Clues to the Formation of Lenticular Galaxies Using Spectroscopic
  Bulge-Disk Decomposition
  Lenticular galaxies have long been thought of as evolved spirals, but the
processes involved to quench the star formation are still unclear. By studying
the individual star formation histories of the bulges and disks of lenticulars,
it is possible to look for clues to the processes that triggered their
transformation from spirals. To accomplish this feat, we present a new method
for spectroscopic bulge-disk decomposition, in which a long-slit spectrum is
decomposed into two one-dimensional spectra representing purely the bulge and
disk light. We present preliminary results from applying this method to
lenticular galaxies in the Virgo and Fornax Clusters, in which we show that the
most recent star formation activity in these galaxies occurred within the
bulges. We also find that the bulges are in general more Fe-enriched than the
disks of the same galaxy, and that this enrichment grows stronger as the age of
the bulge becomes younger. These results point towards a scenario where the
star formation in the disks of spiral galaxies are quenched, followed by a
burst of star formation in the central regions from the gas that has been
funnelled inwards through the disk.
