Compact molecular disc and ionized gas outflows within 350 pc of the active nucleus of Mrk 1066

TL;DR

This study investigates the inner 350 pc of the Seyfert galaxy Mrk 1066, revealing a compact rotating molecular disc and ionized gas outflows driven by the active nucleus, using high-resolution near-infrared integral field spectroscopy.

Contribution

It provides detailed kinematic maps of stars and gas, identifying a nuclear disc and outflows, and quantifies the gas mass and outflow rate, advancing understanding of AGN feeding and feedback mechanisms.

Findings

Identification of a ~70 pc rotating molecular disc.

Detection of ionized gas outflows with velocities up to 500 km/s.

Estimated gas outflow rate of 0.06 solar masses per year.

Abstract

We present stellar and gaseous kinematics of the inner 350 pc radius of the Seyfert galaxy Mrk1066 derived from J and Kl bands data obtained with the Gemini NIFS at a spatial resolution of 35 pc. The stellar velocity field is dominated by rotation in the galaxy plane but shows an S-shape distortion along the galaxy minor axis which seems to be due to an oval structure seen in an optical continuum image. Along this oval, between 170 and 280 pc from the nucleus we find a partial ring of low sigma (~50 km/s) attributed to an intermediate age stellar population. Fro measurements of the emission-line fluxes and profiles ([PII]1.19um, [FeII]1.26um, Pa-beta and H2 2.12um), we have constructed maps for the gas centroid velocity, velocity dispersion, as well as channel maps. The velocity fields for all emission lines are dominated by a similar rotation pattern to that observed for the stars, but are distorted by the presence of two structures: (i) a compact rotating disc with radius r~70 pc; (ii) outflows along the radio jet which is oriented approximately along the galaxy major axis. The compact rotating disc is more conspicuous in the H2 emitting gas, which presents the smallest sigma values and most clear rotation pattern, supporting a location in the galaxy plane. We estimate a gas mass for the disc of ~10^7Msun. The H2 kinematics further suggests that the nuclear disc is being fed by gas coming from the outer regions. The outflow is more conspicuous in the [FeII] emitting gas, which presents the highest sigma values (up to 150 km/s) and the highest blue and redshifts of up to 500 km/s, while the highest stellar rotation velocity is only 130 km/s. We estimate a mass-outflow rate in ionized gas of 0.06 Msun/yr. The derived kinematics for the emitting gas is similar to that observed in previous studies supporting that the H2 is a tracer of the AGN feeding and the [FeII] of its feedback.