Breaking the Obscuring Screen: A Resolved Molecular Outflow in a Buried QSO

TL;DR

This study uses high-resolution near-infrared observations to reveal a compact molecular outflow in a buried QSO, providing insights into early dust clearance stages in such active galactic nuclei.

Contribution

It presents the first high-resolution imaging of a molecular outflow in a buried QSO, showing detailed outflow structure and velocities at 100 pc scale.

Findings

Molecular outflow reaches velocities of -1300 km/s.

Outflow is perpendicular to the disk, forming a bicone.

Spatial resolution improved by over 10 times compared to previous studies.

Abstract

We present Keck laser guide star adaptive optics observations of the nearby buried QSO F08572+3915:NW. We use near-infrared integral field data taken with OSIRIS to reveal a compact disk and molecular outflow using Pa-alpha and H_2 rotational-vibrational transitions at a spatial resolution of 100 pc. The outflow emerges perpendicular to the disk into a bicone of one-sided opening angle 100 degrees up to distances of 400 pc from the nucleus. The integrated outflow velocities, which reach at least -1300 km/s, correspond exactly to those observed in (unresolved) OH absorption, but are smaller (larger) than those observed on larger scales in the ionized (neutral atomic) outflow. These data represent a factor of >10 improvement in the spatial resolution of molecular outflows from mergers/QSOs, and plausibly represent the early stages of the excavation of the dust screen from a buried QSO.