Riguccini, L. and Le Floc'h, E. and Mullaney, J. R. and Menéndez-Delmestre, K. and Aussel, H. and Berta, S. and Calanog, J. and Capak, P. and Cooray, A. and Ilbert, O. and Kartaltepe, J. and Koekemoer, A. and Lutz, D. and Magnelli, B. and McCracken, H. and Oliver, S. and Roseboom, I. and Salvato, M. and Sanders, D. and Scoville, N. and Taniguchi, Y. and Treister, E. (2015) The composite nature of Dust-Obscured Galaxies (DOGs) at z ∼ 2–3 in the COSMOS field – I. A far-infrared view. Monthly Notices of the Royal Astronomical Society, 452 (1). pp. 470-485. ISSN 0035-8711. http://resolver.caltech.edu/CaltechAUTHORS:20151002-142311846
- Published Version
See Usage Policy.
Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20151002-142311846
Dust-Obscured Galaxies (DOGs) are bright 24 μm-selected sources with extreme obscuration at optical wavelengths. They are typically characterized by a rising power-law continuum of hot dust (T_D ∼ 200–1000 K) in the near-IR indicating that their mid-IR luminosity is dominated by an active galactic nucleus (AGN). DOGs with a fainter 24 μm flux display a stellar bump in the near-IR and their mid-IR luminosity appears to be mainly powered by dusty star formation. Alternatively, it may be that the mid-IR emission arising from AGN activity is dominant but the torus is sufficiently opaque to make the near-IR emission from the AGN negligible with respect to the emission from the host component. In an effort to characterize the astrophysical nature of the processes responsible for the IR emission in DOGs, this paper exploits Herschel data (PACS + SPIRE) on a sample of 95 DOGs within the COSMOS field. We derive a wealth of far-IR properties (e.g. total IR luminosities; mid-to-far-IR colours; dust temperatures and masses) based on spectral energy distribution fitting. Of particular interest are the 24 μm-bright DOGs (F_(24) μm > 1 mJy). They present bluer far-IR/mid-IR colours than the rest of the sample, unveiling the potential presence of an AGN. The AGN contribution to the total 8–1000 μm flux increases as a function of the rest-frame 8 μm-luminosity irrespective of the redshift. This confirms that faint DOGs (L_8 μm < 10^(12) L_⊙) are dominated by star formation while brighter DOGs show a larger contribution from an AGN.
|Additional Information:||© 2015 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. Accepted 2015 June 8. Received 2015 May 15. In original form 2014 September 23. First published online July 3, 2015. COSMOS is based on observations with the NASA/ESA HST, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555; also based on data collected at: the Subaru Telescope, which is operated by the National Astronomical Observatory of Japan; XMM–Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA; the European Southern Observatory, Chile; Kitt Peak National Observatory, Cerro Tololo Inter-American Observatory, and the National Optical Astronomy Observatory, which are operated by the Association of Universities for Research in Astronomy (AURA), Inc., under cooperative agreement with the National Science Foundation; the National Radio Astronomy Observatory, which is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities,Inc; and the Canada–France–Hawaii Telescope, operated by the National Research Council of Canada, the Centre National de la Recherche Scientifique de France, and the University of Hawaii. PACS has been developed by a consortium of institutes led by MPE (Germany) and including UVIE (Austria); KU Leuven, CSL, IMEC (Belgium); CEA, LAM (France); MPIA (Germany); INAF-IFSI/OAA/OAP/OAT, LENS, SISSA (Italy); IAC (Spain). This development has been supported by the funding agencies BMVIT (Austria), ESA-PRODEX (Belgium), CEA/CNES (France), DLR (Germany), ASI/INAF (Italy), and CICYT/MCYT (Spain). SPIRE has been developed by a consortium of institutes led by Cardiff University (UK) and including University of Lethbridge (Canada), NAOC (China), CEA, LAM (France), IFSI, University of Padua (Italy), IAC (Spain), Stockholm Observatory (Sweden), Imperial College London, RAL, UCL-MSSL, UKATC, University of Sussex (UK), Caltech, JPL, NHSC, University of Colorado (USA). This development has been supported by national funding agencies: CSA (Canada); NAOC (China); CEA, CNES, CNRS (France); ASI (Italy); MCINN (Spain); SNSB (Sweden); STFC, UKSA (UK) and NASA (USA). SPIRE has been developed by a consortium of institutes led by Cardiff Univ. (UK) and including Univ. Lethbridge (Canada); NAOC (China); CEA, LAM (France); IFSI, Univ. Padua (Italy); IAC (Spain); Stockholm Observatory (Sweden); Imperial College London, RAL, UCL-MSSL, UKATC, Univ. Sussex (UK); Caltech, JPL, NHSC, Univ. Colorado (USA). This development has been supported by national funding agencies: CSA (Canada); NAOC (China); CEA, CNES, CNRS (France); ASI (Italy); MCINN (Spain); SNSB (Sweden); STFC, UKSA (UK); and NASA (USA).|
|Group:||Infrared Processing and Analysis Center (IPAC), COSMOS|
|Subject Keywords:||galaxies: high-redshift; cosmology: observations; infrared: galaxies|
|Official Citation:||L. Riguccini, E. Le Floc'h, J. R. Mullaney, K. Menéndez-Delmestre, H. Aussel, S. Berta, J. Calanog, P. Capak, A. Cooray, O. Ilbert, J. Kartaltepe, A. Koekemoer, D. Lutz, B. Magnelli, H. McCracken, S. Oliver, I. Roseboom, M. Salvato, D. Sanders, N. Scoville, Y. Taniguchi, and E. Treister The composite nature of Dust-Obscured Galaxies (DOGs) at z ∼ 2–3 in the COSMOS field – I. A far-infrared view MNRAS (September 01, 2015) Vol. 452 470-485 doi:10.1093/mnras/stv1297 First published online July 3, 2015|
|Usage Policy:||No commercial reproduction, distribution, display or performance rights in this work are provided.|
|Deposited By:||George Porter|
|Deposited On:||05 Oct 2015 21:09|
|Last Modified:||07 Dec 2016 18:34|
Repository Staff Only: item control page