Discovery of a Low-redshift Hot Dust-obscured Galaxy
We report the discovery of the hyperluminous, highly obscured active galactic nuclei (AGN) WISE J190445.04+485308.9 (W1904+4853, hereafter, L bol ∼ 1.1 × 1013 L ⊙) at z = 0.415. Its well-sampled spectral energy distribution (SED) is dominated by infrared dust emission, though broad emission lines are detected in the optical spectra. These features suggest that W1904+4853 contains an actively accreting supermassive black hole hidden in its dusty cocoon, resembling the observed properties of hot dust-obscured galaxies (Hot DOGs), a population previously only identified at z > 1.0. Using the broad component of the Mg ii 2798 Å emission line, we estimate a black hole mass of log ( M BH / M ⊙ ) = 8.4 ± 0.4 . The corresponding Eddington ratio (η) of 1.4 − 0.7 + 1.3 implies that the central black hole accretion is at the theoretical limit of isotropic accretion. The rest-frame UV-optical SED also indicates that the host galaxy of W1904+4853 harbors strong star formation activity at the rate of 6-84 M ⊙ yr−1 with an independent estimate of star formation rate up to ∼45 M ⊙ yr−1 using the [O ii] emission line. With an estimated stellar mass of 3 × 1010 M ⊙, the host galaxy appears to be a starburst system with respect to the main sequence of the star-forming galaxies at the same redshift. Although blueshifted and asymmetric [O iii] emission provides evidence of an outflow, we estimate it to be an order of magnitude smaller than the star formation rate, indicating that the current obscured AGN activity at the center has not yet produced significant feedback on the host galaxy star formation activity. W1904+4853 supports the interpretation that Hot DOGs are a rare transitional phase of AGN accretion in galaxy evolution, a phase that can persist into the present-day Universe.
Funding
National Natural Science Foundation of China (Nos. 11973051, 11673029)
International Partnership Program of the Chinese Academy of Sciences, program No. 114A11KYSB20210010
FONDECYT grant Nos. 1191124 and 1231718
Ministry of Science and ICT (MSIT) (Nos. 2020R1A2C3011091, 2021M3F7A1084525, 2022R1C1C2013543
NSFC grant No. U1931110
Chinese Academy of Sciences Presidents International Fellowship Initiative (No. 2019PM0017)
History
Citation
Guodong Li et al 2023 ApJ 958 162Author affiliation
Physics & AstronomyVersion
- VoR (Version of Record)
Published in
Astrophysical JournalVolume
958Issue
2Publisher
American Astronomical Societyissn
0004-637Xeissn
1538-4357Acceptance date
2023-06-26Copyright date
2023Available date
2024-03-01Publisher DOI
Language
enPublisher version
Deposited by
Professor Andrew BlainDeposit date
2024-02-12Rights Retention Statement
- No