|
|
Paper: |
Warps and Bars in Nearby Active Galaxies Traced by the Molecular Gas |
Volume: |
240, Gas and Galaxy Evolution: A Conference in Honor of the 20th Anniversary of the VLA |
Page: |
280 |
Authors: |
Schinnerer, E.; Eckart, A.; Tacconi, L. J.; Genzel, R.; Scoville, N. Z.; Moustakas, L. A. |
Abstract: |
We have obtained high angular resolution 12CO mm-data for five nearby active galaxies with the IRAM Plateau de Bure interferometer (PdBI) and for two galaxies with the Caltech Owens Valley Radio Observatory interferometer (OVRO). The data show a variety of structures like rings, bars and spiral arms. The analysis reveals non-circular motions in the nuclear regions of these galaxies. Modeling of the kinematics was done for NGC 1068 and NGC 3227 under the assumptions: (a) that the molecular gas is dissipative and (b) can, therefore, only move on either planar elliptical or tilted circular orbits. The best fit obtained for both galaxies contains a warped thin nuclear gas disk. Such a disk can provide material for the obscuration of the active galactic nucleus (AGN) and might link the AGN itself to the host galaxy. Due to the high sensitivity of the data, we were able to detect for the first time in these galaxies molecular gas down to radii of ~10 pc. This gas shows high velocity offsets from the systemic velocity indicating enclosed masses of ~ 107 Msolar for NGC 3227 and ~ 108 Msolar for NGC 1068. Recent observations of LINER galaxies revealed similar features such as line splitting, asymmetric line profiles in NGC 4736 and also indications for bar streaming in NGC 4303. |
|
|
|
|