The Role of Major Mergers and Nuclear Star Formation in Nearby Obscured
  Quasars
  We investigate the triggering mechanism and the structural properties of
obscured luminous active galactic nuclei from a detailed study of the
rest-frame $B$ and $I$ HST images of 29 nearby ($z\approx 0.04-0.4$) optically
selected type 2 quasars. Morphological classification reveals that only a
minority (34%) of the hosts are mergers or interacting galaxies. More than half
(55%) of the hosts contain regular disks, and a substantial fraction (38%), in
fact, are disk-dominated ($B/T\lesssim 0.2$) late-type galaxies with low Sersic
indices ($n < 2$), which is characteristic of pseudo bulges. The prevalence of
bars in the spiral host galaxies may be sufficient to supply the modest fuel
requirements needed to power the nuclear activity in these systems. Nuclear
star formation seems to be ubiquitous in the central regions, leading to
positive color gradients within the bulges and enhancements in the central
surface brightness of most systems.
