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arXiv · 2601.20984

Radio-Near Infrared Imaging of Dual Active Galactic Nuclei Candidates

Makoto A. Johnstone·Ilsang Yoon·Emmanuel Momjian·Loreto Barcos-Muñoz·A. S. Evans·Bjorn Emonts·Eilat Glikman·Dong-Chan Kim·Ji Hoon Kim·Minjin Kim·Mark Lacy·George C. Privon·Devaky Kunneriath·Jaya Nagarajan-Swenson·Núria Torres-Albà·Kara N. Green
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Abstract

We report the results of a pilot study that searched for dual active galactic nuclei (AGN) in local ($z<$0.25) galaxies hosting double-peaked narrow emission lines in their optical spectra. We present high-resolution $L-$band (1.5 GHz or 18 cm) continuum images from the Very Long Baseline Array (VLBA) as well as WFC3/IR F160W images from the Hubble Space Telescope of two candidate dual AGN systems: J0948+6848 and J1223+5409. In both targets, we detected compact non-thermal radio emission that is approximately co-spatial with the near-infrared AGN. Both systems host two high brightness temperature ($>10^{8}$ K) radio sources that indicate the presence of either a parsec-scale-separation dual AGN ($d_{\text{sep}} \sim 90$ pc and $\sim 56$ pc, respectively) or a radio jet. Matched-resolution multi-band radio observations are necessary to further characterize the AGN activity in these systems.

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Makoto A. Johnstone, Ilsang Yoon, Emmanuel Momjian, Loreto Barcos-Muñoz, A. S. Evans, Bjorn Emonts, Eilat Glikman, Dong-Chan Kim, Ji Hoon Kim, Minjin Kim, Mark Lacy, George C. Privon, Devaky Kunneriath, Jaya Nagarajan-Swenson, Núria Torres-Albà, Kara N. Green. 2026-01-28. Radio-Near Infrared Imaging of Dual Active Galactic Nuclei Candidates. https://arxiv.org/abs/2601.20984

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