Documentation scienceplus.abes.fr version Bêta

À propos de : Dynamics of embedded bars and the connection with AGN        

AttributsValeurs
type
Is Part Of
Subject
subtitle
  • I. ISAAC/VLT stellar kinematics
Title
  • Dynamics of embedded bars and the connection with AGN
Date
has manifestation of work
related by
Author
Abstract
  • We present new stellar kinematical profiles of four galaxy hosts of active galactic nuclei, using the 12CO bandhead around 2.3 μm 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.
article type
publisher identifier
  • aa10402
Date Copyrighted
Rights
  • © ESO, 2001
Rights Holder
  • ESO
is part of this journal
is primary topic of



Alternative Linked Data Documents: ODE     Content Formats:       RDF       ODATA       Microdata