre National de la Recherche Scientifique of France, and the University of Hawaii. CTIO: Based in part on observations taken at the Cerro Tololo Inter-American Observatory. Keck: Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership

  17. The VIMOS Ultra Deep Survey: Lyα emission and stellar populations of star-forming galaxies at 2 < z < 2.5

    NASA Astrophysics Data System (ADS)

    Hathi, N. P.; Le Fèvre, O.; Ilbert, O.; Cassata, P.; Tasca, L. A. M.; Lemaux, B. C.; Garilli, B.; Le Brun, V.; Maccagni, D.; Pentericci, L.; Thomas, R.; Vanzella, E.; Zamorani, G.; Zucca, E.; Amorín, R.; Bardelli, S.; Cassarà, L. P.; Castellano, M.; Cimatti, A.; Cucciati, O.; Durkalec, A.; Fontana, A.; Giavalisco, M.; Grazian, A.; Guaita, L.; Koekemoer, A.; Paltani, S.; Pforr, J.; Ribeiro, B.; Schaerer, D.; Scodeggio, M.; Sommariva, V.; Talia, M.; Tresse, L.; Vergani, D.; Capak, P.; Charlot, S.; Contini, T.; Cuby, J. G.; de la Torre, S.; Dunlop, J.; Fotopoulou, S.; López-Sanjuan, C.; Mellier, Y.; Salvato, M.; Scoville, N.; Taniguchi, Y.; Wang, P. W.

    2016-04-01

    The aim of this paper is to investigate spectral and photometric properties of 854 faint (iAB ≲ 25 mag) star-forming galaxies (SFGs) at 2 < z < 2.5 using the VIMOS Ultra-Deep Survey (VUDS) spectroscopic data and deep multi-wavelength photometric data in three extensively studied extragalactic fields (ECDFS, VVDS, COSMOS). These SFGs were targeted for spectroscopy as a result of their photometric redshifts. The VUDS spectra are used to measure the UV spectral slopes (β) as well as Lyα equivalent widths (EW). On average, the spectroscopically measured β (-1.36 ± 0.02), is comparable to the photometrically measured β (-1.32 ± 0.02), and has smaller measurement uncertainties. The positive correlation of β with the spectral energy distribution (SED)-based measurement of dust extinction Es(B-V) emphasizes the importance of β as an alternative dust indicator at high redshifts. To make a proper comparison, we divide these SFGs into three subgroups based on their rest-frame Lyα EW: SFGs with no Lyα emission (SFGN; EW ≤ 0 Å), SFGs with Lyα emission (SFGL; EW > 0 Å), and Lyα emitters (LAEs; EW ≥ 20 Å). The fraction of LAEs at these redshifts is ~10%, which is consistent with previous observations. We compared best-fitSED-estimated stellar parameters of the SFGN, SFGL and LAE samples. For the luminosities probed here (~ L∗), we find that galaxies with and without Lyα in emission have small but significant differences in their SED-based properties. We find that LAEs have less dust, and lower star-formation rates (SFR) compared to non-LAEs. We also find that LAEs are less massive compared to non-LAEs, though the difference is smaller and less significant compared to the SFR and Es(B-V). When we divide the LAEs according to their Spitzer/IRAC 3.6 μm fluxes, we find that the fraction of IRAC-detected (m3.6 ≲ 25 mag) LAEs is much higher than the fraction of IRAC-detected narrow band (NB)-selected LAEs at z ≃ 2-3. This could imply that UV-selected LAEs

  18. Lake Nam Co (Tibet, China) - a suitable target for a deep drilling project as confirmed by a preliminary airgun seismic survey

    NASA Astrophysics Data System (ADS)

    Spiess, V.; Daut, G.; Wenau, S.; Gernhardt, F.; Wang, J.; Schwenk, T.; Haberzettl, T.; Zhu, L.; Maeusbacher, R.

    2014-12-01

    Lake Nam Co, located on the central Tibetan Plateau at the intersection of the Westerlies and the Indian Ocean Summer Monsoon, is well suited to study the monsoonal regime over different time scales. High-resolution and continuous sedimentary records from the Tibetan Plateau are still rare and only few reach back to the Last Glacial Maximum. For Nam Co, numerous multiproxy studies unravel the regional paleoclimate and paleoenvironmental history for the past 24,000 years. These promising results demonstrate the potential of Lake Nam Co as a geoarchive, but nature, thickness and geologic time of the sediment fill have not yet been determined. Therefore the Institute of Tibetan Plateau Research (Chinese Academy of Sciences) and the Universities of Bremen and Jena jointly carried out an airgun multichannel seismic survey at Nam Co in June/July 2014. As main equipment, a micro GI Gun(2 x 0.1 L) was used in conjunction with a 64 m long seismic streamer (32 channels/2 m spacing) to achieve deep signal penetration, to confirm a thick sediment infill and to prove the suitability for deep coring of several hundred meters. Although only few lines could be shot due to technical and weather issues, several lines particularly from the deepest part of the lake provide new insight. Preliminary data processing and interpretation reveal a well layered sediment cover of >700 m in the center of the lake. Seismic facies appears to vary in a cyclic manner, indicating a coupling to climatically-driven changes in lake level and sediment delivery. From a comparison with the Holocene/Late Glacial sedimentary and seismic record, several similar units could be imaged. Furthermore, rapid sedimentation is confirmed from the continuous cover of growth faults and doming, and continuous sedimentation throughout glacial/interglacial cycles appears likely due to the absence of erosional unconformities. By tentatively assigning these units to marine isotope stages, different seismostratigraphies can

  19. A NEW INFRARED COLOR CRITERION FOR THE SELECTION OF 0 < z < 7 AGNs: APPLICATION TO DEEP FIELDS AND IMPLICATIONS FOR JWST SURVEYS

    SciTech Connect

    Messias, H.; Afonso, J.; Salvato, M.; Mobasher, B.; Hopkins, A. M.

