The host galaxies of AGN: are there signs of a connection between mergers, starbursts and AGN?
Wide-Field Surveys and QSO Physics
Carolin Villforth
Timothy Hamilton, Fred Hamann, Vivienne Wild, Paul Hewett
University of St Andrews
One open question in astronomy is how Active Galactic Nuclei (AGN) are
triggered. Fueling AGN requires supplying gas to the very centre of
galaxies on timescales comparable to the lifetime of the AGN. This is
challenging because the gas needs to be stripped of most of its angular
momentum on time-scales much shorter than the dynamical time-scale of
the host galaxy. Fueling gas to the central region increases the gas density
in that region, and is therefore likely to trigger star formation.
Starbursts and AGN activity are therefore expected to be closely
connected. One of the suspected triggers of AGN activity are mergers of
gas-rich galaxies. I will present results from imaging studies of AGN
host galaxies which show that mergers are not prevalent over a wide
range of AGN luminosities. One possible explanation for the lack of
enhanced merger features in AGN hosts is a long delay between the merger
event and the onset of AGN activity. I will present preliminary results
from a study which will allow us to address this question.
16:30 - 18:00