Browsing Citations Only by Author "O'Dea, Christopher"

Now showing items 1-18 of 18

    • A comparative HST imaging study of the host galaxies of radio-quiet quasars, radio-loud quasars and radio galaxies: I 

      McLure, Ross; Dunlop, James; Kukula, Marek; Baum, Stefi; O'Dea, Christopher; Hughes, David (Blackwell Publishing, 1999-09)
      We present the first results from a major HST WFPC2 imaging study aimed at providing the first statistically meaningful comparison of the morphologies, luminosities, scalelengths and colours of the host galaxies of radio-quiet ...

    • Constraints on ultraviolet absorption in the intracluster medium of Abell 1030 

      Koekemoer, Anton; O'Dea, Christopher; Baum, Stefi; Sarazin, Craig; Owen, Frazer; Ledlow, Michael (Astrophysical Journal, 1998-12-01)
      We present results from an extensive HST spectroscopic search for UV absorption lines in the spectrum of the quasar B2 1028+313, which is associated with the central dominant galaxy in the cluster Abell 1030 (z=0.178). ...

    • A direct image of the obscuring disk surrounding an active galactic nucleus 

      Gallimore, Jack; Baum, Stefi; O'Dea, Christopher (Nature, 1997-08-28)
      Active galactic nuclei (AGN) are generally accepted to be powered by the release of gravitational energy in a compact accretion disk surrounding a massive black hole. Such disks are also necessary to collimate powerful ...

    • The extended blue continuum and line emission around the Central Radio Galaxy in Abell 2597 

      Koekemoer, Anton; O'Dea, Christopher; Sarazin, Craig; McNamara, Brian; Donahue, Megan; Voit, G. Mark; Baum, Stefi; Gallimore, Jack (American Astronomical Society, 1999-11-10)
      We present results from detailed imaging of the centrally dominant radio elliptical galaxy in the cooling flow cluster Abell 2597, using data obtained with the Wide Field and Planetary Camera 2 (WFPC2) on the Hubble Space ...

    • HI absorption in the gigamaser galaxy TXS 2226-184 and the relation between HI absorption and water emission 

      Taylor, Gregory; Peck, Alison; Henkel, Christian; Falcke, Heino; Mundell, Carole; O'Dea, Christopher; Baum, Stefi; Gallimore, Jack (American Astronomical Society, 2002-07-20)
      We report on the discovery of H i in absorption toward the gigamaser galaxy TXS 2226-184 using the Very Large Array. The absorption appears to consist of two components—one with a width of 125 km s^-1 and one broader (420 ...

    • High-resolution radio observations of Seyfert galaxies in the extended 12-micron sample - I. The Observations 

      Thean, Andy; Pedlar, Alan; Kukula, Marek; Baum, Stefi; O'Dea, Christopher (Blackwell Publishing, 2000-05)
      We present 8.4 GHz VLA A–configuration observations of 87 sources from the mid–infrared–selected AGN sample of Rush et al. (1993). These 0.25 arcsec resolution observations allow elongated radio structures tens of parsecs ...

    • High-resolution radio observations of Seyfert galaxies in the extended 12-micron sample - II. The Properties of compact radio components 

      Thean, Andy; Pedlar, Alan; Kukula, Marek; Baum, Stefi; O'Dea, Christopher (Blackwell Publishing, 2001-08)
      We discuss the properties of compact nuclear radio components in Seyfert galaxies from the extended 12 µm AGN sample of Rush et al. (1993). Our main results can be summarised as follows. Type 1 and type 2 Seyferts produce ...

    • The host galaxies of luminous quasars 

      Floyd, David; Kukula, Marek; Dunlop, James; McLure, Ross; Miller, Lance; Percival, Will; Baum, Stefi; O'Dea, Christopher (Blackwell Publishing, 2004-11)
      We present the results of a deep HST/WFPC2 imaging study of 17 quasars at z~=0.4, designed to determine the properties of their host galaxies. The sample consists of quasars with absolute magnitudes in the range −24 ≥ MV ...

    • A NICMOS imaging study of high-z quasar host galaxies 

      Kukula, Marek; Dunlop, James; McClure, Ross; Miller, Lance; Percival, Will; Baum, Stefi; O'Dea, Christopher (Blackwell Publishing, 2001-10)
      We present the first results from a major Hubble Space Telescope programme designed to investigate the cosmological evolution of quasar host galaxies from z~=2 to the present day. Here we describe J and H-band NICMOS ...

    • The Parsec-scale radio structure of NGC 1068 and the nature of the nuclear radio source 

      Gallimore, Jack; Baum, Stefi; O'Dea, Christopher (American Astronomical Society, 2004-10-01)
      We present sensitive, multifrequency Very Long Baseline Array (VLBA2) images of the nuclear radio sources of NGC 1068. At 5 GHz and 8.4 GHz, the radio continuum source S1, argued to mark the location of the hidden active ...

    • Quasars, their host galaxies, and their central black holes 

      Dunlop, James; McLure, Ross; Kukula, Marek; Baum, Stefi; O'Dea, Christopher; Hughes, David (Blackwell Publishing, 2003-04-09)
      We present the final results from our deep HST imaging study of the host galaxies of radio-quiet quasars (RQQs), radio-loud quasars (RLQs) and radio galaxies (RGs). We describe and analyze new WFPC2 R-band observations for ...

    • The Radio-optical jet in NGC 3862 from parsec to sub-kiloparsec scales 

      Lara, Luisa; Feretti, Luigina; Giovannini, Gabriele; Baum, Stefi; Cotton, William; O'Dea, Christopher; Venturi, Tiziana (Astrophysical Journal, 1999-03-01)
      We have observed the radio source in NGC 3862 (3C 264) simultaneously with the European VLBI network and the MERLIN arrays, obtaining detailed images of its radio structure from parsec to subkiloparsec scales. 3C 264 shows ...

    • Star formation in hosts of young radio galaxies 

      Labiano, Alvaro; O'Dea, Christopher; Barthel, Peter; de Vries, Wim; Baum, Stefi (QSO Hosts: Evolution and Environment, 2005-08)
      We present near ultraviolet imaging with the Hubble Space Telescope Advanced Camera for Surveys, targeting young radio galaxies (Gigahertz Peaked Spectrum and Compact Steep Spectrum sources), in search of star formation ...

    • The warped nuclear disk of radio galaxy 3C 449 

      Tremblay, Grant; Quillen, Alice; Floyd, David; Noel-Storr, Jacob; Baum, Stefi; Axon, David; O'Dea, Christopher; Chiaberge, Marco; Macchetto, Duccio; Sparks, William; Miley, George; Capetti, Alessandro; Madrid, Juan; Perlman, Eric (Astrophysical Journal, 2006)
      Among radio galaxies containing nuclear dust disks, the bipolar jet axis is generally observed to be perpendicular to the disk major axis. The FR I radio source 3C 449 is an outlier to this statistical majority, as it ...

    • X-ray properties of B2 1028+313: a quasar at the center of the Abell cluster A1030 

      Sarazin, Craig; Koekemoer, Anton; Baum, Stefi; O'Dea, Christopher; Owen, Frazer; Wise, Michael (American Astronomical Society, 1999-01-01)
      X-ray observationswith the ROSATHRI and with ASCA are presented for the nearby radio quasar B2 1028+313, which is located in the cD galaxy at the center of the Abell cluster A1030. We also analyze archival ROSAT ...