04/30/02
XILOURIS EMMANUEL CEA/SACLAY
GIF-sur-Yvette SF2A-
91191 SACLAY, FRANCE
Presentation 1 : Oral
A morphological comparison between the central region in AGN and normal galaxies using HST data
E.M. Xilouris, I.E. Papadakis
We study the morphology of the central region of a sample of AGNs and a ``control'' sample of normal galaxies using archival observations of the WFPC2 instrument onboard the HST. We perform quantitative comparisons of different subgroups of our sample of galaxies by calculating the average amplitude of the structures that are revealed when applying the ellipse fitting technique. We find that all AGN show significant micro-structures in their central regions. Among the non-AGN galaxies those of early-type show no structures, while the late-type normal galaxies show structures similar to those detected in AGNs. We discuss briefly the implications of our results in view of the hypothesis that all galaxies host a supermassive black hole.