High-Velocity Bipolar Molecular Emission from an AGN Torus

TL;DR

This paper reports ALMA observations of CO emission in NGC 1068, revealing a bipolar outflow and possible rotation in the AGN torus, supporting the disk-wind model for the obscuring structure.

Contribution

First high-resolution ALMA detection of bipolar molecular outflow from an AGN torus, providing evidence for the disk-wind scenario.

Findings

Detection of 12x7 pc CO emission structure aligned with the nucleus

High-velocity bipolar outflow nearly perpendicular to the disk

Velocity field suggests possible rotation around the disk axis

Abstract

We have detected in ALMA observations CO J = 6 - 5 emission from the nucleus of the Seyfert galaxy NGC 1068. The low-velocity (up to +/- 70 km/s relative to systemic) CO emission resolves into a 12x7 pc structure, roughly aligned with the nuclear radio source. Higher-velocity emission (up to +/- 400 km/s) is consistent with a bipolar outflow in a direction nearly perpendicular (roughly 80 degrees) to the nuclear disk. The position-velocity diagram shows that in addition to the outflow, the velocity field may also contain rotation about the disk axis. These observations provide compelling evidence in support of the disk-wind scenario for the AGN obscuring torus.