The Astrophysical Journal (Jan 2024)
Brightest Cluster Galaxy Formation in the z = 4.3 Protocluster SPT 2349-56: Discovery of a Radio-loud Active Galactic Nucleus
- Scott C. Chapman,
- Ryley Hill,
- Manuel Aravena,
- Melanie Archipley,
- Arif Babul,
- James Burgoyne,
- Rebecca E. A. Canning,
- Roger P. Deane,
- Carlos De Breuck,
- Anthony H. Gonzalez,
- Christopher C. Hayward,
- Seon Woo Kim,
- Matt Malkan,
- Dan P. Marrone,
- Vincent McIntyre,
- Eric Murphy,
- Emily Pass,
- Ryan W. Perry,
- Kedar A. Phadke,
- Douglas Rennehan,
- Cassie Reuter,
- Kaja M. Rotermund,
- Douglas Scott,
- Nick Seymour,
- Manuel Solimano,
- Justin Spilker,
- Anthony A. Stark,
- Nikolaus Sulzenauer,
- Nick Tothill,
- Joaquin D. Vieira,
- David Vizgan,
- George Wang,
- Axel Weiss
Affiliations
- Scott C. Chapman
- ORCiD
- Department of Physics and Atmospheric Science, Dalhousie University , Halifax, NS, B3H 4R2, Canada ; [email protected]; NRC Herzberg Astronomy and Astrophysics , 5071 West Saanich Road, Victoria, BC, V9E 2E7, Canada; Department of Physics and Astronomy, University of British Columbia , Vancouver, BC, V6T 1Z1, Canada; Eureka Scientific Inc , Oakland, CA 94602, USA
- Ryley Hill
- Department of Physics and Astronomy, University of British Columbia , Vancouver, BC, V6T 1Z1, Canada
- Manuel Aravena
- ORCiD
- Núcleo de Astronomia, Facultad de Ingenieria y Ciencias, Universidad Diego Portales , Av. Ejército 441, Santiago, Chile
- Melanie Archipley
- ORCiD
- Department of Astronomy, University of Illinois , 1002 West Green Street, Urbana, IL 61801, USA; Center for AstroPhysical Surveys, National Center for Supercomputing Applications , 1205 West Clark Street, Urbana, IL 61801, USA
- Arif Babul
- Department of Physics and Astronomy, University of Victoria , Victoria, BC, V8P 1A1, Canada
- James Burgoyne
- Department of Physics and Astronomy, University of British Columbia , Vancouver, BC, V6T 1Z1, Canada
- Rebecca E. A. Canning
- Institute of Cosmology and Gravitation, University of Portsmouth , Dennis Sciama Building, Portsmouth, PO1 3FX, UK
- Roger P. Deane
- Wits Centre for Astrophysics, School of Physics, University of the Witwatersrand , 1 Jan Smuts Avenue, Johannesburg, 2000, South Africa; Department of Physics, University of Pretoria , Private Bag X20, Pretoria 0028, South Africa
- Carlos De Breuck
- European Southern Observatory , Karl Schwarzschild Strasse 2, D-85748 Garching, Germany
- Anthony H. Gonzalez
- ORCiD
- Department of Astronomy, University of Florida , 211 Bryant Space Science Center, Gainesville, FL 32611-2055, USA
- Christopher C. Hayward
- ORCiD
- Center for Computational Astrophysics, Flatiron Institute , 162 Fifth Avenue, New York, NY 10010, USA
- Seon Woo Kim
- Department of Astronomy, University of Illinois , 1002 West Green Street, Urbana, IL 61801, USA
- Matt Malkan
- ORCiD
- Department of Physics and Astronomy, University of California, Los Angeles , CA 90095, USA
- Dan P. Marrone
- ORCiD
- Steward Observatory, University of Arizona , 933 North Cherry Avenue, Tucson, AZ 85721, USA
- Vincent McIntyre
- International Center for Radio Astronomy Research, Curtin University , GPO Box U1987, Perth, WA 6845, Australia
- Eric Murphy
- ORCiD
- NRAO National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903, USA
- Emily Pass
- ORCiD
- Department of Physics and Atmospheric Science, Dalhousie University , Halifax, NS, B3H 4R2, Canada ; [email protected]; Harvard-Smithsonian Center for Astrophysics , 60 Garden Street, Cambridge, MA 02138, USA
- Ryan W. Perry
- Department of Physics and Atmospheric Science, Dalhousie University , Halifax, NS, B3H 4R2, Canada ; [email protected]
- Kedar A. Phadke
- ORCiD
- Department of Astronomy, University of Illinois , 1002 West Green Street, Urbana, IL 61801, USA; Center for AstroPhysical Surveys, National Center for Supercomputing Applications , 1205 West Clark Street, Urbana, IL 61801, USA
