Browsing by Author "Salvato, M."

Now showing 1 - 15 of 15
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    An ALMA survey of submillimetre galaxies in the COSMOS field : The extent of the radio-emitting region revealed by 3 GHz imaging with the Very Large Array
    (2017) Miettinen, O.; Novak, M.; Smolčić, V.; Delvecchio, I.; Aravena, M.; Brisbin, D.; Karim, A.; Murphy, E.; Schinnerer, E.; Padilla, Nelson; Albrecht, M.; Aussel, H.; Bertoldi, F.; Capak, P.; Casey, C.; Civano, F.; Hayward, C.; Herrera Ruiz, N.; Ilbert, O.; Jiang, C.; Laigle, C.; Le Fèvre, O.; Magnelli, B.; Marchesi, S.; McCracken, H.; Middelberg, E.; Muñoz Arancibia, A.; Navarrete, F.; Riechers, D.; Salvato, M.; Scott, K.; Sheth, K.; Tasca, L.; Bondi, M.; Zamorani, G.
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    Non-linearity and environmental dependence of the star-forming galaxies main sequence
    (2016) Erfanianfar, G.; Popesso, P.; Finoguenov, A.; Wilman, D.; Wuyts, S.; Biviano, A.; Salvato, M.; Mirkazemi, M.; Morselli, L.; Bauer, Franz Erik; Ziparo, F.; Nandra, K.; Lutz, D.; Elbaz, D.; Tanaka, M.; Altieri, M.
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    Reversal or no reversal : The evolution of the star formation rate-density relation up to z ~ 1.6
    (2013) Bauer, Franz Erik; Ziparo, F.; Popesso, P.; Finoguenov, A.; Biviano, A.; Wuyts, S.; Wilman, D.; Salvato, M.; Tanaka, M.; Bauer, Franz Erik
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    SPIDERS : overview of the X-ray galaxy cluster follow-up and the final spectroscopic data release
    (2020) Clerc, N.; Kirkpatrick, C. C.; Finoguenov, A.; Capasso, R.; Comparat, J.; Damsted, S.; Furnell, K.; Kukkola, A. E.; Chitham, J. I.; Padilla, Nelson; Merloni, A.; Salvato, M.; Gueguen, A.; Dwelly, T.; Collins, C.; Saro, A.; Erfanianfar, G.; Schneider, D. P.; Brownstein, J.; Mamon, G. A.; Jullo, E.; Bizyaev, D.
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    SPIDERS: selection of spectroscopic targets using AGN candidates detected in all-sky X-ray surveys
    (OXFORD UNIV PRESS, 2017) Dwelly, T.; Salvato, M.; Merloni, A.; Brusa, M.; Buchner, J.; Anderson, S. F.; Boller, Th.; Brandt, W. N.; Budavari, T.; Clerc, N.; Coffey, D.; Del Moro, A.; Georgakakis, A.; Green, P. J.; Jin, C.; Menzel, M. L.; Myers, A. D.; Nandra, K.; Nichol, R. C.; Ridl, J.; Schwope, A. D.; Simm, T.
    SPIDERS (SPectroscopic IDentification of eROSITA Sources) is a Sloan Digital Sky Survey IV (SDSS-IV) survey running in parallel to the Extended Baryon Oscillation Spectroscopic Survey (eBOSS) cosmology project. SPIDERS will obtain optical spectroscopy for large numbers of X-ray-selected active galactic nuclei (AGN) and galaxy cluster members detected in wide-area eROSITA, XMM-Newton and ROSAT surveys. We describe the methods used to choose spectroscopic targets for two sub-programmes of SPIDERS X-ray selected AGN candidates detected in the ROSAT All Sky and the XMM-Newton Slew surveys. We have exploited a Bayesian cross-matching algorithm, guided by priors based on mid-IR colourmagnitude information from the Wide-field Infrared Survey Explorer survey, to select the most probable optical counterpart to each X-ray detection. We empirically demonstrate the high fidelity of our counterpart selection method using a reference sample of bright welllocalized X-ray sources collated from XMM-Newton, Chandra and Swift-XRT serendipitous catalogues, and also by examining blank-sky locations. We describe the down-selection steps which resulted in the final set of SPIDERS-AGN targets put forward for spectroscopy within the eBOSS/TDSS/SPIDERS survey, and present catalogues of these targets. We also present catalogues of similar to 12 000 ROSAT and similar to 1500 XMM-Newton Slew survey sources that have existing optical spectroscopy from SDSS-DR12, including the results of our visual inspections. On completion of the SPIDERS programme, we expect to have collected homogeneous spectroscopic redshift information over a footprint of similar to 7500 deg(2) for > 85 per cent of the ROSAT and XMM-Newton Slew survey sources having optical counterparts in the magnitude range 17 < r < 22.5, producing a large and highly complete sample of bright X-ray-selected AGN suitable for statistical studies of AGN evolution and clustering.
