A Caltech Library Service

CO-Dark Star Formation and Black Hole Activity in 3C 368 at z = 1.131: Coeval Growth of Stellar and Supermassive Black Hole Masses

Lamarche, C. and Stacey, G. and Brisbin, D. and Ferkinhoff, C. and Hailey-Dunsheath, S. and Nikola, T. and Riechers, D. and Sharon, C. E. and Spoon, H. and Vishwas, A. (2017) CO-Dark Star Formation and Black Hole Activity in 3C 368 at z = 1.131: Coeval Growth of Stellar and Supermassive Black Hole Masses. Astrophysical Journal, 836 (1). Art. No. 123. ISSN 0004-637X. doi:10.3847/1538-4357/836/1/123.

[img] PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


We present the detection of four far-infrared fine-structure oxygen lines, as well as strong upper limits for the CO(2–1) and [N ii] 205 μm lines, in 3C 368, a well-studied radio-loud galaxy at z = 1.131. These new oxygen lines, taken in conjunction with previously observed neon and carbon fine-structure lines, suggest a powerful active galactic nucleus (AGN), accompanied by vigorous and extended star formation. A starburst dominated by O8 stars, with an age of ~6.5 Myr, provides a good fit to the fine-structure line data. This estimated age of the starburst makes it nearly concurrent with the latest episode of AGN activity, suggesting a link between the growth of the supermassive black hole and stellar population in this source. We do not detect the CO(2–1) line, down to a level twelve times lower than the expected value for star-forming galaxies. This lack of CO line emission is consistent with recent star formation activity if the star-forming molecular gas has low metallicity, is highly fractionated (such that CO is photodissociated throughout much of the clouds), or is chemically very young (such that CO has not yet had time to form). It is also possible, although we argue it is unlikely, that the ensemble of fine-structure lines is emitted from the region heated by the AGN.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Brisbin, D.0000-0002-4795-419X
Hailey-Dunsheath, S.0000-0002-8504-7988
Riechers, D.0000-0001-9585-1462
Sharon, C. E.0000-0002-6250-5608
Spoon, H.0000-0002-8712-369X
Additional Information:© 2017. The American Astronomical Society. Received 2016 November 1; revised 2016 December 20; accepted 2017 January 9; published 2017 February 13. We thank the anonymous referee for the insightful comments and suggestions that helped to improve this manuscript. We additionally thank T. K. Daisy Leung and A. Gowardhan for help with preparing this manuscript in LaTeX. ZEUS observations were supported by NSF grant AST-01109476. C.L. acknowledges support from an NRAO Student Support Award, SOSPA3-011, and a New York Space Grant Award. D.B. acknowledges partial support from ALMA-CONICYT FUND No. 31140010. D.R. acknowledges support from the National Science Foundation under grant number AST-1614213 to Cornell University. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2012.1.00426.S and ADS/JAO.ALMA#2013.1.01223.S. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada) and NSC and ASIAA (Taiwan) and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. This work is based in part on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA.
Group:Infrared Processing and Analysis Center (IPAC)
Funding AgencyGrant Number
National Radio Astronomy ObservatorySOSPA3-011
New York Space Grant ConsortiumUNSPECIFIED
Comisión Nacional de Investigación Científica y Tecnológica (CONICYT)31140010
Subject Keywords:galaxies: evolution; galaxies: high-redshift; galaxies: ISM; galaxies: star formation; HII regions; photon-dominated region (PDR)
Issue or Number:1
Record Number:CaltechAUTHORS:20170213-154850887
Persistent URL:
Official Citation:C. Lamarche et al 2017 ApJ 836 123
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:74272
Deposited By: George Porter
Deposited On:14 Feb 2017 00:08
Last Modified:11 Nov 2021 05:25

Repository Staff Only: item control page