The Astrophysical Journal Letters (Jan 2023)
UGC 4211: A Confirmed Dual Active Galactic Nucleus in the Local Universe at 230 pc Nuclear Separation
- Michael J. Koss,
- Ezequiel Treister,
- Darshan Kakkad,
- J. Andrew Casey-Clyde,
- Taiki Kawamuro,
- Jonathan Williams,
- Adi Foord,
- Benny Trakhtenbrot,
- Franz E. Bauer,
- George C. Privon,
- Claudio Ricci,
- Richard Mushotzky,
- Loreto Barcos-Munoz,
- Laura Blecha,
- Thomas Connor,
- Fiona Harrison,
- Tingting Liu,
- Macon Magno,
- Chiara M. F. Mingarelli,
- Francisco Muller-Sanchez,
- Kyuseok Oh,
- T. Taro Shimizu,
- Krista Lynne Smith,
- Daniel Stern,
- Miguel Parra Tello,
- C. Megan Urry
Affiliations
- Michael J. Koss
- ORCiD
- Eureka Scientific, 2452 Delmer Street Suite 100, Oakland, CA 94602-3017, USA ; [email protected]
- Ezequiel Treister
- ORCiD
- Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile , Campus San Joaquín, Av. Vicuña Mackenna 4860, Macul Santiago, 7820436, Chile
- Darshan Kakkad
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- J. Andrew Casey-Clyde
- ORCiD
- Department of Physics, University of Connecticut , 196 Auditorium Road, U-3046, Storrs, CT 06269-3046, USA; Center for Computational Astrophysics, Flatiron Institute , 162 Fifth Avenue, New York, NY 10010, USA
- Taiki Kawamuro
- ORCiD
- RIKEN Cluster for Pioneering Research , 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- Jonathan Williams
- ORCiD
- Department of Astronomy, University of Maryland , College Park, MD 20742, USA
- Adi Foord
- ORCiD
- Kavli Institute of Particle Astrophysics and Cosmology, Stanford University , Stanford, CA 94305, USA
- Benny Trakhtenbrot
- ORCiD
- School of Physics and Astronomy, Tel Aviv University , Tel Aviv 69978, Israel
- Franz E. Bauer
- ORCiD
- Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile , Campus San Joaquín, Av. Vicuña Mackenna 4860, Macul Santiago, 7820436, Chile; Centro de Astroingeniería, Facultad de Física, Pontificia Universidad Católica de Chile , Campus San Joaquín, Av. Vicuña Mackenna 4860, Macul Santiago, 7820436, Chile; Millennium Institute of Astrophysics , Nuncio Monseñor Sótero Sanz 100, Of 104, Providencia, Santiago, Chile; Space Science Institute , 4750 Walnut Street, Suite 205, Boulder, Colorado 80301, USA
- George C. Privon
- ORCiD
- National Radio Astronomy Observatory , 520 Edgemont Road, Charlottesville, VA 22903, USA; Department of Astronomy, University of Florida , P.O. Box 112055, Gainesville, FL 32611, USA
- Claudio Ricci
- ORCiD
- Núcleo de Astronomía de la Facultad de Ingeniería, Universidad Diego Portales , Av. Ejército Libertador 441, Santiago 22, Chile; Kavli Institute for Astronomy and Astrophysics, Peking University , Beijing 100871, People’s Republic of China
- Richard Mushotzky
- ORCiD
- Department of Astronomy, University of Maryland , College Park, MD 20742, USA; Joint Space-Science Institute, University of Maryland , College Park, MD 20742, USA
- Loreto Barcos-Munoz
- ORCiD
- National Radio Astronomy Observatory , 520 Edgemont Road, Charlottesville, VA 22903, USA
- Laura Blecha
- ORCiD
- University of Florida , Department of Physics, 2001 Museum Road, Gainesville, FL 32611, USA
- Thomas Connor
- ORCiD
- Jet Propulsion Laboratory, California Institute of Technology , 4800 Oak Grove Drive, Pasadena, CA 91109, USA
- Fiona Harrison
- Cahill Center for Astronomy and Astrophysics, California Institute of Technology , Pasadena, CA 91125, USA
- Tingting Liu
- ORCiD
