Ionised gas kinematics in MaNGA AGN

Extents of the narrow-line and kinematically disturbed regions^⋆

¹ Instituto de Astrofisíca de Andalucía, IAA-CSIC, Glorieta de la Astronomia s/n, 18008 Granada, Spain
e-mail: adeconto@iaa.es
² Departamento de Física, CCNE, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil
³ Laboratório Interinstitucional de e-Astronomia – LIneA, Rua Gal. José Cristino 77, Rio de Janeiro, RJ 20921-400, Brazil
⁴ Departamento de Astronomia, Universidade Federal do Rio Grande do Sul, IF, CP 15051, Porto Alegre, 91501-970 RS, Brazil
⁵ Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802, USA
⁶ Institute for Gravitation and the Cosmos, The Pennsylvania State University, University Park, PA 16802, USA
⁷ Apache Point Observatory and New Mexico State University, Sunspot, NM 88349, USA
⁸ Sternberg Astronomical Institute, Moscow State University, Moscow, Russia
⁹ Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, 80 Nandan Road, Shanghai 200030, PR China
¹⁰ University of the Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, PR China
¹¹ European Southern Observatory, Karl-Schwarzschildstr. 2, 85748 Garching bei München, Germany
¹² Observatório Nacional – MCT, Rua General José Cristino 77, Rio de Janeiro, RJ 20921-400, Brazil
¹³ Universidade do Vale do Paraíba, Av. Shishima Hifumi, 2911, 12244-000 São José dos Campos, SP, Brazil

Received: 19 February 2021
Accepted: 3 January 2022

Abstract

Context. Feedback from active galactic nuclei (AGNs) in general seems to play an important role in the evolution of galaxies, although the impact of AGN winds on their host galaxies is still unknown in the absence of a detailed analysis.

Aims. We aim to analyse the kinematics of a sample of 170 AGN host galaxies as compared to those of a matched control sample of non-active galaxies from the MaNGA survey in order to characterise and estimate the extents of the narrow-line region (NLR) and of the kinematically disturbed region (KDR) by the AGN.

Methods. We defined the observed NLR radius (r_NLR, o) as the farthest distance from the nucleus within which both [O III]/Hβ and [N II]/Hα ratios fall in the AGN region of the BPT diagram, and the Hα equivalent width was required to be larger than 3.0 Å. The extent of the KDR (r_KDR, o) is defined as the distance from the nucleus within which the AGN host galaxies show a more disturbed gas kinematics than the control galaxies.

Results. The AGN [O III]λ5007 luminosity ranges from 10³⁹ to 10⁴¹ erg s⁻¹, and the kinematics derived from the [O III] line profiles reveal that, on average, the most luminous AGNs (L[O III] > 3.8 × 10⁴⁰ erg s⁻¹) possess higher residual differences between the gaseous and stellar velocities and velocitie dispersions than their control galaxies in all the radial bins. Spatially resolved NLRs and KDRs were found in 55 and 46 AGN host galaxies, with corrected radii 0.2 < r_KDR, c < 2.3 kpc and 0.4 < r_NLR, c < 10.1 kpc and a relation between the two given by log r_KDR, c = (0.53 ± 0.12) log r_NLR, c + (1.07 ± 0.22), respectively. On average, the extension of the KDR corresponds to about 30% of that of the NLR. Assuming that the KDR is due to an AGN outflow, we have estimated ionised gas mass outflow rates that range between 10⁻⁵ and ∼1 M_⊙ yr⁻¹, and kinetic powers that range from 10³⁴ to 10⁴⁰ erg s⁻¹.

Conclusions. Comparing the power of the AGN ionised outflows with the AGN luminosities, they are always below the 0.05 L_AGN model threshold for having an important feedback effect on their respective host galaxies. The mass outflow rates (and power) of our AGN sample correlate with their luminosities, populating the lowest AGN luminosity range of the correlations previously found for more powerful sources.