Supermassive black holes are thought to be ubiquitous in bulge-dominated galaxies and the standard model of Active Galactic Nuclei (AGN) invokes the release of gravitational energy due to accretion of material onto a central black hole. What determines the presence and degree of nuclear activity, however, remains an unanswered question. Unlike quasar activity, which seems to coincide with the build-up of galactic-size structures, activity in nearby AGN with well-established host galaxies, must involve re-activation of their central black holes. Neutral hydrogen (HI) is a key tracer of galactic structure and dynamics and responds most readily to perturbations caused by tidal disturbance and non-axisymetric gravitational potentials - perturbations which have been mooted as possible triggers of nuclear activity. I present here an HI imaging study of a heterogeneous sample of nine nearby Seyfert galaxies and describe plans for a new HI survey which aims to investigate the role of the host gas in triggering and fuelling of nuclear activity on a statistical basis.
|Astronomical Society of the Pacific Conference Series
|Active Galactic Nuclei: from Central Engine to Host Galaxy, 2002
|23/07/02 → 27/07/02