The multiple merger assembly of a hyperluminous obscured quasar at redshift 4.6
Galaxy mergers and gas accretion from the cosmic web drove the growth of galaxies and their central black holes at early epochs. We report spectroscopic imaging of a multiple merger event in the most luminous known galaxy, WISE J224607.56−052634.9 (W2246−0526), a dust-obscured quasar at redshift 4.6, 1.3 billion years after the Big Bang. Far-infrared dust continuum observations show three galaxy companions around W2246−0526 with disturbed morphologies, connected by streams of dust likely produced by the dynamical interaction. The detection of tidal dusty bridges shows that W2246−0526 is accreting its neighbors, suggesting that merger activity may be a dominant mechanism through which the most luminous galaxies simultaneously obscure and feed their central supermassive black holes.
Additional Information© 2018 American Association for the Advancement of Science. 9 November 2017; accepted 26 October 2018. Published online 15 November 2018. We thank A. Stanford and M. Baloković for helping to obtain optical spectra for W2246−0526 on November 2010 and October 2013, respectively. We thank J. González López for helpful suggestions regarding the cleaning algorithms of CASA. ALMA is a partnership of the European Southern Observatory (ESO) (representing its member states), NSF (United States), and the National Institute of Natural Sciences (Japan), together with the National Research Council (Canada) and National Science Council and Academia Sinica's Institute of Astronomy and Astrophysics (Taiwan), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, Associated Universities Inc. (AUI)/National Radio Astronomy Observatory (NRAO) and National Astronomical Observatory of Japan. The NRAO is a facility of NSF operated under cooperative agreement by AUI. This work is also based in part on archival observations from the Spitzer Space Telescope, the Herschel Space Observatory, WISE, as well as from the NASA/European Space agency HST. Some of the data were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and NASA. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. T.D.-S. acknowledges support from ALMA-CONYCIT project 31130005 and Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT) project 1151239. R.J.A. acknowledges support from FONDECYT 1151408. The work of C-W.T., J.W., P.E., and D.S. was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA, and supported by grant ADAP13-0092. M.A. acknowledges partial support from FONDECYT through grant 1140099. J.W. acknowledges support from the Ministry of Science and Technology of China through grant 2016YFA0400702 and National Natural Science Foundation of China 11673029. This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2017R1A6A3A04005158). Author contributions: T.D.-S. lead the overall project. R.J.A. and A.W.B. contributed to the interpretation of the results. M.A. helped with processing the ALMA and VLA data. D.S. led the spectroscopic identification campaign of hot DOGs. C.-W.T., P.E., and J.W. contributed to the discussion of the results. K.D., H.I, G.L., and F.L. were part of the team that acquired the optical spectra of W2246−0526. Data and materials availability: The ALMA observations are available at http://almascience.nrao.edu/aq under project 2015.1.00883.S (principal investigator, T.D.-S.). The VLA observations can be retrieved from https://science.nrao.edu/facilities/vla/archive/index under project 15B-192 (principal investigator, R.J.A.). The Spitzer data can be retrieved from the Spitzer Heritage Archive (SHA) at http://sha.ipac.caltech.edu/applications/Spitzer/SHA under project 70162 (principal investigator, P.E.). The Herschel data are available at the Herschel Science Archive (HSA) http://archives.esac.esa.int/hsa/whsa under project OT1_peisenha_1 (principal investigator, P.E.). The WISE data can be accessed at http://wise2.ipac.caltech.edu/docs/release/allwise with documentation at http://wise2.ipac.caltech.edu/docs/release/allwise/expsup. The HST data are available at https://archive.stsci.edu/hst/search.php under project 12930 (principal investigator, C. Bridge). The Keck data are available in the Keck Observatory Archive at https://koa.ipac.caltech.edu by searching with the observation dates (15). The authors declare that there are no competing interests.
Accepted Version - 1811.05992
Supplemental Material - aap7605-Diaz-Santos-SM.pdf