Galaxy growth in a massive halo in the first billion years of cosmic history.

Autor: Marrone DP; Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, Arizona 85721, USA., Spilker JS; Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, Arizona 85721, USA., Hayward CC; Center for Computational Astrophysics, Flatiron Institute, 162 Fifth Avenue, New York, New York 10010, USA.; Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA., Vieira JD; Department of Astronomy, University of Illinois, 1002 West Green Street, Urbana, Illinois 61801, USA., Aravena M; Núcleo de Astronomía, Facultad de Ingeniería, Universidad Diego Portales, Avenida Ejército 441, Santiago, Chile., Ashby MLN; Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA., Bayliss MB; Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA., Béthermin M; Aix Marseille Université, CNRS, LAM, Laboratoire d'Astrophysique de Marseille, Marseille, France., Brodwin M; Department of Physics and Astronomy, University of Missouri, 5110 Rockhill Road, Kansas City, Missouri 64110, USA., Bothwell MS; Cavendish Laboratory, University of Cambridge, 19 J. J. Thomson Avenue, Cambridge CB3 0HE, UK.; Kavli Institute for Cosmology, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK., Carlstrom JE; Kavli Institute for Cosmological Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637, USA.; Department of Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637, USA.; Enrico Fermi Institute, University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637, USA.; Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637, USA., Chapman SC; Dalhousie University, Halifax, Nova Scotia, Canada., Chen CC; European Southern Observatory, Karl Schwarzschild Straße 2, 85748 Garching, Germany., Crawford TM; Kavli Institute for Cosmological Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637, USA.; Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637, USA., Cunningham DJM; Dalhousie University, Halifax, Nova Scotia, Canada.; Department of Astronomy and Physics, Saint Mary's University, Halifax, Nova Scotia, Canada., De Breuck C; European Southern Observatory, Karl Schwarzschild Straße 2, 85748 Garching, Germany., Fassnacht CD; Department of Physics, University of California, One Shields Avenue, Davis, California 95616, USA., Gonzalez AH; Department of Astronomy, University of Florida, Bryant Space Sciences Center, Gainesville, Florida 32611 USA., Greve TR; Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK., Hezaveh YD; Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, California 94305, USA., Lacaille K; Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada., Litke KC; Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, Arizona 85721, USA., Lower S; Department of Astronomy, University of Illinois, 1002 West Green Street, Urbana, Illinois 61801, USA., Ma J; Department of Astronomy, University of Florida, Bryant Space Sciences Center, Gainesville, Florida 32611 USA., Malkan M; Department of Physics and Astronomy, University of California, Los Angeles, California 90095-1547, USA., Miller TB; Dalhousie University, Halifax, Nova Scotia, Canada., Morningstar WR; Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, California 94305, USA., Murphy EJ; National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, Virginia 22903, USA., Narayanan D; Department of Astronomy, University of Florida, Bryant Space Sciences Center, Gainesville, Florida 32611 USA., Phadke KA; Department of Astronomy, University of Illinois, 1002 West Green Street, Urbana, Illinois 61801, USA., Rotermund KM; Dalhousie University, Halifax, Nova Scotia, Canada., Sreevani J; Department of Astronomy, University of Illinois, 1002 West Green Street, Urbana, Illinois 61801, USA., Stalder B; Large Synoptic Survey Telescope, 950 North Cherry Avenue, Tucson, Arizona 85719, USA., Stark AA; Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA., Strandet ML; Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, Germany.; International Max Planck Research School (IMPRS) for Astronomy and Astrophysics, Universities of Bonn and Cologne, Bonn, Germany., Tang M; Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, Arizona 85721, USA., Weiß A; Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, Germany.
Jazyk: angličtina
Zdroj: Nature [Nature] 2018 Jan 04; Vol. 553 (7686), pp. 51-54. Date of Electronic Publication: 2017 Dec 06.
DOI: 10.1038/nature24629
Abstrakt: According to the current understanding of cosmic structure formation, the precursors of the most massive structures in the Universe began to form shortly after the Big Bang, in regions corresponding to the largest fluctuations in the cosmic density field. Observing these structures during their period of active growth and assembly-the first few hundred million years of the Universe-is challenging because it requires surveys that are sensitive enough to detect the distant galaxies that act as signposts for these structures and wide enough to capture the rarest objects. As a result, very few such objects have been detected so far. Here we report observations of a far-infrared-luminous object at redshift 6.900 (less than 800 million years after the Big Bang) that was discovered in a wide-field survey. High-resolution imaging shows it to be a pair of extremely massive star-forming galaxies. The larger is forming stars at a rate of 2,900 solar masses per year, contains 270 billion solar masses of gas and 2.5 billion solar masses of dust, and is more massive than any other known object at a redshift of more than 6. Its rapid star formation is probably triggered by its companion galaxy at a projected separation of 8 kiloparsecs. This merging companion hosts 35 billion solar masses of stars and has a star-formation rate of 540 solar masses per year, but has an order of magnitude less gas and dust than its neighbour and physical conditions akin to those observed in lower-metallicity galaxies in the nearby Universe. These objects suggest the presence of a dark-matter halo with a mass of more than 100 billion solar masses, making it among the rarest dark-matter haloes that should exist in the Universe at this epoch.
Databáze: MEDLINE