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Title: THE ANATOMY OF AN EXTREME STARBURST WITHIN 1.3 Gyr OF THE BIG BANG REVEALED BY ALMA

We present further analysis of the [C II] 158 {mu}m fine structure line and thermal dust continuum emission from the archetype extreme starburst/active galactic nucleus (AGN) group of galaxies in the early universe, BRI 1202-0725 at z = 4.7, using the Atacama Large Millimeter Array. The group has long been noted for having a closely separated (26 kpc in projection) FIR-hyperluminous quasar host galaxy and an optically obscured submillimeter galaxy (SMG). A short ALMA test observation reveals a rich laboratory for the study of the myriad processes involved in clustered massive galaxy formation in the early universe. Strong [C II] emission from the SMG and the quasar have been reported earlier by Wagg et al. based on these observations. In this paper, we examine in more detail the imaging results from the ALMA observations, including velocity channel images, position-velocity plots, and line moment images. We present detections of [C II] emission from two Ly{alpha}-selected galaxies in the group, demonstrating the relative ease with which ALMA can detect the [C II] emission from lower star formation rate galaxies at high redshift. Imaging of the [C II] emission shows a clear velocity gradient across the SMG, possibly indicating rotation or a moremore » complex dynamical system on a scale {approx}10 kpc. There is evidence in the quasar spectrum and images for a possible outflow toward the southwest, as well as more extended emission (a {sup b}ridge{sup )}, between the quasar and the SMG, although the latter could simply be emission from Ly{alpha}-1 blending with that of the quasar at the limited spatial resolution of the current observations. These results provide an unprecedented view of a major merger of gas-rich galaxies driving extreme starbursts and AGN accretion during the formation of massive galaxies and supermassive black holes within 1.3 Gyr of the big bang.« less
Authors:
 [1] ;  [2] ;  [3] ; ;  [4] ;  [5] ;  [6] ;  [7]
  1. National Radio Astronomy Observatory, P.O. Box 0, Socorro, NM 87801 (United States)
  2. Astronomy Department, California Institute of Technology, MC 249-17, 1200 East California Boulevard, Pasadena, CA 91125 (United States)
  3. Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany)
  4. Astrophysics Group, Cavendish Laboratory, J. J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom)
  5. European Southern Observatory, Alonso de Cordova 3107, Vitacura, Casilla 19001, Santiago 19 (Chile)
  6. Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom)
  7. Department of Physics and Center for Astrophysics and Space Sciences, University of California, San Diego, La Jolla, CA 92093 (United States)
Publication Date:
OSTI Identifier:
22167118
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 763; 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; BLACK HOLES; DUSTS; EMISSION; FINE STRUCTURE; GALAXIES; IMAGES; NUCLEI; QUASARS; RED SHIFT; ROTATION; SPATIAL RESOLUTION; STAR EVOLUTION; STARS; UNIVERSE; VELOCITY