Volume 661, May 2022
|Number of page(s)||8|
|Section||Letters to the Editor|
|Published online||10 May 2022|
Letter to the Editor
NOEMA observations support a recoiling black hole in 3C 186
Dipartimento di Fisica e Astronomia “Augusto Righi”, Alma Mater Studiorum Università di Bologna, Via Gobetti 93/2, 40129 Bologna, Italy
2 INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, Via Gobetti 93/3, 40129 Bologna, Italy
3 University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA
4 Space Telescope Science Institute for the European Space Agency (ESA), ESA Office, 3700 San Martin Drive, Baltimore, MD 21218, USA
5 The William H. Miller III Department of Physics & Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA
6 Observatoire de Paris, PSL University, Sorbonne University, CNRS, LERMA, 75014 Paris, France
7 Collège de France, 11 Place Marcelin Berthelot, 75231 Paris, France
8 Infrared Processing and Analysis Center, California Institute of Technology, MC 314-6, 1200 E. California Boulevard, Pasadena, CA 91125, USA
9 INAF – Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, Italy
10 Università degli Studi di Milano-Bicocca, Piazza della Scienza 3, 30126 Milano, Italy
11 INFN, Sezione di Milano-Bicocca, Piazza della Scienza 3, 30126 Milano, Italy
12 Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA
13 Space Telescope Science Institute, 3700 San Martin Dr., Baltimore, MD 21210, USA
Accepted: 12 April 2022
3C 186 is a powerful radio-loud quasar (a quasi-stellar object) at the center of a cool-core cluster at z = 1.06. Previous studies have reported evidence for a projected spatial offset of ∼1″ between the isophotal center of the galaxy and the point-source quasi-stellar object (QSO) as well as a spectral shift of ∼2000 km s−1 between the narrow and broad line region of the system. In this work we report high-resolution molecular gas CO(4→3) observations of the system taken with the NOEMA interferometer. We clearly detect a large reservoir of molecular gas, MH2 ∼ 8 × 1010 M⊙, that is co-spatial with the host galaxy and likely associated with a rotating disk-like structure. We firmly confirm both the spatial offset of the galaxy’s gas reservoir with respect to the continuum emission of the QSO and the spectral offset with respect to the redshift of the broad line region. Our morphological and kinematical analysis confirms that the most likely scenario to explain the 3C 186 system is that the QSO is a kicked super-massive black hole (SMBH), which we believe may have resulted from a strong gravitational wave recoil as two SMBHs coalesced after the merger of their host galaxies.
Key words: galaxies: active / quasars: individual: 3C186 / galaxies: jets / gravitational waves / galaxies: ISM / galaxies: star formation
© G. Castignani et al. 2022
Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.