The ALMA Discovery of the Rotating Disk and Fast Outflow of Cold Molecular Gas in NGC 1275
Journal article, 2019
We present observations using the Atacama Large Millimeter/submillimeter Array of the CO(2-1), HCN(3-2), and HCO+(3-2) lines in the nearby radio galaxy/brightest cluster galaxy (BCG) NGC 1275 with a spatial resolution of similar to 20 pc. In previous observations, the CO(2-1) emission was detected as radial filaments lying in the east west direction on a kiloparsec scale. We resolved the inner filament and found that it cannot be represented by a simple infalling stream on a sub-kiloparsec scale. The observed complex nature of the filament resembles the cold gas structure predicted by numerical simulations of cold chaotic accretion. Within the central 100 pc, we detected a rotational disk of molecular gas whose mass is similar to 10(8) M-circle dot. This is the first evidence of the presence of a massive cold gas disk on this spatial scale for BCGs. A crude estimate suggests that the accretion rate of the cold gas can be higher than that of hot gas. The disk rotation axis is approximately consistent with the radio-jet axis. This probably suggests that the cold gas disk is physically connected to the innermost accretion disk, which is responsible for jet launching. We also detected absorption features in the HCN(3-2) and HCO+(3-2) spectra against the radio continuum emission mostly radiated by a jet of size similar to 1.2 pc. The absorption features are blueshifted from the systemic velocity by similar to 300-600 km s(-1), suggesting the presence of outflowing gas from the active galactic nucleus (AGN). We discuss the relation of the AGN feeding with cold accretion, the origin of blueshifted absorption, and an estimate of the black hole mass using molecular gas dynamics.
galaxies: active
galaxies: elliptical and lenticular, cD
galaxies: individual (3C 84, NGC 1275, Perseus A)
galaxies: nuclei
Author
H. Nagai
National Astronomical Observatory of Japan
The Graduate University for Advanced Studies (SOKENDAI)
Kyoko Onishi
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Ehime University
N. Kawakatu
National Institute of Technology, Kure College
Y. Fujita
Osaka University
M. Kino
National Astronomical Observatory of Japan
Kogakuin University of Technology and Engineering
Y. Fukazawa
Hiroshima University
J. Lim
The University of Hong Kong
W. Forman
Harvard-Smithsonian Center for Astrophysics
J. Vrtilek
Harvard-Smithsonian Center for Astrophysics
K. Nakanishi
The Graduate University for Advanced Studies (SOKENDAI)
National Astronomical Observatory of Japan
H. Noda
Osaka University
K. Asada
Academia Sinica
K. Wajima
Korea Astronomy and Space Science Institute
Y. Ohyama
Academia Sinica
L. David
Harvard-Smithsonian Center for Astrophysics
K. Daikuhara
Toho University
Astrophysical Journal
0004-637X (ISSN) 1538-4357 (eISSN)
Vol. 883 2 193Subject Categories
Astronomy, Astrophysics and Cosmology
Fusion, Plasma and Space Physics
DOI
10.3847/1538-4357/ab3e6e