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arXiv · 1609.04076

Unravelling the complex structure of AGN-driven outflows: II. Photoionization and energetics

Marios Karouzos·Jong-Hak Woo·Hyun-Jin Bae
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Abstract

Outflows have been shown to be prevalent in galaxies hosting luminous active galactic nuclei (AGNs) and present a physically plausible way to couple the AGN energy output with the interstellar medium of their hosts. Despite their prevalence, accurate characterization of these outflows has been challenging. In the second of a series of papers, we use Gemini Multi-Object Spectrograph IFU data of 6 local (z<0.1) and moderate-luminosity Type 2 AGNs to study the ionization properties and energetics of AGN-driven outflows. We find strong evidence that connect the extreme kinematics of the ionized gas with the AGN photoionization. The kinematic component related to the AGN-driven outflow is clearly separated from other kinematic components, such as virial motions or rotation, on the velocity and velocity dispersion diagram. Our spatially resolved kinematic analysis reveals that from 30% up to 90% of the total mass and kinetic energy of the outflow is contained within the central kpc of the galaxy. The spatially integrated mass and kinetic energy of the gas entrained in the outflow correlates well with the AGN bolometric luminosity and results in energy conversion efficiencies between 0.01% and 1%. Intriguingly, we detect ubiquitous signs of ongoing circumnuclear star formation. Their small size, the centrally contained mass and energy, and the universally detected circumnuclear star formation cast doubts on the potency of these AGN-driven outflows as agents of galaxy-scale negative feedback.

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Marios Karouzos, Jong-Hak Woo, Hyun-Jin Bae. 2016-09-14. Unravelling the complex structure of AGN-driven outflows: II. Photoionization and energetics. https://doi.org/10.3847/1538-4357%2F833%2F2%2F171

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