Bibcode
Mezcua, M.; Prieto, M. A.; Fernández-Ontiveros, J. A.; Tristram, K.; Neumayer, N.; Kotilainen, J. K.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 452, Issue 4, p.4128-4144
Advertised on:
10
2015
Citations
21
Refereed citations
21
Description
The distribution of warm molecular gas (1000-3000 K), traced by the
near-IR H2 2.12 μm line, has been imaged with a resolution
<0.5 arcsec in the central 1 kpc of seven nearby Seyfert galaxies. We
find that this gas is highly concentrated towards the central 100 pc and
that its morphology is often symmetrical. Lanes of warm H2
gas are observed only in three cases (NGC 1068, NGC 1386 and Circinus)
for which the morphology is much wider and extended than the dust
filaments. We conclude that there is no one-to-one correlation between
dust and warm gas. This indicates that, if the dust filaments and lanes
of warm gas are radial streaming motions of fuelling material, they must
represent two different phases of accretion: the dust filaments
represent a colder phase than the gas close to the nucleus (within
˜100 pc). We predict that the morphology of the nuclear dust at
these scales should resemble that of the cold molecular gas (e.g. CO at
10-40 K), as we show for CenA and NGC 1566 by Atacama Large
Millimeter/submillimeter Array (ALMA) observations, whereas the inner
H2 gas traces a much warmer phase of material identified with
warmer (40-500 K) molecular gas such as CO(6-5) or HCN (as shown by ALMA
for NGC 1068 and NGC 1097). We also find that X-ray heating is the most
likely dominant excitation mechanism of the H2 gas for most
sources.
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The Central PARSEC of Galaxies using High Spatial Resolution Techniques
PARSEC is a multi-wavelength investigation of the central PARSEC of the nearest galaxies. We work on black-hole accretion and its most energetic manifestations: jets and hot spots, and on its circumnuclear environment conditions for star formation. We resort to the highest available angular resolution observations from gamma-rays to the centimetre
Almudena
Prieto Escudero