J/A+A/632/A66 PKS 1549-79 ALMA data cubes & continuum images (Oosterloo+, 2019)
ALMA observations of PKS 1549-79:
a case of feeding and feedback in a young radio quasar.
Oosterloo T.A., Morganti R., Tadhunter C.N., Oonk J.B.R., Bignall H.E.,
Tzioumis T., Reynolds C.
<Astron. Astrophys. 632, A66 (2019)>
=2019A&A...632A..66O 2019A&A...632A..66O (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, radio ; Radio sources
Keywords: galaxies: active - galaxies : individual: PKS 1549-79 -
ISM: jets and outflows - radio lines: galaxies
Abstract:
We present CO(1-0) and CO(3-2) Atacama Large Millimeter/submillimeter
Array observations of the molecular gas in PKS 1549-79, as well as
mm and very long baseline interferometry 2.3-GHz continuum
observations of its radio jet. PKS 1549-79 is one of the closest
young, radio-loud quasars caught in an on-going merger in which the
active galactic nucleus (AGN) is in the first phases of its evolution.
We detect three structures tracing the accretion and the outflow of
molecular gas: kpc-scale tails of gas accreting onto PKS1549-79 from
a merger, a circumnuclear disc in the inner few hundred parsec, and a
very broad (>2300km/s) component detected in CO(1-0) at the
position of the AGN. Thus, in PKS 1549-79 we see the co-existence of
accretion and the ejection of gas. The line ratio CO(3-2)/CO(1-0)
suggests that the gas in the circumnuclear-disc has both high
densities and high kinetic temperatures. We estimate a mass outflow
rate of at least 650M☉/yr. This massive outflow is confined to
the inner region (r<120pc) of the galaxy, which suggests that the AGN
drives the outflow. Considering the amount of molecular gas available
in the central nuclear disc and the observed outflow rate, we estimate
a time scale of 105yr over which the AGN would be able to destroy
the circumnuclear disc, although gas from the merger may come in from
larger radii, rebuilding this disc at the same time. The AGN appears
to self-regulate gas accretion to the centre and onto the
super-massive black hole. Surprisingly, from a comparison with Hubble
Space Telescope data, we find that the ionised gas outflow is more
extended. Nevertheless, the warm outflow is about two orders of
magnitude less massive than the molecular outflow. PKS 1549-79 does
not seem to follow the scaling relation between bolometric luminosity
and the relative importance of warm ionised and molecular outflows
claimed to exist for other AGN. We argue that, although PKS 1549-79
hosts a powerful quasar nucleus and an ultra-fast outflow, the radio
jet plays a significant role in producing the outflow, which creates a
cocoon of disturbed gas that expands into the circumnuclear disc.
Description:
Data cubes of the CO molecular gas in the quasar PKS 1549-79 in the
transitions (1-0) and (3-2), and ALMA continuum images at 100- and
300GHz
Objects:
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RA (2000) DE Designation(s)
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15 56 58.87 -79 14 04.3 PKS 1549-79 = QSO B1549-790
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 159 8 List of images and datacubes
fits/* . 8 Individual fits images and datacubes
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 9 F9.5 deg RAdeg Right Ascension of center (J2000)
10- 18 F9.5 deg DEdeg Declination of center (J2000)
20- 23 I4 --- Nx Number of pixels along X-axis
25- 28 I4 --- Ny Number of pixels along Y-axis
30- 32 I3 --- Nz ? Number of slices
34- 54 A21 "datime" Obs.date Observation date
56- 67 E12.5 m/s bVELO ? Lower value of VELO-HEL interval
for the datacubes
69- 79 E11.5 m/s BVELO ? Upper value of VELO-HEL interval
for the datacubes
81- 88 F8.2 m/s dVELO ? Velocity resolution for the datacubes
90- 95 I6 Kibyte size Size of FITS file
97-115 A19 --- FileName Name of FITS file, in subdirectory fits
117-159 A43 --- Title Title of the FITS file
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Acknowledgements:
Tom Oosterloo, oosterloo(at)astron.nl
(End) Patricia Vannier [CDS] 12-Nov-2019