    2012-08-01

    It is widely accepted that observations at mid-infrared (mid-IR) wavelengths enable the selection of galaxies with nuclear activity, which may not be revealed even in the deepest X-ray surveys. Many mid-IR color-color criteria have been explored to accomplish this goal and tested thoroughly in the literature. Besides missing many low-luminosity active galactic nuclei (AGNs), one of the main conclusions is that, with increasing redshift, the contamination by non-active galaxies becomes significant (especially at z {approx}> 2.5). This is problematic for the study of the AGN phenomenon in the early universe, the main goal of many of the current and future deep extragalactic surveys. In this work new near- and mid-IR color diagnostics are explored, aiming for improved efficiency-better completeness and less contamination-in selecting AGNs out to very high redshifts. We restrict our study to the James Webb Space Telescope wavelength range (0.6-27 {mu}m). The criteria are created based on the predictions by state-of-the-art galaxy and AGN templates covering a wide variety of galaxy properties, and tested against control samples with deep multi-wavelength coverage (ranging from the X-rays to radio frequencies). We show that the colors K{sub s} - [4.5], [4.5] - [8.0], and [8.0] - [24] are ideal as AGN/non-AGN diagnostics at, respectively, z {approx}< 1, 1 {approx}< z {approx}< 2.5, and z {approx}> 2.5-3. However, when the source redshift is unknown, these colors should be combined. We thus develop an improved IR criterion (using K{sub s} and IRAC bands, KI) as a new alternative at z {approx}< 2.5. KI does not show improved completeness (50%-60% overall) in comparison to commonly used Infrared Array Camera (IRAC) based AGN criteria, but is less affected by non-AGN contamination (revealing a >50%-90% level of successful AGN selection). We also propose KIM (using K{sub s} , IRAC, and MIPS 24 {mu}m bands, KIM), which aims to select AGN hosts from local distances to as far

  20. X-Ray Spectral Analyses of AGNs from the 7Ms Chandra Deep Field-South Survey: The Distribution, Variability, and Evolutions of AGN Obscuration

    NASA Astrophysics Data System (ADS)

    Liu, Teng; Tozzi, Paolo; Wang, Jun-Xian; Brandt, William N.; Vignali, Cristian; Xue, Yongquan; Schneider, Donald P.; Comastri, Andrea; Yang, Guang; Bauer, Franz E.; Paolillo, Maurizio; Luo, Bin; Gilli, Roberto; Wang, Q. Daniel; Giavalisco, Mauro; Ji, Zhiyuan; Alexander, David M.; Mainieri, Vincenzo; Shemmer, Ohad; Koekemoer, Anton; Risaliti, Guido

    2017-09-01

    We present a detailed spectral analysis of the brightest active galactic nuclei (AGNs) identified in the 7Ms Chandra Deep Field-South (CDF-S) survey over a time span of 16 years. Using a model of an intrinsically absorbed power-law plus reflection, with possible soft excess and narrow Fe Kα line, we perform a systematic X-ray spectral analysis, both on the total 7Ms exposure and in four different periods with lengths of 2–21 months. With this approach, we not only present the power-law slopes, column densities {N}{{H}}, observed fluxes, and absorption-corrected 2–10 keV luminosities L X for our sample of AGNs, but also identify significant spectral variabilities among them on timescales of years. We find that the {N}{{H}} variabilities can be ascribed to two different types of mechanisms, either flux-driven or flux-independent. We also find that the correlation between the narrow Fe line EW and {N}{{H}} can be well explained by the continuum suppression with increasing {N}{{H}}. Accounting for the sample incompleteness and bias, we measure the intrinsic distribution of {N}{{H}} for the CDF-S AGN population and present reselected subsamples that are complete with respect to {N}{{H}}. The {N}{{H}}-complete subsamples enable us to decouple the dependences of {N}{{H}} on L X and on redshift. Combining our data with those from C-COSMOS, we confirm the anticorrelation between the average {N}{{H}} and L X of AGN, and find a significant increase of the AGN-obscured fraction with redshift at any luminosity. The obscured fraction can be described as {f}{obscured}≈ 0.42 {(1+z)}0.60.

  1. Microclimate controls on weathering: Insights into deep critical zone evolution from seismic refraction surveys in the Susquehanna Shale Hills Critical Zone Observatory

    NASA Astrophysics Data System (ADS)

    West, N.; Kirby, E.; Nyblade, A.; Brantley, S. L.; Clarke, B. A.

    2015-12-01

    The formation of regolith is fundamental to the functioning and structure of the critical zone - the physically and chemically altered material formed from in situ parent bedrock that is available for transport. Understanding how regolith production and transport respond to perturbations in climate and/or tectonic forcing remains a first-order question. At the Susquehanna Shale Hills Critical Zone Observatory (SSHO), high resolution LiDAR-derived topographic data and depths to hand auger refusal reveal a systematic asymmetry in hillslope gradient and mobile regolith thickness; both are greater on north-facing hillslopes. Hydrologic and geochemical studies at the SSHO also suggest asymmetric sediment transport, fluid flow, and mineral weathering with respect to hillslope aspect. Here, we combine shallow seismic surveys completed along 4 hillslope transects (2 north-facing and 2-south facing), 2 ridgetops transects, and subsurface observations in boreholes to investigate the role of climate in inducing fracturing and priming the development of the observed asymmetry. Comparisons of shallow p-wave velocities with borehole and pit observations lead us to hypothesize the presence of three distinct layers at SSHO: 1) a deep, high velocity layer that is consistent with unweathered shale bedrock; 2) an intermediate velocity layer that is consistent with fractured and chemically altered bedrock which overlies unaltered bedrock, and 3) a shallow, slow velocity layer that is consistent with mobile material or shallow soil. Shallow p-wave velocity profiles suggest differences in thickness for both the mobile and immobile regolith material with respect to aspect. Patterns of p-wave velocities with depth are consistent with patterns of fracture densities observed in boreholes and with predictive cracking intensity models related to frost action. The models and data are consistent with climate as a primary driver for the development of asymmetry in the subsurface architecture at