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    The Chandra COSMOS Legacy survey: optical/IR identifications
    (2016) Marchesi, Stefano; Treister, Ezequiel; Civano, Francesca; Elvis, Martin; Salvato, M.; Brusa, Marcella; Comastri, A.; Gilli, R.; Hasinger, G.; Lanzuisi, G.; Miyaji, T.; Urry, C. Megan
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    The Chandra COSMOS-Legacy Survey: The z>3 Sample
    (2016) Marchesi, Stefano; Treister, Ezequiel; Civano, Francesca; Salvato, M.; Shankar, F.; Comastri, A.; Elvis, Martin; Lanzuisi, G.; Trakhtenbrot, Benny; Vignali, C.; Zamorani, G.; Allevato, Viola
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    The evolution of star formation activity in galaxy groups
    (2014) Erfanianfar, G.; Popesso, P.; Finoguenov, A.; Wuyts, S.; Wilman, D.; Biviano, A.; Ziparo, F.; Salvato, M.; Nandra, K.; Bauer, Franz Erik
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    The Extended Chandra Deep Field-South Survey: Optical Spectroscopy of Faint X-ray Sources with the VLT and Keck
    (2006) Silverman, J. D.; Treister, Ezequiel; Mainieri, V.; Salvato, M.; Hasinger, G.; Bergeron, J.; Capak, P.; Szokoly, G.; Finoguenov, A.; Gilli, R.; Rosati, P.
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    The Hunt for Red Quasars: Luminous Obscured Black Hole Growth Unveiled in the Stripe 82 X-Ray Survey
    (2017) LaMassa, Stephanie M.; Lira, Paulina; Treister, Ezequiel; Glikman, Eilat; Brusa, Marcella; Rigby, Jane R.; Ananna, Tonima; Stern, Daniel.; Urry, C. Megan; Salvato, M.; Alexandroff, Rachael
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    The incidence of obscuration in active galactic nuclei.
    (2014) Merloni, A.; Treister, Ezequiel; Bongiorno, A.; Brusa, Marcella; Iwasawa, K.; Mainieri, V.; Magnelli, B.; Salvato, M.; Berta, S.; Cappelluti N; Comastri, A.
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    The Obscured Fraction of Active Galactic Nuclei in the XMM-COSMOS Survey: A Spectral Energy Distribution Perspective
    (2013) Lusso, E.; Treister, Ezequiel; Hennawi, J. F.; Comastri, A.; Zamorani, G.; Richards, G. T.; Vignali, C.; Schawinski, Kevin; Salvato, M.; Gilli, R.
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    The XMM-Newton Wide-field Survey in the Cosmos Field (XMM-COSMOS): Demography and Multiwavelength Properties of Obscured and Unobscured Luminous Active Galactic Nuclei
    (2010) Brusa, Marcella; Treister, Ezequiel; Civano, Francesca; Comastri, A.; Miyaji, T.; Salvato, M.; Zamorani, G.; Cappelluti, N; Fiore, F.; Hasinger, G.; Mainieri, V.
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    X-ray constraints on the fraction of obscured active galactic nuclei at high accretion luminosities
    (OXFORD UNIV PRESS, 2017) Georgakakis, A.; Salvato, M.; Liu, Z.; Buchner, J.; Brandt, W. N.; Ananna, T. Tasnim; Schulze, A.; Shen, Yue; LaMassa, S.; Nandra, K.; Merloni, A.; McGreer, I. D.
    The wide-area XMM-XXL X-ray survey is used to explore the fraction of obscured active galactic nuclei (AGNs) at high accretion luminosities, L-X(2-10 keV) greater than or similar to 10(44) erg s(-1), and out to redshift z approximate to 1.5. The sample covers an area of about 14 deg(2) and provides constraints on the space density of powerful AGNs over a wide range of neutral hydrogen column densities extending beyond the Compton-thick limit, N-H approximate to 10(24) cm(-2). The fraction of obscured Compton-thin (N-H = 10(22) - 10(24) cm(-2)) AGNs is estimated to be approximate to 0.35 for luminosities L-X(2-10 keV) > 10(44) erg s(-1), independent of redshift. For less luminous sources, the fraction of obscured Compton-thin AGNs increases from 0.45 +/- 0.10 at z = 0.25 to 0.75 +/- 0.05 at z = 1.25. Studies that select AGNs in the infrared via template fits to the observed spectral energy distribution of extragalactic sources estimate space densities at high accretion luminosities consistent with the XMM-XXL constraints. There is no evidence for a large population of AGNs (e.g. heavily obscured) identified in the infrared and missed at X-ray wavelengths. We further explore the mid-infrared colours of XMM-XXL AGNs as a function of accretion luminosity, column density and redshift. The fraction of XMM-XXL sources that lie within the mid-infrared colour wedges defined in the literature to select AGNs is primarily a function of redshift. This fraction increases from about 20-30 per cent at z = 0.25 to about 50-70 per cent at z = 1.5.
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    XZ: Deriving redshifts from X-ray spectra of obscured AGN
    (2018) Simmonds, C.; Buchner, J.; Salvato, M.; Hsu, L-T; Bauer, Franz Erik