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arXiv · 1907.10161

Dual black hole associated with obscured and unobscured AGN: CXO J101527.2+625911

D. -C. Kim·E. Momjian·Ilsang Yoon·Minjin Kim·A. S. Evans·Ji Hoon Kim·S. T. Linden·L. Barcos-Munoz·G. C. Privon
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Abstract

We report the results of an investigation to determine the nature of the offset active galactic nucleus (AGN) found in the source CXO J101527.2+625911. Hubble Space Telescope and Chandra X-ray observatory data had suggested that the offset AGN, which has an angular separation of only 0\farcs26 from the center of the host galaxy, is a recoiled Super Massive Black Hole (rSMBH). We carried out high angular resolution observations with both the VLBA (1.54 GHz) and the VLA (10.0 GHz \& 33.0 GHz) and detected a single compact radio source in the center of the host galaxy, with no radio continuum emission associated with the offset AGN. The detected radio source has a high brightness temperature value of $T_b=7.2\times10^{7}$ K, indicating that the radio emission is associated with an AGN. Furthermore, we present the decomposition of high-resolution KECK spectra of the [O III]5007\AA line into two narrow emission line components, which is a characteristic sign of a dual black hole system. These new radio and optical wavelength results suggest that CXO J101527.2+625911 is the host of a dual black hole system rather than a rSMBH.

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D. -C. Kim, E. Momjian, Ilsang Yoon, Minjin Kim, A. S. Evans, Ji Hoon Kim, S. T. Linden, L. Barcos-Munoz, G. C. Privon. 2019-07-23. Dual black hole associated with obscured and unobscured AGN: CXO J101527.2+625911. https://doi.org/10.3847/1538-4357%2Fab2e0b

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