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arXiv · 1711.06655

A possible binary AGN in Mrk\,622?

E. Benítez·J. M. Rodríguez-Espinosa·I. Cruz-González·O. González-Martín·C. A. Negrete·D. Ruschel-Dutra·L. Gutiérrez·E. Jiménez-Bailón
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Abstract

Mrk\,622 is a Compton Thick AGN and a double-peaked narrow emission line galaxy, thus a dual AGN candidate. In this work, new optical long-slit spectroscopic observations clearly show that this object is rather a triple peaked narrow emission line galaxy, with both blue and red shifted narrow emission lines, as well as a much narrower emission line centred at the host galaxy systemic velocity. The average velocity offset between the blue and red shifted components is $\sim$500 km\,s$^{-1}$, which is producing the apparent double-peaked emission lines. These two components are in the loci of AGN in the Baldwin, Phillips \& Terlevich (BPT) diagrams and are found to be spatially separated by $\sim$76 pc. Analysis of the optical spatially resolved spectroscopic observations presented in this work favours that Mrk\,622 is a system consisting of a Composite AGN amidst a binary AGN candidate, likely the result of a recent merger. This notwithstanding, outflows from a starburst, or single AGN could also explain the triple nature of the emission lines.

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E. Benítez, J. M. Rodríguez-Espinosa, I. Cruz-González, O. González-Martín, C. A. Negrete, D. Ruschel-Dutra, L. Gutiérrez, E. Jiménez-Bailón. 2017-11-17. A possible binary AGN in Mrk\,622?. https://doi.org/10.1093/mnrasl%2Fslx188

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