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arXiv · 2403.07717

Resolving Dual Active Galactic Nuclei with ~100 pc separation in MCG-03-34-64

Anna Trindade Falcao·T. J. Turner·S. B. Kraemer·V. Braito·J. Reeves·H. R. Schmitt·L. Feuillet
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Abstract

We report the serendipitous multiwavelength discovery of a candidate dual black hole system with a separation of ~100 pc, in the gas-rich luminous infrared galaxy MCG-03-34-64 (z=0.016). Hubble Space Telescope/ACS observations show three distinct optical centroids in the [O III] narrow-band and F814W images. Subsequent analysis of Chandra/ACIS data shows two spatially-resolved peaks of equal intensity in the neutral Fe Ka (6.2-6.6 keV) band, while high-resolution radio continuum observations with the Very Large Array at 8.46 GHz (3.6 cm band) show two spatially-coincident radio peaks. Fast shocks as the ionizing source seem unlikely, given the energies required for production of Fe Ka. If confirmed, the separation of ~100 pc would represent the closest dual AGN reported to date with spatially-resolved, multiwavelength observations.

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Anna Trindade Falcao, T. J. Turner, S. B. Kraemer, V. Braito, J. Reeves, H. R. Schmitt, L. Feuillet. 2024-03-12. Resolving Dual Active Galactic Nuclei with ~100 pc separation in MCG-03-34-64. https://arxiv.org/abs/2403.07717

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