2018/01/22 by W. Rujopakarn, K. Nyland, G. H. Rieke +8 · 9 citations
Physics and Astronomy · #Active galactic nucleus #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Bulge #Galaxies: Formation, Evolution, Phenomena #Intergalactic star #Jansky #Quasar #Star formation #Supermassive black hole #astro-ph.CO #astro-ph.GA
paper · pdf · doi:10.3847/2041-8213/aaa9b3
published in The Astrophysical Journal Letters 854(1), L4 (IOP Publishing) · 7 pages, 3 figures, 2 tables. Accepted for publication in the Astrophysical Journal Letters
arxiv created 2018/01/22 · openalex created_date 2018/02/02 · openalex publication_date 2018/02/07 · arxiv updated 2018/02/21 · openalex updated_date 2026/08/05
Abstract 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 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 ≃100–1200 M ⊙ yr −1 . If the current episode of star formation continues at such a rate over the stellar mass doubling time of their hosts, ≃0.2 Gyr, the newly formed stellar mass will be of the order of 10 11 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 ≃30 mas, corresponding to ≃230 pc at z = 3.