Bibcode
Alonso-Herrero, A.; Pereira-Santaella, M.; García-Burillo, S.; Davies, R. I.; Combes, F.; Asmus, D.; Bunker, A.; Díaz-Santos, T.; Gandhi, P.; González-Martín, O.; Hernán-Caballero, A.; Hicks, E.; Hönig, S.; Labiano, A.; Levenson, N. A.; Packham, C.; Ramos Almeida, C.; Ricci, C.; Rigopoulou, D.; Rosario, D.; Sani, E.; Ward, M. J.
Bibliographical reference
The Astrophysical Journal, Volume 859, Issue 2, article id. 144, 12 pp. (2018).
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6
2018
Journal
Citations
77
Refereed citations
72
Description
We present ALMA Band 6 12CO(2–1) line and rest-frame
232 GHz continuum observations of the nearby Compton-thick Seyfert
galaxy NGC 5643 with angular resolutions 0.″11–0.″26
(9–21 pc). The CO(2–1) integrated line map reveals emission
from the nuclear and circumnuclear region with a two-arm nuclear spiral
extending ∼10″ on each side. The circumnuclear CO(2–1)
kinematics can be fitted with a rotating disk, although there are
regions with large residual velocities and/or velocity dispersions. The
CO(2–1) line profiles of these regions show two different velocity
components. One is ascribed to the circular component and the other to
the interaction of the AGN outflow, as traced by the [O III]λ5007
Å emission, with molecular gas in the disk a few hundred parsecs
from the AGN. On nuclear scales, we detected an inclined CO(2–1)
disk (diameter 26 pc, FWHM) oriented almost in a north–south
direction. The CO(2–1) nuclear kinematics can be fitted with a
rotating disk that appears to be tilted with respect to the large-scale
disk. There are strong non-circular motions in the central
0.″2–0.″3 with velocities of up to 110 km
s‑1. In the absence of a nuclear bar, these motions
could be explained as radial outflows in the nuclear disk. We estimate a
total molecular gas mass for the nuclear disk of M(H2) = 1.1
× 107 M ⊙ and an H2 column
density toward the location of the AGN of N(H2) ∼ 5
× 1023 cm‑2, for a standard
CO-to-H2 conversion factor. We interpret this nuclear
molecular gas disk as the obscuring torus of NGC 5643 as well as the
collimating structure of the ionization cone.
Related projects
Nuclear Activity in Galaxies: a 3D Perspective from the Nucleus to the Outskirts
This project consists of two main research lines. First, the study of quasar-driven outflows in luminous and nearby obscured active galactic nuclei (AGN) and the impact that they have on their massive host galaxies (AGN feedback). To do so, we have obtained Gran Telescopio CANARIAS (GTC) infrared and optical observations with the instruments
Cristina
Ramos Almeida