TY - JOUR
T1 - Active Galactic Nuclei and Host Galaxies in COSMOS-Web. II. First Look At the Kiloparsec-scale Dual and Offset AGN Population
AU - Li, Junyao
AU - Zhuang, Ming Yang
AU - Shen, Yue
AU - Volonteri, Marta
AU - Chen, Nianyi
AU - Matteo, Tiziana Di
N1 - We thank the referee for the valuable comments, which have helped improve the quality of the paper. We thank Stefano Marchesi for providing us with the X-ray spectral fitting catalog, and Mara Salvato for providing the probability distribution of photometric redshifts in S. Marchesi et al. (2016a) for comparison. We thank Yelti Rosas-Guevara for useful discussions about dual AGNs in the EAGLE simulation. Based on observations with the NASA/ESA/CSA James Webb Space Telescope, obtained from the Barbara A. Mikulski Archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-03127. Support for Program numbers JWST-GO-02057 and JWST-AR-03038 was provided through a grant from the STScI under NASA contract NAS5-03127.
We thank the referee for the valuable comments, which have helped improve the quality of the paper. We thank Stefano Marchesi for providing us with the X-ray spectral fitting catalog, and Mara Salvato for providing the probability distribution of photometric redshifts in S. Marchesi et al. () for comparison. We thank Yelti Rosas-Guevara for useful discussions about dual AGNs in the EAGLE simulation. Based on observations with the NASA/ESA/CSA James Webb Space Telescope, obtained from the Barbara A. Mikulski Archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-03127. Support for Program numbers JWST-GO-02057 and JWST-AR-03038 was provided through a grant from the STScI under NASA contract NAS5-03127.
PY - 2025/6/10
Y1 - 2025/6/10
N2 - Kiloparsec-scale dual and offset active galactic nuclei (AGNs) are signposts of accreting supermassive black holes (SMBHs) triggered during late-stage galaxy mergers, offering crucial insights into the coevolution of SMBHs and galaxies. However, robustly confirmed systems at high redshift (e.g., z > 1) are scarce and biased toward the most luminous and unobscured systems. In this study, we systematically search for kiloparsec-scale (projected separation <15 kpc) dual and offset AGNs around 571 moderate-luminosity, X-ray-selected AGNs, including the obscured population, utilizing deep Hubble Space Telescope Advanced Camera for Surveys/F814W and multiband JWST NIRCam imaging from the COSMOS-Web survey. We identify 59 dual and 30 offset AGN candidates in late-stage major mergers based on spatially resolved spectral energy distribution analyses. This translates to ∼28 and ∼10 bona fide dual and offset AGNs, using a probabilistic pair-counting scheme to minimize chance superpositions. Notably, the fraction of dual and offset AGNs among moderate-luminosity (Lbol ∼ 1043−1046 erg s−1) obscured AGNs is nearly 2 orders of magnitude higher than that of the most luminous, unobscured quasar pairs. We find tentative evidence for an increasing pair fraction among AGNs with redshift (from a few percent at z ∼ 0.5 to ∼ 22 . 9 − 17.7 + 27.5 % at z ∼ 4.5) and a higher occurrence rate of dual over offset AGNs. There is no pileup of dual/offset AGNs below ∼2kpc separations. These results generally align with predictions from the ASTRID and Horizon-AGN cosmological simulations, when matching sample selection criteria, implying a high probability of both black holes being active simultaneously in late-stage major mergers.
AB - Kiloparsec-scale dual and offset active galactic nuclei (AGNs) are signposts of accreting supermassive black holes (SMBHs) triggered during late-stage galaxy mergers, offering crucial insights into the coevolution of SMBHs and galaxies. However, robustly confirmed systems at high redshift (e.g., z > 1) are scarce and biased toward the most luminous and unobscured systems. In this study, we systematically search for kiloparsec-scale (projected separation <15 kpc) dual and offset AGNs around 571 moderate-luminosity, X-ray-selected AGNs, including the obscured population, utilizing deep Hubble Space Telescope Advanced Camera for Surveys/F814W and multiband JWST NIRCam imaging from the COSMOS-Web survey. We identify 59 dual and 30 offset AGN candidates in late-stage major mergers based on spatially resolved spectral energy distribution analyses. This translates to ∼28 and ∼10 bona fide dual and offset AGNs, using a probabilistic pair-counting scheme to minimize chance superpositions. Notably, the fraction of dual and offset AGNs among moderate-luminosity (Lbol ∼ 1043−1046 erg s−1) obscured AGNs is nearly 2 orders of magnitude higher than that of the most luminous, unobscured quasar pairs. We find tentative evidence for an increasing pair fraction among AGNs with redshift (from a few percent at z ∼ 0.5 to ∼ 22 . 9 − 17.7 + 27.5 % at z ∼ 4.5) and a higher occurrence rate of dual over offset AGNs. There is no pileup of dual/offset AGNs below ∼2kpc separations. These results generally align with predictions from the ASTRID and Horizon-AGN cosmological simulations, when matching sample selection criteria, implying a high probability of both black holes being active simultaneously in late-stage major mergers.
UR - https://www.scopus.com/pages/publications/105008121759
UR - https://www.scopus.com/pages/publications/105008121759#tab=citedBy
U2 - 10.3847/1538-4357/adbae2
DO - 10.3847/1538-4357/adbae2
M3 - Article
AN - SCOPUS:105008121759
SN - 0004-637X
VL - 986
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 1
M1 - 101
ER -