Internet Archive Scholar

Resolving the Nuclear Obscuring Disk in the Compton-thick Seyfert Galaxy NGC 5643 with ALMA

A. Alonso-Herrero, M. Pereira-Santaella, S. García-Burillo, R. I. Davies, F. Combes, D. Asmus, A. Bunker, T. Díaz-Santos, P. Gandhi, O. González-Martín, A. Hernán-Caballero, E. Hicks (+10 others)
2018 Astrophysical Journal  

Preserved Fulltext

fulltext thumbnail
Web Archive Capture PDF (3.3 MB)
https://web.archive.org/web/20190429110551/http://dro.dur.ac.uk/25334/1/25334.pdf

A copy of this work was available on the public web and has been preserved in the Wayback Machine. The capture dates from 2019; you can also visit the original URL. The file type is application/pdf.

Other Versions

2018 accepted
arXiv:1804.04842v2 fatcat:xb2a46cl7vhyjid26wkrcoupma
2018 pre-print
arXiv:1804.04842v1 fatcat:tbjtcdl6x5bapdybtlm7sua3n4
We present ALMA Band 6 ^12CO(2--1) line and rest-frame 232GHz continuum observations of the nearby Compton-thick Seyfert galaxy NGC5643 with angular resolutions 0.11-0.26arcsec (9-21pc). The CO(2--1) integrated line map reveals emission from the nuclear and circumnuclear region with a two-arm nuclear spiral extending 10arcsec 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
more » ... s. 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]5007AA 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 which appears to be tilted with respect to the large scale disk. There are strong non-circular motions in the central 0.2-0.3 arcsec with velocities of up to 110km/s. 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( H_2)=1.1× 10^7 M_ and an H_2 column density toward the location of the AGN of N( H_2)∼ 5 × 10^23 cm^-2, for a standard CO-to-H_2 conversion factor. We interpret this nuclear molecular gas disk as the obscuring torus of NGC5643 as well as the collimating structure of the ionization cone.
doi:10.3847/1538-4357/aabe30 fatcat:6xtlkm6cwfgqpe24lbsn6wliji
Multiple Versions
Citation

A. Alonso-Herrero, M. Pereira-Santaella, S. García-Burillo, R. I. Davies, F. Combes, D. Asmus, A. Bunker, T. Díaz-Santos, P. Gandhi, O. González-Martín, A. Hernán-Caballero, E. Hicks, S. Hönig, A. Labiano, N. A. Levenson, C. Packham, C. Ramos Almeida, C. Ricci, D. Rigopoulou, D. Rosario, E. Sani, M. J. Ward. "Resolving the Nuclear Obscuring Disk in the Compton-thick Seyfert Galaxy NGC 5643 with ALMA." Astrophysical Journal 859.2 (2018) 144