Host galaxies of luminous type II AGN: Winds, shocks, and comparisons to The SAMI Galaxy Survey

We present IFS observations of luminous (log(L[O III]/L⊙) > 8.7) local (z < 0.11) type II AGN, and demonstrate that winds are ubiquitous within this sample and have a direct influence on the ISM of the host galaxies. We use both non-parametric (e.g. line width and asymmetry) and multi-Gaussian...

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Bibliographic Details
Main Authors: McElroy, Rebecca, Croom, Scott, Pracy, Michael
Format: Conference Object
Language:unknown
Published: 2016
Subjects:
Online Access:https://research.usq.edu.au/item/z75x3/host-galaxies-of-luminous-type-ii-agn-winds-shocks-and-comparisons-to-the-sami-galaxy-survey
Description
Summary:We present IFS observations of luminous (log(L[O III]/L⊙) > 8.7) local (z < 0.11) type II AGN, and demonstrate that winds are ubiquitous within this sample and have a direct influence on the ISM of the host galaxies. We use both non-parametric (e.g. line width and asymmetry) and multi-Gaussian fitting to decompose the complex emission profiles close to the AGN. We find line widths containing 80% flux in the range 400 - 1600 km/s with a mean of 790 ± 90 km/s, such high velocities are strongly suggestive that these AGN are driving ionized outflows. Additionally, multi-Gaussian fitting reveals that 14/17 of our targets require 3 separate kinematic components in the ionized gas in their central regions. The broadest components of these fits have FWHM = 530 - 2520 km/s, with a mean value of 920 ± 50 km/s. By simultaneously fitting both the Hβ/[O III] and Hα/[N II] complexes we construct ionization diagnostic diagrams for each component. 13/17 of our galaxies show a significant (> 95 %) correlation between the [N II]/Hα ratio and the velocity dispersion of the gas. Such a correlation is the natural consequence of a contribution to the ionization from shock excitation and we argue that this demonstrates that the outflows from these AGN are directly impacting the surrounding ISM within the galaxies. In addition, we use stellar absorption features to measure kinematics for these AGN host galaxies and those of a control sample selected from the SAMI Galaxy Survey to search for evidence of these luminous AGN being preferentially hosted by disturbed or merging systems.