  2. THE STRUCTURE AND STELLAR CONTENT OF THE OUTER DISKS OF GALAXIES: A NEW VIEW FROM THE Pan-STARRS1 MEDIUM DEEP SURVEY

    SciTech Connect

    Zheng, Zheng; Thilker, David A.; Heckman, Timothy M.; Meurer, Gerhardt R.; Burgett, W. S.; Huber, M. E.; Kaiser, N.; Magnier, E. A.; Tonry, J. L.; Wainscoat, R. J.; Waters, C.; Chambers, K. C.; Metcalfe, N.; Price, P. A.

    2015-02-20

    We present the results of an analysis of Pan-STARRS1 Medium Deep Survey multi-band (grizy) images of a sample of 698 low-redshift disk galaxies that span broad ranges in stellar mass, star-formation rate, and bulge/disk ratio. We use population synthesis spectral energy distribution fitting techniques to explore the radial distribution of the light, color, surface mass density, mass/light ratio, and age of the stellar populations. We characterize the structure and stellar content of the galaxy disks out to radii of about twice Petrosian r {sub 90}, beyond which the halo light becomes significant. We measure normalized radial profiles for sub-samples of galaxies in three bins each of stellar mass and concentration. We also fit radial profiles to each galaxy. The majority of galaxies have down-bending radial surface brightness profiles in the bluer bands with a break radius at roughly r {sub 90}. However, they typically show single unbroken exponentials in the reddest bands and in the stellar surface mass density. We find that the mass/light ratio and stellar age radial profiles have a characteristic 'U' shape. There is a good correlation between the amplitude of the down-bend in the surface brightness profile and the rate of the increase in the M/L ratio in the outer disk. As we move from late- to early-type galaxies, the amplitude of the down-bend and the radial gradient in M/L both decrease. Our results imply a combination of stellar radial migration and suppression of recent star formation can account for the stellar populations of the outer disk.

  3. Deep Advanced Camera for Surveys Imaging in the Globular Cluster NGC 6397: the Cluster Color-Magnitude Diagram and Luminosity Function

    NASA Astrophysics Data System (ADS)

    Richer, Harvey B.; Dotter, Aaron; Hurley, Jarrod; Anderson, Jay; King, Ivan; Davis, Saul; Fahlman, Gregory G.; Hansen, Brad M. S.; Kalirai, Jason; Paust, Nathaniel; Rich, R. Michael; Shara, Michael M.

    2008-06-01

    We present the color-magnitude diagram (CMD) from deep Hubble Space Telescope imaging in the globular cluster NGC 6397. The Advanced Camera for Surveys (ACS) was used for 126 orbits to image a single field in two colors (F814W, F606W) 5' SE of the cluster center. The field observed overlaps that of archival WFPC2 data from 1994 and 1997 which were used to proper motion (PM) clean the data. Applying the PM corrections produces a remarkably clean CMD which reveals a number of features never seen before in a globular cluster CMD. In our field, the main-sequence stars appeared to terminate close to the location in the CMD of the hydrogen-burning limit predicted by two independent sets of stellar evolution models. The faintest observed main-sequence stars are about a magnitude fainter than the least luminous metal-poor field halo stars known, suggesting that the lowest-luminosity halo stars still await discovery. At the bright end the data extend beyond the main-sequence turnoff to well up the giant branch. A populous white dwarf cooling sequence is also seen in the cluster CMD. The most dramatic features of the cooling sequence are its turn to the blue at faint magnitudes as well as an apparent truncation near F814W = 28. The cluster luminosity and mass functions were derived, stretching from the turnoff down to the hydrogen-burning limit. It was well modeled with either a very flat power-law or a lognormal function. In order to interpret these fits more fully we compared them with similar functions in the cluster core and with a full N-body model of NGC 6397 finding satisfactory agreement between the model predictions and the data. This exercise demonstrates the important role and the effect that dynamics has played in altering the cluster initial mass function.

  4. A PUBLIC, K-SELECTED, OPTICAL-TO-NEAR-INFRARED CATALOG OF THE EXTENDED CHANDRA DEEP FIELD SOUTH (ECDFS) FROM THE MULTIWAVELENGTH SURVEY BY YALE-CHILE (MUSYC)

    SciTech Connect

    Taylor, Edward N.; Franx, Marijn; Quadri, Ryan F.; Damen, Maaike; Hildebrandt, Hendrik; Van Dokkum, Pieter G.; Herrera, David; Gawiser, Eric; Bell, Eric F.; Barrientos, L. Felipe; Blanc, Guillermo A.; Castander, Francisco J.; Gonzalez-Perez, Violeta; Hall, Patrick B.; Kriek, Mariska; Labbe, Ivo; Lira, Paulina; Maza, Jose; Rudnick, Gregory; Treister, Ezequiel