- Douglas Rennehan
- Center for Computational Astrophysics, Flatiron Institute , 162 Fifth Avenue, New York, NY 10010, USA
- Cassie Reuter
- ORCiD
- Department of Astronomy, University of Illinois , 1002 West Green Street, Urbana, IL 61801, USA
- Kaja M. Rotermund
- ORCiD
- Lawrence Berkeley National Laboratory , Berkeley, CA 94720, USA
- Douglas Scott
- ORCiD
- Department of Physics and Astronomy, University of British Columbia , Vancouver, BC, V6T 1Z1, Canada
- Nick Seymour
- International Center for Radio Astronomy Research, Curtin University , GPO Box U1987, Perth, WA 6845, Australia
- Manuel Solimano
- ORCiD
- Núcleo de Astronomia, Facultad de Ingenieria y Ciencias, Universidad Diego Portales , Av. Ejército 441, Santiago, Chile
- Justin Spilker
- ORCiD
- Department of Physics and Astronomy and George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Texas A&M University , 4242 TAMU, College Station, TX 77843-4242, USA
- Anthony A. Stark
- ORCiD
- Harvard-Smithsonian Center for Astrophysics , 60 Garden Street, Cambridge, MA 02138, USA
- Nikolaus Sulzenauer
- ORCiD
- Max-Planck-Institut für Radioastronomie , Auf dem Hugel 69, Bonn, D-53121, Germany
- Nick Tothill
- ORCiD
- School of Science, Western Sydney University , Locked Bag 1797, Penrith, NSW 2751, Australia
- Joaquin D. Vieira
- ORCiD
- Department of Astronomy, University of Illinois , 1002 West Green Street, Urbana, IL 61801, USA; Center for AstroPhysical Surveys, National Center for Supercomputing Applications , 1205 West Clark Street, Urbana, IL 61801, USA
- David Vizgan
- ORCiD
- Department of Astronomy, University of Illinois , 1002 West Green Street, Urbana, IL 61801, USA
- George Wang
- Department of Physics and Astronomy, University of British Columbia , Vancouver, BC, V6T 1Z1, Canada
- Axel Weiss
- ORCiD
- Max-Planck-Institut für Radioastronomie , Auf dem Hugel 69, Bonn, D-53121, Germany
- DOI
- https://doi.org/10.3847/1538-4357/ad0b77
- Journal volume & issue
-
Vol. 961,
no. 1
p. 120
Abstract
We have observed the z = 4.3 protocluster SPT2349−56 with the Australia Telescope Compact Array (ATCA) with the aim of detecting radio-loud active galactic nuclei (AGNs) among the ∼30 submillimeter (submm) galaxies (SMGs) identified in the structure. We detect the central complex of submm sources at 2.2 GHz with a luminosity of L _2.2 = (4.42 ± 0.56) × 10 ^25 W Hz ^−1 . MeerKAT and the Australian Square Kilometre Array Pathfinder also detect the source at 816 MHz and 888 MHz, respectively, constraining the radio spectral index to α = −1.45 ± 0.16, implying L _1.4,rest = (2.2 ± 0.2) × 10 ^26 W Hz ^−1 . The radio observations do not have sufficient spatial resolution to uniquely identify one of the three Atacama Large Millimeter/submillimeter Array (ALMA) galaxies as the AGN, however the ALMA source properties themselves suggest a likely host. This radio luminosity is ∼100× higher than expected from star formation, assuming the usual far-infrared–radio correlation, indicating an AGN driven by a forming brightest cluster galaxy. None of the SMGs in SPT2349−56 show signs of AGNs in any other diagnostics available to us, highlighting the radio continuum as a powerful probe of obscured AGNs. We compare these results to field samples of radio sources and SMGs, along with the 22 gravitationally lensed SPT-SMGs also observed in the ATCA program, as well as powerful radio galaxies at high redshifts. The (3.3 ± 0.7) × 10 ^38 W of power from the radio-loud AGN sustained over 100 Myr is comparable to the binding energy of the gas mass of the central halo, and similar to the instantaneous energy injection from supernova feedback from the SMGs in the core region. The SPT2349−56 radio-loud AGNs may be providing strong feedback on a nascent intracluster medium.
Keywords
