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arXiv · 2107.12242

Capturing dual AGN activity and kiloparsec-scale outflows in IRAS 20210+1121

Francesco Gabriele Saturni·Giustina Vietri·Enrico Piconcelli·Christian Vignali·Manuela Bischetti·Angela Bongiorno·Sara Cazzoli·Chiara Feruglio·Fabrizio Fiore·Bernd Husemann·Cristina Ramos Almeida
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Abstract

The most accepted scenario for the evolution of massive galaxies across cosmic time predicts a regulation based on the interplay between AGN feedback, which injects large amounts of energy in the host environment, and galaxy mergers, being able to trigger massive star formation events and accretion onto the supermassive black holes. Interacting systems hosting AGN are useful laboratories to get key insights into both phenomena. In this context, we present the analysis of the optical spectral properties of IRAS 20210+1121 (I20210), a merging system at $z = 0.056$. According to X-ray data, this object comprises two interacting galaxies, each hosting an obscured AGN. The optical spectra confirm the presence of AGN features in both galaxies. In particular, we are able to provide a Seyfert classification for I20210 North. The spectrum of I20120 South shows broad blueshifted components associated with the most intense emission lines that indicate the presence of an ionized outflow, for which we derive a maximum velocity of $\sim$2000 km s$^{-1}$, an extension of $\sim$2 kpc and a mass rate of $\sim$0.6 M$_\odot$ yr$^{-1}$. We also report the existence of an ionized nebular component with $v \sim 1000$ km s$^{-1}$ at $\sim$6.5 kpc Southwards of I20210 South, that can be interpreted as disrupted gas ejected from the host galaxy by the action of the outflow. I20120 therefore exhibits a double obscured AGN, with one of them showing evidence of ongoing events for AGN-powered outflows. Future spatially-resolved spectroscopy will allow to accurately map on the gas kinematics in this AGN pair and evaluate the impact of the outflow on both the interstellar medium and galaxy environment.

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Francesco Gabriele Saturni, Giustina Vietri, Enrico Piconcelli, Christian Vignali, Manuela Bischetti, Angela Bongiorno, Sara Cazzoli, Chiara Feruglio, Fabrizio Fiore, Bernd Husemann, Cristina Ramos Almeida. 2021-07-26. Capturing dual AGN activity and kiloparsec-scale outflows in IRAS 20210+1121. https://doi.org/10.1051/0004-6361%2F202141389

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