    2009-08-01

    We present a new, K-selected, optical-to-near infrared photometric catalog of the Extended Chandra Deep Field South (ECDFS), making it publicly available to the astronomical community.{sup 22}Imaging and spectroscopy data and catalogs are freely available through the MUSYC Public Data Release webpage: http://www.astro.yale.edu/MUSYC/. The data set is founded on publicly available imaging, supplemented by original z'JK imaging data collected as part of the MUltiwavelength Survey by Yale-Chile (MUSYC). The final photometric catalog consists of photometry derived from UU {sub 38} BVRIz'JK imaging covering the full 1/2 x 1/2 square circ of the ECDFS, plus H-band photometry for approximately 80% of the field. The 5{sigma} flux limit for point sources is K{sup (AB)}{sub tot}= 22.0. This is also the nominal completeness and reliability limit of the catalog: the empirical completeness for 21.75 < K < 22.00 is {approx}>85%. We have verified the quality of the catalog through both internal consistency checks, and comparisons to other existing and publicly available catalogs. As well as the photometric catalog, we also present catalogs of photometric redshifts and rest-frame photometry derived from the 10-band photometry. We have collected robust spectroscopic redshift determinations from published sources for 1966 galaxies in the catalog. Based on these sources, we have achieved a (1{sigma}) photometric redshift accuracy of {delta}z/(1 + z) = 0.036, with an outlier fraction of 7.8%. Most of these outliers are X-ray sources. Finally, we describe and release a utility for interpolating rest-frame photometry from observed spectral energy distributions, dubbed InterRest.{sup 23}InterRest is available via http://www.strw.leidenuniv.nl/{approx}ent/InterRest. Documentation and a complete walkthrough can be found at the same address.

  5. Evolution of clustering length, large-scale bias, and host halo mass at 2 < z < 5 in the VIMOS Ultra Deep Survey (VUDS)⋆

    NASA Astrophysics Data System (ADS)

    Durkalec, A.; Le Fèvre, O.; Pollo, A.; de la Torre, S.; Cassata, P.; Garilli, B.; Le Brun, V.; Lemaux, B. C.; Maccagni, D.; Pentericci, L.; Tasca, L. A. M.; Thomas, R.; Vanzella, E.; Zamorani, G.; Zucca, E.; Amorín, R.; Bardelli, S.; Cassarà, L. P.; Castellano, M.; Cimatti, A.; Cucciati, O.; Fontana, A.; Giavalisco, M.; Grazian, A.; Hathi, N. P.; Ilbert, O.; Paltani, S.; Ribeiro, B.; Schaerer, D.; Scodeggio, M.; Sommariva, V.; Talia, M.; Tresse, L.; Vergani, D.; Capak, P.; Charlot, S.; Contini, T.; Cuby, J. G.; Dunlop, J.; Fotopoulou, S.; Koekemoer, A.; López-Sanjuan, C.; Mellier, Y.; Pforr, J.; Salvato, M.; Scoville, N.; Taniguchi, Y.; Wang, P. W.

    2015-11-01

    We investigate the evolution of galaxy clustering for galaxies in the redshift range 2.0 Deep Survey (VUDS). We present the projected (real-space) two-point correlation function wp(rp) measured by using 3022 galaxies with robust spectroscopic redshifts in two independent fields (COSMOS and VVDS-02h) covering in total 0.8deg2. We quantify how the scale dependent clustering amplitude r0 changes with redshift making use of mock samples to evaluate and correct the survey selection function. Using a power-law model ξ(r) = (r/r0)- γ we find that the correlation function for the general population is best fit by a model with a clustering length r0 = 3.95+0.48-0.54 h-1 Mpc and slope γ = 1.8+0.02-0.06 at z ~ 2.5, r0 = 4.35 ± 0.60 h-1 Mpc and γ = 1.6+0.12-0.13 at z ~ 3.5. We use these clustering parameters to derive the large-scale linear galaxy bias bLPL, between galaxies and dark matter. We find bLPL = 2.68 ± 0.22 at redshift z ~ 3 (assuming σ8 = 0.8), significantly higher than found at intermediate and low redshifts for the similarly general galaxy populations. We fit a halo occupation distribution (HOD) model to the data and we obtain that the average halo mass at redshift z ~ 3 is Mh = 1011.75 ± 0.23 h-1M⊙. From this fit we confirm that the large-scale linear galaxy bias is relatively high at bLHOD = 2.82 ± 0.27. Comparing these measurements with similar measurements at lower redshifts we infer that the star-forming population of galaxies at z ~ 3 should evolve into the massive and bright (Mr< -21.5)galaxy population, which typically occupy haloes of mass ⟨ Mh ⟩ = 1013.9 h-1M⊙ at redshift z = 0. Based on data obtained with the European Southern Observatory Very Large Telescope, Paranal, Chile, under Large Program 185.A-0791.Appendices are available in electronic form at http://www.aanda.org

  6. The VIMOS VLT Deep Survey. Evolution of the luminosity functions by galaxy type up to z = 1.5 from first epoch data

    NASA Astrophysics Data System (ADS)

    Zucca, E.; Ilbert, O.; Bardelli, S.; Tresse, L.; Zamorani, G.; Arnouts, S.; Pozzetti, L.; Bolzonella, M.; McCracken, H. J.; Bottini, D.; Garilli, B.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Picat, J. P.; Scaramella, R.; Scodeggio, M.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnaboldi, M.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Iovino, A.; Marano, B.; Marinoni, C.; Mazure, A.; Meneux, B.; Merighi, R.; Paltani, S.; Pellò, R.; Pollo, A.; Radovich, M.; Bondi, M.; Bongiorno, A.; Busarello, G.; Cucciati, O.; Gregorini, L.; Lamareille, F.; Mathez, G.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2006-09-01

