Astronomy and Astrophysics – Astrophysics
Scientific paper
2000-12-22
Astronomy and Astrophysics
Astrophysics
Accepted for pub. in A&A, 12 pages, 12 figures
Scientific paper
10.1051/0004-6361:20000523
We present new stellar kinematical profiles of four galaxy hosts of active galactic nuclei, using the CO bandhead around 2.3 micron with the ISAAC/VLT spectrograph. We find that the nuclear bars or discs, embedded in large-scale primary bars, have all a decoupled kinematics, in the sense that the maximum of the rotational velocity occurs in the nuclear region. In three cases (NGC 1097, NGC 1808 and NGC 5728), the velocity dispersion displays a significant drop at the nucleus, a rarely observed phenomenon. We also detect kinematical asymmetries (m=1 mode) along the nuclear bar major-axis of NGC 1808 and NGC 5728, dynamical counterparts of corresponding asymmetries in the surface brightness. We have derived simple dynamical models in an attempt to fit the kinematics of each galaxy and reconstruct the full velocity field. For all four targets, the fits are good, and confirm the presence of the decoupled nuclear components. These models cannot however reproduce the observed central drop in the dispersion. We suggest that this drop is due to a transient cold nuclear disc, fuelled by gas inflow along the bar, that has recently formed new stars.
Combes François
Emsellem Eric
Friedli Daniel
Greusard D.
Leon Stephane
No associations
LandOfFree
Dynamics of embedded bars and the connection with AGN. I. ISAAC/VLT stellar kinematics does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Dynamics of embedded bars and the connection with AGN. I. ISAAC/VLT stellar kinematics, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dynamics of embedded bars and the connection with AGN. I. ISAAC/VLT stellar kinematics will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-613846