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Title: HERSCHEL-ATLAS: A BINARY HyLIRG PINPOINTING A CLUSTER OF STARBURSTING PROTOELLIPTICALS

Panchromatic observations of the best candidate hyperluminous infrared galaxies from the widest Herschel extragalactic imaging survey have led to the discovery of at least four intrinsically luminous z = 2.41 galaxies across an Almost-Equal-To 100 kpc region-a cluster of starbursting protoellipticals. Via subarcsecond interferometric imaging we have measured accurate gas and star formation surface densities. The two brightest galaxies span {approx}3 kpc FWHM in submillimeter/radio continuum and CO J = 4-3, and double that in CO J = 1-0. The broad CO line is due partly to the multitude of constituent galaxies and partly to large rotational velocities in two counter-rotating gas disks-a scenario predicted to lead to the most intense starbursts, which will therefore come in pairs. The disks have M{sub dyn} of several Multiplication-Sign 10{sup 11} M{sub Sun }, and gas fractions of {approx}40%. Velocity dispersions are modest so the disks are unstable, potentially on scales commensurate with their radii: these galaxies are undergoing extreme bursts of star formation, not confined to their nuclei, at close to the Eddington limit. Their specific star formation rates place them {approx}> 5 Multiplication-Sign above the main sequence, which supposedly comprises large gas disks like these. Their high star formation efficiencies aremore » difficult to reconcile with a simple volumetric star formation law. N-body and dark matter simulations suggest that this system is the progenitor of a B(inary)-type Almost-Equal-To 10{sup 14.6}-M{sub Sun} cluster.« less
Authors:
 [1] ; ;  [2] ;  [3] ;  [4] ; ;  [5] ; ; ;  [6] ;  [7] ;  [8] ;  [9] ; ;  [10] ;  [11] ;  [12] ;  [13] ;  [14] ;  [15] more »; « less
  1. UK Astronomy Technology Centre, Science and Technology Facilities Council, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom)
  2. Institute for Computational Cosmology, Durham University, South Road, Durham DH1 3LE (United Kingdom)
  3. Department of Astronomy, University of Maryland, College Park, MD 20742 (United States)
  4. Harvard-Smithsonian Center for Astrophysics, 60 Garden St, Cambridge, MA 02138 (United States)
  5. Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States)
  6. Institut de Radioastronomie Millimetrique, 300 rue de la Piscine, F-38406 Saint-Martin d'Heres (France)
  7. Department of Astronomy, University of Minnesota, Minneapolis, MN 55414 (United States)
  8. Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States)
  9. INAF, Osservatorio Astronomico di Padova, I-35122 Padova (Italy)
  10. Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom)
  11. Centre de Recherche Astrophysique de Lyon, Universite Lyon 1, 9 Avenue Charles Andre, F-69561 Saint Genis Laval Cedex (France)
  12. Department of Astronomy, Space Science Building, Cornell University, Ithaca, NY 14853-6801 (United States)
  13. School of Physics and Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD (United Kingdom)
  14. The Henry A. Rowland Department of Physics and Astronomy, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218 (United States)
  15. Department of Physical Sciences, The Open University, Milton Keynes (United Kingdom)
Publication Date:
OSTI Identifier:
22121760
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 772; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BINARY STARS; COMPUTERIZED SIMULATION; COSMIC NUCLEI; GALAXIES; INFRARED RADIATION; LUMINOSITY; MANY-BODY PROBLEM; NONLUMINOUS MATTER; PROTOSTARS; RED SHIFT; STAR CLUSTERS