    From first epoch observations of the VIMOS VLT Deep Survey (VVDS) we have derived luminosity functions for galaxy samples selected by spectral type out to z=1.5. With the VVDS we are able to investigate within the same sample the evolution of the type dependent luminosity function selected in several rest-frame bands over 70% of the age of the Universe. The simple I_AB=24 VVDS magnitude limit is significantly fainter than other complete spectroscopic surveys and allows the determination of the faint end slope of the luminosity function with unprecedented accuracy. Galaxies have been classified in four spectral types, from early type to irregular galaxies, using their colours and redshift. Luminosity functions have been computed in the U, B, V, R and I rest frame bands for each type, in redshift bins from z=0.05 to z=1.5. In all the considered rest frame bands, we find a significant steepening of the luminosity function from early to late types. The characteristic luminosity M* of the Schechter function is significantly fainter for late type galaxies and this difference between types increases in the redder bands. For each spectral type we find a brightening of M* with increasing redshift, ranging from ≲0.5 mag for early type galaxies to ~1 mag for the latest type galaxies, while the slope of the luminosity function of each spectral type is consistent with being redshift-independent. The luminosity function of early type galaxies is consistent with passive evolution up to z˜ 1.1, whilst the number of bright (MB_AB< -20) early type galaxies has decreased by ~40% from z˜ 0.3 to z ˜ 1.1. The normalisation of the luminosity function of latest type galaxies evolves strongly with redshift with an increase of more than a factor 2 from z˜ 0.3 to z˜ 1.3: the density of bright (MB_AB< -20) late type galaxies in the same redshift range increases of a factor ~6.6. These results indicate a strong type-dependent evolution and identifies the latest spectral types as

  7. The VIMOS VLT Deep Survey final data release: a spectroscopic sample of 35 016 galaxies and AGN out to z ~ 6.7 selected with 17.5 ≤ iAB ≤ 24.75

    NASA Astrophysics Data System (ADS)

    Le Fèvre, O.; Cassata, P.; Cucciati, O.; Garilli, B.; Ilbert, O.; Le Brun, V.; Maccagni, D.; Moreau, C.; Scodeggio, M.; Tresse, L.; Zamorani, G.; Adami, C.; Arnouts, S.; Bardelli, S.; Bolzonella, M.; Bondi, M.; Bongiorno, A.; Bottini, D.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; de la Torre, S.; Foucaud, S.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Iovino, A.; Lemaux, B.; López-Sanjuan, C.; McCracken, H. J.; Marano, B.; Marinoni, C.; Mazure, A.; Mellier, Y.; Merighi, R.; Merluzzi, P.; Paltani, S.; Pellò, R.; Pollo, A.; Pozzetti, L.; Scaramella, R.; Tasca, L.; Vergani, D.; Vettolani, G.; Zanichelli, A.; Zucca, E.

    2013-11-01

    Context. Deep representative surveys of galaxies at different epochs are needed to make progress in understanding galaxy evolution. Aims: We describe the completed VIMOS VLT Deep Survey and the final data release of 35 016 galaxies and type-I AGN with measured spectroscopic redshifts covering all epochs up to redshift z ~ 6.7, in areas from 0.142 to 8.7 square degrees, and volumes from 0.5 × 106 to 2 × 107 h-3 Mpc3. Methods: We selected samples of galaxies based solely on their i-band magnitude reaching iAB = 24.75. Spectra were obtained with VIMOS on the ESO-VLT integrating 0.75 h, 4.5 h, and 18 h for the Wide, Deep, and Ultra-Deep nested surveys, respectively. We demonstrate that any "redshift desert" can be crossed successfully using spectra covering 3650 ≤ λ ≤ 9350 Å. A total of 1263 galaxies were again observed independently within the VVDS and from the VIPERS and MASSIV surveys. They were used to establish the redshift measurements reliability, to assess completeness in the VVDS sample, and to provide a weighting scheme taking the survey selection function into account. We describe the main properties of the VVDS samples, and the VVDS is compared to other spectroscopic surveys in the literature. Results: In total we have obtained spectroscopic redshifts for 34 594 galaxies, 422 type-I AGN, and 12 430 Galactic stars. The survey enabled identifying galaxies up to very high redshifts with 4669 redshifts in 1 ≤ zspec ≤ 2, 561 in 2 ≤ zspec ≤ 3, and 468 with zspec > 3, and specific populations like Lyman-α emitters were identified out to z = 6.62. We show that the VVDS occupies a unique place in the parameter space defined by area, depth, redshift coverage, and number of spectra. Conclusions: The VIMOS VLT Deep Survey provides a comprehensive survey of the distant universe, covering all epochs since z ~ 6, or more than 12 Gyr of cosmic time, with a uniform selection, which is the largest such sample to date. A wealth of science results derived from

  8. THE EXTENDED CHANDRA DEEP FIELD-SOUTH SURVEY: OPTICAL SPECTROSCOPY OF FAINT X-RAY SOURCES WITH THE VLT AND KECK

    SciTech Connect

    Silverman, J. D.; Mainieri, V.; Rosati, P.; Salvato, M.; Hasinger, G.; Bergeron, J.; Capak, P.; Szokoly, G.; Gilli, R.; Tozzi, P.; Vignali, C.; Alexander, D. M.; Brandt, W. N.; Luo, B.; Rafferty, D.; Xue, Y. Q.; Lehmer, B. D.; Bauer, F. E.

    2010-11-15

    We present the results of a program to acquire high-quality optical spectra of X-ray sources detected in the Extended-Chandra Deep Field-South (E-CDF-S) and its central 2 Ms area. New spectroscopic redshifts, up to z = 4, are measured for 283 counterparts to Chandra sources with deep exposures (t {approx} 2-9 hr per pointing) using multi-slit facilities on both VLT (VIMOS) and Keck (DEIMOS), thus bringing the total number of spectroscopically identified X-ray sources to over 500 in this survey field. Since our new spectroscopic identifications are mainly associated with X-ray sources in the shallower 250 ks coverage, we provide a comprehensive catalog of X-ray sources detected in the E-CDF-S including the optical and near-infrared counterparts, determined by a likelihood routine, and redshifts (both spectroscopic and photometric), that incorporate published spectroscopic catalogs, thus resulting in a final sample with a high fraction (80%) of X-ray sources having secure identifications. We demonstrate the remarkable coverage of the luminosity-redshift plane now accessible from our data while emphasizing the detection of active galactic nuclei (AGNs) that contribute to the faint end of the luminosity function (L {sub 0.5-8keV} {approx} 10{sup 43}-10{sup 44} erg s{sup -1}) at 1.5 {approx}< z {approx}< 3 including those with and without broad emission lines. Our redshift catalog includes 17 type-2 QSOs at 1 {approx}< z {approx}< 3.5 that significantly increases such samples (2x). Based on our deepest (9 hr) VLT/VIMOS observation, we identify 'elusive' optically faint galaxies (R {sub mag} {approx} 25) at z {approx} 2-3 based upon the detection of interstellar absorption lines (e.g., O II+Si IV, C II], C IV); we highlight one such case, an absorption-line galaxy at z = 3.208 having no obvious signs of an AGN in its optical spectrum. In addition, we determine accurate distances to eight galaxy groups with extended X-ray emission detected both by Chandra and XMM

