ALMA resolves the torus of NGC 1068: Continuum and molecular line emission
Journal article, 2016

We used the Atacama Large Millimeter Array (ALMA) to map the emission of the CO(6-5) molecular line and the 432 mu m continuum emission from the 300 pc sized circumnuclear disk (CND) of the nearby Seyfert 2 galaxy NGC 1068 with a spatial resolution of similar to 4 pc. These observations spatially resolve the CND and, for the first time, image the dust emission, the molecular gas distribution, and the kinematics from a 7-10 pc diameter disk that represents the submillimeter counterpart of the putative torus of NGC 1068. We fitted the nuclear spectral energy distribution of the torus using ALMA and near-and mid-infrared (NIR/MIR) data with CLUMPY torus models. The mass and radius of the best-fit solution for the torus are both consistent with the values derived from the ALMA data alone: M-gas(torus) = (1 +/- 0.3) x 10(5) M-circle dot and R-torus = 3.5 +/- 0.5 pc. The dynamics of the molecular gas in the torus show strong non-circular motions and enhanced turbulence superposed on a surprisingly slow rotation pattern of the disk. By contrast with the nearly edge-on orientation of the H2O megamaser disk, we found evidence suggesting that the molecular torus is less inclined (i = 34 degrees-66 degrees) at larger radii. The lopsided morphology and complex kinematics of the torus could be the signature of the Papaloizou-Pringle instability, long predicted to likely drive the dynamical evolution of active galactic nuclei tori.

galaxies: ISM

galaxies: nuclei

galaxies: Seyfert

galaxies: kinematics and dynamics

galaxies: individual (NGC 1068)

Author

S. G. Burillo

Spanish National Observatory (OAN)

F. Combes

College de France

C. R. Almeida

Instituto Astrofisico de Canarias

University of La Laguna

A. Usero

Spanish National Observatory (OAN)

M. Krips

Institut de RadioAstronomie Millimetrique (IRAM)

A. Alonso-Herrero

Centro de Astrobiologia (CAB)

Susanne Aalto

Chalmers, Earth and Space Sciences, Radio Astronomy and Astrophysics

V. Casasola

Arcetri Astrophysical Observatory

L. K. Hunt

Arcetri Astrophysical Observatory

S. Martin

European Southern Observatory Santiago

Atacama Large Millimeter-submillimeter Array (ALMA)

S. Viti

University College London (UCL)

L. Colina

Universidad Autonoma de Madrid (UAM)

Centro de Astrobiologia (CAB)

Francesco Costagliola

Chalmers, Earth and Space Sciences, Radio Astronomy and Astrophysics

A. Eckart

University of Cologne

A. Fuente

Spanish National Observatory (OAN)

C. Henkel

King Abdulaziz University

Max Planck Society

I. Marquez

CSIC - Instituto de Astrofísica de Andalucía (IAA)

R. Neri

Institut de RadioAstronomie Millimetrique (IRAM)

E. Schinnerer

Max Planck Society

L. J. Tacconi

Max Planck Society

P.P. van der Werf

Leiden University

Astrophysical Journal Letters

2041-8205 (ISSN) 2041-8213 (eISSN)

Vol. 823 1 Art. no. L12- L12

Subject Categories

Astronomy, Astrophysics and Cosmology

DOI

10.3847/2041-8205/823/1/l12

More information

Latest update

5/20/2019