Cospatial Star Formation and Supermassive Black Hole Growth in z ~ 3 Galaxies: Evidence for In Situ Co-evolution

Scientific paper - Original scientific paper

• Author: W. Rujopakarn
• Author: K. Nyland
• Author: G. H. Rieke
• Author: G. Barro
• Author: D. Elbaz
• Author: R. J. Ivison
• Author: P. Jagannathan
• Author: J. D. Silverman
• Author: Vernesa Smolčić
• Author: T. Wang
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics; Astronomy and Astrophysics

Abstract (english)

We present a sub-kiloparsec localization of the sites of supermassive black hole (SMBH) growth in three active galactic nuclei (AGNs) at z ~ 3 in relation to the regions of intense star formation in their hosts. These AGNs are selected from Karl G. Jansky Very Large Array (VLA) and Atacama Large Millimeter/submillimeter Array (ALMA) observations in the Hubble Ultra-Deep Field and COSMOS, with the centimetric radio emission tracing both star formation and AGN, and the sub/millimeter emission by dust tracing nearly pure star formation. We require radio emission to be $\geqslant 5\times $ more luminous than the level associated with the sub/millimeter star formation to ensure that the radio emission is AGN-dominated, thereby allowing localization of the AGN and star formation independently. In all three galaxies, the AGNs are located within the compact regions of gas- rich, heavily obscured, intense nuclear star formation, with R e = 0.4–1.1 kpc and average star formation rates of sime100–1200 M ⊙ yr−1. If the current episode of star formation continues at such a rate over the stellar mass doubling time of their hosts, sime0.2 Gyr, the newly formed stellar mass will be of the order of 1011 M ⊙ within the central kiloparsec region, concurrently and cospatially with significant growth of the SMBH. This is consistent with a picture of in situ galactic bulge and SMBH formation. This work demonstrates the unique complementarity of VLA and ALMA observations to unambiguously pinpoint the locations of AGNs and star formation down to sime30 mas, corresponding to sime230 pc at z = 3.

• Keywords (english): galaxies: evolution; galaxies: starburst
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Astrophysical Journal Letters
• Numbering: vol. 854, no. 1, L4
• p-ISSN: 2041-8205
• DOI: https://doi.org/10.3847/2041-8213/aaa9b3
• URN:NBN: urn:nbn:hr:217:485433
• Publication: 2018
• Document URL: https://iopscience.iop.org/article/10.3847/2041-8213/aaa9b3
• Type of resource: Text
• Access conditions: Open access
• Public note: © 2018. The American Astronomical Society. Received 2017 December 7; accepted 2018 January 21; published 2018 February 7.
• Created on: 2020-03-01 16:38:58