The Narrow Line Region in 3D: mapping AGN feeding and feedback

TL;DR

This paper presents a 3D analysis of the Narrow Line Region in AGN, revealing complex gas kinematics including outflows, inflows, and radiation leakage, with implications for understanding AGN feeding and feedback mechanisms.

Contribution

It provides a novel 3D integral field spectroscopy view of the NLR, highlighting the presence of leakage, diverse gas motions, and early-stage outflows in AGN.

Findings

Ionized gas outflows are typically a few solar masses per year.

Inflows are observed in ionized and warm molecular gas, usually on hundred-parsec scales.

Outflows are often compact, suggesting early stages of cone-shaped outflows.

Abstract

Early studies of nearby Seyfert galaxies have led to the picture that the Narrow Line Region (NLR) is a cone-shaped region of gas ionized by radiation from a nuclear source collimated by a dusty torus, where the gas is in outflow. In this contribution, I discuss a 3D view of the NLR obtained via Integral Field Spectroscopy, showing that: (1) although the region of highest emission is elongated (and in some cases cone-shaped), there is also lower level emission beyond the "ionization cone", indicating that the AGN radiation leaks through the torus; (2) besides outflows, the gas kinematics include also rotation in the galaxy plane and inflows; (3) in many cases the outflows are compact and restricted to the inner few 100pc; we argue that these may be early stages of an outflow that will evolve to an open-ended, cone-like one. Inflows are observed in ionized gas in LINERs, and in warm molecular gas in more luminous AGN, being usually found on hundred of pc scales. Mass outflow rates in ionized gas are of the order of a few solar masses per year, while the mass inflow rates are of the order of tenths of solar masses per year. Mass inflow rates in warm molecular gas are ~4-5 orders of magnitude lower, but these inflows seem to be only tracers of more massive inflows in cold molecular gas that should be observable at mm wavelengths.