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

¹ INAF – Osservatorio Astronomico di Roma, Via Frascati 33, 00078 Monte Porzio Catone, RM, Italy
e-mail: francesco.saturni@inaf.it
² ASI – Space Science Data Center, Via del Politecnico snc, 00133 Roma, Italy
³ INAF – Istituto di Astrofisica Spaziale e Fisica Cosmica di Milano, Via A. Corti 12, 20133 Milano, Italy
⁴ Università di Bologna, Dip. di Fisica e Astronomia “A. Righi”, Via P. Gobetti 93/2, 40129 Bologna, Italy
⁵ INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, Via P. Gobetti 93/3, 40129 Bologna, Italy
⁶ INAF – Osservatorio Astronomico di Trieste, Via G. B. Tiepolo 11, 34143 Trieste, Italy
⁷ CSIC – Instituto de Astrofísica de Andalucía, Dep.to de Astronomía Extragaláctica, Glorieta de la Astronomía s/n, 18008 Granada, Spain
⁸ Max-Planck Institut für Astronomie, Königstuhl 17, 69117 Heidelberg, Germany
⁹ Instituto de Astrofísica de Canarias, C/ Vía Láctea s/n, 38205 La Laguna, Tenerife, Spain
¹⁰ Universidad de La Laguna, Dep.to de Astrofísica, Av. da Astrofísico F. Sánchez s/n, 38206 La Laguna, Tenerife, Spain

Received: 26 May 2021
Accepted: 26 July 2021

Abstract

The most standard scenario for the evolution of massive galaxies across cosmic time assumes a correspondence based on the interplay between active galactic nuclei (AGN) feedback, which injects large amounts of energy into the host environment, and galaxy mergers, with their ability to trigger massive star formation events and accretion onto supermassive black holes. Interacting systems hosting AGN are useful laboratories for obtaining key insights into both phenomena. In this context, we present an 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 ∼2000 km s⁻¹, an extension of ∼2 kpc, and a mass rate of ∼0.6 M_⊙ yr⁻¹. We also report the existence of an ionized nebular component with v ∼ 1000 km s⁻¹ at ∼6.5 kpc southwards of I20210 South, which 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 for an accurate mapping of the gas kinematics in this AGN pair and evaluate the impact of the outflow on both the interstellar medium and the galaxy environment.