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Title: HerMES: Spectral energy distributions of submillimeter galaxies at z > 4

We present a study of the infrared properties for a sample of seven spectroscopically confirmed submillimeter galaxies (SMGs) at z > 4.0. By combining ground-based near-infrared, Spitzer IRAC and MIPS, Herschel SPIRE, and ground-based submillimeter/millimeter photometry, we construct their spectral energy distributions (SEDs) and a composite model to fit the SEDs. The model includes a stellar emission component at λ{sub rest} < 3.5 μm, a hot dust component peaking at λ{sub rest} ∼ 5 μm, and cold dust component which becomes significant for λ{sub rest} > 50 μm. Six objects in the sample are detected at 250 and 350 μm. The dust temperatures for the sources in this sample are in the range of 40-80 K, and their L {sub FIR} ∼ 10{sup 13} L {sub ☉} qualifies them as hyper-luminous infrared galaxies. The mean FIR-radio index for this sample is around (q) = 2.2 indicating no radio excess in their radio emission. Most sources in the sample have 24 μm detections corresponding to a rest-frame 4.5 μm luminosity of Log{sub 10}(L {sub 4.5}/L {sub ☉}) = 11 ∼ 11.5. Their L {sub 4.5}/L {sub FIR} ratios are very similar to those of starburst-dominated SMGs at z ∼ 2. Themore » L {sub CO} – L {sub FIR} relation for this sample is consistent with that determined for local ULIRGs and SMGs at z ∼ 2. We conclude that SMGs at z > 4 are hotter and more luminous in the FIR but otherwise very similar to those at z ∼ 2. None of these sources show any sign of the strong QSO phase being triggered.« less
 [1] ; ;  [2] ; ;  [3] ; ;  [4] ;  [5] ;  [6] ;  [7] ;  [8] ;  [9] ;  [10] ; ; ;  [11] ; ;  [12] ;  [13] ;  [14] more »; « less
  1. National Astronomical Observatories of China, Chinese Academy of Sciences, Beijing 100012 (China)
  2. Department of Physics, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom)
  3. Astrophysics Group, Imperial College London, Blackett Laboratory, Prince Consort Road, London SW7 2AZ (United Kingdom)
  4. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
  5. California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States)
  6. Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)
  7. Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom)
  8. Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States)
  9. Department of Physics, Virginia Tech, Blacksburg, VA 24061 (United States)
  10. Department of Astrophysical and Planetary Sciences, CASA 389-UCB, University of Colorado, Boulder, CO 80309 (United States)
  11. Astronomy Center, Department of Physics and Astronomy, University of Sussex, Falmer, Brighton BN1 9QH (United Kingdom)
  12. Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT (United Kingdom)
  13. Astronomy Department, California Institute of Technology, MC 249-17, 1200 East California Boulevard, Pasadena, CA 91125 (United States)
  14. Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill Edinburgh, EH9 3HJ (United Kingdom)
Publication Date:
OSTI Identifier:
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 784; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States