  9. Structure and photometry of an I less than 20.5 galaxy sample from the Hubble Space Telescope medium deep survey

    NASA Astrophysics Data System (ADS)

    Phillips, Andrew C.; Bershady, Matthew A.; Forbes, Duncan A.; Koo, David C.; Illingworth, Garth D.; Reitzel, David B.; Griffiths, Richard E.; Windhorst, Rogier A.

    1995-05-01

    A set of 100 faint galaxies from nine Hubble Space Telescope (HST) Wide Field Camera (WFC) I-band images have been analyzed as part of the Medium Deep Survey (MDS) Key Project. This sample reaches a depth of I approximately less than or equal to 20.5 (corresponding to B approximately 22-23) and complements the first set of fainter galaxies analyzed by the MDS team. Images were deconvolved using the Lucy-Richardson algorithm and a newly developed procedure designed to yield a more reliable determination of structure in the low-S/N regime. These deconvolved images were used to characterize the structure of the galaxies through quantative measurements of total magnitudes, half-light radii, exponential disk scale lengths, and disk-to-total rations. Extensive testing was done to establish the validity of the procedures used and to characterize the degree of systematic errors present in the analysis techniques. The observed size-magnitude distribution appears consistent with a scenario in which luminous galaxies have evolved little in intrinsic luminosity, size, or structure over recent epochs in a 'normal' cosmology (0 less than q0 less than 0.5 and Lambda0 = 0). The predicted nonevolving distributions were based on models designed to fit existing counts, colors, and redshifts of faint galaxies and on the observed correlations between metric rest-frame size and luminosity found in a nearby galaxy sample studied by Kent (1984-1985). The typical galaxy in our sample is expected to be at z approximately equal to 0.3, and to have a luminosity approximately 0.5 mag fainter than L* and a half-light radius of approximately 1 sec or approximately 6 kpc (H 0 = 50 km/s Mpc). The observed distribution of disk-to-total ratios, while uncertain, is in agreement with that of Kent's sample and thus supports the view that substantial evolution has not occurred over the look-back times characteristic of our sample.

  10. WHERE DO WET, DRY, AND MIXED GALAXY MERGERS OCCUR? A STUDY OF THE ENVIRONMENTS OF CLOSE GALAXY PAIRS IN THE DEEP2 GALAXY REDSHIFT SURVEY

    SciTech Connect

    Lin, Lihwai; Cooper, Michael C.; Willmer, Christopher N. A.; Jian, Hung-Yu; Chiueh, Tzihong; Koo, David C.; Guhathakurta, Puragra; Yan, Renbin; Coil, Alison L.; Croton, Darren J.; Gerke, Brian F.; Newman, Jeffrey A.

    2010-08-01

    We study the environments of wet, dry, and mixed galaxy mergers at 0.75 < z < 1.2 using close pairs in the DEEP2 Galaxy Redshift Survey. We find that the typical environment of dry and mixed merger candidates is denser than that of wet mergers, mostly due to the color-density relation. While the galaxy companion rate (N{sub c}) is observed to increase with overdensity, using N-body simulations, we find that the fraction of pairs that will eventually merge decreases with the local density, predominantly because interlopers are more common in dense environments. After taking into account the merger probability of pairs as a function of local density, we find only marginal environment dependence of the galaxy merger rate for wet mergers. On the other hand, the dry and mixed merger rates increase rapidly with local density due to the increased population of red galaxies in dense environments, implying that the dry and mixed mergers are most effective in overdense regions. We also find that the environment distribution of K+A galaxies is similar to that of wet mergers alone and of wet+mixed mergers, suggesting a possible connection between K+A galaxies and wet and/or wet+mixed mergers. Based on our results, we therefore expect that the properties, including structures and masses, of red-sequence galaxies should be different between those in underdense regions and those in overdense regions since the dry mergers are significantly more important in dense environments. We conclude that, as early as z {approx} 1, high-density regions are the preferred environment in which dry mergers occur, and that present-day red-sequence galaxies in overdense environments have, on average, undergone 1.2 {+-} 0.3 dry mergers since this time, accounting for (38 {+-} 10)% of their mass accretion in the last 8 billion years. The main uncertainty in this finding is the conversion from the pair fraction to the galaxy merger rate, which is possibly as large as a factor of 2. Our findings

  11. The VIMOS Ultra-Deep Survey (VUDS): fast increase in the fraction of strong Lyman-α emitters from z = 2 to z = 6

    NASA Astrophysics Data System (ADS)

    Cassata, P.; Tasca, L. A. M.; Le Fèvre, O.; Lemaux, B. C.; Garilli, B.; Le Brun, V.; Maccagni, D.; Pentericci, L.; Thomas, R.; Vanzella, E.; Zamorani, G.; Zucca, E.; Amorin, R.; Bardelli, S.; Capak, P.; Cassarà, L. P.; Castellano, M.; Cimatti, A.; Cuby, J. G.; Cucciati, O.; de la Torre, S.; Durkalec, A.; Fontana, A.; Giavalisco, M.; Grazian, A.; Hathi, N. P.; Ilbert, O.; Moreau, C.; Paltani, S.; Ribeiro, B.; Salvato, M.; Schaerer, D.; Scodeggio, M.; Sommariva, V.; Talia, M.; Taniguchi, Y.; Tresse, L.; Vergani, D.; Wang, P. W.; Charlot, S.; Contini, T.; Fotopoulou, S.; Koekemoer, A. M.; López-Sanjuan, C.; Mellier, Y.; Scoville, N.

