ALMA OBSERVATIONS OF THE SUBMILLIMETER DENSE MOLECULAR GAS TRACERS IN THE LUMINOUS TYPE-1 ACTIVE NUCLEUS OF NGC 7469
Journal article, 2015
We present Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 1 observations of the central kiloparsec region of the luminous type. 1 Seyfert galaxy NGC 7469 with unprecedented high resolution (0.'' 5x0.'' 4 = 165 x 132 pc) at submillimeter wavelengths. Utilizing the wide. bandwidth of ALMA, we simultaneously obtained HCN(4-3), HCO+(4-3), CS(7-6), and partially CO(3-2) line maps, as well as the 860 mu m continuum. The region consists of the central similar to 1 '' component and the surrounding starburst ring with a radius of similar to 1.'' 5-2.'' 5. Several structures connect these components. Except for CO(3-2), these dense gas tracers are significantly concentrated toward the central similar to 1 '', suggesting their suitability to probe the nuclear regions of galaxies. Their spatial distribution resembles well those of centimeter and mid-infrared continuum emissions, but it is anticorrelated with the optical one, indicating the existence of dust-obscured star formation. The integrated intensity ratios of HCN(4-3)/HCO+(4-3) and HCN(4-3)/CS(7-6) are higher at the active galactic nucleus (AGN) position than at the starburst ring, which is consistent with our previous findings (submillimeter-HCN enhancement). However, the HCN(4-3)/HCO+(4-3) ratio at the AGN position of NGC 7469 (1.11 +/- 0.06) is almost half of the corresponding value of the low-luminosity type. 1 Seyfert galaxy NGC 1097 (2.0 +/- 0.2), despite the more than two orders of magnitude higher X-ray luminosity of NGC 7469. But the ratio is comparable to that of the close vicinity of the AGN of NGC 1068 (similar to 1.5). Based on these results, we speculate that some heating mechanisms other than X-ray (e.g., mechanical heating due to an AGN jet) can contribute significantly for shaping the chemical composition in NGC 1097.
nuclei
nzel r
galaxies: active
broad-line region
1995
galactic
seyfert-galaxies
galaxies: ISM
photon-dominated regions
cloverleaf quasar
supermassive black-hole
nearby
galaxies: individual (NGC 7469)
x-ray
Astronomy & Astrophysics
p129
astrophysical journal
ISM: molecules
star-formation
infrared galaxies
agn-driven outflow
v444
Author
T. Izumi
University of Tokyo
K. Kohno
Research Center for the Early Universe
University of Tokyo
Susanne Aalto
Chalmers, Earth and Space Sciences, Radio Astronomy and Astrophysics
A. Doi
JAXA Institute of Space and Astronautical Science
D. Espada
National Institutes of Natural Sciences - National Astronomical Observatory of Japan
Atacama Large Millimeter-submillimeter Array
Sokendai Graduate University for Advanced Studies
K. Fathi
Stockholm Observatory
N. Harada
Institute of Astrophysics and Astronomy, Academia Sinica Taiwan
B. Hatsukade
National Institutes of Natural Sciences - National Astronomical Observatory of Japan
T. Hattori
National Institutes of Natural Sciences - National Astronomical Observatory of Japan
P. Y. Hsieh
National Central University Taiwan
Institute of Astrophysics and Astronomy, Academia Sinica Taiwan
S. Ikarashi
University of Tokyo
European Southern Observatory
M. Imanishi
National Institutes of Natural Sciences - National Astronomical Observatory of Japan
Sokendai Graduate University for Advanced Studies
D. Iono
National Institutes of Natural Sciences - National Astronomical Observatory of Japan
Sokendai Graduate University for Advanced Studies
S. Ishizuki
National Institutes of Natural Sciences - National Astronomical Observatory of Japan
M. Krips
IRAM Institut de RadioAstronomie Millimetrique
S. Martin
IRAM Institut de RadioAstronomie Millimetrique
S. Matsushita
Institute of Astrophysics and Astronomy, Academia Sinica Taiwan
D. S. Meier
New Mexico Institute of Mining and Technology
H. Nagai
National Institutes of Natural Sciences - National Astronomical Observatory of Japan
N. Nakai
University of Tsukuba
T. Nakajima
Nagoya University
K. Nakanishi
Atacama Large Millimeter-submillimeter Array
National Institutes of Natural Sciences - National Astronomical Observatory of Japan
Sokendai Graduate University for Advanced Studies
H. Nomura
Tokyo Institute of Technology
M. W. Regan
STScI
E. Schinnerer
Max Planck Institut fur Astronomie
K. Sheth
National Radio Astronomy Observatory
S. Takano
Nihon University
Y. Tamura
University of Tokyo
Y. Terashima
Ehime University
T. Tosaki
Joetsu University of Education
J. L. Turner
University of California, Los Angeles
H. Umehata
University of Tokyo
Tommy Wiklind
Atacama Large Millimeter-submillimeter Array
Astrophysical Journal
0004-637X (ISSN) 1538-4357 (eISSN)
Vol. 811 1 Article Number: 39- 39Subject Categories (SSIF 2011)
Astronomy, Astrophysics and Cosmology
DOI
10.1088/0004-637x/811/1/39