- Center for Gravitation, Cosmology and Astrophysics, Department of Physics, University of Wisconsin-Milwaukee , Milwaukee, WI 53211, USA
- Macon Magno
- ORCiD
- Department of Physics, Southern Methodist University , Dallas, TX 75205, USA
- Chiara M. F. Mingarelli
- ORCiD
- Department of Physics, University of Connecticut , 196 Auditorium Road, U-3046, Storrs, CT 06269-3046, USA; Center for Computational Astrophysics, Flatiron Institute , 162 Fifth Avenue, New York, NY 10010, USA
- Francisco Muller-Sanchez
- ORCiD
- Department of Physics and Materials Science, The University of Memphis , 3720 Alumni Avenue, Memphis, TN 38152, USA
- Kyuseok Oh
- ORCiD
- Korea Astronomy & Space Science institute , 776, Daedeokdae-ro, Yuseong-gu, Daejeon 34055, Republic of Korea; Department of Astronomy, Kyoto University , Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
- T. Taro Shimizu
- ORCiD
- Max-Planck-Institut für extraterrestrische Physik (MPE) , Giessenbachstrasse 1, D-85748 Garching bei Müunchen, Germany
- Krista Lynne Smith
- ORCiD
- Department of Physics, Southern Methodist University , Dallas, TX 75205, USA
- Daniel Stern
- ORCiD
- Jet Propulsion Laboratory, California Institute of Technology , 4800 Oak Grove Drive, MS 169-224, Pasadena, CA 91109, USA
- Miguel Parra Tello
- ORCiD
- Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile , Campus San Joaquín, Av. Vicuña Mackenna 4860, Macul Santiago, 7820436, Chile
- C. Megan Urry
- ORCiD
- Yale Center for Astronomy & Astrophysics and Department of Physics, Yale University , P.O. Box 208120, New Haven, CT 06520-8120, USA
- DOI
- https://doi.org/10.3847/2041-8213/aca8f0
- Journal volume & issue
-
Vol. 942,
no. 1
p. L24
Abstract
We present multiwavelength high-spatial resolution (∼0.″1, 70 pc) observations of UGC 4211 at z = 0.03474, a late-stage major galaxy merger at the closest nuclear separation yet found in near-IR imaging (0.″32, ∼230 pc projected separation). Using Hubble Space Telescope/Space Telescope Imaging Spectrograph, Very Large Telescope/MUSE+AO, Keck/OSIRIS+AO spectroscopy, and the Atacama Large Millimeter/submillimeter Array (ALMA) observations, we show that the spatial distribution, optical and near-infrared emission lines, and millimeter continuum emission are all consistent with both nuclei being powered by accreting supermassive black holes (SMBHs). Our data, combined with common black hole mass prescriptions, suggest that both SMBHs have similar masses, $\mathrm{log}\left({M}_{\mathrm{BH}}/{M}_{\odot }\right)$ ∼ 8.1 (south) and $\mathrm{log}\left({M}_{\mathrm{BH}}/{M}_{\odot }\right)$ ∼ 8.3 (north), respectively. The projected separation of 230 pc (∼6× the black hole sphere of influence) represents the closest-separation dual active galactic nuclei (AGN) studied to date with multiwavelength resolved spectroscopy and shows the potential of nuclear (<50 pc) continuum observations with ALMA to discover hidden growing SMBH pairs. While the exact occurrence rate of close-separation dual AGN is not yet known, it may be surprisingly high, given that UGC 4211 was found within a small, volume-limited sample of nearby hard X-ray detected AGN. Observations of dual SMBH binaries in the subkiloparsec regime at the final stages of dynamical friction provide important constraints for future gravitational wave observatories.
Keywords
- AGN host galaxies
- X-ray active galactic nuclei
- Galaxy mergers
- Interacting galaxies
- Galaxy collisions
- AB photometry
