71 research outputs found
The Centimeter to Submillimeter Broad Band Radio Spectrum of the Central Compact Component in A Nearby Type-II Seyfert Galaxy NGC 1068
We analyze all the available Atacama Large Millimeter / submillimeter Array
archival data of the nearby Type-II Seyfert galaxy NGC 1068, including new 100
GHz data with the angular resolution of 0\farcs05, which was not included in
previous continuum spectral analysis. By combining with the literature data
based on the Very Large Array, we investigate the broadband radio continuum
spectrum of the central pc region of NGC 1068. We found that the
flux density is between 10-20 mJy at 5-700 GHz. Due to the inability
of the model in previous studies to account for the newly added 100 GHz data
point, we proceeded to update the models and make the necessary adjustments to
the parameters. One possible interpretation of this broadband radio spectrum is
a combination of emission from the jet base, the dusty torus, and the compact
X-raying corona with the magnetic field strength of G on scales of
Schwarzschild radii from the central black hole. In order to firmly
identify the compact corona by omitting any other possible extended components
(e.g., free-free emission from ionized gas around), high-resolution/sensitivity
observations achieved by next-generation interferometers will be necessary.Comment: 10 pages, 4 figures, 3 tables, accepted for publication in PAS
Nobeyama 45-m CO J=1-0 Observations of Luminous Type 1 AGNs at
We have performed CO J =1-0 observations of ten galaxies hosting luminous
() type 1 active galactic nuclei
(AGNs) with the Nobeyama 45-m radio telescope. The targets are selected because
they are expected to be rich in molecular gas based on their high nebular dust
extinction (). However, no significant CO emission lines were
detected in any of the targets. The upper limits of the CO J=1-0 luminosities
are lower than expected given the molecular gas mass inferred from the nebular
. This inconsistency may be due to overestimated values
due to the lack of stellar absorption correction. Considering more reliable
values, the CO J=1-0 non-detections by Nobeyama 45-m are natural.
This suggests that our results do not contradict the conversion methods from
to molecular gas mass proposed in the literature. This survey
suggests that careful measurements as well as CO observations are
still needed to improve the measurements or estimates of the molecular gas
content of galaxies hosting luminous AGNs.Comment: 8 pages, 6 figures, Accepted for publication in PAS
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