Inflows and outflows in nearby active galactic nuclei from integral field spectroscopy

TL;DR

This study uses integral field spectroscopy to analyze the inner regions of nearby active galactic nuclei, revealing inflows and outflows of gas that influence AGN fueling and feedback mechanisms.

Contribution

It provides detailed kinematic measurements of gas flows in the central few hundred parsecs of nearby AGN, highlighting the roles of inflows and outflows in galaxy nuclei.

Findings

Inflow velocities of ~50 km/s along nuclear spiral arms.

Outflows with velocities up to ~600 km/s in ionized gas.

Mass outflow rates significantly exceed accretion rates, indicating feedback processes.

Abstract

I report recent results on the kinematics of the inner few hundred parsecs (pc) around nearby active galactic nuclei (AGN) at a sampling of a few pc to a few tens of pc, using optical and near-infrared (near-IR) integral field spectroscopy obtained with the Gemini telescopes. The stellar kinematics of the hosts - comprised mostly of spiral galaxies - are dominated by circular rotation in the plane of the galaxy. Inflows with velocities of ~ 50 km/s have been observed along nuclear spiral arms in (optical) ionized gas emission for low-luminosity AGN and in (near-IR) molecular gas emission for higher-luminosity AGN. We have also observed gas rotating in the galaxy plane, sometimes in compact (few tens of pc) disks which may be fuelling the AGN. Outflows have been observed mostly in ionized gas emission from the narrow-line region, whose flux distributions and kinematics frequently correlate with radio flux distributions. Channel maps along the emission-line profiles reveal velocities as high as ~ 600 km/s. Mass outflow rates in ionized gas range from 0.01 to 0.001 solar masses per year and are 10-100 times larger than the mass accretion rates to the AGN, supporting an origin for the bulk of the outflow in gas from the galaxy plane entrained by a nuclear jet or accretion disk wind.