    2015-01-01

    Aims: The aim of this work is to constrain the evolution of the fraction of strong Lyα emitters among UV selected star-forming galaxies at 2 Deep Survey (VUDS) to build an unique, complete, and unbiased sample of ~4000 spectroscopically confirmed star-forming galaxies at 2 25 Å to increase from ~5% at z ~ 2 to ~30% at z ~ 6, with the increase being stronger beyond z ~ 4. We observe no difference, for the narrow range of UV luminosities explored in this work, between the fraction of strong Lyα emitters among galaxies fainter or brighter than M*FUV, although the fraction for the faint galaxies evolves faster, at 2

  12. Discovering extremely compact and metal-poor, star-forming dwarf galaxies out to z ~ 0.9 in the VIMOS Ultra-Deep Survey

    NASA Astrophysics Data System (ADS)

    Amorín, R.; Sommariva, V.; Castellano, M.; Grazian, A.; Tasca, L. A. M.; Fontana, A.; Pentericci, L.; Cassata, P.; Garilli, B.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Thomas, R.; Vanzella, E.; Zamorani, G.; Zucca, E.; Bardelli, S.; Capak, P.; Cassará, L. P.; Cimatti, A.; Cuby, J. G.; Cucciati, O.; de la Torre, S.; Durkalec, A.; Giavalisco, M.; Hathi, N. P.; Ilbert, O.; Lemaux, B. C.; Moreau, C.; Paltani, S.; Ribeiro, B.; Salvato, M.; Schaerer, D.; Scodeggio, M.; Talia, M.; Taniguchi, Y.; Tresse, L.; Vergani, D.; Wang, P. W.; Charlot, S.; Contini, T.; Fotopoulou, S.; López-Sanjuan, C.; Mellier, Y.; Scoville, N.

    2014-08-01

    We report the discovery of 31 low-luminosity (-14.5 ≳ MAB(B) ≳ -18.8), extreme emission line galaxies (EELGs) at 0.2 ≲ z ≲ 0.9 identified by their unusually high rest-frame equivalent widths (100 ≤ EW[O iii] ≤ 1700 Å) as part of the VIMOS Ultra Deep Survey (VUDS). VIMOS optical spectra of unprecedented sensitivity (IAB ~ 25 mag) along with multiwavelength photometry and HST imaging are used to investigate spectrophotometric properties of this unique sample and to explore, for the first time, the very low stellar mass end (M⋆ ≲ 108M⊙) of the luminosity-metallicity (LZR) and mass-metallicity (MZR) relations at z < 1. Characterized by their extreme compactness (R50 < 1 kpc), low stellar mass and enhanced specific star formation rates (sSFR = SFR/M⋆ ~ 10-9-10-7 yr-1), the VUDS EELGs are blue dwarf galaxies likely experiencing the first stages of a vigorous galaxy-wide starburst. Using Te-sensitive direct and strong-line methods, we find that VUDS EELGs are low-metallicity (7.5 ≲ 12 + log (O/H) ≲ 8.3) galaxies with high ionization conditions (log (qion) ≳ 8 cm s-1), including at least three EELGs showing Heiiλ 4686 Å emission and four extremely metal-poor (≲10% solar) galaxies. The LZR and MZR followed by VUDS EELGs show relatively large scatter, being broadly consistent with the extrapolation toward low luminosity and mass from previous studies at similar redshift. However, we find evidence that galaxies with younger and more vigorous star formation - as characterized by their larger EWs, ionization and sSFR - tend to be more metal poor at a given stellar mass. Based on data obtained with the European Southern Observatory Very Large Telescope, Paranal, Chile, under Large Program 185.A-0791.Figure A.1 is available in electronic form at http://www.aanda.orgTables 1 and 2 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/568/L8

  13. A deep x-ray survey of the Pleiades cluster and the B6-A3 main sequence stars in Orion

    NASA Technical Reports Server (NTRS)

    Caillault, Jean-Pierre

    1993-01-01

    We have obtained deep ROSAT images of three regions within the Pleiades open cluster. We have detected 317 X-ray sources in these ROSAT PSPC images, 171 of which we associate with certain probable members of the Pleiades cluster. We detect nearly all Pleiades members with spectral types later than G0 and within 25 arcminutes of our three field centers where our sensitivity is highest. This has allowed us to derive for the first time the luminosity function for the G, K, and M dwarfs of an open cluster without the need to use statistical techniques to account for the presence of upper limits in the data sample. Because of our high X-ray detection frequency down to the faint limit of the optical catalog, we suspect that some of our unidentified X-ray sources are previously unknown, very low-mass members of the Pleiades. A large fraction of the Pleiades members detected with ROSAT have published rotational velocities. Plots of L(sub x)/L(sub bol) versus spectroscopic rotational velocity show tightly correlated 'saturation' type relations for stars with (B - V)(sub O) greater than 0.60. For each of several color ranges, X-ray luminosities rise rapidly with increasing rotation rate until v sin i approximately equals 15 km/s, and then remain essentially flat for rotation rates up to at least v sin i approximately equal to 100 km/s. The dispersion in rotation among low-mass stars in the Pleiades is by far the dominant contributor to the dispersion in L(subx) at a given mass. Only about 35 percent of the B.A. and early F stars in the Pleiades are detected as X-ray sources in our survey. There is no correlation between X-ray flux and rotation for these stars. The X-ray luminosity function for the early-type Pleiades stars appears to be bimodal, with only a few exceptions. We either detect these stars at fluxes in the range found for low-mass stars or we derive X-ray limits below the level found for most Pleiades dwarfs. The X-ray spectra for the early-type Pleiades stars

  14. The 7 Ms Chandra Deep Field-South Survey: Cosmic Black-Hole Growth is Mainly Linked to Host-Galaxy Stellar Mass

    NASA Astrophysics Data System (ADS)

    Brandt, W. Niel; Yang, Guang; Chen, Chien-Ting; Vito, Fabio

    2017-08-01

    The Chandra exposure on the Chandra Deep Field-South (CDF-S) has recently been increased to 7 Ms, allowing unmatched X-ray and multiwavelength characterization of cosmic black-hole growth in active galactic nuclei (AGNs). We have used these data to investigate the dependence of black-hole accretion rate (BHAR) on host-galaxy star formation rate (SFR) and stellar mass (M*) at z = 0.5-2. Our sample consists of 18,000 galaxies with SFR and M* measurements, and we use sample-mean BHAR for these galaxies to approximate their long-term average BHAR. Our sample-mean BHARs are derived from the CDF-S observations via both direct spectral analysis and stacking. The average BHAR is correlated positively with both SFR and M*, and the BHAR-SFR and BHAR-M* relations can both be described acceptably by linear models with a slope of unity. However, according to partial-correlation analyses, BHAR is correlated more strongly with M* than SFR. This result indicates that M* is the primary host-galaxy property related to black-hole growth, and the well-known BHAR-SFR relation is largely a secondary effect due to the "star-forming main sequence". Among our sources, massive galaxies have significantly higher BHAR/SFR ratios than less-massive galaxies, indicating the former have higher black-hole fueling efficiency and/or higher SMBH occupation fraction than the latter; e.g., the deeper potential wells in higher mass galaxies may promote black-hole accretion and counteract AGN/supernova feedback. Our results can naturally explain the observed proportionality between MBH and M* for local giant ellipticals, and suggest their MBH/M* ratios are higher than those of local star-forming galaxies. Finally, prospects for extending this work will be discussed; e.g., by further investigating the redshift evolution of the primary BHAR-M* relation and measuring this relation for even higher values of M*, above ~ 1011 solar masses, using wide-field X-ray surveys.

  15. VIMOS Ultra-Deep Survey (VUDS): IGM transmission towards galaxies with 2.5 < z < 5.5 and the colour selection of high-redshift galaxies

    NASA Astrophysics Data System (ADS)

    Thomas, R.; Le Fèvre, O.; Le Brun, V.; Cassata, P.; Garilli, B.; Lemaux, B. C.; Maccagni, D.; Pentericci, L.; Tasca, L. A. M.; Zamorani, G.; Zucca, E.; Amorin, R.; Bardelli, S.; Cassarà, L.; Castellano, M.; Cimatti, A.; Cucciati, O.; Durkalec, A.; Fontana, A.; Giavalisco, M.; Grazian, A.; Hathi, N. P.; Ilbert, O.; Paltani, S.; Pforr, J.; Ribeiro, B.; Schaerer, D.; Scodeggio, M.; Sommariva, V.; Talia, M.; Tresse, L.; Vanzella, E.; Vergani, D.; Capak, P.; Charlot, S.; Contini, T.; Cuby, J. G.; de la Torre, S.; Dunlop, J.; Fotopoulou, S.; Koekemoer, A.; López-Sanjuan, C.; Mellier, Y.; Salvato, M.; Scoville, N.; Taniguchi, Y.; Wang, P. W.

    2017-01-01

    The observed UV rest-frame spectra of distant galaxies are the result of their intrinsic emission combined with absorption along the line of sight produced by the inter-galactic medium (IGM). Here we analyse the evolution of the mean IGM transmission Tr(Lyα) and its dispersion along the line of sight for 2127 galaxies with 2.5 < z < 5.5 in the VIMOS Ultra Deep Survey (VUDS). We fitted model spectra combined with a range of IGM transmission to the galaxy spectra using the spectral fitting algorithm GOSSIP+. We used these fits to derive the mean IGM transmission towards each galaxy for several redshift slices from z = 2.5 to z = 5.5. We found that the mean IGM transmission defined as Tr(Lyα) = e- τ (with τ as the HI optical depth) is 79%, 69%, 59%, 55%, and 46% at redshifts 2.75, 3.22, 3.70, 4.23, and 4.77, respectively. We compared these results to measurements obtained from quasar lines of sight and found that the IGM transmission towards galaxies is in excellent agreement with quasar values up to redshift z 4. We found tentative evidence for a higher IGM transmission at z ≥ 4 compared to results from QSOs, but a degeneracy between dust extinction and IGM prevents us from firmly concluding whether the internal dust extinction for star-forming galaxies at z > 4 takes a mean value significantly in excess of E(B-V) > 0.15. Most importantly, we found a large dispersion of IGM transmission along the lines of sight towards distant galaxies with 68% of the distribution within 10 to 17% of the median value in δz = 0.5 bins, similar to what is found on the lines of sight towards QSOs. We demonstrate that taking this broad range of IGM transmission into account is important when selecting high-redshift galaxies based on their colour properties (e.g. LBG or photometric redshiftselection) because failing to do so causes a significant incompleteness in selecting high-redshift galaxy populations. We finally discuss the observed IGM properties and speculate that the broad

  16. The Vimos VLT Deep Survey. Stellar mass segregation and large-scale galaxy environment in the redshift range 0.2 < z < 1.4

    NASA Astrophysics Data System (ADS)

    Scodeggio, M.; V